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Versions: (draft-watson-cdni-use-cases) 00 01 02 03 04 05 06 07 08 09 10 RFC 6770

Internet Engineering Task Force                         G. Bertrand, Ed.
Internet-Draft                                                E. Stephan
Intended status: Informational                   France Telecom - Orange
Expires: March 25, 2012                                        G. Watson
                                                            T. Burbridge
                                                              P. Eardley
                                                                      BT
                                                                   K. Ma
                                                           Azuki Systems
                                                      September 22, 2011


         Use Cases for Content Delivery Network Interconnection
                      draft-ietf-cdni-use-cases-00

Abstract

   Content Delivery Networks (CDNs) are commonly used for improving the
   footprint and the end-user experience of a content delivery service,
   at a reasonable cost.  This document outlines real world use-cases
   (not technical solutions) for interconnecting CDNs.  It can be used
   to provide guidance to the CDNI WG about the interconnection
   arrangements to be supported and to validate the requirements of the
   various CDNI interfaces.

   This document describes a number of use cases that motivate CDN
   Interconnection.  It represents a work in progress and may be
   extended later to cover additional use-cases.

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 http://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 March 25, 2012.

Copyright Notice




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   Copyright (c) 2011 IETF Trust and the persons identified as the
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   it for publication as an RFC or to translate it into languages other
   than English.



























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Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  4
     1.1.  Terminology  . . . . . . . . . . . . . . . . . . . . . . .  4
     1.2.  Abbreviations  . . . . . . . . . . . . . . . . . . . . . .  5
     1.3.  Rationale for Multi-CDN Systems  . . . . . . . . . . . . .  5
     1.4.  The Need for CDNI Standards  . . . . . . . . . . . . . . .  7
   2.  Footprint Extension Use Cases  . . . . . . . . . . . . . . . .  7
     2.1.  Geographic Extension . . . . . . . . . . . . . . . . . . .  7
     2.2.  Inter-Affiliates Interconnection . . . . . . . . . . . . .  8
     2.3.  Nomadic Users  . . . . . . . . . . . . . . . . . . . . . .  8
   3.  Offload Use Cases  . . . . . . . . . . . . . . . . . . . . . .  8
     3.1.  Overload Handling and Dimensioning . . . . . . . . . . . .  8
     3.2.  Resiliency . . . . . . . . . . . . . . . . . . . . . . . .  9
       3.2.1.  Failure of Content Delivery Resources  . . . . . . . .  9
       3.2.2.  Failure of Content Acquisition . . . . . . . . . . . .  9
   4.  CDN Capability Use Cases . . . . . . . . . . . . . . . . . . .  9
     4.1.  Device and Network Technology Extension  . . . . . . . . . 10
     4.2.  Technology and Vendor Interoperability . . . . . . . . . . 10
     4.3.  QoE and QoS Improvement  . . . . . . . . . . . . . . . . . 11
   5.  Policy Enforcement . . . . . . . . . . . . . . . . . . . . . . 11
     5.1.  Content Availability . . . . . . . . . . . . . . . . . . . 11
       5.1.1.  Geo-location Restrictions  . . . . . . . . . . . . . . 11
       5.1.2.  Temporal Restrictions  . . . . . . . . . . . . . . . . 12
       5.1.3.  Content Encoding Restrictions  . . . . . . . . . . . . 12
     5.2.  Branding . . . . . . . . . . . . . . . . . . . . . . . . . 13
     5.3.  Secure Access  . . . . . . . . . . . . . . . . . . . . . . 13
   6.  Open issues  . . . . . . . . . . . . . . . . . . . . . . . . . 13
   7.  Contributors . . . . . . . . . . . . . . . . . . . . . . . . . 13
   8.  Acknowledgments  . . . . . . . . . . . . . . . . . . . . . . . 14
   9.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 14
   10. Security Considerations  . . . . . . . . . . . . . . . . . . . 14
   11. References . . . . . . . . . . . . . . . . . . . . . . . . . . 15
     11.1. Normative References . . . . . . . . . . . . . . . . . . . 15
     11.2. Informative References . . . . . . . . . . . . . . . . . . 15
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 16















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1.  Introduction

   Content Delivery Networks (CDNs) are commonly used for improving the
   footprint and the end-user experience of a content delivery service,
   at a reasonable cost.  This document outlines real world use-cases
   (not technical solutions) for interconnecting CDNs.  It can be used
   to provide guidance to the CDNI WG about the interconnection
   arrangements to be supported and to validate the requirements of the
   various CDNI interfaces.

