Connectivity Provisioning Negotiation Protocol (CPNP)
draft-boucadair-connectivity-provisioning-protocol-10
Network Working Group M. Boucadair
Internet-Draft C. Jacquenet
Intended status: Experimental France Telecom
Expires: March 19, 2016 D. Zhang
Huawei Technologies
P. Georgatsos
CERTH
September 16, 2015
Connectivity Provisioning Negotiation Protocol (CPNP)
draft-boucadair-connectivity-provisioning-protocol-10
Abstract
This document specifies the Connectivity Provisioning Negotiation
Protocol (CPNP) which is used to facilitate the dynamic negotiation
of service parameters.
CPNP is a generic protocol that can be used for various negotiation
purposes that include (but are not necessarily limited to)
connectivity provisioning services, storage facilities, Content
Delivery Networks (CDN) footprint, etc. CPNP can be extended with
new Information Elements.
Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119].
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
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This Internet-Draft will expire on March 19, 2016.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 5
3. CPNP Functional Elements . . . . . . . . . . . . . . . . . . 6
4. Order Processing Models . . . . . . . . . . . . . . . . . . . 7
5. Sample Use Cases . . . . . . . . . . . . . . . . . . . . . . 8
6. CPNP Deployment Models . . . . . . . . . . . . . . . . . . . 10
7. CPNP Negotiation Model . . . . . . . . . . . . . . . . . . . 11
8. Protocol Overview . . . . . . . . . . . . . . . . . . . . . . 13
8.1. Client/Server Communication . . . . . . . . . . . . . . . 13
8.2. Server Discovery . . . . . . . . . . . . . . . . . . . . 14
8.3. Policy Configuration on the CPNP Server . . . . . . . . . 14
8.4. CPNP Session . . . . . . . . . . . . . . . . . . . . . . 16
8.5. Extended CPNP Session . . . . . . . . . . . . . . . . . . 16
8.6. CPNP Transaction . . . . . . . . . . . . . . . . . . . . 16
8.7. CPNP Timers . . . . . . . . . . . . . . . . . . . . . . . 17
8.8. CPNP Operations . . . . . . . . . . . . . . . . . . . . . 17
8.9. Connectivity Provisioning Documents . . . . . . . . . . . 19
8.10. Child Provisioning Quotation Orders . . . . . . . . . . . 20
8.11. Negotiations with Multiple CPNP Servers . . . . . . . . . 21
8.12. State Management . . . . . . . . . . . . . . . . . . . . 21
8.12.1. On the Client Side . . . . . . . . . . . . . . . . . 22
8.12.2. On the Server Side . . . . . . . . . . . . . . . . . 24
9. CPNP Objects . . . . . . . . . . . . . . . . . . . . . . . . 27
9.1. Attributes . . . . . . . . . . . . . . . . . . . . . . . 27
9.1.1. CUSTOMER_AGREEMENT_IDENTIFIER . . . . . . . . . . . . 27
9.1.2. PROVIDER_AGREEMENT_IDENTIFIER . . . . . . . . . . . . 27
9.1.3. TRANSACTION_ID . . . . . . . . . . . . . . . . . . . 28
9.1.4. SEQUENCE_NUMBER . . . . . . . . . . . . . . . . . . . 28
9.1.5. NONCE . . . . . . . . . . . . . . . . . . . . . . . . 28
9.1.6. EXPECTED_RESPONSE_TIME . . . . . . . . . . . . . . . 28
9.1.7. EXPECTED_OFFER_TIME . . . . . . . . . . . . . . . . . 28
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9.1.8. VALIDITY_OFFER_TIME . . . . . . . . . . . . . . . . . 29
9.1.9. CONNECTIVITY_PROVISIONING_DOCUMENT . . . . . . . . . 29
9.1.10. Information Elements . . . . . . . . . . . . . . . . 29
9.2. Operation Messages . . . . . . . . . . . . . . . . . . . 31
9.2.1. QUOTATION . . . . . . . . . . . . . . . . . . . . . . 31
9.2.2. PROCESSING . . . . . . . . . . . . . . . . . . . . . 31
9.2.3. OFFER . . . . . . . . . . . . . . . . . . . . . . . . 33
9.2.4. ACCEPT . . . . . . . . . . . . . . . . . . . . . . . 33
9.2.5. ACK . . . . . . . . . . . . . . . . . . . . . . . . . 33
9.2.6. DECLINE . . . . . . . . . . . . . . . . . . . . . . . 34
9.2.7. CANCEL . . . . . . . . . . . . . . . . . . . . . . . 35
9.2.8. WITHDRAW . . . . . . . . . . . . . . . . . . . . . . 35
9.2.9. UPDATE . . . . . . . . . . . . . . . . . . . . . . . 36
9.2.10. FAIL . . . . . . . . . . . . . . . . . . . . . . . . 37
10. Message Validation . . . . . . . . . . . . . . . . . . . . . 38
10.1. On the Client Side . . . . . . . . . . . . . . . . . . . 38
10.2. On the Server Side . . . . . . . . . . . . . . . . . . . 39
11. Theory of Operation . . . . . . . . . . . . . . . . . . . . . 40
11.1. Client Behavior . . . . . . . . . . . . . . . . . . . . 40
11.1.1. Order Negotiation Cycle . . . . . . . . . . . . . . 40
11.1.2. Order Withdrawal Cycle . . . . . . . . . . . . . . . 42
11.1.3. Order Update Cycle . . . . . . . . . . . . . . . . . 42
11.2. Server Behavior . . . . . . . . . . . . . . . . . . . . 42
11.2.1. Order Processing . . . . . . . . . . . . . . . . . . 42
11.2.2. Order Withdrawal . . . . . . . . . . . . . . . . . . 44
11.2.3. Order Update . . . . . . . . . . . . . . . . . . . . 44
11.3. Sequence Numbers . . . . . . . . . . . . . . . . . . . . 44
11.4. Message Re-Transmission . . . . . . . . . . . . . . . . 45
12. Operational Guidelines . . . . . . . . . . . . . . . . . . . 45
12.1. Logging on the CPNP Server . . . . . . . . . . . . . . . 45
12.2. Business Guidelines & Objectives . . . . . . . . . . . . 45
13. Security Considerations . . . . . . . . . . . . . . . . . . . 46
14. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 47
15. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 48
16. References . . . . . . . . . . . . . . . . . . . . . . . . . 48
16.1. Normative References . . . . . . . . . . . . . . . . . . 48
16.2. Informative References . . . . . . . . . . . . . . . . . 48
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 50
1. Introduction
This document defines the Connectivity Provisioning Negotiation
Protocol (CPNP) that is meant to dynamically exchange and negotiate
connectivity provisioning parameters, and other service-specific
parameters, between a Customer and a Provider. CPNP is a tool that
introduces automation in the service negotiation and activation
procedures, thus fostering the overall service provisioning process.
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CPNP can be seen as a component of the dynamic negotiation meta-
domain described in Section 3.4 of [RFC7149].
CPNP is a generic protocol that can be used for other negotiation
purposes than connectivity provisioning. For example, CPNP can be
used to request extra storage resources, to extend the footprint of a
CDN (Content Delivery Networks), to enable additional features from a
cloud Provider, etc. CPNP can be extended with new Information
Elements (IEs).
[RFC7297] describes a Connectivity Provisioning Profile (CPP)
template to capture connectivity requirements to be met by a
transport infrastructure for the delivery of various services such as
Voice over IP (VoIP), IPTV, and Virtual Private Network (VPN)
services [RFC4026]. The CPP document defines the set of IP transfer
parameters that reflect the guarantees that can be provided by the
underlying transport network together with reachability scope and
capacity needs. CPNP uses the CPP template to encode connectivity
provisioning clauses.
As a reminder, several proposals have been made in the past by the
(research) community (e.g., COPS-SLS, Service Negotiation Protocol
(SrNP), Dynamic Service Negotiation Protocol (DSNP), Resource
Negotiation and Pricing Protocol (RNAP), Service Negotiation and
Acquisition Protocol (SNAP), etc.). It is out of the scope of this
document to elaborate on the differences between CPNP and the
aforementioned proposals.
This document is organized as follows:
o Section 3 defines the functional elements involved in CPNP
exchanges.
o Section 4 introduces several order processing models and precises
those that are targeted by CPNP.
o Section 5 enumerates a non-exhaustive list of use cases that could
benefit from CPNP.
o Section 5 discusses CPNP deployment models.
o Section 7 presents the CPNP negotiation model.
o Section 8 provides an overview of the protocol.
o Section 9 specifies the CPNP objects.
o Section 10 describes the CPNP message validation procedure.
o Section 11 specifies the behavior of the involved CPNP functional
elements.
o Section 12 discusses relevant operational guidelines.
o Section 13 discusses protocol security aspects.
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2. Terminology
This document makes use of the following terms:
o Customer:
Is a business role which denotes an entity that is involved in the
definition and the possible negotiation of a contract, including a
Connectivity Provisioning Agreement, with a Provider. A
connectivity provisioning contract is captured in a dedicated CPP
template-based document, which specifies (among other
information): the sites to be connected, border nodes, outsourced
operations (e.g., routing, force via points).
The right to invoke the subscribed service may be delegated by the
Customer to third-party End Users, or brokering services.
A Customer can be a Service Provider, an application owner, an
enterprise, a user, etc.
o Network Provider (or Provider):
Owns and administers one or many transport domain(s) (typically
Autonomous System (AS)) composed of IP switching and transmission
resources (e.g., routing, switching, forwarding, etc.). Network
Providers are responsible for ensuring connectivity services
(e.g., offering global or restricted reachability at specific
rates). Offered connectivity services may not necessarily be
restricted to IP.
