Network Working Group                                            A. Ryan
Internet-Draft                                          Disney Streaming
Updates: 8006, 8008 (if approved)                           B. Rosenblum
Intended status: Standards Track                                  Vecima
Expires: 4 September 2022                                      N. Sopher
                                                                   Qwilt
                                                            3 March 2022


            CDNI Capacity Capability Advertisment Extensions
            draft-ryan-cdni-capacity-insights-extensions-02

Abstract

   Open Caching architecture is a use case of Content Delivery Networks
   Interconnection (CDNI) in which the commercial Content Delivery
   Network (CDN) is the upstream CDN (uCDN) and the ISP caching layer
   serves as the downstream CDN (dCDN).  This document supplements to
   the CDNI Capability Objects defined in RFC 8008 the defined
   capability objects structure and interface for advertisments and
   managment of a downstream CDN capacity.

Status of This Memo

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

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

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

   This Internet-Draft will expire on 4 September 2022.

Copyright Notice

   Copyright (c) 2022 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

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



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   and restrictions with respect to this document.  Code Components
   extracted from this document must include Revised BSD License text as
   described in Section 4.e of the Trust Legal Provisions and are
   provided without warranty as described in the Revised BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
     1.1.  Terminology . . . . . . . . . . . . . . . . . . . . . . .   3
     1.2.  Requirements Language . . . . . . . . . . . . . . . . . .   3
     1.3.  Objectives  . . . . . . . . . . . . . . . . . . . . . . .   4
   2.  CDNI Additonal Capability Objects . . . . . . . . . . . . . .   4
     2.1.  Telemetry Capability Object . . . . . . . . . . . . . . .   5
       2.1.1.  Telemetry Source Object . . . . . . . . . . . . . . .   6
         2.1.1.1.  Telemetry Source Types  . . . . . . . . . . . . .   7
         2.1.1.2.  Telemetry Source Metric Object  . . . . . . . . .   7
       2.1.2.  Telemetry Capability Object Serialization . . . . . .   8
     2.2.  CapacityLimits Capability Object  . . . . . . . . . . . .   9
       2.2.1.  Capacity Limit Object . . . . . . . . . . . . . . . .   9
         2.2.1.1.  Capacity Limit Types  . . . . . . . . . . . . . .  11
         2.2.1.2.  Capacity Limit Telemetry Source Object  . . . . .  11
         2.2.1.3.  Capacity Limit Scope Object . . . . . . . . . . .  12
       2.2.2.  Capacity Limit Object Serialization . . . . . . . . .  13
   3.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  14
     3.1.  CDNI Payload Types  . . . . . . . . . . . . . . . . . . .  14
       3.1.1.  CDNI FCI Telemetry Payload Type . . . . . . . . . . .  15
       3.1.2.  CDNI FCI Capacity Limits Payload Type . . . . . . . .  15
   4.  Security Considerations . . . . . . . . . . . . . . . . . . .  15
   5.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  15
   6.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  15
     6.1.  Normative References  . . . . . . . . . . . . . . . . . .  15
     6.2.  Informative References  . . . . . . . . . . . . . . . . .  16
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  17

1.  Introduction

   The Streaming Video Alliance [SVA] is a global association that works
   to solve streaming video challenges in an effort to improve end-user
   experience and adoption.  The Open Caching Working Group [OCWG] of
   the Streaming Video Alliance [SVA] is focused on the delegation of
   video delivery requests from commerical CDNs to a caching layer at
   the ISP's network.  Open Caching architecture is a specific use case
   of CDNI where the commercial CDN is the upstream CDN (uCDN) and the
   ISP caching layer is the downstream CDN (dCDN).  While delegating
   traffic from one CDN to the other, it is important to make sure that
   an appropriate amount of traffic is delegated.  In order to achive
   that, the SVA Open Caching Capacity Insight Specification [OC-CII]
   defines a feedback mechanism to inform the delegator how much traffic



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   is appropriate to delegate.  The traffic level information provided
   by that interface will be consumed by entities, such as the Open
   Caching Request router [OC-RR], to help inform that entity's traffic
   delegation decisions.  This document defines and registers CDNI
   Payload Types (as defined at section 7.1 of [RFC8006]).  These
   Payload types are used for Capability Objects added to those defined
   at section 4 of [RFC8008], which are required for the Open Caching
   Capacity Insights Interface [OC-CII].

