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WBA OpenRoaming Wireless Federation
draft-tomas-openroaming-03

Document Type Active Internet-Draft (individual)
Authors Bruno Tomas , Mark Grayson , Necati Canpolat , Betty A. Cockrell , Sri Gundavelli
Last updated 2024-07-25
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draft-tomas-openroaming-03
Independent Submission                                          B. Tomas
Internet-Draft                         Wireless Broadband Alliance, Inc.
Intended status: Informational                                M. Grayson
Expires: 26 January 2025                                   Cisco Systems
                                                             N. Canpolat
                                                       Intel Corporation
                                                          B. A. Cockrell
                                                            SingleDigits
                                                           S. Gundavelli
                                                           Cisco Systems
                                                            25 July 2024

                  WBA OpenRoaming Wireless Federation
                       draft-tomas-openroaming-03

Abstract

   This document describes the Wireless Broadband Alliance's OpenRoaming
   system.  The OpenRoaming architectures 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 26 January 2025.

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Copyright Notice

   Copyright (c) 2024 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  . . . . . . . . . . . . . . . . . . . . . . . .   3
     1.1.  Requirements Language . . . . . . . . . . . . . . . . . .   4
     1.2.  Terminology . . . . . . . . . . . . . . . . . . . . . . .   4
   2.  Wireless Broadband Alliance . . . . . . . . . . . . . . . . .   6
   3.  OpenRoaming Architecture  . . . . . . . . . . . . . . . . . .   7
   4.  Identifying OpenRoaming Entities  . . . . . . . . . . . . . .  10
   5.  Scaling Secured Signalling  . . . . . . . . . . . . . . . . .  10
   6.  IDP Discovery . . . . . . . . . . . . . . . . . . . . . . . .  11
     6.1.  Dynamic Discovery . . . . . . . . . . . . . . . . . . . .  11
     6.2.  Discovery of EAP-AKA/AKA' Servers . . . . . . . . . . . .  12
     6.3.  Proving a discovered RadSec server is authoritative for a
           realm . . . . . . . . . . . . . . . . . . . . . . . . . .  12
     6.4.  Co-existence with other Federations . . . . . . . . . . .  13
   7.  OpenRoaming Passpoint Profile . . . . . . . . . . . . . . . .  14
     7.1.  OpenRoaming Policy Controls . . . . . . . . . . . . . . .  14
     7.2.  OpenRoaming Closed Access Group Policies  . . . . . . . .  14
       7.2.1.  Level of Assurance Policies . . . . . . . . . . . . .  15
       7.2.2.  Quality of Service Policies . . . . . . . . . . . . .  16
       7.2.3.  Privacy Policies  . . . . . . . . . . . . . . . . . .  18
       7.2.4.  ID-Type Policies  . . . . . . . . . . . . . . . . . .  19
     7.3.  Prioritizing Policies . . . . . . . . . . . . . . . . . .  21
   8.  OpenRoaming RADIUS Profile  . . . . . . . . . . . . . . . . .  21
     8.1.  Operator-Name . . . . . . . . . . . . . . . . . . . . . .  21
     8.2.  Chargeable-User-Identity  . . . . . . . . . . . . . . . .  21
     8.3.  Location-Data/Location-Information  . . . . . . . . . . .  22
     8.4.  WBA-Identity-Provider . . . . . . . . . . . . . . . . . .  22
     8.5.  WBA-Offered-Service . . . . . . . . . . . . . . . . . . .  22
     8.6.  WLAN-Venue-Info . . . . . . . . . . . . . . . . . . . . .  22
     8.7.  WBA-Custom-SLA  . . . . . . . . . . . . . . . . . . . . .  23
     8.8.  Additional attributes related to OpenRoaming settled  . .  23
       8.8.1.  WBA-Financial-Clearing-Provider . . . . . . . . . . .  23
       8.8.2.  WBA-Data-Clearing-Provider  . . . . . . . . . . . . .  23
       8.8.3.  WBA-Linear-Volume-Rate  . . . . . . . . . . . . . . .  23
   9.  Security Considerations . . . . . . . . . . . . . . . . . . .  23
     9.1.  Network Selection and Triggering Authentication . . . . .  23

