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New draft: draft-day-cdnp-scenarios-03.txt



Please publish the following attached file as an Internet Draft:

Title: Content Internetworking Scenarios
Filename: draft-day-cdnp-scenarios-03.txt

Thanks.



Network Working Group                                             M. Day
Internet-Draft                                                     Cisco
Expires: September 2, 2001                                   D. Gilletti
                                                               CacheFlow
                                                              P. Rzewski
                                                                 Inktomi
                                                           March 2, 2001

                     Content Internetworking Scenarios
                      draft-day-cdnp-scenarios-03.txt

Status of this Memo

   This document is an Internet-Draft and is in full conformance with
   all provisions of Section 10 of RFC2026.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF), its areas, and its working groups. Note that
   other groups may also distribute working documents as Internet-
   Drafts.

   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."

   The list of current Internet-Drafts can be accessed at
   http://www.ietf.org/ietf/1id-abstracts.txt.

   The list of Internet-Draft Shadow Directories can be accessed at
   http://www.ietf.org/shadow.html.

   This Internet-Draft will expire on September 2, 2001.

Copyright Notice

   Copyright (C) The Internet Society (2001). All Rights Reserved.

Abstract
   This document sets forth several logical and detailed scenarios to
   be considered when evaluating systems and protocols for Content
   Internetworking.











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Table of Contents

   1.    Introduction................................................ 3
   2.    Logical Internetworking Interfaces.......................... 3
   2.1   Access Content Network...................................... 4
   2.2   Publishing Content Network.................................. 4
   2.3   Brokering Content Network................................... 4
   3.    Logical Internetworking Scenarios........................... 4
   3.1   Expanding Existing Content Network Footprint................ 5
   3.2   ACCOUNTING and REQUEST-ROUTING Across Multiple DISTIBUTING
         CONTENT NETWORKs............................................ 7
   3.3   ACCOUNTING PEERING Across Multiple DISTRIBUTING CONTENT
         NETWORKs.................................................... 9
   3.4   PUBLISHER peers w/multiple DISTRIBUTING CONTENT NETWORKs....10
   4.    Accounting..................................................11
   4.1   Key Assumptions.............................................12
   4.1.1 Content Has Value...........................................12
   4.1.2 Distribution Has Value......................................12
   4.2   Accounting Scenarios........................................13
   4.2.1 The Cable Scenario..........................................13
   4.2.2 The Telco Scenario..........................................13
   4.2.3 The Ticket Scenario.........................................14
   4.2.4 The Calling Card Scenario...................................14
   5.    Security Considerations.....................................14
   6.    Acknowledgements............................................14
         References..................................................14
         Authors' Addresses..........................................15
         Full Copyright Statement....................................15
























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1. Introduction

   This document presents several logical scenarios that are intended
   to describe potential Content Internetworking configurations. These
   logical scenarios describe how various entities may combine to
   provide a complete end-to-end solution. These scenarios answer two
   distinct needs:

   1.  To provide some concrete examples of what Content
       Internetworking is, and

   2.  To provide a basis for evaluating Content Internetworking
       proposals.

   Each of the logical internetworking scenarios gives an indication of
   how the various Content Internetworking systems can be combined.
   From [2] these systems are:

   1.  REQUEST-ROUTING PEERING SYSTEM

   2.  DISTRIBUTION PEERING SYSTEM

   3.  ACCOUNTING PEERING SYSTEM

   Some specific types of Content Networks are described whose
   internetworking interfaces may include only a subset of the
   functionality of the three systems.

   The internetworking scenarios presented in this document are also
   framed by the following concepts:

   1.  CONTENT Has Value

   2.  DISTRIBUTION Has Value

   3.  CLIENTS Have Value [Ed note: This is not expanded later. To be
       removed?]

   Scenarios that reference the above concepts are given within this
   document in an effort to describe some of the currently known
   business models. These descriptions are intended to provide
   guidelines for developing the requirements given in [3].

   Terms in ALL CAPS are defined in [1].

2. Logical Internetworking Interfaces

   A CDN is defined in [2] as having REQUEST-ROUTING, DISTRIBUTION, and
   ACCOUNTING interfaces. However, some participating networks may
   gravitate toward particular subsets of the Content Internetworking
   interfaces. Sample Content Networks that support these particular

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   subsets are described for easier reference in the further
   development of internetworking scenarios.