The policies to be enforced by the connectivity service delivery
components can be derived from the technology-specific clauses
that might be included in contracts agreed with the Customers. If
no such clauses are included in the agreement, the mapping between
the connectivity requirements and the underlying technology-
specific policies to be enforced is deployment-specific.
o Quotation Order:
Denotes a request made by the Customer to the Provider that
includes a set of requirements. The Customer may express its
service-specific requirements by assigning (fixed or loosely
defined) values to the information items included in the commonly
understood template (e.g., CPP template) describing the offered
service. These requirements constitute the parameters to be
mutually agreed upon.
o Offer:
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Refers to a response made by the Provider to a Customer 's
quotation order as to the extent at which the Provider may satisfy
the order at the time of its receipt. Offers reflect the
capability of the Provider in accommodating received Customer
orders beyond monolithic 'yes/no' answers.
An offer may fully or partially meet the requirements of the
corresponding order. In the latter case, it may include
alternative suggestions which the Customer may take into account
by issuing a new order.
o Agreement:
Refers to an order placed by the Customer and accepted by the
Provider. It signals the successful conclusion of a negotiation
cycle.
3. CPNP Functional Elements
The following functional elements are defined:
o CPNP client (or client):
Denotes a software instance that sends CPNP requests and receives
CPNP responses. The current operations that can be performed by a
CPNP client are listed below:
1. Create a quotation order (Section 11.1.1).
2. Cancel an ongoing quotation order under negotiation
(Section 11.1.1).
3. Accept an offer made by a server (Section 11.1.1).
4. Withdraw an agreement (Section 11.1.2).
5. Update an agreement (Section 11.1.3).
o CPNP server (or server):
Denotes a software instance that receives CPNP requests and sends
back CPNP responses accordingly. The CPNP server is responsible
for the following operations:
1. Process a quotation order (Section 11.2.1).
2. Make an offer (Section 11.2.1).
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3. Cancel an ongoing quotation order (Section 11.2.2).
4. Process an order withdrawal (Section 11.2.3).
4. Order Processing Models
For preparing their service orders, the Customers may need to be
aware of the offered services. The Providers therefore should first
proceed with the announcement of the services that they can provide.
The service announcement process may take place at designated global
or Provider-specific service markets, or through explicit
interactions with the Providers. The details of this process are
outside the scope of a negotiation protocol.
With or without such service announcement mechanisms in place, the
following order processing models can be distinguished:
The following order processing models can be distinguished:
1. Frozen model:
The Customer cannot actually negotiate the parameters of the
service(s) offered by a Provider. After consulting the
Provider's service portfolio, the Customer selects the service
offer he/she wants to subscribe and places an order to the
Provider. Order handling is quite simple on the Provider side
because the service is not customized as per Customer's
requirements, but rather pre-designed to target a group of
customers having similar requirements (i.e., these customers
share the same Customer Provisioning Profile).
2. Negotiation-based model:
Unlike the frozen model, the Customer documents his/her
requirements in a request for a quotation, which is then sent to
one or several Providers. Solicited Providers check whether they
can address these requirements or not, and get back to the
Customer accordingly, possibly with an offer that may not exactly
match customer's requirements (e.g., a 100 Mbps connection cannot
be provisioned given the amount of available resources, but an 80
Mbps connection can be provided). A negotiation between the
Customer and the Provider(s) then follows to the end of reaching
an agreement.
Both frozen and negotiation-based models require the existence of
appropriate service templates like a CPP template and their
instantiation for expressing specific offerings from Providers and
service requirements from Customers, respectively. CPNP can be used
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in either model for automating the required Customer-Provider
interactions. Since the frozen model can be seen as a special case
of the negotiation-based model, not only 'yes/no' answers but also
counter offers may be issued by the Provider in response to Customer
orders, this document focuses on the negotiation-based model.
Order processing management on the Network Provider's side is usually
connected with the following functional blocks:
o Network Provisioning (including Order Activation, Network
Planning, etc.)
o Authentication, Authorization and Accounting (AAA)
o Network and service management (performance verification,
complaint analysis, etc.)
o Sales-related functional blocks (e.g., billing, invoice
validation, etc.)
o Network Impact Analysis
CPNP does not assume any specific knowledge about these functional
blocks, drawing an explicit line between protocol operation and the
logic for handling connectivity provisioning requests. Evidently
order handling logic is subject to the information manipulated by
these blocks. For example, the resources that can be allocated to
accommodate Customer's requirements may depend on network
availability estimates as calculated by the planning functions and
related policies as well as on the number of orders to be processed
simultaneously over a given period of time.
This document does not elaborate on how Customers are identified and
subsequently managed by the Provider's Information System.
5. Sample Use Cases
A non-exhaustive list of CPNP use cases is provided below:
1. [RFC4176] introduces the L3VPN Service Order Management
functional block which is responsible for managing the requests
initiated by the Customers and tracks the status of the
completion of the related operations. CPNP can be used between
the Customer and the Provider to negotiate L3VPN service
parameters.
A CPNP server could therefore be part of the L3VPN Service Order
Management functional block discussed in [RFC4176].
2. CPNP can be used between two adjacent domains to deliver IP
interconnection services (e.g., enable, update, disconnect). For
example, two Autonomous Systems (ASes) can be connected via
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several interconnection points. CPNP can be used between these
ASes to upgrade existing links, request additional resources,
provision a new interconnection point, etc.
See for example the framework documented in [ETICS].
3. An integrated Provider can use CPNP to rationalize connectivity
provisioning needs related to its service portfolio. A CPNP
server function is used by network operations teams. A CPNP
interface to invoke CPNP negotiation cycles is exposed to service
management teams.
4. Service Providers can use CPNP to initiate connectivity
provisioning requests towards a number of Network Providers so
that to optimize the cost of delivering their services. Although
multiple CPNP ordering cycles can be initiated by a Service
Provider towards multiple Network Providers, a subset of these
orders may actually be put into effect.
For example, a cloud Service Provider can use CPNP to request
more resources from Network Providers.
5. CPNP can be used in Machine-to-Machine (M2M) environments to
dynamically subscribe to M2M services (e.g., access to data
retrieved by a set of sensors, extend sensor coverage, etc.).
Also, Internet of Things (IoT, [RFC6574]) domains may rely on
CPNP to enable dynamic provisioning of data produced by involved
objects, according to their specific policies, to various
external stakeholders such as data analytics and business
intelligence companies. Direct CPNP-based interactions between
IoT domains and interested parties enable open access to diverse
sets of data across the Internet, e.g., from multiple types of
sensors, user groups and/or geographical areas.
6. A Provider offering cloud services can expose a CPNP interface to
allow Customers to dynamically negotiate related service features
such as additional storage, processing and networking resources,
enhanced security filters, etc.
7. In the inter-cloud context (also called cloud of clouds or cloud
federation), CPNP can be used to reserve external computing and
networking resources in other cloud environments.
8. CDN Providers can use CPNP to extend their footprint by
interconnecting their CDN infrastructure [RFC6770] (see
Figure 1).
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,--,--,--. ,--,--,--.
,-' `-. ,-' `-.
(CDN Provider 'A')=====(CDN Provider 'B')
`-. (CDN-A) ,-' `-. (CDN-B) ,-'
`--'--'--' `--'--'--'
Figure 1: CDN Interconnection
9. LISP ([RFC6830]) Mapping Service Providers can use CPNP to enrich
their mapping database by interconnecting their mapping system
(see Figure 2). This interconnection allows to relax the
constraints on PxTR in favour of native LISP forwarding. Also,
it allows to prevent fragmented LISP mapping database.
,--,--,--. ,--,--,--.
,-' `-. ,-' `-.
(Mapping System 'A')===(Mapping System 'B')
`-. ,-' `-. ,-'
`--'--'--' `--'--'--'
Figure 2: LISP Mapping System Interconnect
6. CPNP Deployment Models
Several CPNP deployment models can be envisaged. Two examples are
listed below:
o The Customer deploys a CPNP client while one or several CPNP
servers are deployed by the Provider.
o The Customer does not enable any CPNP client. The Provider
maintains a Customer Order Management portal. The Customer can
initiate connectivity provisioning quotation orders via the
portal; appropriate CPNP messages are then generated and sent to
the relevant CPNP server. In this model, both the CPNP client and
CPNP server are under the responsibility of the same
administrative entity (i.e., Network Provider).
Once the negotiation of connectivity provisioning parameters is
successfully concluded that is, an order has been placed by the
Customer, the actual network provisioning operations are initiated.
The specification of related dynamic resource allocation and policy
enforcement schemes, as well as how CPNP servers interact with the
network provisioning functional blocks at Provider sides are out of
the scope of this document.
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This document does not make any assumption about the CPNP deployment
model either.
7. CPNP Negotiation Model
CPNP runs between a Customer and a Provider carrying service orders
from the Customer and respective responses from the Provider to the
end of reaching a connectivity service provisioning agreement. As
the services offered by the Provider are well-described, by means of
the CPP template, the negotiation process is essentially a value-
settlement process, where an agreement is pursued on the values of
the commonly understood information items (service parameters)
included in the service description template.
The protocol is transparent to the content that it carries and to the
negotiation logic, at Customer and Provider sides, that manipulates
the content.
The protocol aims at facilitating the execution of the negotiation
logic by providing the required generic communication primitives.
Since negotiations are initiated and primarily driven by the
Customer's negotiation logic, it is reasonable to assume that the
Customer can only call for an agreement. An implicit approach is
adopted for not overloading the protocol with additional messages.
In particular, the acceptance of an offer made by the Provider
signals a call for agreement from the Customer. Note that it is
almost certain the Provider to accept this call since it refers to an
offer that itself made. Of course, at any point the Provider or the
Customer may quit the negotiations, each on its own grounds.
Based on the above, CPNP adopts a Quotation Order/Offer/Answer model,
which proceeds through the following basic steps:
1. The client specifies its service requirements via a Provision
Quotation Order (PQO). The order may include fixed or loosely
defined values in the clauses describing service provisioning
characteristics.
