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WBA OpenRoaming Wireless Federation
draft-tomas-openroaming-08

Document Type Active Internet-Draft (individual)
Authors Bruno Tomas , Mark Grayson , Necati Canpolat , Elizabeth A Cockrell , Sri Gundavelli , Seb Adamski
Last updated 2026-06-12
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draft-tomas-openroaming-08
Independent Submission                                          B. Tomas
Internet-Draft                         Wireless Broadband Alliance, Inc.
Intended status: Informational                                M. Grayson
Expires: 14 December 2026                                  Cisco Systems
                                                             N. Canpolat
                                                       Intel Corporation
                                                          B. A. Cockrell
                                                             Independent
                                                           S. Gundavelli
                                                           Cisco Systems
                                                              S. Adamski
                                                                IronWiFi
                                                            12 June 2026

                  WBA OpenRoaming Wireless Federation
                       draft-tomas-openroaming-08

Abstract

   This document describes the Wireless Broadband Alliance's OpenRoaming
   system.  The OpenRoaming architecture enables a seamless onboarding
   experience for devices connecting to access networks that are part of
   the federation of access networks and identity providers.  The
   primary objective of this document is to describe the protocols that
   form the foundation for this architecture, enabling providers to
   correctly configure their equipment to support interoperable
   OpenRoaming signalling exchanges.  In addition, the topic of
   OpenRoaming has been raised in different IETF working groups, and
   therefore a secondary objective is to assist those discussions by
   describing the federation organization and framework.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at https://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on 14 December 2026.

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Copyright Notice

   Copyright (c) 2026 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents (https://trustee.ietf.org/
   license-info) in effect on the date of publication of this document.
   Please review these documents carefully, as they describe your rights
   and restrictions with respect to this document.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   4
     1.1.  Requirements Language . . . . . . . . . . . . . . . . . .   4
     1.2.  Terminology . . . . . . . . . . . . . . . . . . . . . . .   4
   2.  Wireless Broadband Alliance . . . . . . . . . . . . . . . . .   7
   3.  OpenRoaming Architecture  . . . . . . . . . . . . . . . . . .   8
   4.  Identifying OpenRoaming Entities  . . . . . . . . . . . . . .  11
   5.  Scaling Secured Signalling  . . . . . . . . . . . . . . . . .  12
   6.  IDP Discovery . . . . . . . . . . . . . . . . . . . . . . . .  14
     6.1.  Dynamic Discovery . . . . . . . . . . . . . . . . . . . .  14
     6.2.  Discovery of EAP-AKA/AKA' Servers . . . . . . . . . . . .  14
     6.3.  Proving a Discovered RadSec Server is Authoritative for a
           Realm . . . . . . . . . . . . . . . . . . . . . . . . . .  15
     6.4.  Co-existence with Other Federations . . . . . . . . . . .  16
   7.  Connection Management for Dynamically Discovered RadSec
           Peers . . . . . . . . . . . . . . . . . . . . . . . . . .  16
     7.1.  ANPs not supporting reverse CoA . . . . . . . . . . . . .  16
     7.2.  ANPs supporting reverse CoA . . . . . . . . . . . . . . .  17
     7.3.  Load Balancing RadSec Connections . . . . . . . . . . . .  18
     7.4.  Connection Management for IDP RadSec Servers  . . . . . .  18
   8.  OpenRoaming Passpoint Profile . . . . . . . . . . . . . . . .  18
     8.1.  OpenRoaming Policy Controls . . . . . . . . . . . . . . .  18
     8.2.  OpenRoaming Closed Access Group Policies  . . . . . . . .  19
       8.2.1.  Level of Assurance Policies . . . . . . . . . . . . .  20
       8.2.2.  Quality of Service Policies . . . . . . . . . . . . .  20
       8.2.3.  Privacy Policies  . . . . . . . . . . . . . . . . . .  24
       8.2.4.  ID-Type Policies  . . . . . . . . . . . . . . . . . .  25
       8.2.5.  On-boarding Credential Policies . . . . . . . . . . .  26
     8.3.  Prioritizing Policies . . . . . . . . . . . . . . . . . .  27
   9.  OpenRoaming RADIUS Profile  . . . . . . . . . . . . . . . . .  28
     9.1.  Operator-Name . . . . . . . . . . . . . . . . . . . . . .  28
     9.2.  Chargeable-User-Identity  . . . . . . . . . . . . . . . .  28
     9.3.  Location-Data/Location-Information  . . . . . . . . . . .  29
     9.4.  Session-Timeout . . . . . . . . . . . . . . . . . . . . .  29
     9.5.  Acct-Session-Id . . . . . . . . . . . . . . . . . . . . .  29
     9.6.  Acct-Multi-Session-Id . . . . . . . . . . . . . . . . . .  30

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     9.7.  Event-Timestamp . . . . . . . . . . . . . . . . . . . . .  30
     9.8.  Connect-Info  . . . . . . . . . . . . . . . . . . . . . .  30
     9.9.  Enhanced Reply-Message  . . . . . . . . . . . . . . . . .  31
     9.10. WBA-Identity-Provider . . . . . . . . . . . . . . . . . .  33
     9.11. WBA-Offered-Service . . . . . . . . . . . . . . . . . . .  33
     9.12. WLAN-Venue-Info . . . . . . . . . . . . . . . . . . . . .  33
     9.13. WBA-Custom-SLA  . . . . . . . . . . . . . . . . . . . . .  33
     9.14. Filter-Id . . . . . . . . . . . . . . . . . . . . . . . .  33
     9.15. Operator-NAS-Identifier . . . . . . . . . . . . . . . . .  34
     9.16. Reverse Change of Authorization . . . . . . . . . . . . .  34
     9.17. Additional Attributes Related to OpenRoaming Settled  . .  35
       9.17.1.  WBA-Financial-Clearing-Provider  . . . . . . . . . .  35
       9.17.2.  WBA-Data-Clearing-Provider . . . . . . . . . . . . .  36
       9.17.3.  WBA-Linear-Volume-Rate . . . . . . . . . . . . . . .  36
       9.17.4.  OpenRoaming Session Mediation  . . . . . . . . . . .  36
   10. Security Considerations . . . . . . . . . . . . . . . . . . .  36
     10.1.  Network Selection and Triggering Authentication  . . . .  36
     10.2.  ANP RadSec Connectivity  . . . . . . . . . . . . . . . .  37
     10.3.  Dynamic Discovery of RadSec Peers  . . . . . . . . . . .  37
     10.4.  End-User Traffic . . . . . . . . . . . . . . . . . . . .  38
     10.5.  ANP Inspection of End-User Traffic . . . . . . . . . . .  38
     10.6.  End-User Location  . . . . . . . . . . . . . . . . . . .  38
   11. Future Enhancements . . . . . . . . . . . . . . . . . . . . .  39
   12. IANA Considerations . . . . . . . . . . . . . . . . . . . . .  39
   13. References  . . . . . . . . . . . . . . . . . . . . . . . . .  39
     13.1.  Normative References . . . . . . . . . . . . . . . . . .  39
     13.2.  Informative References . . . . . . . . . . . . . . . . .  39
   Appendix A.  Example OpenRoaming Signalling Flow  . . . . . . . .  44
   Appendix B.  Example OpenRoaming RCOI Usage . . . . . . . . . . .  47
     B.1.  OpenRoaming RCOI Based Policy for Supporting QoS Tiers  .  47
     B.2.  OpenRoaming RCOI Based Policy for Supporting Identity Type
           Policies  . . . . . . . . . . . . . . . . . . . . . . . .  48
     B.3.  OpenRoaming RCOI Based Policy for Supporting Different
           Identity Proofing Policies  . . . . . . . . . . . . . . .  50
   Appendix C.  OpenRoaming Legal Framework  . . . . . . . . . . . .  52
     C.1.  Seamless Experience . . . . . . . . . . . . . . . . . . .  52
     C.2.  OpenRoaming Organization  . . . . . . . . . . . . . . . .  52
     C.3.  OpenRoaming Legal Terms . . . . . . . . . . . . . . . . .  53
     C.4.  ANP Performance Data  . . . . . . . . . . . . . . . . . .  54
     C.5.  Service Abuse . . . . . . . . . . . . . . . . . . . . . .  54
     C.6.  OpenRoaming Troubleshooting . . . . . . . . . . . . . . .  54
       C.6.1.  Issue Response  . . . . . . . . . . . . . . . . . . .  55
       C.6.2.  Issue Escalation  . . . . . . . . . . . . . . . . . .  55
     C.7.  Breach of Contract  . . . . . . . . . . . . . . . . . . .  56
   Changelog . . . . . . . . . . . . . . . . . . . . . . . . . . . .  56
   Acknowledgements  . . . . . . . . . . . . . . . . . . . . . . . .  57
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  57

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1.  Introduction

   WBA OpenRoaming is a roaming federation service of Access Network
   Providers (ANPs) and Identity Providers (IDPs), enabling an automatic
   and secure Wi-Fi experience globally.  WBA OpenRoaming creates the
   framework to seamlessly connect billions of users and things to
   millions of Wi-Fi networks.

   ANP-1 --\                    _----_                     /-- IDP-1
            \     Access      _( Open )_      Identity    /
   ANP-2  ---<==  Network ---(  Roaming )---  Providers <==-- IDP-2
            /     Providers   (_      _)                  \
   ANP-3 --/                    '----'                     \-- IDP-3

                      Figure 1: OpenRoaming Federation

   WBA OpenRoaming recognizes the benefits that the likes of eduroam
   [RFC7593] provides to the education and research community.  WBA
   OpenRoaming defines a global federation that is targeted at serving
   all communities, while supporting both settlement-free use cases
   where "free" Wi-Fi is being offered to end-users in order to support
   some alternative value proposition, as well as traditional settled
   "paid" for Wi-Fi offered by some cellular providers.

   OpenRoaming is designed to deliver end-to-end security between a
   Network Access Server (NAS) deployed by an OpenRoaming Access Network
   Provider and an EAP Server [RFC3748] deployed by an OpenRoaming
   Identity Provider.  The security of the solution is based on mTLS
   using certificates issued under Wireless Broadband Alliance's Public
   Key Infrastructure [RFC5280].

1.1.  Requirements Language

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in BCP
   14 [RFC2119] [RFC8174] when, and only when, they appear in all
   capitals, as shown here.

1.2.  Terminology

   Access Network Query Protocol (ANQP):

      An IEEE 802.11 defined protocol that allows for access network
      information retrieval in a pre-association state.  ANQP has been
      further extended by the Wi-Fi Alliance (WFA) as part of its
      Passpoint program [PASSPOINT].

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   Access Network Provider (ANP):

      An entity that has joined the federation and serves OpenRoaming
      end-users by configuring the OpenRoaming RCOI(s) on its Wi-Fi
      equipment.  Entities do not have to join the WBA in order to
      oeprate as an OpenRoaming ANP.

   Broker:

      An entity that is a WBA member which has joined the federation and
      performs certain specific roles to help scale the operation of the
      federation.  The separate roles of a broker can include:

      1.  Assigning WBA identities (WBAIDs) to ANPs and IDPs.

         2.  Operating an issuing intermediate certification authority
             under the WBA's PKI and issuing certificates to ANPs and
             IDPs.

         3.  Operating a registration authority to a third party
             operated issuing intermediate certification authority under
             WBA's PKI to enable certificates to be issued to ANPs, hub-
             providers and IDPs.

   Closed Access Group (CAG):

      The definition of the 12 most significant bits of an OUI-36 RCOI
      to indicate OpenRoaming policy controls that can be enforced by
      ANPs and IDPs.

   Identity Provider (IDP):

      An entity that has joined the federation and includes the
      OpenRoaming RCOI(s) in the Passpoint profile of its end-user
      devices and authenticates end-user devices on OpenRoaming ANP
      networks.  Entities do not have to join the WBA in order to
      oeprate as an OpenRoaming IDP.

   Level of Assurance (LoA):

      An ISO/IEC 29115 term [ISO29115] that is used to define equivalent
      levels for handling of end-user enrollment, credential management
      and authentication amongst different IDPs.

   OpenRoaming-Settled:

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      The "base RCOI" of BA-A2-D0 that is used to indicate that the ANP
      expects to receive payment for providing OpenRoaming service to
      end-users.

   OpenRoaming-Settlement-Free:

      The "base RCOI" of 5A-03-BA that is used to indicate that the ANP
      provides the OpenRoaming service to end-users at no cost to the
      IDP.

   Passpoint Profile:

      Passpoint is a Wi-Fi Alliance (WFA) certification program that
      defines the use a Passpoint profile, that includes the user's
      credentials and the access network identifiers, that enables Wi-Fi
      devices to automatically discover and authenticate to Wi-Fi
      hotspots that provide Internet access [PASSPOINT].

   PLMN Id:

      A unique identifier for a mobile network (cellular) operator.  The
      identifier consists of a MCC (Mobile Country Code) and a MNC
      (Mobile Network Code).  ITU-T Recommendation [E212] defines both
      MCC and MNC.  The ITU allocates MCC values to national regulators
      who are then responsible for allocating MNC values to individual
      mobile network operators.  [PASSPOINT] defines how the PLMN Id can
      be sent in ANQP messages.

   Roaming Consortium Identifier (RCOI):

      An RCOI identifies the groups of identity providers that are
      supported by the network.  It is a 3-octet, or a 5-octet value
      carried in the 802.11 beacon information element (IE).  It is also
      sent in the ANQP messages.  Based on the access technologies, the
      specific link-layer protocols will be used for carrying the RCOI.
      RCOI is also part of the Passpoint profile.

      NOTE: OpenRoaming only uses 5-octet RCOIs.

   Subscriber Identity Module (SIM):

      The SIM is traditionally a smart card distributed by a mobile
      operator.

   WBA Identity (WBAID):

      A hierarchical namespace that is used to uniquely identify every
      OpenRoaming entity (ANP, IDP, broker or hub-provider).

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   Wireless Roaming Intermediary eXchange (WRIX):

      A framework, aimed at facilitating interconnectivity between
      operators and the Wi-Fi roaming hub services.

2.  Wireless Broadband Alliance

   The Wireless Broadband Alliance (WBA) defines the Wireless Roaming
   Intermediary eXchange (WRIX) framework, aimed at facilitating
   interconnectivity between Wi-Fi operators and the Wi-Fi roaming hub
   services, as well as the Carrier Wi-Fi Services program that provides
   guidelines to improve customer experience on Carrier Wi-Fi networks.
   Both of these programs leverage the Wi-Fi Alliance specified
   Passpoint functionality [PASSPOINT] to enable automatic and secure
   connectivity to Wi-Fi networks, allowing devices to be provisioned
   with network access credentials with minimal user interaction.