   For consistency with other CDNI documents this document follows the
   CDNI convention of uCDN (upstream CDN) and dCDN (downstream CDN) to
   represent the commercial CDN and ISP caching layer respectively.

   This document registers two CDNI Payload Types (section 7.1 of
   [RFC8006]) for the defined capability objects:

   *  Telemetry Payload Type: A payload type for the capability object
      which defines supported telemetry sources, the metrics made
      available by that source, and corresponding configuration
      appropriate to the type of the source (host, port, protocol,
      etc..).

   *  CapacityLimits Payload Type: a payload type for the capability
      object which defines Capacity Limits based on a set of defined
      limit types and a mapping from those limits to corresponding
      telemetry sources for supporting real-time metrics.

1.1.  Terminology

   The following terms are used throughout this document:

   *  CDN - Content Delivery Network

   Additionally, this document reuses the terminology defined in
   [RFC6707], [RFC7336], [RFC8006], [RFC8007], [RFC8008], and [RFC8804].
   Specifically, we use the following CDNI acronyms:

   *  uCDN, dCDN - Upstream CDN and Downstream CDN respectively (see
      [RFC7336] )

1.2.  Requirements Language

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




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1.3.  Objectives

   In order to enable information exchange between a uCDN and a dCDN
   about acceptable levels of traffic to delegate, the following process
   has been defined:

   In normal operation a uCDN will communicate with a dCDN, via an
   interface, to collect and understand any limits that a dCDN has set
   forth for traffic delegation from a uCDN.  These limits will come in
   the form of metrics such as bits per second, requests per second,
   etc..  These limits can be thought of as Not to Exceed (NTE) limits.

   The dCDN should provide access to a telemetry source, of near real
   time metrics, that the uCDN can use to track current usage.  The uCDN
   should compare it's current usage to the limits the dCDN has put
   forth and adjust traffic delegation decisions accordingly to keep
   current usage under the specified limits.

   In summary, the dCDN will provide the uCDN of limits of how much
   traffic it should delegate towards the dCDN and then also provide a
   telemetry source that is coupled to the same scope as the limit, so
   that the uCDN can use to track its current usage against the
   advertised limit.  Having a limit and a corresponding telemetry
   source for that limit allows for a non ambiguous definition of what a
   particular limit means for both the uCDN and dCDN.

   Limits that are communicated from the dCDN to the uCDN should be
   considered valid based on the TTL of the response.  The TTL of the
   response will be provided by the transport mechanism for the response
   i.e. an HTTP Cache-Control header.  The intention is that the limits
   would have a long lived TTL and would represent a reasonable peak
   utilization limit that the uCDN should target.

   In the event that a dCDN needs to inform a uCDN of an update to a
   previously communicated limit, the dCDN SHOULD be able to leverage a
   uCDN callback endpoint to inform the uCDN of adjusted limits.  The
   most common use case for this would be related to dCDN infrastructure
   issues which reduced the amount of capacity previously advertised as
   being available.

2.  CDNI Additonal Capability Objects

   Section 5 of [RFC8008] describes the FCI Capability Advertisement
   Object, which contains a CDNI Capability Object as well as the
   capability object type (a CDNI Paylod Type).  The section also
   defines the Capability Objects per such type.  Below we define two
   additional Capability Objects.




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   Note: In the following sections, the term "mandatory-to-specify" is
   used to convey which properties MUST be included when serializing a
   given capability object.  When mandatory-to-specify is defined as
   "Yes" for an individual property, it means that if the object
   containing that property is included in an FCI message, then the
   mandatory-to-specify property MUST also be included.