   This document describes a number of use cases that motivate CDN
   Interconnection.  It represents a work in progress and may be
   extended later to cover additional use-cases.

   This document identifies the main motivations for a CDN Provider to
   interconnect its CDN:

   o  CDN Footprint Extension Use Cases (Section 2)

   o  CDN Offload Use Cases (Section 3)

   o  CDN Capability Use Cases (Section 4)

   Then, the document highlights the need for interoperability to
   exchange and enforce content delivery policies (Section 5).

1.1.  Terminology

   We adopt the terminology described in
   [I-D.ietf-cdni-problem-statement], [RFC3466], and [RFC3568], except
   for the terms defined below.

   Authoritative CDN (aCDN):

   A CDN provider contracted by the CSP for delivery of content by its
   CDN or by its downstream CDNs.

   Access CDN:

   A CDN that is connected to the end-user's access and has information
   about the end-user's profile and access capabilities.

   Delivering CDN:

   The CDN that delivers the requested content asset to the end-user.
   In particular, the delivering CDN can be an access CDN.

   [Ed.  Note: Definition of recursive and iterative request routing



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   should be added to [I-D.davie-cdni-framework].]

   CDN Interconnection:

   Relationship between two CDNs that enables a CDN to provide content
   delivery services on behalf of another CDN.  It relies on a set of
   interfaces over which two CDNs communicate in order to achieve the
   delivery of content to end-users by one CDN (the downstream CDN) on
   behalf of another CDN (the upstream CDN).

   CDN peering: A business relation between two CDN providers based on
   one or more CDN Interconnections.

1.2.  Abbreviations

   [Ed.  Note: List of abbreviations to be updated later]

   o  CSP: Content Service Provider

   o  dCDN: downstream CDN

   o  NSP: Network Service Provider

   o  QoE: Quality of Experience

   o  QoS: Quality of Service

   o  SLA: Service Level Agreement

   o  uCDN: upstream CDN

   o  UA: User Agent

   o  UE: User Equipment

   o  VoD: Video on Demand

   o  WiFi: Wireless Fidelity

1.3.  Rationale for Multi-CDN Systems

   Content Delivery Networks (CDNs) are used to deliver content because
   they can:

   o  improve the experience for the End User; for instance delivery has
      lower latency and better robustness,





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   o  reduce the operator's costs; for instance lower delivery cost
      (reduced bandwidth usage) for cacheable content,

   o  reduce the Content Service Provider costs, such as datacenter
      capacity, space, and electricity consumption.

   Indeed, many network service providers and enterprise service
   providers are deploying or have deployed their own CDNs.  Despite the
   potential benefits of interconnecting CDNs, today each CDN is a
   standalone network.  The objective of CDN interconnection is to
   overcome this restriction: the interconnected CDNs should be able to
   collectively behave as a single delivery infrastructure.

   Let's take an example, as depicted in Figure 1.  Two CDN Providers
   establish a CDN Interconnection.  The Content Service Provider CSP-1
   reaches an agreement with CDN Provider A for the delivery of its
   content.  CDN Provider A and CDN Provider B agree to interconnect
   their CDNs.  When a User Agent that is connected to CDN Provider B's
   network requests Content from CSP-1, the Content is actually
   delivered from CDN-B, because handling of requests for CSP-1's
   Content has been delegated as part of the CDN Interconnection
   agreement.  The End User benefits through a better quality of
   experience, because the Content is delivered from a nearby Surrogate.
   CDN Provider A benefits because it doesn't need to deploy such an
   extensive CDN, whilst CDN Provider B receives some compensation for
   the delivery.  CSP-1 benefits because it only needs to make one
   business agreement and one physical connection, with CDN Provider A,
   but its End Users get a service quality as though CSP-1 had also gone
   to the trouble of making a business agreement with CDN Provider B.