   WBA programs have traditionally focussed on "offloading" cell phone
   data from cellular networks onto Wi-Fi networks.  Deployments of such
   systems have seen uneven adoption across geographies, with cellular
   operators frequently limiting their engagement to premier locations
   that have deployed Wi-Fi and experience a significant footfall of
   operator's customers.

   Whereas conventional Carrier Wi-Fi has focused on premier locations,
   the last decade has seen a continued increase in the requirements of
   private Wi-Fi networks to be able to serve visitors, contractors and
   guest users.  Moreover, in most of these scenarios, the Wi-Fi network
   is primarily being used to support some alternative value
   proposition; an improved retail experience in a shopping mall, a more
   efficient meeting in a carpeted office, a superior stay in a
   hospitality venue, or a better fan experience in a sporting arena.
   Traditionally, this segment has made wide-scale use of captive
   portals and unencrypted Wi-Fi links to onboard end-users onto their
   networks [RFC8952].  However, increasing concerns around sending
   Internet traffic over open, untrusted networks, together with the
   decreasing costs for cellular data, mean that end-users are less
   motivated to search out and attach to such "free" Wi-Fi networks, and
   as a consequence, captive portal conversion rates continue to
   decrease.

   As a consequence, in 2020 WBA launched its OpenRoaming federation,
   designed to provide a better on-boarding experience to end-users,
   that is seamless, scalable and secure.

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3.  OpenRoaming Architecture

   Figure 2 contrasts a conventional carrier Wi-Fi roaming system with
   OpenRoaming.  As illustrated, conventional Wi-Fi roaming has
   typically been based on:

   1.  IPSec [RFC6071] tunnels established between access networks, hub-
       providers and identity providers used to protect exchanged
       signalling.

   2.  Static routing of RADIUS signalling [RFC2865] based on realm
       routing tables populated according to agreements between access
       networks and hub-providers.

   3.  Passpoint primarily used with SIM based identifiers, where
       individual PLMN Ids are configured on the access networks WLAN
       equipment enabling them to be sent in ANQP messages, and cellular
       providers enable Passpoint based SIM authentication in end-user
       devices.

   4.  EAP-AKA [RFC4187] based Passpoint authentication exchanged
       between the Supplicant in the end-user device and the EAP Server
       in the cellular provider's network.

   5.  A primary focus on carrier based identities where the end-user
       has a billing relationship with the carrier.

   In contrast, OpenRoaming is based on:

   1.  RadSec signalling [RFC6614] secured using mTLS with certificates
       issued under WBA's private certification authority.

   2.  Dynamic routing of RADIUS based on DNS-based discovery of
       signalling peers, as specified in [RFC7585].

   3.  Passpoint based network selection based on 36-bit Roaming
       Consortium Organization Identifiers (RCOIs), where WBA defines
       the use of the 12 most significant bits of the 36-bit RCOI to
       embed closed access group policies.

   4.  Passpoint authentication that can use any suitable EAP method.

   5.  Encompassing new identity providers who do not necessarily have a
       billing relationship with their end-users.

   Example EAP methods used with Passpoint include EAP-TLS, EAP-SIM,
   EAP-AKA, EAP-AKA' and EAP-TTLS with MS-CHAP-V2 that are included in
   Table 4 of the Passpoint specification [PASSPOINT].  In addition to

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   these 5 EAP methods, Wi-Fi devices are available that can be
   configured to use different EAP type with Passpoint, including
   Passpoint with Protected EAP (PEAP) [PEAP], EAP-TEAP [RFC7170] and
   EAP-FAST [RFC4851] outer methods, together with alternative inner
   methods to MS-CHAP-V2 used inside EAP-TTLS, including EAP-TLS.
   Because OpenRoaming ANPs have no direct relationship with OpenRoaming
   IDPs that decide the credential type and EAP method to use when
   authenticating end-user devices, OpenRoaming ANPs SHOULD ensure that
   all EAP Methods compatible with Passpoint can be used to authenticate
   end-user devices.

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   +---------+        +--------+        +--------+        +--------+
   | Visited |        | Wi-Fi  |        | Wi-Fi  |        |Cellular|
   |  Wi-Fi  |        |  Hub   |        |  Hub   |        |Provider|
   | Network |<------>|Provider|<------>|Provider|<------>|Network |
   |         | RADIUS |        | RADIUS |        | RADIUS |        |
   |   NAS   |        | RADIUS |        | RADIUS |        | RADIUS |
   |         |<------>| proxy  |<------>| proxy  |<------>| Server |
   |Passpoint| IPSec  +--------+ IPSec  +--------+ IPSec  +--------+
   |PLMNId(s)|
   +---------+
       /|\
        |
       \|/
   +---------+         A) Conventional Carrier Wi-Fi
   |Passpoint|
   | device  |
   |  with   |
   | PLMN-Id |
   | profile |
   +---------+

   +---------+                   +---+                    +--------+
   | Visited |<----------------->|DNS|<------------------>|Identity|
   |  Wi-Fi  |   DNS based peer  +---+  Configure NAPTR,  |Provider|
   | Network |      discovery            SRV and A/AAAA   |Network |
   |         |                              records       |        |
   |   NAS   |                                            | RADIUS |
   |         |<------------------------------------------>| Server |
   |Passpoint|        RadSec/TLS secured using mTLS       +--------+
   | RCOI(s) |               and WBA PKI
   +---------+
       /|\
        |
       \|/
   +---------+              B) OpenRoaming
   |Passpoint|
   | device  |
   |  with   |
   | RCOI(s) |
   | profile |
   +---------+

      Figure 2: Contrasting Conventional Carrier Wi-Fi and OpenRoaming
                               Architectures

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4.  Identifying OpenRoaming Entities

   All OpenRoaming providers (access, identity and hub) and OpenRoaming
   brokers are allocated a WBA Identity (WBAID).  The WBAID is defined
   to be transported in the RADIUS Operator-Name attribute (#126)
   [RFC5580].  WBA has been allocated the Operator Namespace identifier
   0x34 "4" to identify an Operator-Name attribute carrying a WBAID.

   The WBAID is a hierarchical namespace that comprises at its top level
   the identity allocated by WBA to a WBA Member and is of the form
   shown in Figure 3 where the optional 2 upper case characters
   represent an ISO-3166 Alpha-2 country code [ISO3166] e.g.,
   "WBAMEMBER:US".

   WBAID         = member-string [ ":" country-code ]

   member-string = 1*( member-char )

   member-char   = UPPERALPHA / DIGIT / SPECIAL

   country-code  = 2UPPERALPHA

   UPPERALPHA    = %x41-5A  ; "A"-"Z"
   DIGIT         = %x30-39  ; "0"-"9"

   ; SPECIAL: permitted special characters
   ; excludes ":", ".", "_", "#", pound (%xA3), "*", '"'

   SPECIAL       = %x21 / %x24-26 / %x28-29 / %x2B-2D /
                   %x2F / %x3C-40 / %x5B-5E / %x7B-7E

            Figure 3: ABNF definition of Primary WBAID Structure

   When operating as an OpenRoaming broker, the WBA Member is able to
   allocate subordinate identities to OpenRoaming providers who are not
   WBA members by pre-pending a subordinate identity , plus "." (%x2e)
   to the Member's WBAID, e.g., a broker assigned the WBAID
   "WBAMEMBER:US" by the WBA is able to assign the WBAID
   "OPENROAMINGPROVIDER.WBAMEMBER:US" to a third-party ANP/IDP who has
   agreed terms with the broker and joined the federation.  In this way,
   any receiving entity of a WBAID can identify the WBA Member who is
   acting as an OpenRoaming broker to the provider by assigning it an
   identity.

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5.  Scaling Secured Signalling

   As described in Appendix C, the OpenRoaming legal framework does not
   assume any direct relationship between ANPs and IDPs.  In order to
   scale the secured signalling between providers, the federation makes
   use of a Public Key Infrastructure (PKI) using a private Certificate
   Authority specifically designed to secure the operations of the
   roaming federation.  WBA and its members have published the WBA
   Certificate Policy [WBAPKICP] that defines the policies which govern
   the operations of the PKI components by all individuals and entities
   within the infrastructure.  The OID for Wireless Broadband Alliance
   is:

      { iso(1) identified-organization(3) dod(6) internet(1) private(4)
      enterprise(1) The Wireless Broadband Alliance(14122) }

   The Wireless Broadband Alliance organizes its OID arcs for the
   Certificates Policy Documents using the object identifier
   1.3.6.1.4.1.14122.1.1.  At the time of writing, the current
   certificate policy is 1.3.6.1.4.1.14122.1.1.7.

   This Certificate Policy is based on a 4-level hierarchy, as
   illustrated in Figure 4.

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   +---------+-------------------------+---------------------------+
   | Level   | Description             |  Comment                  |
   +---------+-------------------------+---------------------------+
   | Level 1 | OpenRoaming Root        | Operation managed by WBA. |
   |         | Certificate Authority   |                           |
   +---------+-------------------------+---------------------------+
   | Level 2 | OpenRoaming Policy      | Operation managed by WBA. |
   |         | Intermediate Certificate| Instantiates WBA policy   |
   |         | Authority               | OID.                      |
   +---------+-------------------------+---------------------------+
   | Level 3 | OpenRoaming Issuing     | Operated by an OpenRoaming|
   |         | Intermediate Certificate| broker.                   |
   |         | Authority               |                           |
   +---------+-------------------------+---------------------------+
   | Level 3 | OpenRoaming Registration| Optional and when used,   |
   |         | Authority               | operated by an OpenRoaming|
   |         |                         | broker.                   |
   +---------+-------------------------+---------------------------+
   | Level 4 | OpenRoaming Entity      | A WBA member or           |
   |         |                         | non-member. WBA's         |
   |         |                         | Certificate Policy        |
   |         |                         | requires the Entity's     |
   |         |                         | WBAID is included in the  |
   |         |                         | Subject UID field in the  |
   |         |                         | certificate.              |
   +---------+-------------------------+---------------------------+

                    Figure 4: OpenRoaming PKI Hierarchy

   Certificates issued under the WBA PKI are used by Entities to perform
   mutual authentication with other Entities and to secure RadSec
   signalling [RFC6614] that carries EAP-based Passpoint authentication.
   This is typically between a RadSec client in the OpenRoaming ANP's
   network and an RadSec Server in the OpenRoaming IDP's network,
   although a provider can decide to outsource the operation of the
   RadSec endpoint to a third party provider.

   OpenRoaming is a distributed federation that lacks a centralized
   RADIUS element for identifying and troubleshooting signalling issues.
   Instead, the WBA operates cloud-based systems capable of verifying
   the correct configuration of DNS and TLS endpoints for OpenRoaming
   IDPs that have registered their realms with the WBA.  This baseline
   testing by the WBA ensures that ANPs and IDPs can establish a TLS
   connection, such as when an end-user from an IDP roams into the
   coverage area of Wi-Fi networks operated by an ANP.

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   To provide a scalable system that enables access and identity
   providers to collaboratively troubleshoot and resolve issues, the WBA
   Certificate Practice Statement [WBAPKICPS] REQUIRES the Subject
   Alternative Name (SAN) attribute in issued end-entity certificates
   includes a contact email address responsible for handling issues
   raised by third-party providers.  The OpenRoaming legal framework
   requires ANPs and IDPs to make reasonable efforts to support
   troubleshooting procedures.  This includes monitoring the email
   address listed in the SAN attribute of the certificate and responding
   to any issues raised by legitimate third parties.

6.  IDP Discovery

6.1.  Dynamic Discovery

   OpenRoaming defines the use of dynamic discovery [RFC7585] by which
   an ANP discovers the IP address of the IDP's RadSec server.  Whereas
   [RFC7585] defines the use of separate service tags for identifying
   RADIUS Authentication ("aaa+auth") and RADIUS Accounting ("aaa+acct")
   servers, OpenRoaming uses the "aaa+auth" tag to identify the IP
   address of a RadSec server that supports both RADIUS authentication
   and accounting.

   [RFC7585] additionally defines the use of DNS to enable the dynamic
   discovery of a RADIUS endpoint for supporting dynamic authorization
   services, i.e., for RADIUS Change of Authorization (CoA) and
   Disconnect Message (DM) support.  OpenRoaming does not use dynamic
   discovery for dynamic authorization, instead defining the use of
   "reverse CoA" [I-D.draft-ietf-radext-reverse-coa] that allows an IDP
   to send CoA packets in "reverse" down a RADIUS/TLS connection that
   was previously established by an ANP originated signaling exchange,
   as defined in Section 9.16.

6.2.  Discovery of EAP-AKA/AKA' Servers

   Passpoint defines the use of EAP-AKA' based authentication [RFC5448]
   which uses the 3GPP 23.003 [TS23003] defined realm of
   wlan.mnc<mnc>.mcc<mcc>.3gppnetwork.org, where <mcc> represent an
   E.212 Mobile Country Code and <mnc> represents the E.212 Mobile
   Network Code allocated to the IDP.  GSMA is responsible for operating
   the 3gppnetwork.org domain and GSMA IR.67 [GSMAIR67] limits access to
   the DNS systems supporting such records to those systems connected to
   the inter-PLMN IP backbone (known as "GRX/IPX").  As OpenRoaming ANPs
   do not connect to this inter-PLMN backbone, then conventional realm
   based lookup cannot be used over the Internet to discover the RadSec
   server supporting EAP-AKA' authentication.

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   GSMA IR.67 does allow systems to be discoverable from the public
   Internet, specifically calling out the use of the pub.3gppnetwork.org
   sub-domain name for such procedures.  In order for ANPs to
   dynamically discover the RadSec server supporting EAP-AKA'
   authentication, GSMA has defined the use of the
   wlan.mnc<mnc>.mcc<mcc>.pub.3gppnetwork.org by OpenRoaming systems.
   This means that whenever a RadSec client receives a user-name
   containing an NAI formatted as
   user@wlan.mnc<mnc>.mcc<mcc>.3gppnetwork.org, the dynamic peer
   detection functionality MUST insert ".pub" into the realm and perform
   DNS based dynamic discovery using the
   wlan.mnc<mnc>.mcc<mcc>.pub.3gppnetwork.org domain name.  The RADIUS
   user-name attribute MUST NOT be similarly modified.