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     9.2.  Dynamic Discovery of RadSec Peers . . . . . . . . . . . .  24
     9.3.  End-User Traffic  . . . . . . . . . . . . . . . . . . . .  24
   10. Future Enhancements . . . . . . . . . . . . . . . . . . . . .  25
   11. IANA Considerations . . . . . . . . . . . . . . . . . . . . .  25
   12. References  . . . . . . . . . . . . . . . . . . . . . . . . .  25
     12.1.  Normative References . . . . . . . . . . . . . . . . . .  25
     12.2.  Informative References . . . . . . . . . . . . . . . . .  25
   Appendix A.  Example OpenRoaming Signalling Flow  . . . . . . . .  28
   Appendix B.  Example OpenRoaming RCOI Usage . . . . . . . . . . .  31
     B.1.  OpenRoaming RCOI based policy for supporting QoS tiers  .  31
     B.2.  OpenRoaming RCOI based policy for supporting identity type
           policies  . . . . . . . . . . . . . . . . . . . . . . . .  33
     B.3.  OpenRoaming RCOI based policy for supporting different
           identity proofing policies  . . . . . . . . . . . . . . .  34
   Appendix C.  OpenRoaming legal framework  . . . . . . . . . . . .  36
     C.1.  Seamless experience . . . . . . . . . . . . . . . . . . .  37
     C.2.  OpenRoaming Organization  . . . . . . . . . . . . . . . .  37
     C.3.  OpenRoaming legal terms . . . . . . . . . . . . . . . . .  38
   Changelog . . . . . . . . . . . . . . . . . . . . . . . . . . . .  39
   Acknowledgements  . . . . . . . . . . . . . . . . . . . . . . . .  39
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  39

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] provide 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.

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   OpenRoaming is designed to deliver end-to-end security between a
   Network Access Server 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].

   Access Network Provider (ANP):

      An entity that has joined the federation and serves OpenRoaming
      end-users by configuring the OpenRoaming RCOI(s) in its Wi-Fi
      equipment.

   Broker:

      An entity that 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 to ANPs and IDPs.

         2.  Operating an issuing intermediate certificate 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 certificate authority under
             WBA's PKI to enable certificates to be issued to ANPs and
             IDPs.

   Closed Access Group (CAG):

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      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.

   Level of Assurance (LoA):

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

   OpenRoaming-Settled:

      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, to enables Wi-Fi
      devices to discover and authenticate to Wi-Fi hotspots that
      provide Internet access [PASSPOINT].

   PLMN Id:

      Is a unique identifier for a mobile network operator.  The
      identifier consists of a MCC (Mobile Country Code) and a MNC
      (Mobile Network Code).  [PASSPOINT] defines how the PLMN Id can be
      sent in ANQP messages.

   Roaming Consortium Identifier (RCOI):

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      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.

   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.

   Wireless Roaming Intermediary eXchange:

      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

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   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, the decreasing costs for cellular data
   means 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.

3.  OpenRoaming Architecture

   Figure 2 contrasts a conventional carrier Wi-Fi roaming system with
   OpenRoaming.  As illustrated, conventional Wi-Fi roaming is typically
   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 in 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 certificate authority.

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

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

   4.  Passpoint authentication that can use any of the Passpoint
       defined EAP methods.

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

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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 Carrier Wi-Fi and OpenRoaming Architectures

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4.  Identifying OpenRoaming Entities

   All OpenRoaming providers 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".

   upper-case-char = %x41-5a
   member-id       = 1*upper-case-char
   wbaid           = member-id [ %x3a 2*2upper-case-char]

            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., "OPENROAMINGPROVIDER.WBAMEMBER:US".  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.

5.  Scaling Secured Signalling

   As described in Appendix C, the OpenRoaming legal framework does not
   assume any direct relationship between ANP and IDP.  In order to
   scale the secured signalling between providers, the federation makes
   use of a Public Key Infrastructure 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 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 1.3.6.1.4.1.14122.1.1.6.

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

   +---------+---------------------------+----------------------------+
   |         |                           |                            |
   | 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 OID|
   |         | Authority                 |                            |
   +---------+---------------------------+----------------------------+
   | 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 ANPs
   network and an RadSec Server in the OpenRoaming IDPs network,
   although a provider can decide to outsource the operation of the
   RadSec endpoint to a third party provider.

6.  IDP Discovery

6.1.  Dynamic Discovery

   OpenRoaming defines the use of dynamic discover [RFC7585] by which an
   ANP discovers the IP address of the IDP's RadSec server.

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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.

   GSMA IR.67 does allow systems to be discoverable from the public
   Internet, specifically calling out the use of the pub.3gppnetwork.org
   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.  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.mnc<MNC>.mcc<MCC>.pub.3gppnetwork.org 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 have not enabled DNSSEC on their 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.

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   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.

   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 Certificate
   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 Certificate 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.

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7.  OpenRoaming Passpoint Profile

7.1.  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 on the user experience.

   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.

7.2.  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.

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   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 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       |Reserved - set to 0|
   +----+---------+----+-------------------+-------------------+

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

7.2.1.  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].

