Internet DRAFT - draft-arolovitch-cdni-named-footprints
draft-arolovitch-cdni-named-footprints
Network Working Group A. Arolovitch
Internet-Draft Viasat
Updates: 7336, 8006, 8008 (if approved) 4 March 2024
Intended status: Standards Track
Expires: 5 September 2024
Content Delivery Network Interconnection (CDNI) Named Footprints
draft-arolovitch-cdni-named-footprints-01
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 extends the
Footprint & Capabilities Advertisement Interface (FCI) defined in
RFC8008, to allow advertising of named footprint objects, that can be
referenced in a consistent manner from Metadata Interface (MI), also
defined in RFC8006, as well as from the FCI itself as well as
additional interfaces in the Open Caching architecture. This
document also supplements the CDNI Metadata Footprint Types defined
in RFC8006 and modifies the CDNI operation as described in RFC7336.
Status of This Memo
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provisions of BCP 78 and BCP 79.
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This Internet-Draft will expire on 5 September 2024.
Copyright Notice
Copyright (c) 2024 IETF Trust and the persons identified as the
document authors. All rights reserved.
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This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents (https://trustee.ietf.org/
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Please review these documents carefully, as they describe your rights
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. What is a Footprint . . . . . . . . . . . . . . . . . . . 3
1.2. Types of footprint . . . . . . . . . . . . . . . . . . . 4
1.3. Footprint support in FCI today . . . . . . . . . . . . . 4
1.4. Motivations . . . . . . . . . . . . . . . . . . . . . . . 5
1.4.1. Interface-level footprint awareness . . . . . . . . . 5
1.4.2. Cross-interface consistency . . . . . . . . . . . . . 5
1.4.3. CDN slicing . . . . . . . . . . . . . . . . . . . . . 5
1.4.4. Management of complex footprints . . . . . . . . . . 5
1.4.5. Computational efficiency . . . . . . . . . . . . . . 6
1.5. Terminology . . . . . . . . . . . . . . . . . . . . . . . 6
2. Requirements . . . . . . . . . . . . . . . . . . . . . . . . 6
2.1. Footprints Advertisement . . . . . . . . . . . . . . . . 6
2.2. Hierarchy . . . . . . . . . . . . . . . . . . . . . . . . 7
2.3. Backwards compatibility . . . . . . . . . . . . . . . . . 7
2.4. Explicit Logic . . . . . . . . . . . . . . . . . . . . . 7
2.5. Consistent Datasource . . . . . . . . . . . . . . . . . . 8
2.6. Footprint Namespaces . . . . . . . . . . . . . . . . . . 9
2.7. Footprints and Service Identifiers . . . . . . . . . . . 9
3. Changes to CDNI Metadata . . . . . . . . . . . . . . . . . . 9
3.1. CDNI Metadata Additional Footprint Types . . . . . . . . 9
3.1.1. Expression Footprint Type . . . . . . . . . . . . . . 9
3.1.1.1. Expression Footprint Type Description . . . . . . 9
3.1.2. Named Footprint Type . . . . . . . . . . . . . . . . 10
3.1.2.1. Named Footprint Type Description . . . . . . . . 10
3.2. Changes to Existing CDNI Metadata Footprint Types . . . . 10
3.3. Changes to CDNI Metadata . . . . . . . . . . . . . . . . 11
3.3.1. MI NamedFootprint . . . . . . . . . . . . . . . . . . 11
3.3.2. MI NamedFootprintNamespace . . . . . . . . . . . . . 12
3.3.3. MI FootprintSource . . . . . . . . . . . . . . . . . 13
4. Changes to CDNI Operation . . . . . . . . . . . . . . . . . . 14
4.1. CDNI Operation Overview . . . . . . . . . . . . . . . . . 14
4.2. FCI Advertisement . . . . . . . . . . . . . . . . . . . . 15
4.3. Use of Named Footprints . . . . . . . . . . . . . . . . . 17
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 17
5.1. CDNI Metadata Footprint Types . . . . . . . . . . . . . . 17
6. Security Considerations . . . . . . . . . . . . . . . . . . . 17
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7. References . . . . . . . . . . . . . . . . . . . . . . . . . 17
7.1. Normative References . . . . . . . . . . . . . . . . . . 17
7.2. Informative References . . . . . . . . . . . . . . . . . 18
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 18
1. Introduction
The Streaming Video Technology Alliance [SVTA] 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 Technology Alliance
[SVTA] is focused on the delegation of video delivery requests from
commercial 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).