   IR.67 defines the procedure by which a cellular operator can request
   the delegation of their mnc<mnc>.mcc<mcc>.pub.3gppnetwork.org sub-
   domain.  GSMA PRD IR.67 also allows an MNO to delegate the entire
   mnc<MNC>.mcc<MCC>.pub.3gppnetwork.org sub-domain which could have
   already occurred, e.g., to enable use of the
   epdg.epc.mnc<MNC>.mcc<MCC>.pub.3gppnetwork.org domain used with
   3GPP's Wi-Fi calling service.  Using this approach, a cellular
   operator operating as an OpenRoaming IDP can authenticate their end-
   users on third party ANP Wi-Fi networks.

6.3.  Proving a Discovered RadSec Server is Authoritative for a Realm

   The OpenRoaming preferred approach to dynamically discover the RadSec
   server IP address serving a particular realm or set of realms is to
   use DNS records that are protected with DNSSEC [RFC9364].  However,
   GSMA has not enabled DNSSEC on its 3gppnetwork.org domain, meaning
   that DNSSEC cannot be applied on the publicly resolvable domains
   under pub.3gppnetwork.org.  Because of this situation, OpenRoaming
   does not currently mandate operation of DNSSEC.

   If the DNS records for a realm are not protected with DNSSEC, because
   the realm has been provided directly by the OpenRoaming end-user, the
   IDP SHOULD ensure that the discovered RadSec server(s) supporting its
   realm(s) is/are configured with a WBA-PKI server certificate that
   includes the realm(s) used in the dynamic peer detection in the
   certificate SubjectAltName.

   Where the DNS records are protected with DNSSEC, the IDP SHOULD
   ensure that the discovered RadSec server(s) supporting its realm(s)
   is/are configured with a WBA-PKI server certificate that includes the
   derived name(s) from the secured DNS NAPTR/SRV query in the
   certificate SubjectAltName.

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   Where the OpenRoaming IDP has offloaded the operation of RadSec
   termination to a third party hub-provider that is responsible for
   supporting a number of independent realms, the hub-provider SHOULD
   ensure that the discovered RadSec server(s) supporting the
   independent realms from its partner IDPs is/are configured with a
   WBA-PKI server certificate that includes the derived name(s) from the
   DNS NAPTR/SRV query in the certificate SubjectAltName.

6.4.  Co-existence with Other Federations

   Other federations which want to interface to the OpenRoaming
   federation may use dynamic discovery with distinct NAPTR application
   service tags to facilitate integration.  For example, an eduroam
   service provider can use the use the "x-eduroam" application service
   tag, specified in [RFC7593], to discover the home institution's
   RadSec peer for authentication, and OpenRoaming ANPs can use the
   "aaa+auth" tag to discover a separate RadSec peer that can be defined
   for handling all inter-domain authentications.

   Where a separate inter-federation RadSec peer is not used, the other
   federation AAA operating as an OpenRoaming IDP needs to determine
   which certificate chain to return in its ServerHello message.  An
   OpenRoaming ANP operating with TLS 1.3 SHOULD use the
   "certificate_authorities" extension [RFC8446] in its ClientHello
   message to indicate that the ANP supports the WBA PKI Certification
   Authority trust anchor.  Similarly, an OpenRoaming ANP operating
   using TLS 1.2 SHOULD use the "trusted_ca_keys" extension [RFC6066] in
   its ClientHello message to indicate the DistinguishedName of the WBA
   PKI Certification Authority whose root keys the ANP possesses.  The
   federation AAA operating as an OpenRoaming IDP MAY use information in
   the ClientHello extension to guide its certificate selection.

7.  Connection Management for Dynamically Discovered RadSec Peers

   The procedures for connection management for dynamically discovered
   peers depends on whether the ANP supports reverse CoA functionality,
   as defined in Section 9.16.

7.1.  ANPs not supporting reverse CoA

   An OpenRoaming ANP MAY operate with a short TCP idle timeout,
   sufficient to complete the RADIUS Access-Request exchange and the
   initial RADIUS Accounting-Request exchange with Acct-Status-Type set
   to "Start".  Subsequent RADIUS Accounting-Request messages to the IDP
   may require TLS resumption, for example, if no other inbound roamers
   from the IDP are active on the ANP's network.

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      NOTE: When performing TLS resumption, the ANP MUST consider the
      server IP address stale if its corresponding DNS record has
      expired and perform a new DNS query to resolve the current IP
      address.

   Operation using short TCP-idle timeouts avoids the need for the
   operation of an additional RADIUS application watchdog.  In such
   cases, ANPs are NOT REQUIRED to support Status-Server extension as a
   RADIUS application-level watchdog.

7.2.  ANPs supporting reverse CoA

   An OpenRoaming ANP supporting the reverse CoA functionality defined
   in Section 9.16 SHOULD manage connections such that the RadSec
   connection to the dynamically discovered peer is considered as
   "temporarily static" while active RADIUS sessions exist that may
   require the sending of future CoA packets.

   While the connection is "temporarily static", the ANP MUST monitor
   the RadSec connection liveness.  The ANP SHOULD use the Status-Server
   extension, defined in [RFC5997] for monitoring the liveness of a
   RadSec connection.  IDPs and hubs supporting OpenRoaming settled-
   service MUST respond to Status-Server requests.

      NOTE 1: OpenRoaming recognizes that despite [RFC5997] recommending
      RADIUS clients SHOULD NOT generate RADIUS Access-Request packets
      solely to see if a server is alive, some OpenRoaming ANPs do use
      RADIUS Access-Request for such purposes.  In such cases, the
      Access-Request MUST be sufficient for the IDP to reject the
      request without performing an Access-Challenge.

   The OpenRoaming ANP supporting reverse CoA MUST NOT configure any
   TCP-idle timeout shorter than the shortest inter-RADIUS message
   duration, (e.g., the accounting interim period or connection
   liveliness checking repetition period).  Reconnection procedures
   SHOULD follow section 3.8.1 of [I-D.ietf-radext-radiusdtls-bis].
   This section REQUIRES the ANP implement an algorithm for handling the
   timing of such reconnection attempts that includes an exponential
   back-off.

      NOTE 2: When performing TLS-reconnection, the ANP MUST consider
      the server IP as stale when its corresponding DNS record has
      expired and perform a new DNS query to resolve the current IP
      address.

      NOTE 3: This does not prevent an ANP performing a new DNS query,
      e.g., if a reconnection attempt fails in case the server has had
      its IP address configuration changed unexpectedly.

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7.3.  Load Balancing RadSec Connections

   An ANP MAY perform load balancing on dynamically discovered RadSec
   connections, according to the ANPs load balancing policies.  Load
   balancing can trigger the opening of a new TLS connection to a RadSec
   server even if an existing TLS session is present.  ANPs that support
   reverse CoA MUST use the same TLS session for sending RADIUS Access-
   Request and RADIUS Accounting-Request messages that correspond to the
   same individual user session.

7.4.  Connection Management for IDP RadSec Servers

   Since TCP-idle timeout and reverse CoA support are ANP policies, all
   IDPs and hubs SHOULD enable support for Status-Server extension, as
   specified in [RFC5997].

   Dynamically established connections between ANPs and IDPs with
   frequent authentication exchanges may never trigger idle timeouts,
   potentially hindering IDPs from updating RadSec server IP address
   configurations.  IDPs can operate their DNS systems and RadSec
   servers TCP configuration to facilitate RadSec server IP address re-
   configuration.  For example, a DNS TTL of 86400 seconds coupled with
   a maximum TCP connection lifetime of 86400 seconds, ensures that
   connections between ANPs and IDPs experiencing frequent
   authentications are re-established using an updated DNS record at
   least once every 24 hours.  In such cases, if the session was closed
   by the RadSec server, the ANP SHOULD NOT consider the closure as
   normal.  If the ANP supports reverse CoA, the ANP SHOULD follow
   section 3.8.1 of [I-D.ietf-radext-radiusdtls-bis] that permits the
   triggering of an immediate reconnection to the RadSec server by the
   ANP.

8.  OpenRoaming Passpoint Profile

8.1.  OpenRoaming Policy Controls

   In order to avoid possible fragmentation of roaming federations,
   OpenRoaming recognizes that there is a need to permit OpenRoaming to
   be integrated into a variety of different use-cases and value
   propositions.  These use-cases include scenarios where providers are
   able to enforce policy controls of which end-users are authorized to
   access the service.  The realization of authorization policy controls
   in the OpenRoaming federation is a balance between the requirements
   for fine grain policy enforcement versus the potential impact of
   policy enforcement (access rejection) on the end-user experience.

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   Such a level of control is realized using Closed Access Group (CAG)
   based policies.  A Closed Access Group identifies a group of
   OpenRoaming users who are permitted to access one or more OpenRoaming
   access networks configured with a particular CAG policy.  These
   Closed Access Group policies are encoded using one or more Roaming
   Consortium Organization Identifiers (RCOIs), first defined in
   Passpoint Release 1.0, and well supported across the smartphone
   device ecosystem.

      NOTE: encoding CAG policies in OpenRoaming using one or more RCOIs
      is aimed at delivering an equivalent functionality to the CAG
      policies encoded in 3GPP using one or more CAG-IDs.

8.2.  OpenRoaming Closed Access Group Policies

   OpenRoaming defines the use of multiple RCOIs to facilitate the
   implementation of Closed Access Group policies across the federation.
   The currently defined RCOIs are:

   *  OpenRoaming-Settled: BA-A2-D0-xx-x

   *  OpenRoaming-Settlement-Free: 5A-03-BA-xx-x

   Figure 5 shows how the 24-bit length OpenRoaming RCOIs are further
   extended into 36-bit length OUI-36s with additional context dependent
   identifiers used to encode specific Closed Access Group policies.
   Following Passpoint Release 1.0 specification, only when there is a
   bitwise match of all 36 bits of the configured RCOI in the WLAN
   equipment and the Passpoint profile configured in the end-user device
   will an EAP authentication be triggered.

   The encoding of Closed Access Group policies is defined so that the
   "no-restrictions" policy is encoded using the 12-bit value "00-0",
   i.e., 54-03-BA-00-0 represents a policy that accepts all OpenRoaming
   settlement-free end-users onto a particular ANP installation.

   +---------------------------------------+-------------------+
   |               OUI-36 Octet 4          |  OUI-36 Octet 5   |
   +---------------------------------------+-------------------+
   | B7 | B6 | B5 | B4 | B3 | B2 | B1 | B0 | B7 | B6 | B5 | B4 |
   +----+---------+----+-------------------+-------------------+
   | LoA|   QoS   |PID |     ID-Type       |On-b|  Reserved -  |
   |    |         |    |                   |oard|   set to 0   |
   +----+---------+----+-------------------+-------------------+

       Figure 5: Extension of Octets 4 and 5 for OpenRoaming Context
                            Dependent RCOI Field

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8.2.1.  Level of Assurance Policies

   The format of the Level of Assurance (LoA) field is as shown in
   Figure 6.

   +-----------------------------------------------------------+
   |  LoA Field  |           Description                       |
   +-----------------------------------------------------------+
   |     B7      |                                             |
   +-----------------------------------------------------------+
   |     0       |   Baseline Identity Proofing                |
   +-----------------------------------------------------------+
   |     1       |   Enhanced Identity Proofing                |
   +-----------------------------------------------------------+

                    Figure 6: OpenRoaming CAG LoA Field

   The baseline identity proofing requirement on IDPs ensures that all
   OpenRoaming identities are managed with at least a medium level of
   assurance (LoA level 2) for end-user enrollment, credential
   management and authentication, as specified in ISO/IEC 29115
   [ISO29115].

   The LoA field is used to support ANPs which operate in regulatory
   regimes that require enhanced identity proofing to be used in the
   provision of credentials on OpenRoaming devices, equivalent to LoA
   level 3 in ISO/IEC29115 [ISO29115].  In such a scenario, the ANP can
   set the LoA bit field to 1 in all configured RCOIs to ensure that
   only identities provisioned using enhanced LoA 3 procedures can
   access via the ANP's network.

   Any IDP that manages its identities according to ISO/IEC 29115 LoA
   level 2 MUST NOT configure any RCOI in their end-users' Passpoint
   profile with the LoA field set to "1".  Conversely, an IDP that
   manages its identities according to ISO/IEC 29115 LoA level 3 MAY
   configure multiple RCOIs in their end-users' Passpoint profile,
   including RCOIs with the LoA field set to "0" and RCOIs with the LoA
   field set to "1".

8.2.2.  Quality of Service Policies

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8.2.2.1.  Access Network Requirements

   One of the challenges faced by users of Wi-Fi hotspots is when the
   Wi-Fi network is configured sub-optimally and results in a poor user
   experience.  Often the only remedy open to a user it to disable the
   Wi-Fi interface on their smartphone and continue to use cellular
   data.  This is especially the case where the Wi-Fi hotspot has been
   automatically selected with no user intervention.  As a consequence,
   OpenRoaming defines specific service tiers across the federation and
   uses the QoS field to differentiate between different tiers.  The
   format of the QoS field is shown in Figure 7.

   +-----------------------------------------------------------+
   |            QoS Field              |      Description      |
   +-----------------------------------------------------------+
   |        B6       |        B5       |                       |
   +-----------------------------------------------------------+
   |        0        |        0        |        Bronze         |
   +-----------------------------------------------------------+
   |        0        |        1        |        Silver         |
   +-----------------------------------------------------------+
   |        1        |        0        |       Reserved        |
   +-----------------------------------------------------------+
   |        1        |        1        |       Reserved        |
   +-----------------------------------------------------------+

                    Figure 7: OpenRoaming CAG QoS Field

   The "Bronze" and "Silver" values of QoS field are used to identify
   specific minimum quality of service policy aspects.

   The bronze service tier corresponds to the following:

   1.  The availability of OpenRoaming service when used to access the
       Internet measured during scheduled operations across the ANP's
       network exceeds 90% over any one month period.

   2.  The ANP shall ensure that the maximum download speed that end-
       Users can access the Internet shall be at least 50 megabits per
       second.

   3.  During the busy hour, the aggregate bandwidth used to receive
       Internet service on the ANP's network is sufficient to enable
       each and every authenticated and authorized OpenRoaming end-user
       to simultaneously receive a sustained 256 kilobits per second
       connection.

   The silver service tier corresponds to the following:

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   1.  The availability of OpenRoaming service when used to access the
       Internet measured during scheduled operations across the ANP's
       network exceeds 95% over any one month period.

   2.  The ANP shall ensure that the maximum download speed that end-
       users can access the Internet shall be at least 100 megabits per
       second.

   3.  During the busy hour, the aggregate bandwidth used to receive
       Internet service on the ANP's network is be sufficient to enable
       each and every authenticated and authorized end-user to receive a
       sustained 512 kilobits per second connection.