2.1  Access Content Network

   An Access Content Network (ACN) is a network that utilizes forward
   proxy caching as described in [2]. Because an ACN's CLIENTs are
   bound to a particular caching proxy in the ACN's network, REQUEST-
   ROUTING for these CLIENTs is statically defined by the ACN and is
   therefore out of the control of the ORIGIN.

   An ACN typically does not have direct relationships with PUBLISHERs.
   As a result, an ACN is likely to participate in "receive-only"
   DISTRIBUTION PEERING and ACCOUNTING PEERING.

   Also note that, because the caching proxies in a peered ACN are
   delivering content specifically on behalf of upstream ORIGINs, these
   caching proxies effectively become SURROGATEs in this context.

2.2  Publishing Content Network

   A Publishing Content Network (PCN) is an ORIGIN that has a
   NEGOTIATED RELATIONSHIP with several CONTENT NETWORKs. Because a PCN
   is the ORIGIN for a set of CONTENT, the PCN contains the A
   UTHORITATIVE REQUEST-ROUTING SYSTEM for that set of CONTENT.

   Because a PCN is the ORIGIN for a set of CONTENT, the PCN
   participates in "send-only" DISTRIBUTION PEERING (aka INJECTION),
   ACCOUNTING PEERING, and REQUEST-ROUTING PEERING.

2.3  Brokering Content Network

   A Brokering Content Network (BCN) is a network that does not operate
   its own surrogates or REQUEST-ROUTING systems. Instead, a BCN
   typically operates only CPGs as a service on behalf other Content
   Networks. A BCN may therefore be regarded as a "clearinghouse" for
   Content Internetworking information.

   For example, a BCN may choose to participate in DISTRIBUTION PEERING
   in order to aggregate CONTENT SIGNALs from several upstream sources
   into a single update stream for the benefit of downstream peers. A
   BCN may also choose to participate in ACCOUNTING PEERING in order to
   aggregate utilization data from several downstream networks into
   combined reports for upstream peers. Finally, a BCN may also choose
   to participate in REQUEST-ROUTING PEERING in order to aggregate
   REQUEST-ROUTING ADVERTISEMENTS from several sources into a single
   update stream for the benefit of other peers.

3. Logical Internetworking Scenarios

   This section provides several logical peering scenarios that may
   arise in Content Internetworking implementations.

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3.1 Expanding Existing Content Network Footprint

   This scenario considers the case where two or more existing CONTENT
   NETWORKs wish to peer and exchange content in order to provide an
   increased scale and reach for their existing customers. It assumes
   that all of these CONTENT NETWORKs already provide REQUEST-ROUTING,
   DISTRIBUTION, and ACCOUNTING services and that they will continue to
   provide these services to existing customers as well as offering
   them to their peers.

   In this scenario these CONTENT NETWORKs would be interconnected via
   a CONTENT PEERING GATEWAY which provides a REQUEST-ROUTING PEERING
   SYSTEM, a DISTRIBUTION PEERING SYSTEM, and an ACCOUNTING PEERING
   SYSTEM. The net result of this peering would be that a larger set of
   SURROGATES will now be available to the CLIENTs.

   FIGURE 1 shows three CONTENT NETWORKs which have peered to provide
   greater scale and reach to their existing customers. They are all
   participating in; DISTRIBUTION PEERING, REQUEST-ROUTING PEERING, and
   ACCOUNTING PEERING.

   As a result of these peering relationships it is assumed that:

   1.  CONTENT that has been INJECTed into any one of these CONTENT
       NETWORKs (ORIGIN CONTENT NETWORK) MAY be distributed into any
       peered DISTRIBUTING CONTENT NETWORK

   2.  Commands affecting the distribution of CONTENT MAY originate
       within the ORIGIN CONTENT NETWORK or MAY be issued within the
       DISTRIBUTING CONTENT NETWORK

   3.  Accounting information regarding CLIENT access and/or
       DISTRIBUTION actions will be made available to the ORIGIN
       CONTENT NETWORK by the DISTRIBUTING CONTENT NETWORK

   4.  The ORIGIN CONTENT NETWORK would provide this accounting
       information to the PUBLISHER based on existing Service Level
       Agreements (SLAs)

   5.  Requests by CLIENTS MAY be directed to SURROGATES within any of
       the peered CONTENT NETWORKs

   The decision of where to direct an individual CLIENT request MAY be
   dependent upon the DISTRIBUTION and REQUEST-ROUTING policies
   associated with the CONTENT being requested as well as the specific
   algorithms and methods used for directing these requests.