         +-------+              +-------+
         | CSP-1 |              | CSP-2 |
         +-------+              +-------+
             |                      |
        ,--,--,--.             ,--,--,--.
     ,-'          `-.       ,-'          `-.
    ( CDN Provider A )=====( CDN Provider B )
     `-.  (CDN-A) ,-'       `-. (CDN-B)  ,-'
        `--'--'--'             `--'--'--'
                                   |
                             +------------+
                             | User Agent |
                             +------------+
    === CDN Interconnection


                                 Figure 1



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   To extend the example, another Content Service Provider, CSP-3, may
   also reach an agreement with CDN Provider A. But it does not want its
   Content to be distributed by CDN Provider B, for example, CSP-3 may
   not have distribution rights in the country where CDN Provider B
   operates.  This example illustrates that policy considerations are an
   important part of CDNI.

1.4.  The Need for CDNI Standards

   Existing CDN interfaces are proprietary and have often been designed
   for intra-CDN/intra-domain operations.  So an external CDN typically
   cannot use them, especially if the two CDNs rely on different
   implementations.  Nevertheless, [I-D.bertrand-cdni-experiments] shows
   that some level of CDN interconnection can be achieved experimentally
   without standardized interfaces between the CDNs.  However, the
   methods used in these experiments are hardly usable in an operational
   context, because they suffer from several limitations in terms of
   functionalities, scalability, and security level.

   The aim of IETF CDNI WG's solution is therefore to overcome such
   shortcomings; a full list of requirements is being developed in
   [I-D.ietf-cdni-requirements].


2.  Footprint Extension Use Cases

   Footprint extension is expected to be a major use case for CDN
   interconnection.

2.1.  Geographic Extension

   In this use case, the CDN Provider wants to extend the geographic
   distribution that it can offer to its CSPs:

   o  without compromising the quality of delivery,

   o  without incurring additional transit and other network costs that
      would result from serving content from geographically or
      topologically remote surrogates.

   If there are several CDN Providers that have a geographically limited
   footprint (e.g., restricted to one country), or do not serve all end-
   users in a geographic area, then interconnecting their CDNs enables
   CDN Providers to provide their services beyond their own footprint.

   As an example, suppose a French CSP wants to distribute its TV
   programs to End Users located in France and various countries in
   North Africa.  It asks a French CDN Provider to deliver the content.



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   The French CDN Provider's network only covers France, so it makes an
   agreement with another CDN Provider that covers North Africa.
   Overall, from the CSP's perspective the French CDN Provider provides
   a CDN service for both France and North Africa.

   In addition to video, this use case applies to other types of content
   such as automatic software updates (browser updates, operating system
   patches, virus database update, etc).

2.2.  Inter-Affiliates Interconnection

   In the previous section, we have described the case of geographic
   extension between CDNs operated by different entities.  A large CDN
   Provider may also operate CDNs from several subsidiaries (which may
   rely on different CDN solutions, see Section 4.2).  In certain
   circumstances, the CDN Provider needs to make its CDNs interoperate
   to provide a consistent service to its customers on its whole
   footprint.

2.3.  Nomadic Users

   In this scenario a CSP wishes to allow users who move to other
   geographic regions to continue to access their content.  The
   motivation in this case is to allow nomadic users to maintain access
   with consistent quality of experience, rather than to allow all
   residents within a region access to the content.

   [Ed.  Note: expand on which CDNs need to be interconnected to address
   the use case (ie with CDN of "home NSP" interconnected to CDN of
   visited NSP).  Add a picture for clarifying the text.  Use the term
   "TV everywhere"?]

   This use case covers situations like users moving between different
   CDN Providers within the same geographic region, or users switching
   between different devices, as discussed in Section 4.


3.  Offload Use Cases

3.1.  Overload Handling and Dimensioning

   A CDN is likely to be dimensioned to support the prime-time traffic.
   However, unexpected spikes in content popularity may drive load
   beyond the expected peak.  The prime recurrent time peaks of content
   distribution may differ between two CDNs.  Taking advantage of the
   different traffic peak times, a CDN may interconnect with another CDN
   to increase its effective capacity during the peak of traffic.  This
   brings dimensioning savings to the CDNs as they can use the resources



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   of each other during their respective peaks of activity..