2. The server declines the PQO, or makes an offer to address the
requirements of the PQO, or which may suggests a counter-
proposals that partially addresses the requirements of the PQO
for specific requirements that cannot be accommodated.
3. The client either accepts or declines the offer. Accepting the
offer implies a call for agreement.
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Multiple instances of CPNP may run at Customer or Provider domains.
A CPNP client may be engaged simultaneously in multiple negotiations
with the same or different CPNP servers (parallel negotiations, see
Section 8.11) and a CPNP server may need to negotiate with other
Provider(s) as part of negotiations with a CPNP client (cascaded
negotiations, see Section 8.10).
CPNP relies on various timers to achieve its operations. These
timers are used to guide the negotiation logic at both CPNP client
and CPNP server sides, particularly in cases where the CPNP client is
involved in parallel negotiations with several CPNP servers or in
cases where the CPNP server is, in its turn, involved in negotiations
with other Providers for processing a given quotation order. Related
to the above, CPNP allows the CPNP server to request for more time.
This request may be accepted or rejected by the CPNP client.
Providers may need to publish available services to the Customers
(see Section 4). CPNP may optionally support this functionality.
Dedicated templates can be defined for the purpose of service
announcements, which will be used by the CPNP clients to initiate
their CPNP negotiation cycles.
For simplicity, a single Offer/Answer stage is assumed within one a
CPNP negotiation cycle. Nevertheless, as stated before, multiple
CPNP negotiation cycles can be undertaken by a CPNP client (see
Figure 3).
The model is flexible as it can accommodate changing conditions over
time (e.g., introduction of an additional VPN site).
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+------+ +------+ +------+ +------+
|Client| |Server| |Client| |Server|
+------+ +------+ +------+ +------+
|=====Quotation Order=====>| |=====Quotation Order=====>|
|<==========Offer==========| |<==========Offer==========|
|===========Accept========>| |==========Decline========>|
1-Step Successful Negotiation 1-Step Failed Negotiation
Cycle Cycle
+------+ +------+ +------+ +------+
|Client| |Server| |Client| |Server|
+------+ +------+ +------+ +------+
|===Quotation Order(a)====>| |===Quotation Order(i)====>|
|<==========Offer==========| |<==========Offer==========|
|==========Decline========>| |==========Decline========>|
|===Quotation Order(b)====>| |===Quotation Order(j)====>|
|<==========Offer==========| |<==========Offer==========|
|===========Accept========>| |==========Decline========>|
|===Quotation Order(k)====>|
|<==========Offer==========|
|==========Decline========>|
|===Quotation Order(l)====>|
|<==Fail to make an offer==|
N-Step Negotiation Cycle: N-Step Negotiation Cycle:
Successful Negotiation Failed Negotiation
Figure 3: Overall Negotiation Process
8. Protocol Overview
8.1. Client/Server Communication
CPNP is a client/server protocol which is designed to run over any
transport protocol with UDP being the default transport mode. No
permanent CPNP session needs to be maintained between the client and
the server. There is no need to run CPNP over a reliable transport
mode because CPNP messages are acknowledged.
The server uses CPNP_PORT (see Section 14) to bind the CPNP service.
The client sends CPNP messages to CPNP_PORT. The same port used as
the source port of the request sent to the server must be used by the
server to reply to that request.
CPNP is independent of the IP address family.
CPNP retransmission is discussed in Section 11.4.
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8.2. Server Discovery
The CPNP client can be configured with the CPNP server(s) using
manual or dynamic configuration means. For example, Providers may
configure dedicated SRV records ([RFC2782]) or may use a well-known
name/address.
Discussions about how the client can discovers its the server(s) of
its interest are out of the scope of this document. The document
assumes that a the required CPNP server can be reached by the CPNP
client, thanks to some configuration means.
8.3. Policy Configuration on the CPNP Server
As an input to its decision-making process, the CPNP server may be
connected to various external modules such as: Customer Profiles,
Network Topology, Network Resource Management, Orders Repository, AAA
and Network Provisioning Manager (an example is shown in Figure 4).
These external modules provide inputs to the CPNP server, so that it
can:
o Check whether a customer is entitled to initiate a provisioning
quotation request.
o Check whether a customer is entitled to cancel an on-going order.
o Check whether administrative data (e.g., billing-related
information) have been verified before starting handling the
request.
o Check whether network capacity is available or additional capacity
is required.
o Receive guidelines from network design and sales blocks (e.g.,
pricing, network usage levels, threshold on number of CPP
templates that can be processed over a given period of time as a
function of the nature of the service to be delivered, etc.).
o Transfer completed orders to network provisioning blocks.
The above list of CPNP server operations is not exhaustive.
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. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
.Business & Administrative Management .
.+------------------------++---------------------------+.
.| Business Guidelines || Billing & Charging |.
.+-----------+------------++-----------+---------------+.
. | | .
. +-------------------+ | .
. . . . . . . . . . . . . . . . .|. . .|. . . . . . . . .
. . . . . . . . . . . . . . . . .|. . .|. . . . . . . . .
.Order Handling Management | | .
. +-------------------+ +-------+-----+--------------+ .
. |Network Topology DB+--+ CPNP Server | .
. +-------------------+ +-+---+---+---+---+-----+----+ .
. | | | | | | .
. +------------------------+-+ | | | | | .
. | Network Dimensioning | | | | | | .
. | & Planning | | | | | | .
. +--------------------------+ | | | | | .
. +----------------------------+-+ | | | +---+----+ .
. | | | | | | AAA | .
. | Network +------------+ | | | +--------+ .
. | Resource | +------------+-+ | +-+----------+ .
. | Management | | Customer | | | Orders | .
. | | | Profiles | | | Repository | .
. +-----------------+ +--------------+ | +------------+ .
. . . . . . . . . . . . . . . . . . . .|. . . . . . . . .
+--------------------------------------+----------------+
| Network Provisioning Manager |
+-------------------------------------------------------+
Figure 4: Order Handling Management Functional Block
The following order handling modes can be also configured on the
server:
1. Fully automated mode:
This mode does not require any action from the administrator when
receiving a request for a service. The server can execute its
decision-making process related to the orders received and
generate corresponding offers.
2. Administrative validation checking:
Some or all of the server's operations are subject to
administrative validation procedures. This mode requires an
action from the administrator for every request received. The
CPNP methods which can be automatically handled by the server or
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they are subject to one or several validation administrative
checks can be configured on the server.
8.4. CPNP Session
Both the client and server maintain the following CPNP transport
session information:
A CPNP session is identified by the following items:
o IP address of the client
o Client's port number
o IP address of the server
o Server's port number
8.5. Extended CPNP Session
An extended PQO session is denoted by a 5-uplet defined as follows:
o CPNP session (Section 8.4)
o Incremented Sequence Number (Section 11.3)
o Customer Agreement Identifier: This is a unique identifier
assigned to the order under negotiation by the client
(Section 9.1.1). This identifier is also used to identify the
agreement that will result from a successful negotiation.
o Provider Agreement Identifier: This is a unique identifier
assigned to the order under negotiation by the server
(Section 9.1.2). This identifier is also used to identify the
agreement that will result from a successful negotiation.
o Transaction-ID (Section 9.1.3)
8.6. CPNP Transaction
A CPNP transaction occurs between a client and a server for pursuing,
modifying, withdrawing a service agreement and comprises all CPNP
messages exchanged between the client and the server, from the first
request sent by the client to the final response sent by the server.
A CPNP transaction is bound to a CPNP session.
Because multiple CPNP transactions can be maintained by the CPNP
client, the client must assign an identifier to uniquely identify a
given transaction. This identifier is denoted as Transaction-ID.
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The Transaction-ID must be randomly assigned by the CPNP client,
according to the best current practice for generating random numbers
[RFC4086] that cannot be guessed easily. Transaction-ID is used for
validating CPNP responses received by the client.
In the context of a transaction, the client needs to randomly select
a sequence number and assign it in the first CPNP message to send.
This number is then incremented for each request message is
subsequently sent within the on-going CPNP transaction (see
Section 11.3).
8.7. CPNP Timers
CPNP adopts a simple retransmission procedure which relies on a
retransmission timer denoted as RETRANS_TIMER and maximum retry
threshold. The use of RETRANS_TIMER and a maximum retry threshold
are described in Section 11.
The response timer (RESPONSE_TIMER) is set by the client to denote
the time, in seconds, the client will wait for receiving a response
from the server to a provisioning quotation order request (see
Section 9.1.6). If the timer expires, the respective quotation order
is cancelled by the client and a CANCEL message is generated
accordingly.
An offer expiration timer (EXPIRE_TIMER) is set by the server to
represent the time, in minutes, after which an offer made by the
server will be invalid (see Section 9.1.8).
8.8. CPNP Operations
The current CPNP operations are listed below. They may be augmented,
depending on the nature of some transactions or because of security
considerations that may necessitate a distinct CPNP client/server
authentication phase before negotiation begins.
o QUOTATION:
This operation is used by the client to initiate a provisioning
quotation order. Upon receipt of a QUOTATION request, the server
may respond with a PROCESSING, OFFER or a FAIL message. A
QUOTATION-initiated transaction can be terminated by a FAIL
message.
o PROCESSING:
This operation is used to inform the remote party that the message
(the order quotation or the offer) sent was received and it is
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processed. This message can also be issued by the server to
request more time, in which case the client may reply with an ACK
or FAIL message depending on whether more time can or cannot be
granted.
o OFFER:
This operation is used by the server to inform the client about an
offer that can best accommodate the requirements indicated in the
previously received QUOTATION message.
o ACCEPT:
This operation is used by the client to confirm the acceptance of
an offer made by the server. This message implies a call for
agreement. An agreement is reached when an ACK is subsequently
received from the server, which is likely to happen; it is rather
unlikely the server to reject an offer that it has already made.
o ACK:
This operation is used by the server to acknowledge the receipt of
an ACCEPT or WITHDRAW message, or by the client to confirm the
time extension requested by the server for processing the last
received quotation order.
o DECLINE:
This operation is used by the client to reject an offer made by
the server. The on-going transaction may not be terminated
immediately, e.g., the server/client may issue another offer/
order.
o CANCEL:
This operation is used by the client to cancel (quit) the on-going
transaction.
o WITHDRAW:
This operation is used by the client to withdraw an agreement.
o UPDATE:
This operation is used by the client to update an existing
agreement. For example, this method can be invoked to add a new
site. This method will trigger a new negotiation cycle.