   4.  At least 10% of authenticated and authorized users are able to
       stream video content at a downlink rate of at least 5 megabits
       per second (when measured over a one-minute interval) over all of
       the ANP's OpenRoaming enabled Wi-Fi networks.

   5.  The authenticated and authorized end-users are able to stream
       video from one or more third party content distribution networks
       with an end-to-end latency of less than 150ms from all of the
       ANP's OpenRoaming enabled Wi-Fi networks.

   The QoS field can be used by those IDPs that are only interested in
   providing their end-users with a higher quality service level when
   automatically authenticated onto an OpenRoaming network.  For
   example, an IDP configures the QoS field as bronze in a Passpoint
   profile that uses the "5A-03-BA" settlement free RCOI and configures
   the QoS field as silver in a Passpoint profile that uses the "BA-
   A2-D0" OpenRoaming-settled paid service.

   ANPs that only support the bronze service tier MUST set the QoS Field
   to "00" in all RCOIs configured on their WLAN equipment.  ANPs that
   support the silver service tier MAY configure multiple RCOIs on their
   WLAN equipment that include values where the QoS field is set to "01"
   and values where the QoS field is set to "00".

   Exceptionally, ANPs that operate OpenRoaming installations on moving
   platforms are permitted to deviate from the normal OpenRoaming
   service level requirements listed above.  This is because such
   installations can necessitate use of cellular-based backhaul and/or
   backhaul via Non-Terrestrial Networks (NTN) which may not be able to
   meet the OpenRoaming minimum "bronze" service level requirements.  If
   an ANP wants to benefit from such deviations, it MUST signal using
   the WLAN-Venue-Info attribute [RFC7268] that it is operating in a
   venue category identified using a Venue Group value of "10", which is
   defined in Section 8.4.1.34 of [IEEE80211] as being used for
   vehicular installations.  In such cases, the OpenRoaming ANP MAY

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   signal one or more WBA-Custom-SLA vendor specific attributes
   Section 9.13 to indicate one or more (availability, per-user
   sustained bandwidth) tuples to the IDP.

   OpenRoaming also defines the ability of the ANP to signal additional
   real-time metrics associated with the Wi-Fi connection to an end-
   user, using the enhanced syntax for the RADIUS Connect-Info
   attributes as defined in Section 9.8.  This information can be used
   by an IDP to derive a quality metric for the performance of the ANP's
   OpenRoaming Wi-Fi network.

8.2.2.2.  Identity Provider Requirements

   Irrespective of the service-levels supported by their users, the IDP
   shall ensure that the availability of their authentication service
   measured during scheduled operations shall exceed 99% over any one
   month period.

8.2.2.3.  Rationale for Busy Hour Sustained Throughput Values

   The ANP requirements for sustained busy hour throughput requirements
   defined in Section 8.2.2.1 are based on equating a notional per month
   consumption to a sustained busy hour throughput.  The following
   calculation represents the mapping of sustained throughput to monthly
   consumption.

   *  Busy hour sustained throughput = 256 kilobits per second

   *  Busy hour consumption = 256 x 1024 x 3600 / 8 = 118 megabytes per
      hour

   *  Daily consumption, assuming 7% consumed in busy hour = 118 / 0.07
      = 1.69 gigabytes

   *  Monthly consumption, assuming 22 busy days per month = 1.69 x 22 =
      37.1 gigabytes/month

   Comparing to a cellular usage, we need to use smartphone consumption
   figures that precludes Wi-Fi as well as broadband specific fixed
   wireless access subscriptions.

   Using an example 10 gigabytes/month consumption per cellular
   subscription, it is evident that OpenRoaming bronze is dimensioned to
   accommodate 3.7 times the example cellular traffic, or 78% of total
   traffic when cellular and Wi-Fi are combined.  Similarly, OpenRoaming
   silver is dimensioned to carry 88% of total traffic when cellular and
   Wi-Fi are combined.

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8.2.3.  Privacy Policies

   The baseline privacy policy of OpenRoaming [ORPRIVACY] ensures the
   identities of end-users remain anonymous when using the service.  The
   WBA WRIX specification specifies that where supplicants use EAP
   methods that support user-name privacy, i.e., which are compatible
   with the "@realm" (or "anonymous@realm") (outer) EAP-Identifier, then
   the supplicant SHOULD use the anonymized outer EAP identifier.
   Supplicants supporting other EAP methods SHOULD support EAP method
   specific techniques for masking the end-user's permanent identifier,
   for example pseudonym support in EAP-AKA/AKA' [RFC4187] and/or
   enhanced IMSI privacy protection [WBAEIPP].  OpenRoaming IDPs SHOULD
   support and enable the corresponding server-side functionality to
   ensure end-user privacy is protected.

   The WBA WRIX specification also recognizes that the privacy of end-
   users can be unintentionally weakened by the use of correlation
   identifiers signalled using the Chargeable-User-Identity attribute
   (#89) [RFC4372] and/or the Class attribute (#25) [RFC2865] in the
   RADIUS Access-Accept packet.  The WBA WRIX Specification recommends
   that the default IDP policy SHOULD ensure that, when used, such
   correlation identifiers are unique for each combination of end-user/
   ANP and that the keys and/or initialization vectors used in creating
   such correlation identifiers SHOULD be refreshed at least every 48
   hours, but not more frequently than every 2 hours.

   This 2 hour limit is designed to assist the ANP in performing
   autonomous troubleshooting of connectivity issues from authentic end-
   users/devices that are repeatedly re-initiating connectivity to the
   ANP's network and/or to assist the ANP in identifying a new session
   originated by an authentic user/device that has previously been
   identified by the ANP as having violated the OpenRoaming end-user
   terms and conditions [ORTERMS].  When using typical public Wi-Fi
   session durations, it is estimated that, with this 2 hour
   restriction, the ANP will be able to correlate a RADIUS Access-
   Request/Access-Accept exchange that immediately follows a RADIUS
   Accounting-Request stop message in over 50% of the sessions.

   In contrast to this default policy, there can be scenarios where the
   ANP desires to derive value from its OpenRoaming settlement-free
   service by analysing aggregate end-user behaviour.  Whereas the use
   of aggregated end-user information does not violate the OpenRoaming
   privacy policy, the derivation of such can benefit from the ANP being
   able to uniquely identify end-users.  In order to support such
   scenarios, the OpenRoaming closed access group policies include the
   PID field.

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   The PID field can be used to support scenarios where the end-user has
   consented with their IDP that an immutable end-user identifier can be
   signalled to the ANP in the RADIUS Access-Accept.  The format of the
   PID field is illustrated in Figure 8.  The PID field can be
   configured to "1" in the RCOIs used by those ANPs that want to be be
   able to account for unique OpenRoaming end-users.

   The OpenRoaming IDP terms [ORTERMS] ensure subscribers MUST
   explicitly give their permission before an immutable end-user
   identity is shared with a third party ANP.  When such permission has
   not been granted, an IDP MUST NOT set the PID field to "1" in any of
   the RCOIs in its end-user Passpoint profiles.  When such permission
   has been granted, an IDP MAY configure multiple RCOIs in their end-
   users' Passpoint profile, including RCOIs with the PID field set to
   "1".

   +-----------------------------------------------------------+
   |  PID Field  |                 Description                 |
   +-----------------------------------------------------------+
   |     B4      |                                             |
   +-----------------------------------------------------------+
   |     0       |   Baseline ID Policy applies, i.e., users   |
   |             |   remain anonymous whilst using the service.|
   +-----------------------------------------------------------+
   |     1       |   An immutable end-user ID will be returned |
   |             |   by the IDP in the Access-Accept packet.   |
   +-----------------------------------------------------------+

                    Figure 8: OpenRoaming CAG PID Field

8.2.4.  ID-Type Policies

   The ID-Type field can be used to realize policies which are based on
   the business sector associated with the identity used by the IDP.
   The format of the ID-Type field is illustrated in Figure 9.

   All IDPs configure at least one RCOI in their end-user's Passpoint
   profile with ID-Type set to "0000" (Any identity type is permitted).
   An IDP MAY configure additional RCOIs in their end-users' Passpoint
   profile with an ID-Type representing the sector type of IDP.

   An ANP what wants to serve all end-users, irrespective of sector,
   configures RCOIs in the WLAN equipment with ID-Type set to "0000".
   Alternatively, an ANP which operates a sector specific business that
   only desires to serve a subset of OpenRoaming end-users MAY set the
   ID-Type to their desired sector in all configured RCOIs.

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   +-----------------------------------------------------------+
   |       ID-Type Field       |           Description         |
   +-----------------------------------------------------------+
   |  B3  |  B2  |  B1  |  B0  |                               |
   +-----------------------------------------------------------+
   |  0   |  0   |  0   |  0   | Any identity type is permitted|
   +-----------------------------------------------------------+
   |  0   |  0   |  0   |  1   | A service provider identity   |
   +-----------------------------------------------------------+
   |  0   |  0   |  1   |  0   | A cloud provider identity     |
   +-----------------------------------------------------------+
   |  0   |  0   |  1   |  1   | A generic enterprise identity |
   +-----------------------------------------------------------+
   |  0   |  1   |  0   |  0   | A government identity, e.g.,  |
   |      |      |      |      | including city                |
   +-----------------------------------------------------------+
   |  0   |  1   |  0   |  1   | An automotive identity        |
   +-----------------------------------------------------------+
   |  0   |  1   |  1   |  0   | A hospitality identity        |
   +-----------------------------------------------------------+
   |  0   |  1   |  1   |  1   | An aviation industry identity |
   +-----------------------------------------------------------+
   |  1   |  0   |  0   |  0   | An education or research      |
   |      |      |      |      | identity                      |
   +-----------------------------------------------------------+
   |  1   |  0   |  0   |  1   | A cable industry identity     |
   +-----------------------------------------------------------+
   |  1   |  0   |  1   |  0   | A manufacturer identity       |
   |      |      |      |      | (note 1)                      |
   +-----------------------------------------------------------+
   |  1   |  0   |  1   |  1   | A retail identity             |
   +-----------------------------------------------------------+
   |        other values       | Reserved                      |
   +-----------------------------------------------------------+
   | NOTE 1: A manufacturer identity closed access group policy|
   | applies to IoT credentials corresponding to manufacturer  |
   | installed identities as well as IoT credentials           |
   | corresponding to owner installed identities.              |
   +-----------------------------------------------------------+

                  Figure 9: OpenRoaming CAG ID-Type Field

8.2.5.  On-boarding Credential Policies

   The format of the on-boarding credential policy (On-board) field is
   as shown in Figure 10.

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   +-----------------------------------------------------------+
   | On-board Field  |               Description               |
   +-----------------------------------------------------------+
   |  B7 Octet 5     |                                         |
   +-----------------------------------------------------------+
   |     0           |   A long-lived identity                 |
   +-----------------------------------------------------------+
   |     1           |   A short-lived identity                |
   +-----------------------------------------------------------+

                 Figure 10: OpenRoaming CAG On-board Field

   The On-board field is used to identify closed access group policy
   aspects related to whether the identity/profile is long-lived, or
   whether the identity/profile is short-lived.  Short-lived profiles
   are intended to only be used to provide connectivity such that the
   procedure for configuring a long-lived identity/profile can be
   performed.

   Sessions authorized with short-lived credentials MUST have a session-
   timeout value of less than 300 seconds.

8.3.  Prioritizing Policies

   The definition of OpenRoaming closed access group policies assumes
   the configuration of multiple RCOIs in ANP WLAN equipment and IDP
   end-user devices.

   When a device has multiple Passpoint profiles matching the ANP's
   Closed Access Group policy, an OpenRoaming ANP may want to prefer
   OpenRoaming subscribers use a particular IDP's profile when attaching
   to its access network.  Such a preference can be because the
   OpenRoaming ANP has a preferential relationship with certain
   OpenRoaming IDPs.

   The OpenRoaming ANP is able to use the Home SP preference
   functionality defined in Passpoint [PASSPOINT] to prioritize the use
   of a particular profile by a Passpoint enabled device.  In such a
   scenario, the ANP configures the Domain Name list to include the
   FQDN(s) associated with the profile(s) to be prioritized.

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9.  OpenRoaming RADIUS Profile

   The OpenRoaming RADIUS profile is based on the WBA WRIX Specification
   which in turn are derived from [RFC3580] and [RFC3579].  All ANPs
   MUST support RADIUS Accounting for all OpenRoaming sessions,
   irrespective of which RCOIs are supported, i.e., for both settled and
   settlement free service.  All IDPs MUST respond to any RADIUS Access-
   Request and Accounting-Request packet received.

   Additionally, OpenRoaming defines the use of the following RADIUS
   attributes.

9.1.  Operator-Name

   As described in Section 4, OpenRoaming uses the Operator-Name (#126)
   [RFC5580] attribute to signal the WBAID of the OpenRoaming ANP.  All
   ANPs MUST support the Operator-Name attribute and use it to signal
   the WBAID of the OpenRoaming ANP, using the WBA allocated Operator
   Namespace identifier, as specified in Section 4.

   Exceptionally, if the RADIUS client does not support the WBA
   allocated namespace identifier, the WBAID MAY be encoded in the realm
   namespace, by using the base64 encoded [RFC4648] WBAID as a subdomain
   to the realm "wballiance.com".  For example,

      ANP1.INTERMEDIARY2:PT

   is encoded as

      QU5QMS5JTlRFUk1FRElBUlkyOlBU.wballiance.com

9.2.  Chargeable-User-Identity

   All OpenRoaming ANPs MUST support the Chargeable-User-Identity
   attribute (#89) [RFC4372] and indicate such by including a CUI
   attribute in all RADIUS Access-Request packets.  An ANP that has
   configured the OpenRoaming-Context PID Field set to "1" MAY treat a
   RADIUS Access-Accept received without a CUI attribute as an Access-
   Reject.  An ANP that has configured the OpenRoaming-Context PID Field
   set to "0" MUST NOT treat any RADIUS Access-Accept received without a
   CUI attribute as an Access-Reject.

   When an end-user has explicitly given their permission to share an
   immutable end-user identifier with third party ANPs, the CUI returned
   by the IDP MUST be invariant over subsequent end-user authentication
   exchanges between the IDP and the ANP.