   It is also worthwhile to consider that any one of these peered
   CONTENT NETWORKs may also have other peering arrangements which may
   or may not be transitive to peering relationships created for the
   above purpose.

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               FIGURE 1 - Peering Existing CONTENT NETWORKs

   +--------------+                               +--------------+
   |     CN A     |                               |     CN B     |
   |..............|   +---------+   +---------+   |..............+
   | REQ-ROUTING  |<=>|         |<=>|         |<=>| REQ-ROUTING  |
   |..............|   | CONTENT |   | CONTENT |   |..............|
   | DISTRIBUTION |<=>| PEERING |<=>| PEERING |<=>| DISTRIBUTION |
   |..............|   | GATEWAY |   | GATEWAY |   |..............|
   |  ACCOUNTING  |<=>|         |<=>|         |<=>|  ACCOUNTING  |
   |--------------|   +---------+   +---------+   +--------------+
         | ^           \^ \^ \^       ^/ ^/ ^/           | ^
         v |            \\ \\ \\     // // //            v |
   +--------------+      \\ \\ \\   // // //      +--------------+
   |  SURROGATES  |       \\ v\ v\ /v /v //       |  SURROGATES  |
   +--------------+        \\+---------+//        +--------------+
          ^ |               v|         |v                ^ |
          | |                | CONTENT |                 | |
          | |                | PEERING |                 | |
          | |                | GATEWAY |                 | |
          | |                |         |                 | |
          | |                +---------+                 | |
          | |                  ^| ^| ^|                  | |
          | |                  || || ||                  | |
          | |                  |v |v |v                  | |
          | |              +--------------+              | |
          | |              |     CN C     |              | |
          | |              |..............|              | |
          | |              | REQ-ROUTING  |              | |
          | |              |..............|              | |
          \ \              | DISTRIBUTION |             / /
           \ \             |..............|            / /
            \ \            |  ACCOUNTING  |           / /
             \ \           |--------------|          / /
              \ \                | ^                / /
               \ \               v |               / /
                \ \        +--------------+       / /
                 \ \       |  SURROGATES  |      / /
                  \ \      +--------------+     / /
                   \ \           | ^           / /
                    \ \          | |          / /
                     \ \         v |         / /
                      \ \    +---------+    / /
                       \ \-->| CLIENTS |---/ /
                        \----|         |<---/
                             +---------+

NOTE:

   The above FIGURE 1 does not illustrate the CLIENT REQUEST path. It
   is assumed that the direction of CLIENT requests follows the

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   methodology given in [2] and that the end result is that the peered
   REQUEST-ROUTING SYSTEMs return the IP address of the SURROGATE
   deemed appropriate to honor the CLIENT's REQUEST.

3.2 ACCOUNTING and REQUEST-ROUTING Across Multiple DISTIBUTING CONTENT
    NETWORKs

   This scenario describes the case where a single entity (ORG A)
   performs ACCOUNTING and REQUEST-ROUTING functions but has no
   inherent DISTRIBUTION capabilities. This entity must therefore peer
   with one or more DISTRIBUTING CONTENT NETWORKs in order to provide a
   complete solution. A potential configuration which illustrates this
   concept is given in FIGURE 2.

   In the scenario shown in FIGURE 2, ORG A is responsible for
   collecting ACCOUNTING information from multiple CONTENT NETWORKs (CN
   A, and CN B) and providing a "clearing house"/reconciliation
   function as well as providing a REQUEST-ROUTING service across the
   peered CONTENT NETWORKs.

   In this scenario, CONTENT is injected into one of the peered CONTENT
   NETWORKs and its DISTRIBUTION between these peered CONTENT NETWORKs
   is controlled via the DISTRIBUTION PEERING SYSTEMs within the peered
   CPGs. The REQUEST-ROUTING system provided by ORG A is informed of
   the ability to serve a piece of CONTENT from a particular CONTENT
   NETWORK by the REQUEST-ROUTING SYSTEMs within the peered CPGs.

   ORG A collects statistics and usage information via the ACCOUNTING
   PEERING SYSTEM and disseminates that information to its peers as
   appropriate.