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o FAIL:
This operation is used by the server to indicate that it cannot
accommodate the requirements documented in the PQO conveyed in the
QUOTATION message or to inform the client about an error
encountered when processing the received message. In either case,
the message implies that the server is unable to make offers and
as such it terminates the on-going transaction.
This message is also used by the client to reject a time extension
request received from the server (in a PROCESSING message). The
message includes a status code for providing explanatory
information.
Evidently, the above CPNP primitives are service-independent. CPNP
messages may transparently carry service-specific objects which are
handled by the negotiation logic at either side. The document
specifies the service objects that are required for connectivity
provisioning negotiation (see Section 8.9). Additional service-
specific objects to be carried in the CPNP messages can be defined in
the future for accommodating alternative deployment or other service
provisioning needs.
8.9. Connectivity Provisioning Documents
CPNP makes use of several flavors of Connectivity Provisioning
Documents (CPD). These documents follow the CPP template described
in [RFC7297].
o Requested Connectivity Provisioning Document (Requested CPD):
refers to the CPD included by a CPNP client in a QUOTATION
request.
o Offered Connectivity Provisioning Document (Offered CPD):
This document is included by a CPNP server in an OFFER message.
Its information reflects the proposal of the server to accommodate
all or a subset of the clauses depicted in a Requested CPD. A
validity time is associated with the offer made.
o Agreed Connectivity Provisioning Document (Agreed CPD):
If the client accepts an offer made by the server, the Offered CPD
is included in an ACCEPT message. This CPD is also included in an
ACK message. Thus, a 3-way hand-shaking procedure is followed for
successfully concluding the negotiation.
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Figure 5 shows a typical CPNP negotiation cycle and the use of the
different types of Connectivity Provisioning Documents.
+------+ +------+
|Client| |Server|
+------+ +------+
|======QUOTATION (Requested CPD)=====>|
|<============PROCESSING==============|
|<========OFFER (Offered CPD)=========|
|=============PROCESSING=============>|
|=========ACCEPT (Agreed CPD)========>|
|<=========ACK (Agreed CPD)===========|
Figure 5: Connectivity Provisioning Documents
A provisioning document can include parameters with fixed values,
loosely defined values, or a combination thereof. A provisioning
document is said to be concrete if all clauses have fixed values.
A typical evolution of a negotiation cycle would start with a
quotation order with loosely defined parameters, and then, as offers
are made, it would conclude with concrete provisioning document for
calling for the agreement.
8.10. Child Provisioning Quotation Orders
If the server detects that network resources from another Network
Provider need to be allocated in order to accommodate the
requirements described in a PQO (e.g., in the context of an inter-
domain VPN service, additional PE router resources need to be
allocated), the server may generate child PQOs to request the
appropriate network provisioning operations (see Figure 6). In such
situation, the server behaves also as a CPNP client. The server
associates the parent order with its child PQOs. This is typically
achieved by locally adding the reference of the child PQO to the
parent order.
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+------+ +--------+ +--------+
|Client| |Server A| |Server B|
+------+ +--------+ +--------+
| | |
|=====QUOTATION=====>| |
|<====PROCESSING=====| |
| |=====QUOTATION=====>|
| |<====PROCESSING=====|
| |<=======OFFER=======|
| |=====PROCESSING====>|
| |=======ACCEPT======>|
| |<=======ACK=========|
|<=======OFFER=======| |
|=====PROCESSING====>| |
|=======ACCEPT======>| |
|<=======ACK=========| |
Figure 6: Example of Child Orders
8.11. Negotiations with Multiple CPNP Servers
A CPNP client may undertake multiple negotiations in parallel with
several servers for practical reasons such as cost optimization and
fail-safety. The multiple negotiations may lead to one or many
agreements. Multiple negotiations with the same Provider are not
precluded.
The salient point underlining the parallel negotiations scenario is
that although the negotiation protocol is strictly between two
parties, the negotiation logic may not necessarily be. The CPNP
client negotiation logic may need to collectively drive parallel
negotiations, as the negotiation with one server may affect the
negotiation with other servers; e.g., it may need to use the
responses from all servers as input for determining the messages (and
their content) to subsequently send in each individual negotiation.
Timing is therefore an important aspect at the client's. The CPNP
client needs to have the ability to synchronize the receipt of the
responses from the servers. CPNP takes into account this requirement
by allowing clients to specify in the QUOTATION message the time by
which the server needs to respond (see Section 9.1.6).
8.12. State Management
Both the client and the server maintain repositories to store on-
going orders. How these repositories are maintained is deployment-
specific. It is out of scope of this document to elaborate on such
considerations. Timestamps are also logged to track state change.
Tracking may be needed for various reasons,including regulatory ones.
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8.12.1. On the Client Side
The following lists the states which can be associated with a given
order on the client's side:
o Created:
when the order has been created. It is not handled by the client
until the administrator allows to process it.
o AwaitingProcessing:
when the administrator approved of processing a created order and
the order has not been handled yet.
o PQOSent:
when the order has been sent to the server.
o ServerProcessing:
when the server has confirmed the receipt of the order.
o OfferReceived:
when an offer has been received from the server.
o OfferProcessing:
when a received offer is currently processed by the client.
o AcceptSent:
when the client confirmed the offer to the server.
o AcceptAck:
when the offer is acknowledged by the server.
o Cancelled:
when the order has failed or cancelled.
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+------------------+
| Created |-----------------+
+------------------+ |
| |
v |
+------------------+ |
|AwaitingProcessing|----------------+|
+------------------+ ||
| ||
QUOTATION ||
v ||
+------------------+ ||
| PQOSent |---CANCEL------+||
+------------------+ vvv
| +-----+
PROCESSING | |
v | |
+------------------+ CANCEL | C |
| ServerProcessing |------------>| A |
+------------------+ FAIL | N |
| | C |
| | E |
OFFER | L |
| | L |
v | E |
+------------------+ | D |
| OfferReceived |---CANCEL--->| |
+------------------+ | |
| PROCESSING +-----+
v ^^^
+------------------+ |||
| OfferProcessing |---DECLINE-----+||
+------------------+ ||
| ACCEPT ||
v ||
+------------------+ ||
| AcceptSent |---CANCEL-------+|
+------------------+ |
| ACK |
v |
+------------------+ |
| AcceptAck |---WITHDRAW------+
+------------------+
Figure 7: CPNP Finite State Machine (Client Side)
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8.12.2. On the Server Side
The following lists the states which can be associated with a given
order and a corresponding offer on the server's side:
o PQOReceived:
when the order has been received from the client.
o AwaitingProcessing:
when the order is being processed by the server. An action from
the server administrator may be needed.
o OfferProposed:
when the request has been successfully handled and an offer has
been sent to the client.
o ProcessingReceived:
when the server received a PROCESSING for an offer sent to the
client.
o AcceptReceived:
when the server received a confirmation for the offer from the
client.
o AcceptAck:
when the server acknowledged the offer (accepted by client) to the
client.
o Cancelled:
when the order has failed to be met or it has been cancelled by
the client. Associate resources must be released in the latter
case, if prior reserved.
o ChildCreated:
when a child order has been created in cases where resources from
another Network Provider are needed.
o ChildPQOSent:
when a child order has been sent to the remote server.
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o ChildServerProcessing:
when a child order is currently processed by the remote server.
o ChildOfferReceived:
when an offer has been received to a child order from the remote
server.
o ChildOfferProcessing:
when a received offer to a child order is currently processed.
o ChildAcceptSent:
when the child offer (offer received from the remote server in
response to a child order) is confirmed to the remote server.
o ChildAcceptAck:
when an accepted child offer is acknowledged by the remote server.
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+------------------+
+---------------------| ChildCreated |
| +------------------+
v | ^
+------------------+ | |
| ChildPQOSent |----------------+| Q
+------------------+ || U
| || O
QUOTATION || T
v || A +--------------------+
+---------------------+ CANCEL || T | PQOReceived |
|ChildServerProcessing|------------+|| I +--------------------+
+---------------------+ FAIL vvv O | |
| +-----+ N CANCEL |
PROCESSING | |<---|-------+ PROCESSING
v | | | v
+------------------+ | | +------------------------+
|ChildOfferReceived|----CANCEL---| C |<--| AwaitingProcessing |
+------------------+ | A | +------------------------+
| | N | ^ | OFFER
OFFER | C | | +------------------+
| | E |<DECLINE-| OfferProposed |
| | L | | +------------------+
v | L | | |
+------------------+ | E | | PROCESSING
|ChildOfferReceived|---CANCEL----| D | | v
+------------------+ | | | +------------------+
| | |<DECLINE-| Proc'ingReceived |
PROCESSING | | +------------------+
| +-----+ | | ACCEPT
v ^^^^^ | v
+------------------+ ||||| | +------------------+
|ChildOfferProc'ing|---DECLINE----+|||+-CANCEL-|-| AcceptReceived |
+------------------+ ||| | +------------------+
|ACCEPT ||| | |ACK
v ||| | v
+------------------+ ||| | +------------------+
| ChildAcceptSent |---CANCEL------+|+-WITHDRAW|-| AcceptAck |
+------------------+ | | +------------------+
| ACK | |
v | |
+------------------+ | |
| ChildAcceptAck |---WITHDRAW-----+ |
+------------------+ |
| |
+--------------------------------------+
Figure 8: CPNP Finite State Machine (Server Side)
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9. CPNP Objects
This section defines CPNP objects using the RBNF format defined at
[RFC5511].