2.1.  Telemetry Capability Object

   The Telemetry Capability Object is used to define a list of telemetry
   sources made available by the dCDN to the uCDN.  In this document,
   Telemetry data is being defined as near real time aggregated metics
   of dCDN utilization, such as bits per second egress, and should be
   specific to the uCDN and dCDN traffic delegation relationship.
   Telemetry data is uniqiely defined by a source id, a metrics name,
   along with the footprints that are associated with an FCI.Capability
   advertisement.  When defining a Capacity Limit, the meaning of a
   limit might be considered ambiguous if the uCDN and dCDN are defining
   current usage via different data sources.  Having the dCDN provide a
   data source defining usage that both itself and the uCDN reference,
   allows a non ambiguous metric to use when determing current usage and
   how that compares to a limit Telemetry data is not only an important
   component for making informed traffic delegation decisions but also
   for providing visiblity to traffic that has been delegated back
   through to upstream providers.  In situations where there are mutiple
   CDNi delegations, a uCDN will need to incorporate the usage
   information from any dCDN's it delegated to when itself is asked to
   provide usage information otherwise, the traffic may seem unaccounted
   for.  An example of this situation is when a Content Provider
   delegates traffic directly to a CDN, and that CDN decides to further
   delegate that traffic to a dCDN, if the Content Provider polls the
   uCDN for traffic usage, if the uCDN does not integrate the Telemetry
   data of the dCDN it delegated to, any of the traffic the uCDN
   delegated to it's dCDN would become invisible to the Content
   Provider.

      Property: sources

         Description: Telemetry sources made available to the uCDN.

         Type: A JSON array of Telemetry Source objects (see
         Section 2.1.1).

         Mandatory-to-Specify: Yes.







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2.1.1.  Telemetry Source Object

   The Telemetry Source Object is built of an associated type, a list of
   exposed metrics, and type-specific configuration data.

      Property: id

         Description: A unique identifier of a telemetry source.

         Type: String.

         Mandatory-to-Specify: Yes.

      Property: type

         Description: A valid telemetry source type.  See
         Section 2.1.1.1.

         Type: String.

         Mandatory-to-Specify: Yes.

      Property: metrics

         Description: The metrics exposed by this source.

         Type: A JSON array of Telemetry Source Metric objects (see
         Section 2.1.1.2).

         Mandatory-to-Specify: Yes.

      Property: configuration

         Description: a source-specific representation of the Telemetry
         source configuration.  For the generic source type, this
         configuration format is defined out-of-band.  For other types,
         the configuration format will be specified in a yet to be
         defined Telemetry Interface specification.  The goal of this
         element is to allow for forward compatability with a formal
         Telemetry interface.

         Type: A JSON object: TBD

         Mandatory-to-Specify: No.







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2.1.1.1.  Telemetry Source Types

   Below are the listed valid telemetry source types.  At the time of
   this draft, the type registry is limit to a single type of Generic.
   The intention of this type registry is to allow for future extension
   to reference a yet to be drafted specification for a CDNI Telemetry
   interface, which would standardize the definition, format,etc of
   Telemetry data between participants of a CDNI workflow.

          +=============+======================================+
          | Source Type | Description                          |
          +=============+======================================+
          | generic     | An object which allows for           |
          |             | advertisement of generic datasources |
          +-------------+--------------------------------------+

                                 Table 1

2.1.1.2.  Telemetry Source Metric Object

   The Telemetry Source Metric Object describe the metric to be exposed.

      Property: name

         Description: An identifier unique within this telemetry source.

         Type: String.

         Mandatory-to-Specify: Yes.

      Property: time-granularity

         Description: Represents the time frame that the data represents
         in seconds.  I.e. is this a data set over 5 minutes, one hour,
         etc..

         Type: Integer.

         Mandatory-to-Specify: No.

      Property: data-percentile

         Description: The percentile calculation the data represents,
         i.e. 50 percentile would equate to the median over the time-
         granularity.  Lack of a data-percentile will mean that the data
         is the average over the time representation.

         Type: Integer.



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         Mandatory-to-Specify: No.

      Property: latency

         Description: Time in seconds that the data is behind of real
         time.  This is important to specify to help the uCDN to
         understand how long it might take to reflect traffic
         adjustments in the metrics.

         Type: Integer.

         Mandatory-to-Specify: No.

2.1.2.  Telemetry Capability Object Serialization

   The following shows an example of Telemetry Capability including 2
   metrics for a source, that is scoped to a footprint.