   As illustrated in FIGURE 2, there may be multiple REQUEST-ROUTING
   systems employed within the peered CONTENT NETWORKs. If the REQUEST-
   ROUTING SYSTEM provided by ORG A is the AUTHORITATIVE REQUEST-
   ROUTING SYSTEM for a given CONTENT DATA UNIT this is not a problem.
   However, the individual CDNs may also provide the AUTHORITATIVE
   DIRECTION SYSTEM for some portion of its existing customers. In this
   case care must be taken to ensure that the tree structure remains
   intact (i.e. there is one and only one REQUEST-ROUTING tree for a
   given CONTENT object).

   Also, it should be noted that FIGURE 2 does not illustrate the fact
   that ACCOUNTING PEERING and REQUEST-ROUTING PEERING MAY also exist
   between CN A and CN B.

   ORG A could also play an active role in managing the DISTRIBUTION.
   In this case an additional DISTRIBUTION PEERING relationships are
   required.





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     FIGURE 2 - Accounting and Request-Routing Across Multiple CONTENT
                                 NETWORKSs



       +--------------+
       |    ORG A     |
       |..............|     +-----------+
       | REQ-ROUTING  |<===>|           |
       |..............|     |  CONTENT  |
       |  ACCOUNTING  |<===>|  PEERING  |
       +--------------+     |  GATEWAY  |
                            |           |
                            +-----------+
                             ^| ^| ^| ^|
   +--------------+         // //   \\ \\         +--------------+
   |     CN A     |        |v |v     |v |v        |     CN B     |
   |..............|   +---------+   +---------+   |..............|
   | REQ-ROUTING  |<=>|         |   |         |<=>| REQ-ROUTING  |
   |..............|   | CONTENT |   | CONTENT |   |..............|
   | DISTRIBUTION |<=>| PEERING |<=>| PEERING |<=>| DISTRIBUTION |
   |..............|   | GATEWAY |   | GATEWAY |   |..............|
   |  ACCOUNTING  |<=>|         |   |         |<=>|  ACCOUNTING  |
   |--------------|   +---------+   +---------+   +--------------+
         | ^                                             | ^
         v |                                             v |
   +--------------+                               +--------------+
   |  SURROGATES  |                               |  SURROGATES  |
   +--------------+                               +--------------+
                ^ \                               ^ /
                 \ \                             / /
                  \ \                           / /
                   \ \                         / /
                    \ \      +---------+      / /
                     \ \---->| CLIENTS |-----/ /
                      \------|         |<-----/
                             +---------+


   As in the previous diagram (FIGURE 1), the communication path(s)
   between the CLIENT and the REQUEST-ROUTING SYSTEM have been omitted
   in order to better illustrate the peering connections. It should be
   noted that FIGURE 2 also omits the (optional) DISTRIBUTION PEERING
   connection which MAY be implemented between ORG A and any or all of
   the peered CONTENT NETWORKs.

   It is also worthwhile to consider that any one of these peered
   entities may also have other peering arrangements which may or may
   not be transitive to peering relationships created for the above
   purpose.


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3.3 ACCOUNTING PEERING Across Multiple DISTRIBUTING CONTENT NETWORKs

   This scenario describes the case where a single ACCOUNTING SYSTEM
   (ORG A) provides a settlement/clearing-house function and wishes to
   peer w/multiple DISTRIBUTING CDNs. For the purposes of this scenario
   it is not necessary to consider the specifics of REQUEST-ROUTING
   PEERING.

   In this scenario the entity which operates the ACCOUNTING SYSTEM
   would enter into ACCOUNTING PEERING relationships w/one or more
   DISTRIBUTING CDNs as shown in FIGURE 3.

   FIGURE 3 - Accounting Across Multiple CONTENT NETWORKs



       +--------------+
       |    ORG A     |
       |..............|     +-----------+
       |  ACCOUNTING  |<===>|           |
       +--------------+     |  CONTENT  |
                            |  PEERING  |
                            |  GATEWAY  |
                            |           |
                            +-----------+
                                ^| ^|
   +--------------+            //   \\            +--------------+
   |     CN A     |           |v     |v           |     CN B     |
   |..............|   +---------+   +---------+   |..............|
   | REQ-ROUTING  |<=>|         |<=>|         |<=>| REQ-ROUTING  |
   |..............|   | CONTENT |   | CONTENT |   |..............|
   | DISTRIBUTION |<=>| PEERING |<=>| PEERING |<=>| DISTRIBUTION |
   |..............|   | GATEWAY |   | GATEWAY |   |..............|
   |  ACCOUNTING  |<=>|         |   |         |<=>|  ACCOUNTING  |
   |--------------|   +---------+   +---------+   +--------------+
         | ^                                             | ^
         v |                                             v |
   +--------------+                               +--------------+
   |  SURROGATES  |                               |  SURROGATES  |
   +--------------+                               +--------------+
                ^ \                               ^ /
                 \ \                             / /
                  \ \                           / /
                   \ \                         / /
                    \ \      +---------+      / /
                     \ \---->| CLIENTS |-----/ /
                      \------|         |<-----/
                             +---------+