   Offload also applies to planned situations where a CDN Provider needs
   CDN capacities in a particular region during a short period of time.
   For example, a CDN can offload traffic to another CDN during a
   specific maintenance operation or for covering the distribution of a
   special event.  For instance, consider a TV-channel which has
   exclusive distribution rights on a major event, such as a
   celebrities' wedding, or a major sport competitions.  The CDNs that
   the TV-channel uses for delivering the content related to this event
   are likely to experience a flash crowd during the event and to need
   offloading traffic, while other CDNs will support a more usual
   traffic load and be able to handle the offloaded traffic load.

3.2.  Resiliency

3.2.1.  Failure of Content Delivery Resources

   It is important for CDNs to be able to guarantee service continuity
   during partial failures (e.g., failure of some Surrogates).  In
   partial failure scenarios, a CDN Provider could redirect some
   requests towards another CDN, which must be able to serve the
   redirected requests or, depending on traffic management policies, to
   forward these requests to the CSP's origin server.

3.2.2.  Failure of Content Acquisition

   Source content acquisition is typically handled in one of two ways:

   o  CDN origin, where a downstream CDN acquires content from an
      upstream CDN, and the authoritative CDN acquires content from an
      origin server of the CSP, or

   o  Other origin, where the CDNs acquire content directly from an
      origin server outside the uCDN.

   Resiliency may be required against failure to ingest content.  If a
   CDN is unable to retrieve the content, it may be that the CSP's
   origin server is inaccessible to only this CDN, in which case
   redirection of the end-users to an alternative CDN may circumvent the
   problem.  A CSP may also choose to specify one or more backup origin
   servers.


4.  CDN Capability Use Cases






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4.1.  Device and Network Technology Extension

   In this use case, the CDN Provider may have the right geographic
   footprint, but may wish to extend the supported range of devices and
   User Agents or the range of supported delivery technologies.  In this
   case, a CDN Provider may interconnect with a CDN that offers
   services:

   o  that its own CDN is not able to support or,

   o  that the CDN provider is not willing to provide.

   The following examples illustrate this use case:

   1.  CDN-A cannot support a specific delivery protocol.  For instance,
       CDN-A may interconnect with CDN-B to serve a proportion of its
       traffic that requires HTTPS.  CDN-A may use CDN-B's footprint
       (which may overlap with its own) to deliver HTTPS without needing
       to deploy its own infrastructure.  This case could also be true
       of other formats, delivery protocols (RTMP, RTSP, etc.) and
       features (specific forms of tokenization, per session encryption,
       etc.).

   2.  CDN-A has footprint covering traditional fixed line broadband and
       wants to extend coverage to mobile devices.  In this case, CDN-A
       may contract and interconnect with CDN-B who has both:

       *  physical footprint inside the mobile network,

       *  the ability to deliver content over a protocol that is
          required by specific mobile devices and not supported by
          CDN-A.

       In this case also it may be that CDN-B provides other features
       related to adapting the content.

   These cases can apply to many CDN features that a given CDN provider
   may not be able to support or not be willing to invest in, and thus,
   that the CDN provider would delegate to another CDN.

4.2.  Technology and Vendor Interoperability

   A CDN Provider may deploy a new CDN to run alongside its existing
   CDN, as a simple way of migrating its CDN service to a new
   technology.  A CDN Provider may have a multi-vendor strategy for its
   CDN deployment.  A CDN Provider may want to deploy a separate CDN for
   a particular CSP or a specific network.  In all these circumstances,
   CDNI benefits the CDN Provider, as it simplifies or automates some



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   inter-CDN operations (e.g., migrating the request routing function
   progressively).

4.3.  QoE and QoS Improvement

   Some CSPs are willing to pay a premium for enhanced delivery of
   Content to their End Users.  In some cases, even if the CDN Provider
   could deliver the content to the end users, it cannot meet the CSP's
   service level requirements.  So, it makes a CDN Interconnection
   agreement with another CDN Provider that can provide the expected
   quality of experience to the end-user, for instance an Access CDN
   able to deliver content from Surrogates located closer to the end-
   user.


5.  Policy Enforcement

   For the interconnection use cases described in previous sections, the
   delegation of content delivery may be dependent upon the ability to
   delegate delivery policy enforcement as well.  CSPs may rely on the
   ability to place delivery restriction on sets of content, which are
   provided by existing CDNs.  While the ability to support these
   features across interconnected CDNs is desirable, that may not always
   be feasible.  It is important to be able to detect or define when
   these features cannot be enforced.