   "capabilities": [
     {
       "capability-type": "FCI.Telemetry",
       "capability-value": {
         "sources": [
           {
             "id": "capacity_metrics_region1",
             "type": "generic",
             "metrics": [
               {
                 "name": "egress_5m",
                 "time-granularity": 300,
                 "data-percentile": 50,
                 "latency": 1500
               },
               {
                 "name": "requests_5m",
                  ...
               }
             ]
           }
         ]
       },
       "footprints": [
         <footprint objects>
       ]
     }
   ]





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2.2.  CapacityLimits Capability Object

   The Capacity Limits Capability Object enables the dCDN to specify
   traffic delegation limits to a uCDN within an FCI.Capabilities
   advertisement.  The limits specified by the dCDN will inform the uCDN
   on how much traffic can be delegated to the dCDN.  The limits
   specified by the dCDN should be considered Not To Exceed (NTE)
   limits.  The limits should be based on near real time telemetry data
   that the dCDN provides to the uCDN, or in other words, for each limit
   that is advertised, there should also exist a telemetry source which
   provides data of current utilization against the particular
   advertised limit.

      Property: limits

         Description: A collection of Capacity Limit objects.

         Type: A JSON array of CapacityLimit objects (see
         Section 2.2.1).

         Mandatory-to-Specify: Yes.

2.2.1.  Capacity Limit Object

   A CapacityLimit object is used to represent traffic limits for
   delegation from the uCDN towards the dCDN.  By default the limit
   object will be scoped to the footprint associated with the FCI
   capability advertisement encompassing this object.  The limit object
   can contain an optional scoping parameter which will allow
   specification of a limit for a subset of the encompassing footprint.
   Limits will be considered using a logical AND, such that a uCDN will
   need to ensure that all the limits are considered and honored rather
   than choosing the most specific only.  There SHOULD be at least one
   limit object without an optional scope per capability-value which
   will define the overall limit for the footprint.

      Property: scope

         Description: Defines an additional scope requirement for a
         limit within the FCI footprint context.  This CAN be specified
         if a dCDN would like to specify a more granular limit than what
         is currently possible via an FCI footprint alone.  An example
         of using the optional scope would be to specify a limit that
         should be applied to a specific published hostname within a
         particular FCI foorprint.  A limit object that does not contain
         this optional scope, should be considered to apply to the
         entire encompassing footprint associated with the capability
         advertisement



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         Type: Capacity Limit Scope object (see Section 2.2.1.3).

         Mandatory-to-Specify: No.

      Property: limit-type

         Description: The units of maximum-hard and maximum-soft.

         Type: String.  One of the values listed in Section 2.2.1.1.

         Mandatory-to-Specify: Yes.

      Property: id

         Description: Specifies a unique identifier associated with a
         limit.  The is CAN be used as a relational identifier to a
         specific Section 2.2.1.

         Type: String.

         Mandatory-to-Specify: No.

      Property: maximum-hard

         Description: The maximum unit of capacity that is available for
         use.

         Type: Integer.

         Mandatory-to-Specify: Yes.

      Property: maximum-soft

         Description: A soft limit at which an upstream should consider
         deducing traffic to prevent hitting the hard limit.

         Type: Integer.

         Mandatory-to-Specify: No.

      Property: current

         Description: Specifies the current usage value of the limit.
         It is not recommended to specify the current usage value inline
         with the FCI.CapacityLimits advertisements as it will reduce
         the ability to cache the response.  The intended method for
         providing telemetry data is to reference a Section 2.2.1.2 to
         poll for the current usage.



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         Type: Integer.

         Mandatory-to-Specify: No.

      Property: telemetry-source

         Description: Mapping of each a particular limit to a specific
         metric with relevant real-time data provided by a telemetry
         source.

         Type: Capacity Limit Telemetry Source object (see
         Section 2.2.1.2).

         Mandatory-to-Specify: No.

2.2.1.1.  Capacity Limit Types

   Below are listed the valid capacity limit types.  Additional limits
   would need to be specified and extended into this list.  The values
   specified here represent the types that were identified as being the
   most relevant metrics for the purposes of traffic delegation between
   CDNs.

                 +=================+=====================+
                 | Limit Type      | Units               |
                 +=================+=====================+
                 | egress          | Bits per second     |
                 +-----------------+---------------------+
                 | requests        | Requests per second |
                 +-----------------+---------------------+
                 | storage-size    | Total bytes         |
                 +-----------------+---------------------+
                 | storage-objects | Count               |
                 +-----------------+---------------------+
                 | sessions        | Count               |
                 +-----------------+---------------------+
                 | cache-size      | Total bytes         |
                 +-----------------+---------------------+

                                  Table 2

2.2.1.2.  Capacity Limit Telemetry Source Object

   The Capacity Limit Telemetry Source Object refers to a specific
   metric within a Telementry Source.