   In this scenario, the DISTRIBUTION of CONTENT and the direction of
   CLIENT REQUESTs are controlled via the DISTRIBUTION PEERING SYSTEMs
   and REQUEST-ROUTING PEERING SYSTEMs within the peered CPGs. These

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   systems MAY be decoupled from the ACCOUNTING or they may use
   information obtained via an optional ACCOUNTING PEERING relationship
   between CN A and CN B.

   As in the previous diagrams, the communication path(s) between the
   CLIENT and the REQUEST-ROUTING SYSTEM have been omitted in order to
   better illustrate the peering connections.

   It is also worthwhile to consider that any one of these peered
   entities may also have other peering arrangements which may or may
   not be transitive to peering relationships created for the above
   purpose.

3.4 PUBLISHER peers w/multiple DISTRIBUTING CONTENT NETWORKs

   This scenario, shown in FIGURE 4 describes the case where a
   PUBLISHER wishes to directly enter into peering relationships
   w/multiple DISTRIBUTING CONTENT NETWORKs.

   In this scenario the PUBLISHER would operate its own CPG and enter
   into; DISTRIBUTION PEERING, ACCOUNTING PEERING, and REQUEST-ROUTING
   peering with one or more DISTRIBUTING CONTENT NETWORKs.

   FIGURE 4 assumes that the PUBLISHER operates as the AUTHORITATIVE
   REQUEST-ROUTING SYSTEM for its CONTENT although it is possible that
   this function may be designated to one of the DISTRIBUTING CONTENT
   NETWORKs. If this delegation occurs then it is not necessary for the
   PUBLISHER to have a REQUEST-ROUTING PEERING relationship to the
   DISTRIBUTING CONTENT NETWORKs.

   It likely that a PUBLISHER may also wish to use a third party to
   perform ACCOUNTING and BILLING. In that case there is no need for an
   ACCOUNTING PEERING relationship between the PUBLISHER's CPG and
   those of the DISTRIBUTING CONTENT NETWORKs.

   Likewise, it is possible that the PUBLISHER may only be interested
   in obtaining additional control over the DISTRIBUTION of its
   CONTENT. In that case, the only peering relationship that would be
   required between the PUBLISHER's CPG and those of the DISTRIBUTING
   CONTENT NETWORKs would be a DISTRIBUTION PEERING relationship.

   As in the previous diagrams, the communication path(s) between the
   CLIENT and the REQUEST-ROUTING SYSTEM have been omitted in order to
   better illustrate the peering connections.

   It is also worthwhile to consider that any one of these peered
   entities may also have other peering arrangements which may or may
   not be transitive to peering relationships created for the above
   purpose.




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   FIGURE 4 - PUBLISHER Peers w/Multiple DISTRIBUTING CONTENT NETWORKs



   +--------------+
   |  PUBLISHER   |
   |..............|   +-----------+
   | REQ-ROUTING  |<=>|           |<---\
   |..............|   |  CONTENT  |----\\
   | DISTRIBUTION |<=>|  PEERING  |     \\
   |..............|   |  GATEWAY  |--\   \\
   |  ACCOUNTING  |<=>|           |<-\\   \\
   +--------------+   +-----------+   \\   \\
                        ^| ^| ^|  ^|   \\   ||
   +--------------+     || || ||   \\   ||  ||    +--------------+
   |     CN A     |     |v |v |v    \v  |v  |v    |     CN B     |
   |..............|   +---------+   +---------+   |..............|
   | REQ-ROUTING  |<=>|         |   |         |<=>| REQ-ROUTING  |
   |..............|   | CONTENT |   | CONTENT |   |..............|
   | DISTRIBUTION |<=>| PEERING |   | PEERING |<=>| DISTRIBUTION |
   |..............|   | GATEWAY |   | GATEWAY |   |..............|
   |  ACCOUNTING  |<=>|         |   |         |<=>|  ACCOUNTING  |
   |--------------|   +---------+   +---------+   +--------------+
         | ^                                             | ^
         v |                                             v |
   +--------------+                               +--------------+
   |  SURROGATES  |                               |  SURROGATES  |
   +--------------+                               +--------------+
                ^ \                               ^ /
                 \ \                             / /
                  \ \                           / /
                   \ \                         / /
                    \ \      +---------+      / /
                     \ \---->| CLIENTS |-----/ /
                      \------|         |<-----/
                             +---------+