Note: The formats of CPNP messages are provided using a generic
format. Implementors can adapt RBNF definitions to their
"favourite" message format.
This document focuses on connectivity provisioning objects;
additional Information Elements (IEs) can be defined in the future.
9.1. Attributes
9.1.1. CUSTOMER_AGREEMENT_IDENTIFIER
CUSTOMER_AGREEMENT_IDENTIFIER is an identifier which is assigned by a
client to identify an agreement. This identifier must be unique to
the client.
Rules for assigning this identifier are specific to the client
(Customer). The value of CUSTOMER_AGREEMENT_IDENTIFIER is included
in all CPNP messages.
The client (Customer) assigns an identifier to an order under
negotiation before an agreement is reached. This identifier will be
used to unambiguously identify the resulting agreement at the client
side (Customer).
The server handles CUSTOMER_AGREEMENT_IDENTIFIER as an opaque value.
9.1.2. PROVIDER_AGREEMENT_IDENTIFIER
PROVIDER_AGREEMENT_IDENTIFIER is an identifier which is assigned by a
server to identify an order. This identifier must be unique to the
server.
Rules for assigning this identifier are specific to the server
(Provider). The value of PROVIDER_AGREEMENT_IDENTIFIER is included
in all CPNP messages, except QUOTATION messages.
The server (Provider) assigns an identifier to an order under
negotiation before an agreement is reached. This identifier will be
used to unambiguously identify the resulting agreement at the server
side (Provider).
The client handles PROVIDER_AGREEMENT_IDENTIFIER as an opaque value.
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9.1.3. TRANSACTION_ID
This object conveys the Transaction-ID introduced in Section 8.6.
9.1.4. SEQUENCE_NUMBER
Sequence Number is a number that is monotonically incremented on
every new CPNP message within a CPNP transaction. This number is
used to avoid reply attacks.
Refer to Section 11.3.
9.1.5. NONCE
NONCE is a random value assigned by the CPNP server. It is
RECOMMENDED to assign unique NONCE values for each order.
NONCE is then mandatory to be included in subsequent CPNP client
operations on the associated order (including the resulting
agreement) such as: withdraw the order or update the order.
If the NONCE validation checks fail, the server rejects the request
with a FAIL message including the appropriate failure reason code.
9.1.6. EXPECTED_RESPONSE_TIME
This attribute indicates the time by when the CPNP client is
expecting to receive a response, for a PQO, from the CPNP server. If
no offer is received by then, the CPNP client will consider the
quotation order as rejected.
EXPECTED_RESPONSE_TIME follows the date format specified in
[RFC1123].
9.1.7. EXPECTED_OFFER_TIME
This attribute indicates the time by when the CPNP server is
expecting to make an offer to the CPNP client. If no offer is
received by then, the CPNP client will consider the order as
rejected.
The CPNP server may propose an expected offer time that does not
match the expected response time indicated in the quotation order
message. The CPNP client can accept or rejects the proposed expected
time by when the CPNP server will make an offer.
The CPNP server can always request extra time for its processing, but
this may be accepted or rejected by the CPNP client.
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EXPECTED_OFFER_TIME follows the date format specified in [RFC1123].
9.1.8. VALIDITY_OFFER_TIME
This attribute indicates the time of validity of an offer made by the
CPNP server. If the offer is not accepted before this date expires,
the CPNP server will consider the CPNP client has rejected the offer;
the CPNP server will silently clear this order.
VALIDITY_OFFER_TIME follows date format specified in [RFC1123].
9.1.9. CONNECTIVITY_PROVISIONING_DOCUMENT
The RBNF format of the Connectivity Provisioning Document is shown
below:
<CONNECTIVITY_PROVISIONING_DOCUMENT> ::=
<Connectivity Provisioning Component> ...
<Connectivity Provisioning Component> ::=
<CONNECTIVITY_PROVISIONING_PROFILE> ...
<CONNECTIVITY_PROVISIONING_PROFILE> ::=
<Customer Nodes Map>
<SCOPE>
<QoS Guarantees>
<Availability>
<CAPACITY>
<Traffic Isolation>
<Conformance Traffic>
<Flow Identification>
<Overall Traffic Guarantees>
<Routing and Forwarding>
<Activation Means>
<Invocation Means>
<Notifications>
<Customer Nodes Map> ::= <Customer Node> ...
<Customer Node> ::= <IDENTIFIER>
<LINK_IDENTIFIER>
<LOCALISATION>
9.1.10. Information Elements
An Information Element (IE) is an optional object which can be
included in a CPNP message.
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9.1.10.1. Customer Description
The client may include administrative information such as:
o Name
o Contact Information
The format of this Information Element is as follows:
<Customer Description> ::= <NAME> <Contact Information>
<Contact Information> ::= <EMAIL_ADDRESS> [<POSTAL_ADDRESS>]
[<TELEPHONE_NUMBER> ...]
9.1.10.2. Provider Description
The server may include administrative information in an offer such
as:
o Name
o AS Number ([RFC6793])
o Contact Information
The format of this Information Element is as follows:
<Provider Description> ::= <NAME><Contact Information>[<AS_NUMBER>]
9.1.10.3. Negotiation Options
The client may include some negotiation options such as:
o Cost: the client may include an empty or a preferred COST
attribute to request the cost from the server. The server will
provide the cost information in the response.
o Setup purpose: A client may request to setup a connectivity only
for testing purposes during a limited period. The order can be
extended to become permanent if the client was satisfied during
the test period. This operation is achieved using UPDATE method.
Other negotiation options may be defined in the future.
The format of this Information Element is as follows:
<Negotiation Options> ::= [<COST>][<PURPOSE>]
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9.2. Operation Messages
This section specifies the RBNF format of CPNP operation messages.
9.2.1. QUOTATION
The format of the QUOTATION message is shown below:
<QUOTATION Message> ::= <VERSION>
<METHOD_CODE>
<SEQUENCE_NUMBER>
<TRANSACTION_ID>
<CUSTOMER_AGREEMENT_IDENTIFIER>
[<EXPECTED_RESPONSE_TIME>]
<REQUESTED_CONNECTIVITY_PROVISIONING_DOCUMENT>
[<INFORMATION_ELEMENT>...]
A QUOTATION message must include an order identifier which is
generated by the client. Because several orders can be issued to
several servers, the QUOTATION message must also include a
Transaction-ID.
The message may include an EXPECTED_RESPONSE_TIME which indicates by
when the client is expecting to receive an offer from the server.
QUOTATION message must also include a requested connectivity
provisioning document.
When the client sends the QUOTATION message to the server, the state
of the order changes to "PQOSent".
9.2.2. PROCESSING
The format of the PROCESSING message is shown below:
<PROCESSING Message> ::= <VERSION>
<METHOD_CODE>
<SEQUENCE_NUMBER>
<TRANSACTION_ID>
<CUSTOMER_AGREEMENT_IDENTIFIER>
<PROVIDER_AGREEMENT_IDENTIFIER>
[<EXPECTED_OFFER_TIME>]
Upon receipt of a QUOTATION message, the server proceeds with parsing
rules (see Section 10). If no error is encountered, the server
generates a PROCESSING response to the client to indicate the PQO has
been received and it is being processed. The server must generate an
order identifier which identifies the order in its local order
repository. The server MUST copy the content of
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CUSTOMER_AGREEMENT_IDENTIFIER and TRANSACTION_ID fields as conveyed
in the QUOTATION message. The server may include an
EXPECTED_OFFER_TIME by when it expects to make an offer to the
client.
Upon receipt of a PROCESSING message, the client verifies whether it
has issued a PQO to that server and which contains the
CUSTOMER_AGREEMENT_IDENTIFIER and TRANSACTION_ID. If no such PQO is
found, the PROCESSING message is silently ignored. If a PQO is
found, the client may check if it accepts the EXPECTED_OFFER_TIME and
then, it changes to state of the order to "ServerProcessing".
If more time is required by the server to process the quotation
order, it may send a PROCESSING message that includes a new
EXPECTED_OFFER_TIME. The client can answer with an ACK message if
more time is granted (Figure 9) or with a FAIL message if the time
extension is rejected (Figure 10).
+------+ +------+
|Client| |Server|
+------+ +------+
|=======QUOTATION(Requested CPD)=====>|
|<========PROCESSING(time1)===========|
...
|<========PROCESSING(MoreTime)========|
|============ACK(TimeGranted)========>|
...
|<=========OFFER(Offered CPD)=========|
|=============PROCESSING=============>|
|==========ACCEPT(Agreed CPD)========>|
|<==========ACK(Agreed CPD)===========|
Figure 9: Request more negotiation time: Granted
+------+ +------+
|Client| |Server|
+------+ +------+
|=======QUOTATION(Requested CPD)=====>|
|<========PROCESSING(time1)===========|
...
|<========PROCESSING(MoreTime)========|
|===========FAIL(TimeRejected)=======>|
Figure 10: Request more negotiation time: Rejected
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9.2.3. OFFER
The format of the OFFER message is shown below:
<OFFER Message> ::= <VERSION>
<METHOD_CODE>
<SEQUENCE_NUMBER>
<TRANSACTION_ID>
<CUSTOMER_AGREEMENT_IDENTIFIER>
<PROVIDER_AGREEMENT_IDENTIFIER>
<NONCE>
<VALIDITY_OFFER_TIME>
<OFFERED_CONNECTIVITY_PROVISIONING_DOCUMENT>
[<INFORMATION_ELEMENT>...]
The server answers with an OFFER message to a QUOTATION request
received from the client. The offer will be considered as rejected
by the client if no confirmation (ACCEPT message sent by the client)
is received by the server before the expiration of the validity time.