      Property: id




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         Description: Reference to the "id" of a telemetry source
         defined by a Telemetry Capability object.

         Type: String.

         Mandatory-to-Specify: Yes.

      Property: metric

         Description: Reference to the "name" property of a metric
         defined within a telemetry source of an FCI.Telemetry
         Capability object.

         Type: String.

         Mandatory-to-Specify: Yes.

2.2.1.3.  Capacity Limit Scope Object

   A CapacityLimitScope object is used to define a more granular scope
   for a limit within the encompassing footprint.  The object will
   define what type of scope is being declared (published host, service
   ids, etc..) and will then contain an array of items of the type
   defined (publishedhostA.cdn.com, publishedhostB.cdn.com,..).  The
   scope types are meant to be extendible and reference already
   established identifiers commonly used in delivery via a CDN.  The
   scope types MUST be mutually understood between the uCDN and dCDN.

      Property: type

         Description: Defines the type of scope definition.

         Type: String.  One of the values listed in Section 2.2.1.3.1.

         Mandatory-to-Specify: Yes.

      Property: values

         Description: A collection of values of Section 2.2.1.3.1.

         Type: A JSON array of strings of (see Section 2.2.1.3.1).

         Mandatory-to-Specify: Yes.








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2.2.1.3.1.  Capacity Limit Scope Types

   Below are listed the valid capacity limit types.  Additional limits
   would need to be specified and extended into this list.  The values
   specified here represent the types that were identified as being the
   most relevant metrics for the purposes of traffic delegation between
   CDNs.  The most recognized value will be the published-host, while
   the other values listed correspond to identifiers commonly used with
   commercial CDN providers that either reference a specific
   configuration or a logical grouping of configurations.

            +================+===============================+
            | Scope Type     | Description                   |
            +================+===============================+
            | published-host | CDN-Domain                    |
            +----------------+-------------------------------+
            | service-id     | an identifier associated with |
            |                | a group of configurations     |
            +----------------+-------------------------------+
            | property-id    | an identifier associated with |
            |                | a specific configuration      |
            +----------------+-------------------------------+

                                 Table 3

2.2.2.  Capacity Limit Object Serialization

   The following shows an example of an FCI.CapacityLimits object.

   "capabilities":[
     {
       "capability-type":"FCI.CapacityLimits",
       "capability-value":{
         "limits":[
           {
             "id":"capacity_limit_region1",
             "limit-type":"egress",
             "maximum-hard":50000000000,
             "maximum-soft":25000000000,
             "telemetry-source":{
               "id":"capacity_metrics_region1",
               "metric":"egress_5m"
             }
           },
           {
             "id":"capacity_limit_region1",
             "scope":{
               "type":"published-host",



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               "values":[
                 "serviceA.cdn.example.com"
               ]
             },
             "limit-type":"egress",
             "maximum-hard":20000000000,
             "maximum-soft":10000000000,
             "telemetry-source":{
               "id":"capacity_metrics_region1",
               "metric":"egress_service2_5m"
             }
           },
           {
             "scope":{
               "type":"service-id",
               "Values":[
                 "abcd4567ef9a"
               ]
             },
             "limit-type":"egress",
             "maximum-hard":30000000000,
             "maximum-soft":15000000000,
             "current":20000000000,
             "telemetry-source":{
               "id":"capacity_metrics_region3",
               "metric":"egress_service3_5m"
             }
           }
         ]
       },
       "footprints":[
         "<footprint objects>"
       ]
     }
   ]


3.  IANA Considerations

3.1.  CDNI Payload Types

   similar to the type definitions described in section 7.1 of [RFC8006]
   as well as the types described in section 6.1 of [RFC8008].

   This document requests the registration of the two additional payload
   types:





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                  +====================+===============+
                  | Payload Type       | Specification |
                  +====================+===============+
                  | FCI.Telemetry      | RFCthis       |
                  +--------------------+---------------+
                  | FCI.CapacityLimits | RFCthis       |
                  +--------------------+---------------+

                                 Table 4

   [RFC Editor: Please replace RFCthis with the published RFC number for
   this document.]