4. Accounting

   There are several concepts that are helpful to consider when
   attempting to model the various accounting scenarios that can be
   realized when peering CONTENT NETWORKs. The most fundamental of
   these is the assignment of value within the distribution exchange.

   In any distribution system, revenue will generally flow in the
   direction of value. In order to insure that this revenue flows
   accurately, it is necessary to provide accurate statistical and
   access related information to one or more BILLING or ACCOUNTING
   organizations. In general it can be assumed that accounting
   information originates within the DISTRIBUTING CONTENT NETWORKs and
   flows towards the BILLING/ACCOUNTING organizations. However it is
   entirely appropriate to consider that this data may flow through one

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   or more aggregation points. In fact the ability to aggregate
   statistical and access related information is essential to allow for
   scalability within the proposed solution.

   It should be noted that value exists at many points in a peered
   DISTRIBUTION system. To fully consider this problem one should
   assume that, in general, any element of the DISTRIBUTION system
   could have an assigned value associated with its use. This raises
   some obvious questions about settlement that are outside the scope
   of this document. A more detailed description of these requirements
   is contained within [3]. For the purposes of this effort it is
   sufficient to insure that the appropriate accounting data is capable
   of being transferred from the measurement point to the
   BILLING/ACCOUNTING system.

4.1 Key Assumptions

   The distribution of accounting information, like the distribution of
   content, is greatly affected by the following concepts.

4.1.1 Content Has Value

   This concept assumes that the content has intrinsic value and that
   the revenue (and ACCOUNTING information) flows from the consumer to
   the PUBLISHER. A consumer, as defined in this relationship, is the
   entity that consumes data. Therefore the consumer may be a CLIENT or
   a SURROGATE.

   An example of this concept would include services such as Video On
   Demand (VOD).

4.1.2 Distribution Has Value

   This concept describes the situation where the value is located
   within the CONTENT NETWORK service being provided. In this case the
   revenue as well as the statistical and access information flow
   toward the CONTENT NETWORK that provides the service. (NOTE: There
   may be other ACCOUNTING flows in addition to the one described.)

   When considering this case, it is a reasonable assumption to
   consider that the majority of the statistical and access information
   would be produced and consumed within a single CONTENT NETWORK's
   domain and is therefore not important to consider. However, it is
   not reasonable to assume that all such information is obtained in
   this manner. The latter is especially true when a third-party
   BILLING ORGANIZATION or complex peering arrangements are in place.

   An example of this case is where a service provider has an
   aggregated CLIENT population which is of sufficient interest to one
   or more PUBLISHERs. In this case the PUBLISHERs are willing to pay
   to access the CLIENTs of the service provider and revenue flows from
   the PUBLISHER to the service provider.

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4.2 Accounting Scenarios

   There are four basic conceptual accounting scenarios that SHOULD be
   considered when describing the requirements for the peering of
   accounting events between peered distribution entities:[Editor's
   Note: Other models suitable for real-time provisioning may be added
   to this proposal over time.]

   o  Flat Rate Accounting Scenario - (aka "The Cable Scenario)

   o  Metered Accounting Scenario - (aka "The Telco Scenario")

   o  Prepay Event Accounting Scenario - (aka "The Ticket Scenario")

   o  Prepay Metered Accounting Scenario - (aka "The Calling Card
      Scenario")

   These scenarios are described in the following sections.

4.2.1 The Cable Scenario

   In this scenario there is a "subscription" fee associated with the
   reception of CONTENT. In its primary mode it consists of a CLIENT
   entering into a transaction, either directly with the PUBLISHER or
   through some third party, for the purposes of obtaining access to
   one or more CONTENT objects. Once the transaction has been approved
   the CLIENT receives an entitlement to access the requested CONTENT
   for the duration of the subscription interval.