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9.3.  Location-Data/Location-Information

   All OpenRoaming ANPs MUST support signalling of location information
   using [RFC5580].  As a minimum, all OpenRoaming IDPs need to be able
   to determine the country in which the OpenRoaming ANP operates.  The
   OpenRoaming legal framework described in Appendix C serves as an
   "out-of-band agreement" as specified in clause 3.1 of [RFC5580].
   Hence, all OpenRoaming ANPs MUST include the Location-Data attribute
   (#128) in the RADIUS Access-Request packet, where the location
   profile is the civic location profile that includes the country code
   where the ANP is located [RFC5580].

   When the OpenRoaming ANP supports the OpenRoaming-Settled RCOI ("BA-
   A2-D0"), the RADIUS Access-Request packet MUST include the Location-
   Data attribute (#128) where the location profile is the civic
   location profile containing Civic Address Type information that is
   sufficient to identify the financial regulatory regime that defines
   the taxable rates associated with consumption of the ANP's service.

   OpenRoaming also defines the optional use the geospatial location
   profile as specified in [RFC5580].  ANPs MAY signal coordinate-based
   geographic location of the NAS or end-user device.

   The OpenRoaming Privacy Policy [ORPRIVACY] restricts the use of all
   location information signalled to an IDP for either:

   1.  Making service authorization decisions based on the location of
       the ANP's wireless network; or

   2.  Compliance with applicable law, or law enforcement requests.

9.4.  Session-Timeout

   An OpenRoaming ANP receiving a RADIUS Access Accept message including
   a Session-Timeout attribute MUST operate according to [RFC3580].

   An IDP authenticating using a credential associated with a Passpoint
   profile with an RCOI where the On-board value is set to 1, as defined
   in Section 8.2.5, MUST set the session-timeout value to less than 300
   seconds in the RADIUS Access-Accept message.

9.5.  Acct-Session-Id

   All OpenRoaming enabled ANPs MUST support attribute Acct-Session-Id
   [RFC2866].  If an OpenRoaming IDP receives a RADIUS Access-Request
   message without an Acct-Session-Id attribute, it SHOULD reject the
   Access-Request.

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   When supported, the Acct-Session-Id attribute SHOULD be temporally
   unique within an ANP's access network.

   An OpenRoaming IDP that receives a RADIUS Accounting-Request message
   without either an Acct-Session-Id or an Acct-Multi-Session-Id
   corresponding to an authenticated RADIUS session SHOULD create a log
   of the message non-compliance, including the WBAID of the ANP.

9.6.  Acct-Multi-Session-Id

   All OpenRoaming enabled ANPs configured to generate multiple related
   accounting sessions for a single EAP-Supplicant roaming between Wi-Fi
   Access points MUST support attribute Acct-Multi-Session-Id [RFC2866].

   The Acct-Multi-Session-Id attribute SHOULD be temporally unique
   within an ANP's access network.

   An OpenRoaming IDP that receives a RADIUS Accounting-Request message
   without either an Acct-Session-Id or an Acct-Multi-Session-Id
   corresponding to an authenticated RADIUS session SHOULD create a log
   of the message non-compliance, including the WBAID of the ANP.

9.7.  Event-Timestamp

   All OpenRoaming ANPs MUST include the Event-Timestamp attribute
   [RFC2869] in all RADIUS Accounting-Request messages.

9.8.  Connect-Info

   An OpenRoaming ANP MAY include the RADIUS Connect-Info (#77)
   attribute in RADIUS messages sent to an IDP, as specified in
   [RFC2869].  When included, the ANP SHOULD use the syntax defined in
   [I-D.draft-grayson-connectinfo] to signal Wi-Fi network connection
   metrics to an OpenRoaming IDP.  An IDP authenticating an OpenRoaming
   end-user MAY use the information signalled in the Connect-Info
   attribute when making authorization decisions.

   The ANP MAY use the enhanced Connect-Info syntax to signal real-time
   information, including:

   *  transmit and receive bit rates,

   *  received signal strength indicator (RSSI),

   *  frame loss rate,

   *  frame retry rate, and

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   *  the Wi-Fi global operating class(es) associated with the
      connection, as defined in Annex E of [IEEE80211].

   When supported by the ANP, these quality metrics SHOULD be included
   in both RADIUS Access-Request and RADIUS Accounting-Request messages.
   The OpenRoaming legal framework (see Appendix C) ensures that IDPs
   that do not separately agree to terms with an ANP governing use of
   Wi-Fi network connection metrics MUST solely process signaled
   performance data for the purposes of making service authorization
   decisions and network troubleshooting, and are prohibited from
   disclosing such data to any third party except as necessary for
   direct network troubleshooting with the originating ANP.

   When included in the RADIUS Access-Request and initial RADIUS
   Accounting-Request message, because the raw samples used to calculate
   the metrics will be restricted by the number of IEEE 802.11 frames
   over which the calculation are based, the transmit bit rates, receive
   bit rates and RSSI level MAY correspond to the instantaneous value of
   the specific parameter.

   In other cases, i.e., where the Connect-Info attribute is signaled in
   RADIUS Accounting-Request messages with Acct-Status-Type set to
   Interim-Update or Stop, the ANP SHOULD use multiple measurements when
   calculating the reported value:

   *  the reported transmit and receive bit rates SHOULD represent the
      maximum values experienced since the last time the connect-info
      was signaled, i.e. the "ALGO" term SHOULD be set to "MAX".

   *  the received signal strength indicator (RSSI) SHOULD represent the
      average RSSI value, where the average value calculated MAY be
      either a linear average or an exponential weighted average, i.e.
      the "ALGO" term SHOULD be set to "AVG".

   *  frame loss rate and frame retry rate SHOULD represent the
      accumulated ratio, i.e. the "ALGO" term SHOULD be set to "ACC".

9.9.  Enhanced Reply-Message

   Reply-Message was originally defined in [RFC3579] as being forbidden
   from being included in any RADIUS message containing an EAP-Message
   attribute.  This was to prevent earlier systems from attempting to
   interwork the Reply-Message text into an EAP Notification packet.

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   In contrast to using Reply-Message to signal a displayable text
   string to authenticating users, WBA's WRIX framework defines the re-
   use of the attribute in WRIX-based Passpoint networks to signal
   additional information from the IDP to the ANP, specifically
   regarding why a connection has been rejected.  The message received
   MUST NOT be shown to end-users.

   The enhanced reply-message is encoded using UTF-8 characters.  The
   WBA defines additional information is appended after the NUL ASCII
   character (0x00).  The ABNF syntax of the Reply-Message is shown in
   Figure 11.

   Reply-message      = [ displayable-string ] %x00 [ wba-info ]
   displayable-string = *CHAR
   wba-info           =  "Reject-Reason=" cause-code

   cause-code =  "10" ; failed user authentication
   cause-code =/ "11" ; invalid user identity
   cause-code =/ "12" ; expired client certificate
   cause-code =/ "20" ; generic AAA failure
   cause-code =/ "21" ; backend failure
   cause-code =/ "22" ; protocol timeout
   cause-code =/ "30" ; failure due to badly formatted request
   cause-code =/ "31" ; rejected - missing charging model
   cause-code =/ "32" ; rejected - missing geospatial location
   cause-code =/ "40" ; failure due to subscription - permanent
   cause-code =/ "41" ; authorization rejected - no service
                      ; subscription
   cause-code =/ "42" ; authorization rejected - roaming not
                      ; allowed in this network
   cause-code =/ "43" ; authorization rejected - offered charging
                      ; model not acceptable
   cause-code =/ "44" ; authorization rejected - roaming to this
                      ; location not allowed
   cause-code =/ "45" ; authorization rejected - offered service
                      ; level not acceptable
   cause-code =/ "50" ; failure due to subscription - temporary
   cause-code =/ "51" ; authorization rejected - offered charging
                      ; model not acceptable at this time
   cause-code =/ "52" ; authorization rejected - roaming to this
                      ; location not allowed at this time
   cause-code =/ "53" ; authorization rejected - concurrency
                      ; limits exceeded
   cause-code =/ "54" ; authorization rejected - insufficient
                      ; credit

                Figure 11: WBA Enhanced Reply-Message Syntax

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9.10.  WBA-Identity-Provider

   The Operator-Name attribute allows the WBAID of the ANP to be
   signalled to the IDP.  In the reverse direction, the IDP MUST use the
   WBA-Identity-Provider vendor specific attribute [WBAVSA] to signal
   the WBAID of the IDP back to the ANP.  In this case the first
   character of the Identity-Provider attribute identifies the WBAID
   namespace and is equal to "4" (0x34).

9.11.  WBA-Offered-Service

   The ANP MAY use the WBA-Offered-Service vendor specific attribute to
   signal the highest OpenRoaming service tier supported on its network
   [WBAVSA].

   If a RADIUS Access-Request is received without either a WBA-Offered-
   Service or WBA-Custom-SLA attribute, the IDP SHOULD assume that the
   authorization request is associated with the OpenRoaming Bronze
   service.

9.12.  WLAN-Venue-Info

   The ANP MAY use the WLAN-Venue-Info attribute [RFC7268] to signal the
   category of venue hosting the WLAN.

9.13.  WBA-Custom-SLA

   When the ANP uses the WLAN-Venue-Info attribute to signal that the
   venue hosting the WLAN is a vehicular installation, the ANP SHOULD
   use the WBA-Custom-SLA vendor specific attribute [WBAVSA] to indicate
   one or more (availability, per-user sustained bandwidth) tuples to
   the IDP.

9.14.  Filter-Id

   If the IDP accepts the offered service corresponding to the WBA-
   Offered-Service attribute, then it MUST copy the contents of the text
   string received in the WBA-Offered-Service attribute and include the
   same text string in a RADIUS Filter-Id attribute returned in the
   Access-Accept message.

   If the IDP accepts the offered service corresponding to the WBA-
   Custom-SLA attribute, then the IDP shall include the text string
   "OpenRoaming Custom" in the RADIUS Filter-Id attribute returned in
   the RADIUS Access-Accept message.

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9.15.  Operator-NAS-Identifier

   An OpenRoaming ANP supporting the Reverse CoA functionality defined
   in Section 9.16, MAY use the Operator-NAS-Identifier (#241.8) as
   specified in [RFC8559].  When received by the IDP, the Operator-NAS-
   Identifier attribute MUST be stored along with any end-user session
   identification attributes.  When sending a CoA packet for an end-user
   session, the IDP MUST include verbatim any Operator-NAS-Identifier it
   has recorded for that session.

9.16.  Reverse Change of Authorization

   The connection management procedures described in Section 7 ensure
   that an ANP supporting Reverse CoA is reachable from an IDP whenever
   an IDP's OpenRoaming user is active on an ANP's OpenRoaming wireless
   network.  This reachability allows the IDP, or its authorized hub, to
   send a Change of Authorization (CoA) request packet to the ANP in
   "reverse" over the existing TLS connection, and for the ANP to send
   responses towards the message originator.

   *  ANPs and hubs supporting OpenRoaming settled SHOULD support the
      Reverse CoA in RADIUS/TLS defined in
      [I-D.draft-ietf-radext-reverse-coa].

   *  IDPs supporting OpenRoaming settled operation MAY support the
      Reverse CoA in RADIUS/TLS defined in
      [I-D.draft-ietf-radext-reverse-coa], where the CoA refers to
      either the CoA-Request or Disconnect-Request messages as defined
      in [RFC5176].

   There is no explicit negotiation of support for Reverse CoA between
   OpenRoaming ANPs, hubs and IDPs.

   An IDP supporting Reverse CoA SHOULD interpret the lack of response
   to a CoA-Request or Disconnect-Request as being due to the silent
   discard of the packet by an un-supporting ANP, or an intermediate
   hub.  The CoA originator SHOULD associate the reverse CoA capability
   with each ANP, as identified by the Operator-Name attribute (#126).
   The CoA originator that has identified an un-supporting ANP SHOULD
   cease sending further Reverse CoA requests to that ANP.

   IDPs and hubs supporting Reverse CoA MUST be able to forward the CoA
   packet to the correct next hop based on the TLS session used to
   support the user-session.  When load balancing is employed, the
   routing of reverse CoA packets MUST account for the possibility that
   multiple CoA servers can be associated with the same Operator-Name
   attribute:

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   *  The IDP and hub MUST maintain session affinity or "stickiness" to
      the specific TLS session corresponding to the user session, so
      that CoA packets are routed to the same server instance that
      established the original session.

   *  The routing logic SHOULD use additional session identification
      attributes, such as Charegable-User-Id, Acct-Session-Id, Operator-
      Name, Called-Station-Id and/or Operator-NAS-Identifier, to
      disambiguate among multiple possible next hops when load balancing
      is in effect.

   *  If multiple TLS sessions exist for the same WBAID due to load
      balancing, the IDP SHOULD select the appropriate next hop based on
      the user session context to avoid routing CoA packets to an
      incorrect CoA server.

   *  The CoA packet is sent to the next proxy/CoA Server according to
      the routing logic.  This process continues with any subsequent
      proxies until the packet reaches the ANP's CoA server.

   IDPs MUST include the Operator-Name attribute in all CoA-Request and
   Disconnect-Request packets, as described in [RFC8559].  The value of
   the Operator-Name attribute MUST be the value that was recorded
   earlier for that user session.

   If a proxy/CoA Server receives a CoA packet with an unknown Operator-
   Name, the server MUST operate as per [RFC8559] and return a NAK
   packet that contains an Error-Cause Attribute having value 502
   ("Request Not Routable").

   The ANP MAY use the Operator-NAS-Identifier as specified in
   [RFC8559].  When received by the IDP, the Operator-NAS-Identifier
   attribute MUST be stored along with any user session identification
   attributes.  When sending a CoA packet for a user session, the IDP
   MUST include verbatim any Operator-NAS-Identifier it has recorded for
   that session.

9.17.  Additional Attributes Related to OpenRoaming Settled

   OpenRoaming settled defines the use of additional RADIUS attributes.

9.17.1.  WBA-Financial-Clearing-Provider

   All OpenRoaming ANPs and IDPs that support the OpenRoaming settled
   service MUST use the WBA-Financial-Clearing-Provider vendor specific
   attribute to signal the identity of the provider of financial
   clearing services [WBAVSA].

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9.17.2.  WBA-Data-Clearing-Provider

   All OpenRoaming ANPs and IDPs that support the OpenRoaming settled
   service MAY use the WBA-Data-Clearing-Provider vendor specific
   attribute to signal the identity of the provider of data clearing
   services [WBAVSA].

9.17.3.  WBA-Linear-Volume-Rate

   In cellular roaming, inter-operator tariff information is exchanged
   in the roaming agreements between operators.  In OpenRoaming, as
   there is no direct agreement between ANPs and IDPs, the tariff
   information is exchanged in RADIUS messages.  All OpenRoaming ANPs
   that support the OpenRoaming settled service MUST use the WBA-Linear-
   Volume-Rate vendor specific attribute to signal the charging model
   being offered by the ANP [WBAVSA].  An IDP that authorizes an offered
   charging model MUST include the agreed WBA-Linear-Volume-Rate in the
   Access-Accept packet.