5.1.  Content Availability

   The content distribution policies that a CSP attaches to a content
   asset depend on many criteria.  For instance, distribution policies
   for audiovisual content often combine:

   o  temporal constraints (e.g., available for 24 hours, available 28
      days after DVD release, etc.),

   o  resolution-based constraints (e.g., high definition vs. standard
      definition), and

   o  geolocation-based constraints (e.g., per country).

5.1.1.  Geo-location Restrictions

   "Geo-blocking" rules may specify:

   o  the geographic regions where content can be delivered from (i.e.
      the location of the Surrogates), or





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   o  geographic locations where content can be delivered to (i.e., the
      location of the End Users).

   If a default value of "geo-blocking rules not supported" is set, the
   CSP may wish to deny all access to the content, or blacklist specific
   dCDNs which lack support for these features.

5.1.2.  Temporal Restrictions

   Time-based rules may specify:

   o  an activation time (i.e., the time when the content should become
      available for delivery),

   o  a deactivation time (i.e., time after which the content should no
      longer be delivered), or

   o  an expiration time (i.e., the time at which the content files
      should be expunged from all CDN storage).

   If a default value of "time-based rules not supported" is set, the
   CSP may wish to deny all access to the content, or blacklist specific
   dCDNs which lack support for these features.

5.1.3.  Content Encoding Restrictions

   [Ed.  Note: Section to be removed? reworded?]

   Encoding-based rules may specify:

   o  a subset of encodings deliverable to specific devices,

   o  a subset of encodings deliverable though a specific NSP, or

   o  a subset of encodings deliverable to users based on a subscription
      or quality of service levels.

   [Ed.  Note: FLF The first bullet only makes sense if the solution
   supports transcoding/transrating, which I don't know if it will be
   supported in Initial scope.  The last bullet does not make sense to
   me as we do not want the CDNs to be aware of any user subscription
   levels (ie only CSP is aware of user subscription level)."]

   If a default value of "encoding-based rules not supported" is set,
   the CSP may wish to deny all access to the content, or blacklist
   specific dCDNs which lack support for these features.





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5.2.  Branding

   There are situations where one CDN Provider cannot or does not want
   to operate all the functions of a uCDN, e.g., a CDN exchange, which
   handles request routing (and possibly log retrieval) but delegates
   all content delivery to the surrogates of other dCDNs.  Preserving
   the branding of the CSP throughout delivery is often important to the
   CSP.  CSPs may desire to offer content services under their own name,
   even when the associated CDN service involves other CDSPs.  The CSP
   may request that the name of the CDSPs does not appear in the URLs
   and may wish to specify a specific brand related tag to appear in the
   URLs.  Similarly, in offload situations, the uCDN might want to offer
   CDN services under its own branding.

   If a default value of "branding rules not supported" is set, the CSP
   may wish to deny all access to the content, or blacklist specific
   dCDNs which lack support for these features.

5.3.  Secure Access

   Many protocols exist for delivering content to End Users.  CSPs may
   often wish to dictate a specific protocol or set of protocols which
   are acceptable for delivery of their content, especially in the case
   where content protection or user authentication is required (e.g.,
   must use HTTPS and not HTTP, or must use URL hashing, etc.).

   If a default value of "secure access rules not supported" is set, the
   CSP may wish to deny all access to the content, or blacklist specific
   dCDNs which lack support for these features.


6.  Open issues

   The section about nomadic users must be clarified

   The section about Content Encoding Restrictions requires a
   discussion: must the CDN enforce such restrictions?


7.  Contributors

   [Ed.  Note: long list of co-authors.  As per current practice, you
   would want to split that into "editors" and "contributors".]

   The following people have strongly contributed to this
   specification's content:





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8.  Acknowledgments

   The authors would like to thank Kent Leung, Francois Le Faucheur and
   Ben Niven-Jenkins for lively discussions, as well as for their
   reviews and comments on the mailing list.

   They also thank the contributors of the EU FP7 OCEAN and ETICS
   projects for valuable inputs.


9.  IANA Considerations

   This memo includes no request to IANA.