3.1.1.  CDNI FCI Telemetry Payload Type

      Purpose: The purpose of this Payload Type is to list the supported
      telemetry sources and the metrics made available by each source).

      Interface: FCI.

      Encoding: See section Section 2.1.

3.1.2.  CDNI FCI Capacity Limits Payload Type

      Purpose: The purpose of this Payload Type is to define Capacity
      Limits based on a utilization metrics corresponding to telemetry
      sources provided by the dCDN.

      Interface: FCI.

      Encoding: See section Section 2.2.

4.  Security Considerations

   This specification is in accordance with the CDNI Request Routing:
   Footprint and Capabilities Semantics.  As such, it is subject to the
   security and privacy considerations as defined in Section 8 of
   [RFC8006] and in Section 7 of [RFC8008] respectively.

5.  Acknowledgements

   The authors would like to express their gratitude to TBD for TBD
   (their guidance / contribution / reviews ...)

6.  References

6.1.  Normative References




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

   [RFC8006]  Niven-Jenkins, B., Murray, R., Caulfield, M., and K. Ma,
              "Content Delivery Network Interconnection (CDNI)
              Metadata", RFC 8006, DOI 10.17487/RFC8006, December 2016,
              <https://www.rfc-editor.org/info/rfc8006>.

   [RFC8007]  Murray, R. and B. Niven-Jenkins, "Content Delivery Network
              Interconnection (CDNI) Control Interface / Triggers",
              RFC 8007, DOI 10.17487/RFC8007, December 2016,
              <https://www.rfc-editor.org/info/rfc8007>.

   [RFC8008]  Seedorf, J., Peterson, J., Previdi, S., van Brandenburg,
              R., and K. Ma, "Content Delivery Network Interconnection
              (CDNI) Request Routing: Footprint and Capabilities
              Semantics", RFC 8008, DOI 10.17487/RFC8008, December 2016,
              <https://www.rfc-editor.org/info/rfc8008>.

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

   [RFC8804]  Finkelman, O. and S. Mishra, "Content Delivery Network
              Interconnection (CDNI) Request Routing Extensions",
              RFC 8804, DOI 10.17487/RFC8804, September 2020,
              <https://www.rfc-editor.org/info/rfc8804>.

6.2.  Informative References

   [OC-CII]   Ryan, A., Ed., Rosenblum, B., Goldstein, G., Roskin, R.,
              and G. Bichot, "Open Caching Capacity Insights -
              Functional Specification (Placeholder before
              publication)",
              <https://www.streamingvideoalliance.org/books/open-cache-
              capacity-insights-functional-specification/>.

   [OC-RR]    Finkelman, O., Ed., Hofmann, J., Klein, E., Mishra, S.,
              Ma, K., Sahar, D., and B. Zurat, "Open Caching Request
              Routing - Functional Specification", Version 1.1, 4
              October 2019,
              <https://www.streamingvideoalliance.org/books/open-cache-
              request-routing-functional-specification/>.

   [OCWG]     "Open Caching Home Page",
              <https://opencaching.streamingvideoalliance.org/>.



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   [RFC6707]  Niven-Jenkins, B., Le Faucheur, F., and N. Bitar, "Content
              Distribution Network Interconnection (CDNI) Problem
              Statement", RFC 6707, DOI 10.17487/RFC6707, September
              2012, <https://www.rfc-editor.org/info/rfc6707>.

   [RFC7336]  Peterson, L., Davie, B., and R. van Brandenburg, Ed.,
              "Framework for Content Distribution Network
              Interconnection (CDNI)", RFC 7336, DOI 10.17487/RFC7336,
              August 2014, <https://www.rfc-editor.org/info/rfc7336>.

   [SVA]      "Streaming Video Alliance Home Page",
              <https://www.streamingvideoalliance.org>.

Authors' Addresses

   Andrew Ryan
   Disney Streaming
   1211 Avenue of the Americas
   New York
               , NY 10036
   United States of America
   Email: andrew@andrewnryan.com


   Ben Rosenblum
   Vecima
   4375 River Green Pkwy #100
   Duluth
               , GA 30096
   United States of America
   Email: ben@rosenblum.dev


   Nir B. Sopher
   Qwilt
   6, Ha'harash
   Hod HaSharon
                4524079
   Israel
   Email: nir@apache.org











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