9.17.4.  OpenRoaming Session Mediation

   OpenRoaming-Settled necessarily requires end-entities, which may
   include ANPs, IDPs and/or their respective hub-providers, to be able
   to perform session mediation between RADIUS Access-Request/Access-
   Accept and RADIUS Accounting-Request messages.  This can be performed
   using RADIUS attributes Acct-Session-Id (#44) and Acct-Multi-Session-
   Id (#50) together with Operator-Name (#126).

   To allow for possible non-uniqueness of Acct-Session-Id and/or Acct-
   Multi-Session-Id attributes between different Network Access Servers
   (NAS) within the same ANP, it is recommended to additionally use the
   attribute NAS-Identifier (#32) or NAS-IP-Address (#4) or NAS-
   IPv6-Address (#95) or Called-Station-Id (#30) in the matching
   process.

10.  Security Considerations

10.1.  Network Selection and Triggering Authentication

   OpenRoaming defines the use of Passpoint with Roaming Consortium
   Organization Identifiers.  A bit-wise match between an RCOI
   configured in the Passpoint profile of an end-user's device and the
   RCOI signalled by WLAN equipment will trigger a Passpoint defined
   EAP-based authentication exchange.  The security associated with the
   Passpoint RCOI information element is identical to other PLMN Id and
   Realm information elements, allowing an unauthorized system to
   configure the OpenRoaming RCOI with the aim of triggering a Passpoint
   authentication.  Because such an unauthorized system will not have

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   been issued with a certificate from WBA's PKI, the unauthorized
   system is unable to communicate with any other OpenRoaming provider.
   In such a scenario, after successive multiple failed authentications,
   the device's supplicant SHOULD add the Access Point's BSSID to a deny
   list to avoid future triggering of an authentication exchange with
   the unauthorized system.

10.2.  ANP RadSec Connectivity

   The ANP's RadSec client connects to the IDP's RadSec server over the
   public Internet.  Recommended best practice for firewall deployment
   on public Internet facing interfaces SHOULD be followed.  Firewall
   rules SHOULD permit outbound RadSec traffic (TCP destination port
   2083) and allow return traffic for the same TCP connections while
   denying any TCP socket initiation from outside of the ANP's network.

10.3.  Dynamic Discovery of RadSec Peers

   Whereas the dynamic discovery mechanisms specified in [RFC7585]
   permit the IDP to use their DNS SRV record to indicate a non-standard
   TCP port to be used in a RadSec connection, IDPs SHOULD recognize
   that ANP systems may only be configured to permit outbound
   connections on the standardized RadSec port of 2083.

   OpenRoaming recommends the use of DNSSEC to ensure a dynamically
   discovered RadSec server is authoritative for a particular realm or
   set of realms.  Where this is not possible, e.g., when using dynamic
   resolution with the pub.3gppnetwork.org sub-domain, the OpenRoaming
   certificate policy [WBAPKICP] permits the configuration of supported
   realm(s) in the SubjectAltName of the certificate(s) issued to the
   IDP.

   An ANP MAY decide to continue with the RadSec establishment, even if
   a server cannot prove it is authoritative for a realm.  As the ANP's
   RadSec client uses a dedicated trust store corresponding to the WBA's
   private Certificate Authority, if DNS is hijacked by a third-party
   non-federation member who has not been issued a certificate under
   WBA's PKI, the subsequent TLS establishment will fail.

   In order to prevent denial of service/brute force attacks, IDPs
   SHOULD implement intrusion prevention functionality that monitors
   systems to identify TLS mutual authentication failures.  Monitoring
   SHOULD identify source IP addresses that are causing repeated TLS
   authentication failures and use firewall functionality to temporarily
   block packets from those source IP addresses

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10.4.  End-User Traffic

   The OpenRoaming federation ensures RADIUS traffic is secured between
   ANP and IDP and ensures Wi-Fi traffic is protected between the end-
   user device and the WLAN equipment of the ANP.  The ANP is therefore
   able to observe IP traffic to/from end-users who have performed a
   successful authentication with their IDP.  The OpenRoaming legal
   framework (see Appendix C) ensures that the ANP has agreed to the
   OpenRoaming Privacy Policy [ORPRIVACY] to correctly handle the
   personally identifiable information collected as part of providing
   the ANP service.

   The Open-Roaming end-user terms and conditions [ORTERMS] ensure that
   end-users are aware that the federation does not provide a secure
   end-to-end service.  The end-user MUST NOT rely on the encryption
   delivered by OpenRoaming for providing security of services accessed
   using the ANP's Wi-Fi network.

10.5.  ANP Inspection of End-User Traffic

   All OpenRoaming ANPs MUST implement layer 2 traffic inspection and
   filtering, as specified in clause 5.1 of the [PASSPOINT]
   specification.  ANPs MUST prohibit the delivery of any packet
   received from an OpenRoaming device directly to another OpenRoaming
   end-user device.

   All ANPs MUST use traffic inspection and filtering to help protect
   OpenRoaming users from malicious activity on the Internet as well as
   possible malicious activity by other authenticated OpenRoaming users.
   ANP traffic filtering function SHOULD NOT block ports associated with
   Wi-Fi calling, including UDP ports 500 and 4500 used by Internet Key
   Exchange (IKE), Internet Security Association and Key Management
   Protocol (ISAKMP) and IPSec [RFC7296].  Recommended best practice for
   firewall deployment on public Internet facing interfaces SHOULD be
   followed, including configuring the traffic inspection and filtering
   using information derived from reliable sources of threat
   intelligence.

10.6.  End-User Location

   The OpenRoaming legal framework (see Appendix C) ensures that the IDP
   has agreed to the OpenRoaming Privacy Policy [ORPRIVACY] to correctly
   handle the location-based personally identifiable information
   collected as part of providing the IDP service.  Unless the IDP has
   agreed a separate privacy policy with the end-user, the IDP MUST only
   use location information signalled by an ANP for either:

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   1.  Making service authorization decisions based on the location of
       the ANP's wireless network; or

   2.  Compliance with applicable law, or law enforcement requests.

11.  Future Enhancements

   WBA announced the launch of its OpenRoaming Federation in June 2020.
   Since then, WBA members have continued to enhance the technical
   framework to address new market requirements.  WBA encourages those
   parties interested in adapting OpenRoaming to address new
   opportunities and use-cases to join the Alliance and help drive the
   definition of OpenRoaming forward.

12.  IANA Considerations

   This document has no IANA actions.

13.  References

13.1.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/rfc/rfc2119>.

   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <https://www.rfc-editor.org/rfc/rfc8174>.

13.2.  Informative References

   [E212]     ITU-T Study Group 2, "The international identification
              plan for public networks and subscriptions", June 2024,
              <https://www.itu.int/itu-t/recommendations/
              rec.aspx?rec=E.212>.

   [GSMAIR67] GSMA, "GSMA IR.67: DNS Guidelines for Service Providers
              and GRX and IPX Providers", 25 November 2022,
              <https://www.gsma.com/newsroom/wp-content/
              uploads//IR.67-v21.0.pdf>.

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   [I-D.draft-grayson-connectinfo]
              Grayson, M. and J. Redmore, "A syntax for the RADIUS
              Connect-Info attribute used in Wi-Fi networks", Work in
              Progress, Internet-Draft, draft-grayson-connectinfo-09, 19
              May 2026, <https://datatracker.ietf.org/doc/html/draft-
              grayson-connectinfo-09>.

   [I-D.draft-ietf-radext-reverse-coa]
              DeKok, A. and V. Cargatser, "Reverse Change-of-
              Authorization (CoA) in RADIUS/(D)TLS", Work in Progress,
              Internet-Draft, draft-ietf-radext-reverse-coa-08, 27
              August 2025, <https://datatracker.ietf.org/doc/html/draft-
              ietf-radext-reverse-coa-08>.

   [I-D.ietf-radext-radiusdtls-bis]
              Rieckers, J., Cullen, M., and S. Winter, "RadSec: RADIUS
              over Transport Layer Security (TLS) and Datagram Transport
              Layer Security (DTLS)", Work in Progress, Internet-Draft,
              draft-ietf-radext-radiusdtls-bis-16, 5 May 2026,
              <https://datatracker.ietf.org/doc/html/draft-ietf-radext-
              radiusdtls-bis-16>.

   [IEEE80211]
              IEEE, "Wireless LAN Medium Access Control (MAC) and
              Physical Layer (PHY) Specifications", n.d.,
              <https://standards.ieee.org/ieee/802.11/5536/>.

   [ISO3166]  ISO 3166-2:2020, "Codes for the representation of names of
              countries and their subdivisions", August 2020,
              <https://www.iso.org/standard/72483.html>.

   [ISO29115] ISO/IEC 29115, "Information technology - Security
              techniques: Entity authentication assurance framework",
              April 2013.

   [ORPRIVACY]
              Wireless Broadband Alliance, "OpenRoaming End-User Privacy
              Policy", n.d.,
              <https://wballiance.com/openroaming/privacy-policy/>.

   [ORTERMS]  Wireless Broadband Alliance, "OpenRoaming End User Terms
              and Conditions", n.d.,
              <https://wballiance.com/openroaming/toc/>.

   [PASSPOINT]
              Wi-Fi Alliance, "Wi-Fi Alliance Passpoint", n.d.,
              <https://www.wi-fi.org/discover-wi-fi/passpoint>.

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   [PEAP]     Microsoft Corporation, "Protected Extensible
              Authentication Protocol (PEAP)", April 2024,
              <https://winprotocoldocs-bhdugrdyduf5h2e4.b02.azurefd.net/
              MS-PEAP/%5bMS-PEAP%5d.pdf>.

   [RFC2865]  Rigney, C., Willens, S., Rubens, A., and W. Simpson,
              "Remote Authentication Dial In User Service (RADIUS)",
              RFC 2865, DOI 10.17487/RFC2865, June 2000,
              <https://www.rfc-editor.org/rfc/rfc2865>.

   [RFC2866]  Rigney, C., "RADIUS Accounting", RFC 2866,
              DOI 10.17487/RFC2866, June 2000,
              <https://www.rfc-editor.org/rfc/rfc2866>.

   [RFC2869]  Rigney, C., Willats, W., and P. Calhoun, "RADIUS
              Extensions", RFC 2869, DOI 10.17487/RFC2869, June 2000,
              <https://www.rfc-editor.org/rfc/rfc2869>.

   [RFC3579]  Aboba, B. and P. Calhoun, "RADIUS (Remote Authentication
              Dial In User Service) Support For Extensible
              Authentication Protocol (EAP)", RFC 3579,
              DOI 10.17487/RFC3579, September 2003,
              <https://www.rfc-editor.org/rfc/rfc3579>.

   [RFC3580]  Congdon, P., Aboba, B., Smith, A., Zorn, G., and J. Roese,
              "IEEE 802.1X Remote Authentication Dial In User Service
              (RADIUS) Usage Guidelines", RFC 3580,
              DOI 10.17487/RFC3580, September 2003,
              <https://www.rfc-editor.org/rfc/rfc3580>.

   [RFC3748]  Aboba, B., Blunk, L., Vollbrecht, J., Carlson, J., and H.
              Levkowetz, Ed., "Extensible Authentication Protocol
              (EAP)", RFC 3748, DOI 10.17487/RFC3748, June 2004,
              <https://www.rfc-editor.org/rfc/rfc3748>.

   [RFC4187]  Arkko, J. and H. Haverinen, "Extensible Authentication
              Protocol Method for 3rd Generation Authentication and Key
              Agreement (EAP-AKA)", RFC 4187, DOI 10.17487/RFC4187,
              January 2006, <https://www.rfc-editor.org/rfc/rfc4187>.

   [RFC4372]  Adrangi, F., Lior, A., Korhonen, J., and J. Loughney,
              "Chargeable User Identity", RFC 4372,
              DOI 10.17487/RFC4372, January 2006,
              <https://www.rfc-editor.org/rfc/rfc4372>.

   [RFC4648]  Josefsson, S., "The Base16, Base32, and Base64 Data
              Encodings", RFC 4648, DOI 10.17487/RFC4648, October 2006,
              <https://www.rfc-editor.org/rfc/rfc4648>.

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   [RFC4851]  Cam-Winget, N., McGrew, D., Salowey, J., and H. Zhou, "The
              Flexible Authentication via Secure Tunneling Extensible
              Authentication Protocol Method (EAP-FAST)", RFC 4851,
              DOI 10.17487/RFC4851, May 2007,
              <https://www.rfc-editor.org/rfc/rfc4851>.

   [RFC5176]  Chiba, M., Dommety, G., Eklund, M., Mitton, D., and B.
              Aboba, "Dynamic Authorization Extensions to Remote
              Authentication Dial In User Service (RADIUS)", RFC 5176,
              DOI 10.17487/RFC5176, January 2008,
              <https://www.rfc-editor.org/rfc/rfc5176>.

   [RFC5280]  Cooper, D., Santesson, S., Farrell, S., Boeyen, S.,
              Housley, R., and W. Polk, "Internet X.509 Public Key
              Infrastructure Certificate and Certificate Revocation List
              (CRL) Profile", RFC 5280, DOI 10.17487/RFC5280, May 2008,
              <https://www.rfc-editor.org/rfc/rfc5280>.

   [RFC5448]  Arkko, J., Lehtovirta, V., and P. Eronen, "Improved
              Extensible Authentication Protocol Method for 3rd
              Generation Authentication and Key Agreement (EAP-AKA')",
              RFC 5448, DOI 10.17487/RFC5448, May 2009,
              <https://www.rfc-editor.org/rfc/rfc5448>.

   [RFC5580]  Tschofenig, H., Ed., Adrangi, F., Jones, M., Lior, A., and
              B. Aboba, "Carrying Location Objects in RADIUS and
              Diameter", RFC 5580, DOI 10.17487/RFC5580, August 2009,
              <https://www.rfc-editor.org/rfc/rfc5580>.

   [RFC5997]  DeKok, A., "Use of Status-Server Packets in the Remote
              Authentication Dial In User Service (RADIUS) Protocol",
              RFC 5997, DOI 10.17487/RFC5997, August 2010,
              <https://www.rfc-editor.org/rfc/rfc5997>.