   An extension to this scenario is the case where a given DISTRIBUTING
   CONTENT NETWORK enters into a redistribution agreement with a
   PUBLISHER. In this scenario, the scope of the transaction is between
   the PUBLISHER and the specific DISTRIBUTION CONTENT NETWORK. Once
   the transaction is successful, the DISTRIBUTION CONTENT NETWORK
   obtains the right to redistribute that content in some mutually
   agreed upon manner. The manner of redistribution can range from
   unlimited to highly restricted.

   The resultant accounting information for this scenario consists of a
   single transaction which is associated with a specific consumer or
   CLIENT.

4.2.2 The Telco Scenario

   This scenario associates a finite value with the access or
   consumption of one or more CONTENT objects and attempts to fully
   control and/or account for access to this CONTENT.

   The resultant accounting information for this scenario is a set of
   detailed or summary accounting records associated with a specific
   CLIENT.

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4.2.3 The Ticket Scenario

   In this scenario the CLIENT obtains a ticket (or entitlement) in
   advance of accessing the CONTENT. This is accomplished by a
   transaction between the CLIENT and the PUBLISHER or their agent(s).
   The ticket is assumed to be a one-time entitlement which expires
   upon use.

4.2.4 The Calling Card Scenario

   In this scenario a CLIENT prepays and receives an entitlement to
   access a set of CONTENT objects up to some pre-specified value
   level. The total value of the entitlement is determined at the time
   of purchase and its value is decremented each time the CLIENT
   accesses the CONTENT or CONTENT NETWORK service. The amount of the
   decrement will be specific to the CONTENT or CONTENT NETWORK service
   being accessed. The CLIENT is able to continue accessing or
   consuming the CONTENT or CONTENT NETWORK service until the
   entitlement is fully depleted.

5. Security Considerations

   This document describes scenarios for use in evaluating Content
   Internetworking proposals. As such, it does not propose any
   solutions which might have security concerns.

   This document assumes that any peering solutions which are derived
   within CDI will be compliant with the trust model given in [4].

6. Acknowledgements

   The authors acknowledge the contributions and comments of Fred
   Douglis (AT&T), Raj Nair (Cisco), Gary Tomlinson (CacheFlow), John
   Scharber (CacheFlow), and Nalin Mistry (Nortel).

References

   [1]  Day, M., Cain, B., Tomlinson, G., and P. Rzewski, "A Model for
        Content Internetworking", draft-day-cdnp-model-05.txt (work in
        progress), March 2001,
        <URL:http://www.ietf.org/internet-drafts/draft-day-cdnp-model-
        02.txt>.

   [2]  Green, M., Cain, B., Tomlinson, G., Thomas, S., and P. Rzewski,
        "Content Internetworking Architectural Overview", draft-green-
        cdnp-gen-arch-03.txt (work in progress), March 2001,
        <URL:http://www.ietf.org/internet-drafts/draft-green-cdnp-gen-
        arch-03.txt>.

   [3]  Gilletti, D., Nair, R., Scharber, J., and J. Guha, "CDN-I
        Internetworking Authentication, Authorization, and Accounting

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        Requirements", draft-gilletti-cdnp-aaa-reqs-01.txt (work in
        progress), March 2001,
        <URL:http://www.ietf.org/internet-drafts/draft-gilletti-cdnp-
        aaa-reqs-01.txt>.

   [4]  Aboba, B., Arkko, J. and D. Harrington, "Introduction to
        Accounting Management", RFC 2975, October 2000,
        <URL:ftp://ftp.isi.edu/in-notes/rfc2975.txt>.

Authors' Addresses

   Mark S. Day
   Cisco Systems
   135 Beaver Street
   Waltham, MA  02452
   US

   Phone: +1 781 663 8310
   EMail: markday@cisco.com


   Don Gilletti
   CacheFlow Inc.

   EMail: don@cacheflow.com


   Phil Rzewski
   Inktomi
   4100 East Third Avenue
   MS FC1-4
   Foster City, CA 94404
   US

   Phone +1 650 653 2487
   Email: philr@inktomi.com

Full Copyright Statement

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   followed, or as required to translate it into languages other than
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Acknowledgement

   Funding for the RFC editor function is currently provided by the
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--
Phil Rzewski - Senior Architect - Inktomi Corporation
650-653-2487 (office) - 650-303-3790 (cell) - 650-653-1848 (fax)