   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".

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   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.

7.2.2.  Quality of Service Policies

   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 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.

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   2.  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:

   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 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.

   3.  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.

   4.  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 normal OpenRoaming service
   level requirements.  This is because such installations may
   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-

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

7.2.3.  Privacy Policies

   The baseline privacy policy of OpenRoaming 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
   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.  When using typical public Wi-Fi session
   durations, it is estimated that, with this 2 hour restriction, the
   ANP will be able to correlate an Access-Request/Access-Accept
   exchange that immediately follows an Accounting-Request stop message
   in over 50% of the sessions.

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   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.

   The PID field can be used to support scenarios where the 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 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 "0" and 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

7.2.4.  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.

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   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.

   +------------------------------------------------------------+
   |       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        |
   +------------------------------------------------------------+
   |  1   |  0   |  1   |  1   | A retail identity              |
   +------------------------------------------------------------+
   |        other values       | Reserved                       |
   +------------------------------------------------------------+

                  Figure 9: OpenRoaming CAG ID-Type Field

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7.3.  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 RCOI
   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.

8.  OpenRoaming RADIUS Profile

   The OpenRoaming RADIUS profile is based on the WBA WRIX Specification
   which in turn are derived from [RFC3580] and [RFC3579].

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

8.1.  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.

8.2.  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.

   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 is invariant over subsequent end-user authentication
   exchanges between the IDP and the ANP.

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8.3.  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 RADIUS Access-Request packet where the location profile is
   the civic location profile that includes the country code where the
   ANP is located in all Access-Request packets [RFC5580].

   When the OpenRoaming ANP supports the OpenRoaming-Settled RCOI ("BA-
   A2-D0"), the Location-Data attribute (#128) MUST be included 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 and this
   information MAY be used by IDPs, e.g., in their authorization
   decisions.

8.4.  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.

8.5.  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].

8.6.  WLAN-Venue-Info

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

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8.7.  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 MAY use
   the WBA-Custom-SLA vendor specific attribute [WBAVSA] to indicate one
   or more (availability, per-user sustained bandwidth) tuples to the
   IDP.

8.8.  Additional attributes related to OpenRoaming settled

   OpenRoaming settled defines the use of additional RADIUS attributes.

8.8.1.  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].

8.8.2.  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].

8.8.3.  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.  Security Considerations

9.1.  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

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   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
   been issued with a certificate using 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.

9.2.  Dynamic Discovery of RadSec Peers

   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 permits the configuration of supported realm(s) in
   the SubjectAltName of the certificate(s) issued to the IDP.

   An ANP can 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.

9.3.  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.

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10.  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 that are reflected in
   the Closed Access Group policies described in Section 7.2 and the
   RADIUS profile described in Section 8.  WBA encourages those parties
   interested in adapting OpenRoaming to address new requirements to
   join the Alliance and help drive the definition of OpenRoaming
   forward.

11.  IANA Considerations

   This document has no IANA actions.

12.  References

12.1.  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>.

12.2.  Informative References

   [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>.

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

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

   [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>.

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   [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>.

   [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>.

   [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>.

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   [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>.

   [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>.

   [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>.

   [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>.

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   [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>.

   [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>.

   [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>.

   [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 10.

   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)

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   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.

   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 device using a Passpoint defined EAP method.

   12.  Following successful authentication, the EAP-Server responds
        with an 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 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 10: 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 device and access network,
   that the 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 11 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 11: Use of OpenRoaming RCOIs to realize QoS policies

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B.2.  OpenRoaming RCOI based policy for supporting identity type
      policies

   Figure 12 illustrates the use of OpenRoaming RCOIs for supporting
   different identity type policies across the federation.  The figure
   shows two different devices:

   *  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 12: Use of OpenRoaming RCOIs to realize ID-Type policies

B.3.  OpenRoaming RCOI based policy for supporting different identity
      proofing policies

   Figure 13 illustrates the use of OpenRoaming RCOIs for supporting
   different identity proofing policies across the federation.  The
   figure shows two different devices:

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   *  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.

   *  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.

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   +----------------------------+   +-----------------------------+
   |    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     |    |
      |    +--------------+    |       |    +--------------+    |
      +------------------------+       +------------------------+

      Figure 13: Use of OpenRoaming RCOIs to realize identity proofing
                                  policies

Appendix C.  OpenRoaming legal framework

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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 14 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 14: 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].

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.

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

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   Email: necati.canpolat@intel.com

   Betty A. Cockrell
   SingleDigits
   San Antonio,
   United States of America
   Email: bcockrell@singledigits.com

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

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