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.
1.1. What is a Footprint
The definition of footprint within existing CDNi and open caching
architecture literature remains ambiguous. Appendix B "Semantics for
Footprint Advertisement" of RFC8006 [RFC8006] reads:
Generally speaking, one can imagine two categories of footprints to
be advertised by a dCDN:
* A footprint could be defined based on coverage/reachability, where
"coverage/reachability" refers to a set of prefixes, a geographic
region, or similar boundary. The dCDN claims that it can cover/
reach "end user requests coming from this footprint".
* A footprint could be defined based on resources, where "resources"
refers to Surrogates a dCDN claims to have (e.g., the location of
Surrogates/resources). The dCDN claims that "from this footprint"
it can serve incoming end user requests.
Within the open caching architecture the use of footprints revolves
around uCDN handling an end user request. Therefore this document is
going to focus on the coverage footprints - a collection of end users
that dCDN is willing and able to serve, while leaving the room for
future use of footprints for management of dCDN cache resources. The
coverage footprint is defined through end user IP address (IPv4 and/
or IPv6 CIDRs), or attributes that can be derived from this address
(BGP autonomous system number, country code, subdivision code)
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1.2. Types of footprint
Several types of CDN footprints may be be defined:
* Disaggregated - CDN spanning disparate coverage regions, which lie
in different geographies and/or jurisdictions, yet share common
management.
* Regional - Different coverage regions within contiguous coverage,
that have distinct properties, yet users within one region may be
served from other CDN regions, for example in case of failure or
overload
* Functional - CDN regions with different functional and capacity
characteristics, e.g. highly distributed CDN with limited storage
capacity at each node
Furthermore, dCDN may manage different footprint break-down for
various traffic subsets it carries - by CDN tenant, type of traffic,
hostname, service identifier etc.
1.3. Footprint support in FCI today
The Footprint and Capabilities Interface (FCI), as specified in
[RFC8006] provides an interface, allowing uCDNs to query dCDN
capabilities, published via object-based data model in compliance
with [RFC8006] and [RFC8008]. The dCDN capabilities objects
published by FCI may optionally be associated with one or more
footprint, via the "footprints" property, which is an array of MI
Footprint objects.
The MI Footprint objects are encoded in compliance with [RFC8006] and
contain two properties: "footprint-type" and "footprint-value". They
are declarative and are scoped within their parent capability object.
The footprint types specified in [RFC8006] include IPv4 CIDR block
("ipv4cidr"), IPv6 CIDR block ("ipv6cidr"), BGP autonomous system
number ("asn") and country ("countrycode"). The footprint value
property is an array of one or more footprint values of the same
type.
According to [RFC8008], combination of multiple footprint types is to
be understood as additive or, in other words, as an implicit boolean
OR operation.
Neither [RFC8006] nor [RFC8008] provide instruction on how uCDN is to
match end user requests with higher-level footprint types like
country.
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1.4. Motivations
A need exists for dCDN to advertise footprints for use across
multiple dCDN interfaces in a way that is consistent, flexible and
can support complex footprint structure in a computationally
efficient way. Various motivations for having such capability
include:
1.4.1. Interface-level footprint awareness
By creating addressable footprints resources, it becomes possible for
all open caching interfaces to associate interface operations and
responses with specific footprints, including but not limited to: CDN
configuration by footprint, request routing methods by footprint,
cache management operations by footprint, logging by footprint,
capacity management and monitoring by footprint.
1.4.2. Cross-interface consistency
In several cases use of footprints may affect multiple interfaces.
For example, differentiated CDN configuration may trigger logging by
footprint or affect footprint-specific cache management operations.
In these cases common footprint definition that is external to
individual interfaces is required to assure consistency.