   [RFC6066]  Eastlake 3rd, D., "Transport Layer Security (TLS)
              Extensions: Extension Definitions", RFC 6066,
              DOI 10.17487/RFC6066, January 2011,
              <https://www.rfc-editor.org/rfc/rfc6066>.

   [RFC6071]  Frankel, S. and S. Krishnan, "IP Security (IPsec) and
              Internet Key Exchange (IKE) Document Roadmap", RFC 6071,
              DOI 10.17487/RFC6071, February 2011,
              <https://www.rfc-editor.org/rfc/rfc6071>.

   [RFC6614]  Winter, S., McCauley, M., Venaas, S., and K. Wierenga,
              "Transport Layer Security (TLS) Encryption for RADIUS",
              RFC 6614, DOI 10.17487/RFC6614, May 2012,
              <https://www.rfc-editor.org/rfc/rfc6614>.

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   [RFC7170]  Zhou, H., Cam-Winget, N., Salowey, J., and S. Hanna,
              "Tunnel Extensible Authentication Protocol (TEAP) Version
              1", RFC 7170, DOI 10.17487/RFC7170, May 2014,
              <https://www.rfc-editor.org/rfc/rfc7170>.

   [RFC7268]  Aboba, B., Malinen, J., Congdon, P., Salowey, J., and M.
              Jones, "RADIUS Attributes for IEEE 802 Networks",
              RFC 7268, DOI 10.17487/RFC7268, July 2014,
              <https://www.rfc-editor.org/rfc/rfc7268>.

   [RFC7296]  Kaufman, C., Hoffman, P., Nir, Y., Eronen, P., and T.
              Kivinen, "Internet Key Exchange Protocol Version 2
              (IKEv2)", STD 79, RFC 7296, DOI 10.17487/RFC7296, October
              2014, <https://www.rfc-editor.org/rfc/rfc7296>.

   [RFC7585]  Winter, S. and M. McCauley, "Dynamic Peer Discovery for
              RADIUS/TLS and RADIUS/DTLS Based on the Network Access
              Identifier (NAI)", RFC 7585, DOI 10.17487/RFC7585, October
              2015, <https://www.rfc-editor.org/rfc/rfc7585>.

   [RFC7593]  Wierenga, K., Winter, S., and T. Wolniewicz, "The eduroam
              Architecture for Network Roaming", RFC 7593,
              DOI 10.17487/RFC7593, September 2015,
              <https://www.rfc-editor.org/rfc/rfc7593>.

   [RFC8446]  Rescorla, E., "The Transport Layer Security (TLS) Protocol
              Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018,
              <https://www.rfc-editor.org/rfc/rfc8446>.

   [RFC8559]  DeKok, A. and J. Korhonen, "Dynamic Authorization Proxying
              in the Remote Authentication Dial-In User Service (RADIUS)
              Protocol", RFC 8559, DOI 10.17487/RFC8559, April 2019,
              <https://www.rfc-editor.org/rfc/rfc8559>.

   [RFC8952]  Larose, K., Dolson, D., and H. Liu, "Captive Portal
              Architecture", RFC 8952, DOI 10.17487/RFC8952, November
              2020, <https://www.rfc-editor.org/rfc/rfc8952>.

   [RFC9364]  Hoffman, P., "DNS Security Extensions (DNSSEC)", BCP 237,
              RFC 9364, DOI 10.17487/RFC9364, February 2023,
              <https://www.rfc-editor.org/rfc/rfc9364>.

   [TS23003]  3GPP, "3GPP 23.003: Numbering, addressing and
              identification v18.1.0", 28 March 2023,
              <https://www.3gpp.org/ftp/Specs/
              archive/23_series/23.003/23003-i10.zip>.

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   [WBAEIPP]  Wireless Broadband Alliance, "WBA Enhanced IMSI Privacy
              Protection", August 2022,
              <https://wballiancec.wpenginepowered.com/wp-
              content/uploads/2021/02/IMSI_Privacy_Protection_for_Wi-
              Fi_Technical_Specification_v1.1.0_Revision_FINAL.pdf>.

   [WBAPKICP] Wireless Broadband Alliance, "WBA PKI Certificate Policy
              v4.0.0", April 2024,
              <https://wballiance.com/openroaming/pki-repository/>.

   [WBAPKICPS]
              Wireless Broadband Alliance, "WBA PKI Certificate Practise
              Statement v1.0.0", September 2025,
              <https://wballiance.com/openroaming/pki-repository/>.

   [WBAVSA]   Wireless Broadband Alliance, "Vendor Specific Attributes",
              n.d., <https://github.com/wireless-broadband-alliance/
              RADIUS-VSA>.

Appendix A.  Example OpenRoaming Signalling Flow

   An example signalling flow for OpenRoaming is illustrated in
   Figure 12.

   1.   In step 1, the WLAN is configured with Passpoint information and
        includes configured RCOIs in its beacon.

   2.   The beacon can only contain 3 RCOIs and so if none of the RCOIs
        match a profile provisioned in the device, the device queries
        for the list of RCOIs supported.

   3.   If the list includes an RCOI that matches a configured profile
        in the device, then device sends an EAPOL Start message to the
        authenticator.

   4.   The authenticator in the AP/WLC requests the EAP-Identity of the
        device.

   5.   The device responds with its EAP-Identity, which is a user@realm
        Network Access Identifier (NAI)

   6.   The NAS in the WLC/AP embeds the NAI in the user-name attribute
        in a RADIUS Access-Request packet and forwards to the configured
        RadSec client.

   7.   The RadSec client recovers the realm from the NAI/user-name
        attribute and performs a DNS-based dynamic peer discovery.

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   8.   The RadSec client established an mTLS authenticated TLS session
        with the discovered peer using certificates issued by the WBA
        PKI.

   9.   Once TLS is established, the RadSec client forwards the Access-
        Request to the RadSec server.

   10.  If the EAP Server is not co-located with the RadSec server, the
        RadSec server proxies the Access-Request to the EAP-Server.

   11.  The EAP-Server continues the EAP dialogue with the EAP
        Supplicant in the end-user device using a Passpoint defined EAP
        method.

   12.  Following successful authentication, the EAP-Server responds
        with a RADIUS Access-Accept packet containing the EAP-SUCCESS
        message and the keying material generated through the EAP method
        to secure the Wi-Fi session.

   13.  The Access-Accept packet is forwarded back to the RadSec client.

   14.  The RadSec client forwards the Access-Accept packet to the NAS
        in the AP/WLC.

   15.  The AP/WLC recovers the keying material from the Access-Accept
        packet and forwards the EAP-SUCCESS message to the device.

   16.  The keying material is used to secure the Wi-Fi interface
        between the end-user device and AP/WLC.

   17.  The AP/WLC generates a RADIUS Accounting-Request packet with
        Acct-Status-Type Start which is forwarded to the RadSec client.

   18.  The RadSec client forwards the Accounting-Request packet over
        the TLS tunnel to the RadSec server.

   19.  The RadSec server can forward the Accounting-Request packet to
        the EAP-Server.

      20-22.  After the Wi-Fi session terminates, an Accounting-Request
      message with Acct-Status-Type Stop is proxied towards the RadSec
      Server.

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   +------+    +------+    +------+    +------+    +------+    +------+
   |      |    |Wi-Fi |    |RadSec|    |      |    |RadSec|    |  EAP |
   |Device|    |AP/WLC|    |Client|    | DNS  |    |Server|    |Server|
   +------+    +------+    +------+    +------+    +------+    +------+
      | 1) Beacon |           |           |           |           |
      |<----------|           |           |           |           |
      | 2) ANQP   |           |           |           |           |
      | Query     |           |           |           |           |
      |<--------->|           |           |           |           |
      | 3) EAPOL  |           |           |           |           |
      | Start     |           |           |           |           |
      |---------->|           |           |           |           |
      | 4) EAP-ID |           |           |           |           |
      | Request   |           |           |           |           |
      |<----------|           |           |           |           |
      | 5) EAP-ID | 6) RADIUS |           |           |           |
      | Response  | Access-   | 7) DNS    |           |           |
      |---------->| Request   | Query     |           |           |
      |           |---------->| NAPTR,SRV,|           |           |
      |           |           | A/AAAA    |           |           |
      |           |           | Records   |           |           |
      |           |           |<--------->|           |           |
      |           |           | 8) mTLS   |           |           |
      |           |           |<--------------------->|           |
      |           |           | 9) RadSec |           |           |
      |           |           | Access-Request        |           |
      |           |           |---------------------->|           |
      |           |           |           |           | 10) RADIUS|
      |           |           |           |           | Access-   |
      |           |           |           |           | Request   |
      |           |           |           |           |---------->|
      |           |         11) EAP Dialogue          |           |
      |<--------------------------------------------------------->|
      |           |           |           |           | 12) RADIUS|
      |           |           |           |           | Access-   |
      |           | 14) RADIUS|           |           | Accept    |
      |           | Access-   |           |           | (EAP-     |
      |           | Accept    | 13) RadSec Access-    | SUCCESS)  |
      |           | (EAP-     | Accept (EAP-SUCCESS)  |<----------|
      | 15) EAP-  | SUCCESS)  |<----------------------|           |
      | SUCCESS   |<----------|           |           |           |
      |<----------|           |           |           |           |
    +---------------+         |           |           |           |
    | 16) Secured   |         |           |           |           |
    |  OpenRoaming  17) RADIUS|           |           |           |
    |    Service    Accounting|           |           |           |
    |               Request   |           |           | 19) RADIUS|
    |               (Start)   | 18) RadSec Accounting | Accounting|

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    |               |-------->| -Request (Start)      | Request   |
    |               |         |---------------------->| (Start)   |
    |               |         |           |           |---------->|
    +---------------+         |           |           |           |
      |           | 20) RADIUS|           |           |           |
      |           | Accounting|           |           |           |
      |           | Request   |           |           | 22) RADIUS|
      |           | (Stop)    | 21) RadSec Accounting | Accounting|
      |           |---------->| -Request (Stop)       | Request   |
      |           |           |---------------------->| (Stop)    |
      |           |           |           |           |---------->|
   +------+    +------+    +------+    +------+    +------+    +------+
   |Device|    |Wi-Fi |    |RadSec|    | DNS  |    |RadSec|    |  EAP |
   |      |    |AP/WLC|    |Client|    |      |    |Server|    |Server|
   +------+    +------+    +------+    +------+    +------+    +------+

               Figure 12: Example OpenRoaming Signalling Flow

Appendix B.  Example OpenRoaming RCOI Usage

   This Annex illustrates the use of OpenRoaming RCOIs to enforce
   different policies in the OpenRoaming federation, ensuring that when
   there is a policy mismatch between the end-user device and access
   network, that the end-user device will avoid triggering an
   authentication exchange that would subsequently have to be rejected
   because of policy enforcement decisions.

B.1.  OpenRoaming RCOI Based Policy for Supporting QoS Tiers

   Figure 13 illustrates the use of OpenRoaming RCOIs for supporting the
   standard (bronze) and silver QoS tiers across the federation.  The
   figure shows two different devices:

   *  Device 1 has been provisioned by its IDP to require the basic
      bronze QoS policy.

   *  Device 2 has been provisioned by its IDP to require the silver
      tier of QoS handling.

   The figure also shows illustrates the RCOI configuration of two ANP
   Access Networks:

   *  ANP#1 is configured to support the silver tier of QoS handling
      corresponding to the silver RCOI.  Because the network
      requirements associated with the silver tier are a superset of the
      bronze QoS tier, the ANP also configures the bronze RCOI on its
      Wi-Fi access network.

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   *  ANP#2 is only configured to support the standard (bronze) QoS tier
      and as such only configures the RCOI corresponding to the bronze
      QoS tier on its Wi-Fi access network.

   The figure shows how normal Passpoint RCOI matching rules can be used
   to ensure that devices only trigger authentication with ANP access
   networks which support the required QoS tier according to the
   device's policy.

   +----------------------+      +----------------------+
   |OpenRoaming Device #1 |      |OpenRoaming Device #2 |
   | Bronze Service Level |      | Silver Service Level |
   | +------------------+ |      | +------------------+ |
   | |Passpoint Profile | |      | |Passpoint Profile | |
   | |   Bronze RCOI    | |      | |   Silver RCOI    | |
   | +------------------+ |      | +------------------+ |
   |     /|\        /|\   |      |           /|\        |
   +------|----------|----+      +------------|---------+
          |          |                        | RCOI
          |          |                        | Match
          |     +-----------------------------+
     RCOI |     |    |
    Match |     |    |
          |     |    +------------------------+
          |     |                             | RCOI
          |     |                             | Match
         \|/   \|/                           \|/
   +----------------------+       +----------------------+
   |  OpenRoaming ANP#1   |       |  OpenRoaming ANP#2   |
   |      Silver QoS      |       |      Bronze QoS      |
   |   +--------------+   |       |   +--------------+   |
   |   |     WLAN     |   |       |   |     WLAN     |   |
   |   | Bronze RCOI  |   |       |   | Bronze RCOI  |   |
   |   | Silver RCOI  |   |       |   |              |   |
   |   +--------------+   |       |   +--------------+   |
   +----------------------+       +----------------------+

        Figure 13: Use of OpenRoaming RCOIs to realize QoS policies

B.2.  OpenRoaming RCOI Based Policy for Supporting Identity Type
      Policies

   Figure 14 illustrates the use of OpenRoaming RCOIs for supporting
   different identity type policies across the federation.  The figure
   shows two different devices:

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   *  Device#1 has been provisioned by an IDP corresponding to a service
      provider.  It provisions the device's Passpoint profile with the
      RCOI policy identifying the service provider ID-type policy as
      well as the "any ID-type" RCOI policy.

   *  Device 2 has been provisioned by a IDP corresponding to a
      hospitality provider.  It provisions the device's Passpoint
      profile with the RCOI policy identifying the hospitality ID-type
      policy as well as the "any ID-type" RCOI policy.

   The figure also shows the RCOI configuration of three different ANP
   Access Networks:

   *  ANP#1 only supports access using service provider type-IDs and so
      has configured the service provider ID-type policy RCOI.

   *  ANP#2 supports access from all identity types and so has
      configured the any ID-type policy RCOI.

   *  ANP#3 only supports access using hospitality type IDs and so has
      configured the hospitality ID-type policy RCOI.

   The figure shows how normal Passpoint RCOI matching rules can be used
   to ensure that devices only trigger authentication with ANP access
   networks which support the required identity types according to the
   ANP's policy.