10.  Security Considerations

   CDN Interconnection, as described in this document, has a wide
   variety of security issues that should be considered.  The security
   issues fall into three general categories:

   o  CSP Trust: where the CSP may have negotiated service level
      agreements for delivery quality of service with the uCDN, and/or
      configured distribution policies (e.g., geo-restrictions,
      availability windows, or other licensing restrictions), which it
      assumes will be upheld by dCDNs to which the uCDN delegates
      requests.  Furthermore, billing and accounting information must be
      aggregated from dCDNs with which the CSP may have no direct
      business relationship.  These situations where trust is delegated
      must be handled in a secure fashion to ensure CSP confidence in
      the CDN interconnection.

   o  Client Transparency: where the client device or application which
      connects to the CDN must be able to interact with any dCDN using
      its existing security and DRM protocols (e.g., cookies,
      certificate-based authentication, custom DRM protocols, URL
      signing algorithms, etc.) in a transparent fashion.

   o  CDN Infrastructure Protection: where the dCDNs must be able to
      identify and validate delegated requests, in order to prevent
      unauthorized use of the network and to be able to properly bill
      for delivered content.  A dCDN may not wish to advertise that it
      has access to or is carrying content for the uCDN or CSP,
      especially if that information may be used to enhance denial of
      service attacks.  In general, CDNI interfaces and protocols should
      minimize overhead for dCDNs.

   This document focuses on the motivational use cases for CDN



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   Interconnection, and does not analyze these threats in detail.


11.  References

11.1.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119, March 1997.

11.2.  Informative References

   [I-D.bertrand-cdni-experiments]
              Bertrand, G., Faucheur, F., and L. Peterson, "Content
              Distribution Network Interconnection (CDNI) Experiments",
              draft-bertrand-cdni-experiments-01 (work in progress),
              August 2011.

   [I-D.davie-cdni-framework]
              Davie, B. and L. Peterson, "Framework for CDN
              Interconnection", draft-davie-cdni-framework-00 (work in
              progress), July 2011.

   [I-D.ietf-cdni-problem-statement]
              Niven-Jenkins, B., Faucheur, F., and N. Bitar, "Content
              Distribution Network Interconnection (CDNI) Problem
              Statement", draft-ietf-cdni-problem-statement-00 (work in
              progress), September 2011.

   [I-D.ietf-cdni-requirements]
              Leung, K. and Y. Lee, "Content Distribution Network
              Interconnection (CDNI) Requirements",
              draft-ietf-cdni-requirements-00 (work in progress),
              September 2011.

   [I-D.ma-cdni-publisher-use-cases]
              Nair, R. and K. Ma, "Content Distribution Network
              Interconnection (CDNI) Publisher Use",
              draft-ma-cdni-publisher-use-cases-00 (work in progress),
              March 2011.

   [I-D.watson-cdni-use-cases]
              Watson, G., "CDN Interconnect Use Cases",
              draft-watson-cdni-use-cases-00 (work in progress),
              January 2011.

   [RFC3466]  Day, M., Cain, B., Tomlinson, G., and P. Rzewski, "A Model
              for Content Internetworking (CDI)", RFC 3466,



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              February 2003.

   [RFC3568]  Barbir, A., Cain, B., Nair, R., and O. Spatscheck, "Known
              Content Network (CN) Request-Routing Mechanisms",
              RFC 3568, July 2003.


Authors' Addresses

   Gilles Bertrand (editor)
   France Telecom - Orange
   38-40 rue du General Leclerc
   Issy les Moulineaux,   92130
   FR

   Phone: +33 1 45 29 89 46
   Email: gilles.bertrand@orange.com


   Stephan Emile
   France Telecom - Orange
   2 avenue Pierre Marzin
   Lannion  F-22307
   France

   Email: emile.stephan@orange.com


   Grant Watson
   BT
   pp GDC 1 PP14, Orion Building, Adastral Park, Martlesham
   Ipswich,   IP5 3RE
   UK

   Email: grant.watson@bt.com


   Trevor Burbridge
   BT
   B54 Room 70, Adastral Park, Martlesham
   Ipswich,   IP5 3RE
   UK

   Email: trevor.burbridge@bt.com







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   Philip Eardley
   BT
   B54 Room 77, Adastral Park, Martlesham
   Ipswich,   IP5 3RE
   UK

   Email: philip.eardley@bt.com


   Kevin Ma
   Azuki Systems
   43 Nagog Park
   Acton,   MA 01720
   USA

   Phone: +1 978 844 5100
   Email: kevin.ma@azukisystems.com


































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