9.2.4. ACCEPT
The format of the ACCEPT message is shown below:
<ACCEPT Message> ::= <VERSION>
<METHOD_CODE>
<SEQUENCE_NUMBER>
<TRANSACTION_ID>
<CUSTOMER_AGREEMENT_IDENTIFIER>
<PROVIDER_AGREEMENT_IDENTIFIER>
<NONCE>
<AGREED_CONNECTIVITY_PROVISIONING_DOCUMENT>
[<INFORMATION_ELEMENT>...]
This message is used by a client to confirm the acceptance of an
offer received from a server. The fields of this message are copied
from the received OFFER message.
9.2.5. ACK
The format of the ACK message is shown below:
<ACK Message> ::= <VERSION>
<METHOD_CODE>
<SEQUENCE_NUMBER>
<TRANSACTION_ID>
<CUSTOMER_AGREEMENT_IDENTIFIER>
<PROVIDER_AGREEMENT_IDENTIFIER>
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[<EXPECTED_RESPONSE_TIME>]
[<CONNECTIVITY_PROVISIONING_DOCUMENT>]
[<INFORMATION_ELEMENT>...]
This message is issued by the server to close a CPNP transaction or
by a client to grant more negotiation time to the server.
This message is sent by the server as a response to an ACCEPT,
WITHDRAW, DECLINE, or CANCEL message. In such case, the ACK message
must include the copy of the Connectivity Provisioning Document as
stored by the server, in particular:
o A copy of the requested/offered CPD is included by the server if
it successfully handled a CANCEL message.
o A copy of the updated CPD is included by the server if it
successfully handled an UPDATE message.
o A copy of the offered CPD is included by the server if it
successfully handled an ACCEPT message in the context of a
QUOTATION transaction.
o An empty CPD is included by the server if it successfully handled
a DECLINE message.
A client may issue an ACK message as a response to a more time
request (conveyed in PROCESSING) received from the server. In such
case, the ACK message must include an EXPECTED_RESPONSE_TIME that is
likely to be set to the time extension requested by the server.
9.2.6. DECLINE
The format of the DECLINE message is shown below:
<DECLINE Message> ::= <VERSION>
<METHOD_CODE>
<SEQUENCE_NUMBER>
<TRANSACTION_ID>
<CUSTOMER_AGREEMENT_IDENTIFIER>
<PROVIDER_AGREEMENT_IDENTIFIER>
<NONCE>
The client can issue a DECLINE message to reject an offer.
CUSTOMER_AGREEMENT_IDENTIFIER, PROVIDER_AGREEMENT_IDENTIFIER,
TRANSACTION_ID, and NONCE are used by the server as keys to find the
corresponding order. If an order matches, the server changes the
state of this order to "Cancelled" and then returns an ACK with a
copy of the requested CPD to the requesting client.
If no order is found, the server returns a FAIL message to the
requesting client.
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A flow example is shown in Figure 11.
+------+ +------+
|Client| |Server|
+------+ +------+
|=======QUOTATION(Requested CPD)=====>|
|<============PROCESSING==============|
|<=========OFFER(Offered CPD)=========|
|=============PROCESSING=============>|
|===============DECLINE==============>|
|<================ACK=================|
Figure 11: DECLINE Flow Example
9.2.7. CANCEL
The format of the CANCEL message is shown below:
<CANCEL Message> ::= <VERSION>
<METHOD_CODE>
<SEQUENCE_NUMBER>
<TRANSACTION_ID>
<CUSTOMER_AGREEMENT_IDENTIFIER>
[<CONNECTIVITY_PROVISIONING_DOCUMENT>]
The client can issue a CANCEL message at any stage during the CPNP
negotiation process before an agreement is reached.
CUSTOMER_AGREEMENT_IDENTIFIER and TRANSACTION_ID are used by the
server as keys to find the corresponding order. If a quotation order
matches, the server changes the state of this quotation order to
"Cancelled" and then returns an ACK with a copy of the requested CPD
to the requesting client.
If no quotation order is found, the server returns a FAIL message to
the requesting client.
9.2.8. WITHDRAW
The format of the WITHDRAW message is shown below:
<WITHDRAW Message> ::= <VERSION>
<METHOD_CODE>
<SEQUENCE_NUMBER>
<TRANSACTION_ID>
<CUSTOMER_AGREEMENT_IDENTIFIER>
<PROVIDER_AGREEMENT_IDENTIFIER>
<NONCE>
[<AGREED_CONNECTIVITY_PROVISIONING_DOCUMENT>]
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[<INFORMATION_ELEMENT>...]
This message is used to withdraw an offer already subscribed by the
Customer. Figure 12 shows a typical usage of this message.
+------+ +------+
|Client| |Server|
+------+ +------+
|============WITHDRAW(CPD)===========>|
|<============PROCESSING==============|
|<===========ACK(Empty CPD)===========|
Figure 12: WITHDRAW Flow Example
The CPNP must include the same CUSTOMER_AGREEMENT_IDENTIFIER,
PROVIDER_AGREEMENT_IDENTIFIER, and NONCE as those used when creating
the order.
Upon receipt of a WITHDRAW message, the server checks whether an
order matching the request is found. If an order is found, the state
of the order is changed to "Cancelled" and an ACK message including
an Empty CPD is returned to the requesting client. If no order is
found, the server returns a FAIL message to the requesting client.
9.2.9. UPDATE
The format of the UPDATE message is shown below:
<UPDATE Message> ::= <VERSION>
<METHOD_CODE>
<SEQUENCE_NUMBER>
<TRANSACTION_ID>
<CUSTOMER_AGREEMENT_IDENTIFIER>
<PROVIDER_AGREEMENT_IDENTIFIER>
<NONCE>
<EXPECTED_RESPONSE_TIME>
<REQUESTED_CONNECTIVITY_PROVISIONING_DOCUMENT>
[<INFORMATION_ELEMENT>...]
This message is sent by the CPNP client to update an existing
connectivity provisioning agreement. The CPNP must include the same
CUSTOMER_AGREEMENT_IDENTIFIER, PROVIDER_AGREEMENT_IDENTIFIER, and
NONCE as those used when creating the order. The CPNP client
includes a new CPD which integrates the requested modifications. A
new Transaction_ID must be assigned by the client.
Upon receipt of an UPDATE message, the server checks whether an
order, having state "Completed", matches
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CUSTOMER_AGREEMENT_IDENTIFIER, PROVIDER_AGREEMENT_IDENTIFIER, and
NONCE.
o If no order is found, the CPNP server generates a FAIL error with
the appropriate error code.
o If an order is found, the server checks whether it can honor the
request:
* A FAIL message is sent to the client if the server cannot honor
the request. The client may initiate a new PQO negotiation
cycle.
* An OFFER message including the updated connectivity
provisioning document is sent to the client. For example, the
server maintains an order for provisioning a VPN service that
connects sites A, B and C. If the client sends an UPDATE
message to remove site C, only sites A and B will be included
in the OFFER sent by the server to the requesting client.
A flow chart that illustrates the use of UPDATE operation is shown in
Figure 13.
+------+ +------+
|Client| |Server|
+------+ +------+
|=========UPDATE(Requested CPD)======>|
|<============PROCESSING==============|
|<=========OFFER(Updated CPD)=========|
|=============PROCESSING=============>|
|==========ACCEPT(Updated CPD)=======>|
|<==========ACK(Updated CPD)==========|
Figure 13: UPDATE Flow Example
9.2.10. FAIL
The format of the FAIL message is shown below:
<FAIL Message> ::= <VERSION>
<METHOD_CODE>
<SEQUENCE_NUMBER>
<TRANSACTION_ID>
<CUSTOMER_AGREEMENT_IDENTIFIER>
<PROVIDER_AGREEMENT_IDENTIFIER>
<STATUS_CODE>
This message is sent in the following cases:
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o The server can not honor an order received from the client (i.e.,
received in a QUOTATION or UPDATE request).
o The server encounters an error when processing a CPNP request
received from the client.
o The client can not grant more time to a the server. This is a
response to a more time request conveyed in a PROCESSING message.
The status code indicates the error code. The following codes are
currently supported; other codes will be defined in future versions
of the document:
1 (Validation Error): The message can not be validated (see
Section 10).
2 (Authentication Required): the request cannot be handled because
authentication is required.
3 (Authorization Required): the request cannot be handled because
authorization failed.
4 (Administratively prohibited): the request can not be handled
because of administrative policies.
5 (Out of Resources): the request can not be honored because there
is not enough capacity.
6 (Network Presence): the request can not be honored because there
is no network presence.
7 (More Time Rejected): the request to extend the time negotiation
is rejected by the client.
10. Message Validation
Both client and server proceed with CPNP message validation. The
following tables summarize the validation checks to be followed.
10.1. On the Client Side
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Operation Validation Checks
------------ --------------------------------------------------------
PROCESSING {Source IP address, source port, destination IP address,
destination port, Transaction-ID, Customer Order
Identifier} must match an existing PQO with a state set
to "PQOSent". The sequence number carried in the packet
must be larger than the sequence number maintained by
the client.
OFFER {Source IP address, source port, destination IP address,
destination port, Transaction-ID, Customer Order
Identifier} must match an existing order with state set
to "PQOSent" or {Source IP address, source port,
destination IP address, destination port, Transaction-
ID, Customer Order Identifier, Provider Order
Identifier} must match an existing order with a state
set to "ServerProcessing". The sequence number carried
in the packet must be larger than the sequence number
maintained by the client.
ACK {Source IP address, source port, destination IP address,
(QUOTATION destination port, Transaction-ID, Customer Order
Transaction) Identifier, Provider Order Identifier, Offered
Connectivity Provisioning Order} must match an order
with a state set to "AcceptSent". The sequence number
carried in the packet must be larger than the sequence
number maintained by the client.