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   +----------------------------+   +-----------------------------+
   |   OpenRoaming Device #1    |   |    OpenRoaming Device #2    |
   |  IDP is Service Provider   |   | IDP is Hospitality Provider |
   |+------------++------------+|   |+------------++------------+ |
   || Passpoint  || Passpoint  ||   || Passpoint  || Passpoint  | |
   ||  Profile   ||  Profile   ||   ||  Profile   ||  Profile   | |
   ||     SP     ||Any ID-Type ||   ||Any ID-Type || Hospitality| |
   ||ID-Type RCOI||    RCOI    ||   ||   RCOI     ||ID-Type RCOI| |
   |+------------++------------+|   |+------------++------------+ |
   |      /|\          /|\      |   |       /|\        /|\        |
   +-------|------------|-------+   +-------------------|---------+
           |            |                    |          |
           | RCOI       | RCOI               | RCOI     | RCOI
           | Match      | Match              | Match    | Match
           |            |                    |          |
           |            +-----+        +-----+          |
           |                  |        |                |
          \|/                \|/      \|/              \|/
   +------------------+  +------------------+  +------------------+
   |OpenRoaming ANP#1 |  |OpenRoaming ANP#2 |  |OpenRoaming ANP#3 |
   |  Only accepts    |  |    Accepts all   |  |   Only accepts   |
   | Service Provider |  |     ID-Types     |  |    Hospitality   |
   |     ID-Types     |  |                  |  |     ID-Types     |
   | +--------------+ |  | +--------------+ |  | +--------------+ |
   | |     WLAN     | |  | |     WLAN     | |  | |     WLAN     | |
   | |  SP ID-Type  | |  | | Any ID-Type  | |  | |  Hospitality | |
   | |     RCOI     | |  | |     RCOI     | |  | | ID-Type RCOI | |
   | +--------------+ |  | +--------------+ |  | +--------------+ |
   +------------------+  +------------------+  +------------------+

      Figure 14: Use of OpenRoaming RCOIs to realize ID-Type policies

B.3.  OpenRoaming RCOI Based Policy for Supporting Different Identity
      Proofing Policies

   Figure 15 illustrates the use of OpenRoaming RCOIs for supporting
   different identity proofing policies across the federation.  The
   figure shows two different devices:

   *  Device 1 has been provisioned by an IDP that uses enhanced
      identity proofing controls that meet the enhanced OpenRoaming
      requirements, equivalent to LoA 3 in [ISO29115].  Because the
      enhanced identity proofing requirements are a superset of the
      requirements of the baseline identity proofing policy, the IDP
      also configures the use of the RCOI with baseline identity
      proofing.

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   *  Device 2 has been provisioned by an IDP that uses identity
      proofing with controls that meet the baseline OpenRoaming
      requirements.

   The figure also shows the RCOI configuration of two ANP Access
   Networks:

   *  ANP#1 is operated in a geography where regulations require support
      of enhanced identity proofing.

   *  ANP#2 is operated in a geography where regulations permit support
      of authentications with identities managed using the OpenRoaming
      baseline identity proofing requirements.

   The figure shows how normal Passpoint RCOI matching rules can be used
   to ensure that devices only trigger authentication with ANP access
   networks which support the required identity proofing according to
   the ANP's policy.

   +----------------------------+   +----------------------------+
   |    OpenRoaming Device #1   |   |    OpenRoaming Device #2   |
   |     IDP uses enhanced      |   |     IDP uses baseline      |
   |     identity proofing      |   |     identity proofing      |
   |+------------++------------+|   |       +------------+       |
   || Passpoint  ||  Passpoint ||   |       |  Passpoint |       |
   ||  Profile   ||   Profile  ||   |       |   Profile  |       |
   ||Enhanced LoA||Baseline LoA||   |       |Baseline LoA|       |
   ||    RCOI    ||    RCOI    ||   |       |    RCOI    |       |
   |+------------++------------+|   |       +------------+       |
   |      /|\          /|\      |   |             /|\            |
   +-------|------------|-------+   +--------------|-------------+
           | RCOI       | RCOI                     | RCOI
           | Match      | Match                    | Match
           |            +--------------------+     +-----+
           |                                 |           |
          \|/                               \|/         \|/
      +------------------------+       +------------------------+
      |   OpenRoaming ANP#1    |       |   OpenRoaming ANP#2    |
      | Operates in a country  |       | Operates in a country  |
      |  where the regulator   |       |  where the regulator   |
      |   requires enhanced    |       |   permits baseline     |
      |   identity proofing    |       |   identity proofing    |
      |    +--------------+    |       |    +--------------+    |
      |    |     WLAN     |    |       |    |     WLAN     |    |
      |    | Enhanced LoA |    |       |    | Baseline LoA |    |
      |    |     RCOI     |    |       |    |     RCOI     |    |
      |    +--------------+    |       |    +--------------+    |
      +------------------------+       +------------------------+

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      Figure 15: Use of OpenRoaming RCOIs to realize identity proofing
                                  policies

Appendix C.  OpenRoaming Legal Framework

C.1.  Seamless Experience

   In order for OpenRoaming to avoid the need for end-users to be
   presented with and accept legal terms and conditions covering their
   use of the Wi-Fi hotspot service, there needs to be a legal framework
   in place.

C.2.  OpenRoaming Organization

   The federation is based on a legal framework that comprises a set of
   policies, templated agreements and immutable terms as agreed to by
   the WBA and its membership.  The framework defines a hierarchy of
   roles, responsibilities and relationships that are designed to enable
   the federation to scale to millions of Wi-Fi access networks.

   Figure 16 shows the relationships between WBA, OpenRoaming Brokers,
   who are members of the WBA that have agreed terms with WBA to perform
   the OpenRoaming broker role and the OpenRoaming providers.
   OpenRoaming brokers agree terms with OpenRoaming Providers that can
   act as Access Network Providers (ANPs) and/or Identity Providers
   (IDPs).  OpenRoaming providers do not have to be members of the WBA
   to provide OpenRoaming services.  Finally, OpenRoaming IDPs agree
   terms with OpenRoaming end-users who then benefit from seamless
   authentication onto the Wi-Fi networks deployed by the different
   OpenRoaming ANPs.

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                               +----------+
                               | Wireless |
                               | Broadband|
                               | Alliance |
                               +----------+
                                 /|\  /|\
                                  |    |
                             Agrees terms with
                                  |    |
             +-----------+        |    |        +-----------+
             |OpenRoaming|<-------+    +------->|OpenRoaming|
             |Broker     |                      |Broker     |
             +-----------+                      +-----------+
                /|\  /|\                           /|\  /|\
                 |    |                             |    |
            Agrees terms with                  Agrees terms with
                 |    |                             |    |
           +-----+    +-----+                 +-----+    +-----+
           |                |                 |                |
          \|/              \|/               \|/              \|/
   +-----------+     +-----------+     +-----------+     +-----------+
   |OpenRoaming|     |OpenRoaming|     |OpenRoaming|     |OpenRoaming|
   |Access     |     |Identity   |     |Identity   |     |Access     |
   |Network    |     |Provider   |     |Provider   |     |Network    |
   |Provider   |     |           |     |           |     |Provider   |
   +-----------+     +-----------+     +-----------+     +-----------+
                      /|\  /|\            /|\  /|\
                       |    |              |    |
                  Agrees terms with   Agrees terms with
                       |    |              |    |
         +-------------+    |              |    +------------+
         |                  |              |                 |
        \|/                \|/            \|/               \|/
   +-----------+     +-----------+     +-----------+     +-----------+
   |OpenRoaming|     |OpenRoaming|     |OpenRoaming|     |OpenRoaming|
   |End-User   |     |End-User   |     |End-User   |     |End-User   |
   +-----------+     +-----------+     +-----------+     +-----------+

           Figure 16: Organization of the OpenRoaming Federation

C.3.  OpenRoaming Legal Terms

   In OpenRoaming there is no direct agreement between individual ANPs
   and individual IDPs or between end-users and ANPs.  As a consequence,
   OpenRoaming brokers agree to use certain federation-specific terms in
   their agreements with OpenRoaming providers.

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   This arrangement ensures that all ANPs agree to abide by the
   OpenRoaming privacy policy [ORPRIVACY] and all end-users agree to
   abide by the OpenRoaming end-user Terms and Conditions [ORTERMS].

C.4.  ANP Performance Data

   ANPs MAY voluntarily share performance data with IDPs related to the
   performance of ANP's wireless network used by the IDP's OpenRoaming
   end-users.  IDPs that do not separately agree to terms with ANP
   governing use of performance data MUST solely process collected
   performance data for the purposes of provision of the service,
   including making service authorization decisions and network
   troubleshooting.  These IDPs MUST NOT disclose such performance data
   to any third party except as necessary for direct network
   troubleshooting with the originating ANP.

C.5.  Service Abuse

   If an ANP detects service abuse by an end-user in contravention of
   the end-user Terms and Conditions, the ANP SHOULD record logs
   relevant to the abuse and use the email address embedded in the
   Subject Alternative Name (SAN) attribute in IDP's issued end-entity
   certificate to contact the abuser's IDP, indicating the nature of the
   abuse together with any relevant logs.  The immutable terms of
   OpenRoaming REQUIRE IDPs to make reasonable efforts to address the
   service abuse experienced by the ANP, which may include the
   withdrawal of the OpenRoaming service from the identified abusive
   end-user.

C.6.  OpenRoaming Troubleshooting

   The immutable terms included in the OpenRoaming templated agreements
   require OpenRoaming providers to make reasonable efforts to support
   troubleshooting procedures, including monitoring email addresses
   shared for troubleshooting purposes.

   OpenRoaming defines the following severity levels:

   *  Severity 1: OpenRoaming service is not available,

   *  Severity 2: OpenRoaming service is severely impacted,

   *  Severity 3: OpenRoaming service is partially degraded, and

   *  Severity 4: Informational.

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   Prior to escalating any issue with a third party, the initiating
   provider should conduct an initial assessment, logging any
   troubleshooting steps and recording all logs relevant to the issue.
   The initiating provider should designate a contact for handling
   troubleshooting and share such with the third-party provider contact
   identified via the respective WBA PKI certificate, together with
   details of the issue, including its severity.

C.6.1.  Issue Response

   The third-party shall respond to all escalations raised by initiating
   providers.  The recommended maximum timeframes for the initial email
   response for issue response associated with the OpenRoaming Settled
   Service are as follows:

   *  Severity 1: Email response within 2 days.

   *  Severity 2: Email response within 4 days.

   *  Severity 3: Email response within 8 days.

   *  Severity 4: Email response within 28 days.

   This does not preclude a provider unilaterally agreeing to shorter
   timeframes for responding to initial issues.  The initiating provider
   and the third-party shall use reasonable efforts to try and identify
   any issues and remediate any problems.  Both providers should record
   affected systems and attempted resolutions.

C.6.2.  Issue Escalation

   If the issue cannot be resolved to the acceptance of both providers
   within an acceptable timeframe, the provider may escalate the issue
   to WBA.

   The recommended maximum timeframes before escalations associated with
   OpenRoaming Settled Service are escalated to WBA as follows:

   *  Severity 1: Escalate after 4 working-days of issue non-resolution.

   *  Severity 2: Escalate after 8 working-days of issue non-resolution.

   *  Severity 3: Escalate after 28 working-days of issue non-
      resolution.

   *  Severity 4: Escalation is not applicable.

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   This does not preclude both access network and identity providers
   bilaterally agreeing to shorter timeframes for handling issue
   escalation.

   Escalation includes sharing all logs and correspondence regarding the
   issue and attempts at resolution.

C.7.  Breach of Contract

   Where it can be determined that an End-Entity is in breach of their
   contract terms as defined in the OpenRoaming legal framework, WBA
   reserves the right to cancel the End-Entity's OpenRoaming enrolment
   and revoke any WBA issued certificates.

Changelog

   *  01 - added details of WBA-Custom-SLA for OpenRoaming ANP networks
      that signal using [RFC7268] that they operate on a vehicular
      platform.  Added clarifications regarding use of direct and
      indirect names in certificate validation.

   *  02 - added details of OpenRoaming protection of end-user privacy,
      including WRIX recommendations on use of correlation identifiers
      in RADIUS Access-Accept packet that may unintentionally weaken
      end-user privacy.

   *  03 - updated DNSsec reference.  Added section on interworking with
      other federations.

   *  04 - updated PKI Policy OID to reflect new certificate chain.
      Added IDP availability requirements.  Added session-timeout
      requirements.  Added new onboarding capabilities for short lived
      credentials.  Added text concerning OpenRoaming Privacy Policy and
      restrictions on location usage.

   *  05 - added new section on use of Reply-Message, added new text on
      troubleshooting, clarified RADIUS accounting handling, clarified
      CUI usage in Access-Accept, clarified use of EAP types.

   *  06 - corrected ePDG FQDN.  Added missing enhanced Reply-Message
      for cause-code = 45.  Added new text regarding recommended best
      practice for firewall deployment on public Internet facing
      interfaces should be followed for ANP RADSEC connections and for
      protecting end-users.

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   *  07 - added details of service abuse handling.  Added further
      details of RADIUS attributes.  Added rationale for busy hour
      sustained throughput values.  Introduced requirements on minimum
      speeds for OpenRoaming bronze and silver tiers.  Corrected WBAID
      ABNF by adding in permitted special characters.

   *  08 - added clarification on the use of "aaa+auth" to identify a
      RadSec server that supports both RADIUS authentication and
      accounting.  Added requirements for reverse CoA and associated
      RadSec connection management.  Added support for enhanced RADIUS
      connect-info for connection instrumentation and authorization.

Acknowledgements

   The authors would like to thank all the members of the WBA's
   OpenRoaming Workgroup who help define the OpenRoaming specifications.

Authors' Addresses

   Bruno Tomas
   Wireless Broadband Alliance, Inc.
   5000 Executive Parkway, Suite 302
   San Ramon,  94583
   United States of America
   Email: bruno@wballiance.com

   Mark Grayson
   Cisco Systems
   10 New Square Park
   Feltham
   TW14 8HA
   United Kingdom
   Email: mgrayson@cisco.com

   Necati Canpolat
   Intel Corporation
   2111 NE. 25th Ave
   Hillsboro,  97124
   United States of America
   Email: necati.canpolat@intel.com

   Betty A. Cockrell
   Independent
   San Antonio,
   United States of America

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   Email: bcbeti@outlook.com

   Sri Gundavelli
   Cisco Systems
   170 West Tasman Drive
   San Jose,  95134
   United States of America
   Email: sgundave@cisco.com

   Seb Adamski
   IronWiFi
   100 E Pine St, Ste 110
   Orlando,  32801
   United States of America
   Email: seb@ironwifi.com

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