ACK (UPDATE {Source IP address, source port, destination IP address,
Transaction) destination port, Transaction-ID, Customer Order
Identifier, Provider Order Identifier, Updated
Connectivity Provisioning Order} must match an order
with a state set to "AcceptSent". The sequence number
carried in the packet must be larger than the sequence
number maintained by the client.
ACK {Source IP address, source port, destination IP address,
(WITHDRAW destination port, Transaction-ID, Customer Order
Transaction) Identifier, Provider Order Identifier, Empty
Connectivity Provisioning Order} must match an order
with a state set to "Cancelled". The sequence number
carried in the packet must be larger than the sequence
number maintained by the client.
10.2. On the Server Side
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Method Validation Checks
---------- ----------------------------------------------------------
QUOTATION The source IP address passes existing access filters (if
any). The sequence number carried in the packet must not
be less than the sequence number maintained by the server.
PROCESSING The sequence number carried in the packet must be larger
than the sequence number maintained by the server.
ACCEPT {Source IP address, source port, destination IP address,
destination port, Transaction-ID, Customer Order
Identifier, Provider Order Identifier, Nonce, Offered
Connectivity Provisioning Order} must match an order with
state set to "OfferProposed" or "ProcessngReceived". The
sequence number carried in the packet must be larger than
the sequence number maintained by the server.
DECLINE {Source IP address, source port, destination IP address,
destination port, Transaction-ID, Customer Order
Identifier, Provider Order Identifier, Nonce} must match
an order with state set to "OfferProposed" or
"ProcessngReceived". The sequence number carried in the
packet must be larger than the sequence number maintained
by the server.
UPDATE The source IP address passes existing access filters (if
any) and {Customer Order Identifier, Provider Order
Identifier, Nonce} must match an existing order with state
"Completed".
WITHDRAW The source IP address passes existing access filters (if
any) and {Customer Order Identifier, Provider Order
Identifier, Nonce} must match an existing order with state
"Completed".
11. Theory of Operation
Both CPNP client and server proceeds to message validation checks as
specified in Section 10.
11.1. Client Behavior
11.1.1. Order Negotiation Cycle
To place a provisioning quotation order, the client initiates first a
local quotation order object identified by a unique identifier
assigned by the client. The state of the quotation order is set to
"Created". The client then generates a QUOTATION request which
includes the assigned identifier, possibly an expected response time,
a Transaction-ID and a Requested Connectivity Provisioning Document.
The client may include additional Information Elements such as
Negotiation Options.
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The client may be configured to not enforce negotiation checks on
EXPECTED_OFFER_TIME; if so no EXPECTED_RESPONSE_TIME attribute (or
EXPECTED_RESPONSE_TIME set to infinite) should be included in the
quotation order.
Once the request is sent to the server, the state of the request is
set to "PQOSent" and a timer, if a response time is included in the
quotation order, is set to the expiration time as included in the
QUOTATION request. The client also maintains a copy of the extended
transport session details used to generate the QUOTATION request.
The CPNP client must listen on the same port number that it used to
send the QUOTATION request.
If no answer is received from the server before the retransmission
timer expires (i.e., RETRANS_TIMER, Section 8.7), the client proceeds
to retransmission until maximum retry is reached (i.e., 3 times).
The same sequence number is used for retransmitted packets.
If a FAIL message is received, the client may decide to issue another
(corrected) request towards the same server, cancel the local order,
or contact another server. The behavior of the client depends on the
error code returned by the server in the FAIL message.
If a PROCESSING message matching the CPNP transport session is
received, the client updates the CPNP session with the
PROVIDER_AGREEMENT_IDENTIFIER information. If the client does not
accept the expected offer time that may have been indicated in the
PROCESSING message, the client may decide to cancel the quotation
order. If the client accepts the EXPECTED_OFFER_TIME, it changes the
state of the order to "ServerProcessing" and sets a timer to the
value of EXPECTED_OFFER_TIME. If no offer is made before the timer
expires, the client changes the state of the order to "Cancelled".
As a response to a more time request (conveyed in a PROCESSING
message that included a new EXPECTED_OFFER_TIME), the client may
grant this extension by issuing an ACK message or reject the time
extension with a FAIL message having a status code set to "More Time
Rejected".
If an OFFER message matching the extended CPNP session is received,
the client checks if a PROCESSING message having the same
PROVIDER_AGREEMENT_IDENTIFIER has been received from the server. If
a PROCESSING message was already received for the same order but the
PROVIDER_AGREEMENT_IDENTIFIER does not match the identifier included
in the OFFER message, the client ignores silently the message. If a
PROCESSING message having the same PROVIDER_AGREEMENT_IDENTIFIER was
already received and matches the CPNP transaction identifier, the
client changes the state of the order to "OfferReceived" and sets a
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timer to the value of VALIDITY_OFFER_TIME indicated in the OFFER
message.
If an offer is received from the server (i.e., as documented in an
OFFER message), the client may accept or reject the offer. The
client accepts the offer by generating an ACCEPT message which
confirms that the client agrees to subscribe to the offer documented
in the OFFER message; the state of the order is passed to
"AcceptSent". The transaction is terminated if an ACK message is
received from the server. If no ACK is received from the server, the
client proceeds with the re-transmission of the ACCEPT message.
The client may also decide to reject the offer by sending a DECLINE
message. The state of the order is set by the client to "Cancelled".
If an offer is not acceptable by the client, the client may decide to
contact a new server or submit another order to the same server.
Guidelines to issue an updated order or terminate the negotiation are
specific to the client.
11.1.2. Order Withdrawal Cycle
A client may withdraw a completed order. This is achieved by issuing
a WITHDRAW message. This message must include Customer Order
Identifier, Provider Identifier and Nonce returned during the order
negotiation cycle specified in Section 11.1.1.
If no ACK is received from the server, the client proceeds with the
re-transmission of the message.
11.1.3. Order Update Cycle
A client may update a completed order. This is achieved by issuing
an UPDATE message. This message must include Customer Order
Identifier, Provider Order Identifier and Nonce returned during the
order negotiation cycle specified in Section 11.1.1. The client must
include in the UPDATE message an updated CPD with the requested
changes.
Subsequent messages exchange is similar to what is documented in
Section 11.1.1.
11.2. Server Behavior
11.2.1. Order Processing
Upon receipt of a QUOTATION message from a client, the server sets a
CPNP session, stores Transaction-ID and generates a Provider Order
Identifier. Once preliminary validation checks are completed (
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Section 10), the server may return a PROCESSING message to notify the
client the quotation order is received and it is under processing;
the server may include an expected offer time to notify the client by
when an offer will be proposed. An order with state
"AwaitingProcessing" is created by the server. The server runs its
decision-making process to decide which offer it can make to honor
the received order. The offer should be made before the expected
offer time expires.
If the server cannot make an offer, it sends backs a FAIL message
with the appropriate error code.
If the server requires more negotiation time, it must send a
PROCESSING message with a new EXPECTED_OFFER_TIME. The client may
grant this extension by issuing an ACK message or reject the time
extension with a FAIL message having a status code set to "More Time
Rejected". If the client doesn't grant more time, the server must
answer before the initial expected offer time; otherwise the client
will ignore the quotation order.
If the server can honor the request or it can make an offer that meet
some of the requirements, it creates an OFFER message. The server
must indicate the Transaction-ID, Customer Order Identifier as
indicated in the QUOTATION message, and the Provider Order Identifier
generated for this order. The server must also include Nonce and the
offered Connectivity Provisioning Document. The server includes an
offer validity time as well. Once sent to the client, the server
changes the state of the order to "OfferSent" and a timer set to the
validity time is initiated.
If the server determines that additional network resources from
another network provider are needed to accommodate a quotation order,
it will create child PQO(s) and will behave as a CPNP client to
negotiate child PQO(s) with possible partnering providers (see
Figure 6).
If no PROCESSING, ACCEPT or DECLINE message is received before the
expiry of the RETRANS_TIMER, the server re-sends the same offer to
the client. This procedure is repeated until maximum retry is
reached.
If an ACCEPT message is received before the offered validity time
expires, the server proceeds with validation checks as specified in
Section 10. The state of the corresponding order is passed to
"AcceptReceived". The server sends back an ACK message to terminate
the order processing cycle.
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If a CANCEL/DECLINE message is received, the server proceeds with the
cancellation of the order. The state of the order is then passed to
"Cancelled".
11.2.2. Order Withdrawal
A client may withdraw a completed order by issuing a WITHDRAW
message. Upon receipt of a WITHDRAW message, the server proceeds
with the validation checks, as specified in Section 10.
o If the checks fail, a FAIL message is sent back to the client with
the appropriate error code.
o If the checks succeed, the server clears the clauses of the
Connectivity Provisioning Document, changes the state of the order
to "Cancelled", and sends back an ACK message with an Empty
Connectivity Provisioning Document.
11.2.3. Order Update
A client may update an order by issuing an UPDATE message. Upon
receipt of an UPDATE message, the server proceeds with the validation
checks as specified in Section 10.
o If the checks fail, a FAIL message is sent back to the client with
the appropriate error code.
o Subsequent messages exchange is similar to what is specified in
Section 11.1.1. The server should generate a new Nonce value to
be included in the offer made to the client.
11.3. Sequence Numbers
In each transaction, sequence numbers are used to protect the
transaction against replay attacks. Each communicating partner of
the transaction maintains two sequence numbers, one for incoming
packets and one for outgoing packets. When a partner receives a
message, it will check whether the sequence number in the message is
larger than the incoming sequence number maintained locally. If not,
the messages will be discarded. If the message is proved to be
legal, the value of the incoming sequence number will be replaced by
the value of the sequence number in the message. When a partner
sends out a message, it will insert the value of outgoing sequence
number into the message and increase the outgoing sequence number
maintained locally by 1.
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11.4. Message Re-Transmission
If a transaction partner sends out a message and does not receive any
expected reply before the retransmission timer expires (i.e.,
RETRANS_TIMER), a transaction partner will try to re-transit the
messages. An exception is the last message (e.g., ACK) sent from the
server in a transaction. After sending this message, the
retransmission timer will be disabled since no additional feedback is
expected.
In addition, if the partner receives a re-sent last incoming packet,
the partner can also send out the answer to the incoming packet with
a limited frequency. If no answer was generated at the moment, the
partner needs to generate a PROCESSING message as the answer.
To benefit message re-transmission, a partner could also store the
last incoming packet and the associated answer. Note that the times
of re-transmission could be decided by the local policy and re-
transmission will not cause any change of sequence numbers.
12. Operational Guidelines
12.1. Logging on the CPNP Server
The CPNP server SHOULD be configurable to log various events and
associated information. Such information includes:
o Client's IP Address
o Any event change (e.g., new quotation order, offer sent, order
confirm, order cancellation, order withdraw, etc.)
o Timestamp
12.2. Business Guidelines & Objectives
The CPNP server can operate in the following modes:
1. Fully automated mode: The CPNP server is provisioned with a set
of business guidelines and objectives that will be used as an
input to the decision-making process. The CPNP server will
service received orders that falls into these business
guidelines; otherwise requests will be escalated to an
administrator that will formally validate/invalidate an order
request. The set of policies to be configured to the CPNP server
are specific to each administrative entity managing a CPNP
server.
2. Administrative-based mode: This mode assumes some or all CPNP
server' operations are subject to a formal administrative
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validation. CPNP events will trigger appropriate validation
requests that will be forwarded to the contact person(s) or
department which is responsible for validating the orders.
Administrative validation messages are relayed using another
protocol (e.g., SMTP) or a dedicated tool.
Business guidelines are local to each administrative entity. How
validation requests are presented to an administrator are out of
scope of this document; each administrative entity may decide the
appropriate mechanism to enable for that purpose.
13. Security Considerations
Means to defend the server against denial-of-service attacks must be
enabled. For example, access control lists (ACLs) can be enforced on
the client, the server or the network in between, to allow a trusted
client to communicate with a trusted server.
The client and the server should be mutually authenticated. Out of
band mechanisms can be used instead of integrating them into CPNP.
The client must silently discard CPNP responses received from unknown
CPNP servers. The use of a randomly generated Transaction-ID makes
it hard to forge a response from a server with a spoofed IP address
belonging to a legitimate CPNP server. Furthermore, CPNP demands
that messages from the server must include correct identifiers of the
orders. Two order identifiers are used: one generated by the client
and a second one generated by the server.
The Provider must enforce means to protect privacy-related
information included the documents (see Section 8.9) exchanged using
CPNP messages [RFC6462]. In particular, this information must not be
revealed to external parties without the consent of Customers.
Providers should enforce policies to make Customer fingerprinting
difficult to achieve. For more discussion about privacy, refer to
[RFC6462][RFC6973].
The NONCE and the Transaction ID attributes provide sufficient
randomness and can effectively tolerate attacks raised by off-line
adversaries, who do not have the capability of eavesdropping and
intercepting the packets transported between the client and the
server. Only authorized clients must be able to modify agreed CPNP
orders. The use of a randomly generated NONCE by the server makes it
hard to modify an agreement on behalf of a malicious third-party.
The sequence numbers included in the CPNP messages can be used to
detect replay attacks and antique packets intercepted from on-going
transactions may be re-sent. However, the protocol in its current
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version may be vulnerable to replay attacks where the replayed
messages are intercepted from antique transactions. Although the
Transaction ID provided by the client could protect inter-transaction
replay attacks, no protection is provided for the server to deal with
this type of attack.
The protocol does not provide security mechanisms to protect the
confidentiality and integrity of the packets transported between the
client and the server. An underlying security protocol such as
(e.g., DTLS [RFC6347], IPsec) could be used to protect the integrity
and confidentiality for the protocol. In this case, if it is
possible to provide an Automated Key Management (AKM) and associate
each transaction with a different key, inter- transaction replay
attacks can naturally be addressed. If the client and the server use
a single key, an additional mechanism should be provided to protect
inter-transaction replay attacks between them.
The deployment option of a Customer Order Management portal operated
by a trusted third-party (see Section 6) may facilitate the efficient
resolution of the aforementioned security concerns.
14. IANA Considerations
Authors of the document request IANA to assign a UDP port for CPNP.
A registry for CPNP methods should be created. The following codes
are reserved:
1: QUOTATION
2: PROCESSING
3: OFFER
4: ACCEPT
5: DECLINE
6: ACK
7: CANCEL
8: WITHDRAW
9: UPDATE
10: FAIL
A registry for CPNP errors should be created. The following codes
are reserved:
1: Message Validation Error
2: Authentication Required
3: Authorization Failed
4: Administratively prohibited
5: Out of Resources
6: Network Presence Error
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7: More Time Rejected
15. Acknowledgements
Thanks to Diego R. Lopez for his comments.
16. References
16.1. Normative References
[RFC1123] Braden, R., Ed., "Requirements for Internet Hosts -
Application and Support", STD 3, RFC 1123,
DOI 10.17487/RFC1123, October 1989,
<http://www.rfc-editor.org/info/rfc1123>.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<http://www.rfc-editor.org/info/rfc2119>.
[RFC4086] Eastlake 3rd, D., Schiller, J., and S. Crocker,
"Randomness Requirements for Security", BCP 106, RFC 4086,
DOI 10.17487/RFC4086, June 2005,
<http://www.rfc-editor.org/info/rfc4086>.
[RFC5511] Farrel, A., "Routing Backus-Naur Form (RBNF): A Syntax
Used to Form Encoding Rules in Various Routing Protocol
Specifications", RFC 5511, DOI 10.17487/RFC5511, April
2009, <http://www.rfc-editor.org/info/rfc5511>.
16.2. Informative References
[ETICS] EU FP7 ETICS Project, "Economics and Technologies of
Inter-Carrier Services", January 2014, <https://www.ict-
etics.eu/fileadmin/documents/news/
ETICS_white_paper_final.pdf>.
[RFC2782] Gulbrandsen, A., Vixie, P., and L. Esibov, "A DNS RR for
specifying the location of services (DNS SRV)", RFC 2782,
DOI 10.17487/RFC2782, February 2000,
<http://www.rfc-editor.org/info/rfc2782>.
[RFC4026] Andersson, L. and T. Madsen, "Provider Provisioned Virtual
Private Network (VPN) Terminology", RFC 4026,
DOI 10.17487/RFC4026, March 2005,
<http://www.rfc-editor.org/info/rfc4026>.
Boucadair, et al. Expires March 19, 2016 [Page 48]
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[RFC4176] El Mghazli, Y., Ed., Nadeau, T., Boucadair, M., Chan, K.,
and A. Gonguet, "Framework for Layer 3 Virtual Private
Networks (L3VPN) Operations and Management", RFC 4176,
DOI 10.17487/RFC4176, October 2005,
<http://www.rfc-editor.org/info/rfc4176>.
[RFC6347] Rescorla, E. and N. Modadugu, "Datagram Transport Layer
Security Version 1.2", RFC 6347, DOI 10.17487/RFC6347,
January 2012, <http://www.rfc-editor.org/info/rfc6347>.
[RFC6462] Cooper, A., "Report from the Internet Privacy Workshop",
RFC 6462, DOI 10.17487/RFC6462, January 2012,
<http://www.rfc-editor.org/info/rfc6462>.
[RFC6574] Tschofenig, H. and J. Arkko, "Report from the Smart Object
Workshop", RFC 6574, DOI 10.17487/RFC6574, April 2012,
<http://www.rfc-editor.org/info/rfc6574>.
[RFC6770] Bertrand, G., Ed., Stephan, E., Burbridge, T., Eardley,
P., Ma, K., and G. Watson, "Use Cases for Content Delivery
Network Interconnection", RFC 6770, DOI 10.17487/RFC6770,
November 2012, <http://www.rfc-editor.org/info/rfc6770>.
[RFC6793] Vohra, Q. and E. Chen, "BGP Support for Four-Octet
Autonomous System (AS) Number Space", RFC 6793,
DOI 10.17487/RFC6793, December 2012,
<http://www.rfc-editor.org/info/rfc6793>.
[RFC6830] Farinacci, D., Fuller, V., Meyer, D., and D. Lewis, "The
Locator/ID Separation Protocol (LISP)", RFC 6830,
DOI 10.17487/RFC6830, January 2013,
<http://www.rfc-editor.org/info/rfc6830>.
[RFC6973] Cooper, A., Tschofenig, H., Aboba, B., Peterson, J.,
Morris, J., Hansen, M., and R. Smith, "Privacy
Considerations for Internet Protocols", RFC 6973,
DOI 10.17487/RFC6973, July 2013,
<http://www.rfc-editor.org/info/rfc6973>.
[RFC7149] Boucadair, M. and C. Jacquenet, "Software-Defined
Networking: A Perspective from within a Service Provider
Environment", RFC 7149, DOI 10.17487/RFC7149, March 2014,
<http://www.rfc-editor.org/info/rfc7149>.
[RFC7297] Boucadair, M., Jacquenet, C., and N. Wang, "IP
Connectivity Provisioning Profile (CPP)", RFC 7297,
DOI 10.17487/RFC7297, July 2014,
<http://www.rfc-editor.org/info/rfc7297>.
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Authors' Addresses
Mohamed Boucadair
France Telecom
Rennes 35000
France
Email: mohamed.boucadair@orange.com
Christian Jacquenet
France Telecom
Rennes 35000
France
Email: christian.jacquenet@orange.com
Dacheng Zhang
Huawei Technologies
Email: zhangdacheng@huawei.com
Panos Georgatsos
Centre for Research and Innovation Hellas
78, Filikis Etairias str.
Volos, Hellas 38334
Greece
Phone: +302421306070
Email: pgeorgat@iti.gr
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