1.4.3. CDN slicing
In some cases, CDN providers may want to operate CDN footprints as
fully autonomous virtual CDNs, with their own configuration,
management and reporting as well as a distinct set of content
provider tenants. This capability is particularly useful for CDN
providers that manage disaggregated CDN footprints across different
geographies. In the CDN slicing scenario, the footprints may
optionally share some aspects of operation (i.e. have common
tenants), while differing in every other aspect, for operational
reasons. It is the duty of the uCDN to consistently use the
footprint across different interfaces, once advertised.
1.4.4. Management of complex footprints
Some types of footprints (e.g. distributed last-mile footprint) can
be highly dynamic and large in volume. Because of that they would
require high-frequency querying and benefit from caching support,
unlike capabilities advertisement which is relatively static in
nature. Because of this, it would be beneficial to allow querying of
individual footprint resources separately from capabilities
advertisement, which tends to be mostly static.
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1.4.5. Computational efficiency
Some of the uses of footprint advertisements are tied to uCDN request
handling, and should be as computationally efficient as possible.
1.5. Terminology
The following terms are used throughout this document:
* CDN - Content Delivery Network
* CIDR - Classless Internet-Domain Routing
Additionally, this document reuses the terminology defined in
[RFC7337], [RFC8006], and [RFC8008]. Specifically, we use the
following CDNI acronyms:
* uCDN, dCDN - Upstream CDN and Downstream CDN respectively (see
[RFC7336])
2. Requirements
2.1. Footprints Advertisement
dCDN must advertise its footprints via FCI as named resources,
separately from the capabilities advertised in the same interface.
dCDN is solely responsible for the footprints it advertises. This
footprint advertisement will provide a source of truth as to what
footprints are available from dCDN and be referenceable from FCI
capabilities and other open caching interfaces exposed by the same
dCDN.
uCDNs must authenticate themselves when accessing the footprint
advertising, subject to open caching authentication and authorization
framework. dCDN is at freedom to advertise different footprints to
different uCDN tenants. dCDN may change the content of footprint
advertisements, including publishing footprints without any footprint
values, however it is not at liberty to retire a footprint once
advertised as long as there are resources associated with it.
The footprints advertisement will provide mechanisms allowing uCDN to
manage a local cached copy of advertising, and differentiated
querying of individual, more dynamic footprints, while at the same
time allowing for the whole footprint advertisement to be captured.
The footprint advertising is to support both "coverage" and
"resource" footprints.
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2.2. Hierarchy
The dCDN advertisement must support explicit hierarchy, in which
footprints resources may include sub-footprints, e.g. specific
subdivision code within a country, list of IPv4 CIDRs within specific
ISP defined by one or more ASN etc. A footprint resource encompasses
all of the footprint values and sub-footprints within it, so
interface resources (e.g. logging, configuration hostnames, cache
management buckets) associated with a footprint apply to all of it,
including sub-footprints.
In case of conflict between interface resources of lower-level
footprint and higher-level footprint, the resources associated with
the lower-level footprint take priority. It is dCDN responsibility
to make sure that sub-footprints are indeed included in their parent
footprint scope. When matching an IP address against footprint
hierarchy, the lowest level footprint takes priority as well.
2.3. Backwards compatibility
The footprint definition must be backwards compatible with MI
Footprint encoding as specified in Section 4.2.2.2 of [RFC8006], as
well as all registered footprint types "CDNI Metadata Footprint
Types" sub-registry in the "Content Delivery Network Interconnection
(CDNI) Parameters". To enhance computability, consistency and
business logic of footprint advertisement, the specification may
introduce new footprint types as well as footprint properties, in
addition to footprint type and value.
2.4. Explicit Logic
In some cases, CDNs require complex footprints definitions, that
include inclusion and exclusion of specific footprint values from
footprint definitions (e.g. country code, exclusive of some ISPs and
that country but inclusive of some IPv4 or IPv6 CIDRs that are not
included in the current country definition). To support that,
footprint definitions to support Metadata Expression Language
exressions as defined in Section 3 of
[CDNI-Metadata-Model-Extensions]. The new footprint type "expr" is
to be introduced to the "CDNI Metadata Footprint Types" registry.
To accommodate footprint logic, the following MEL expression
variables are hereby introduced
* ep.asn - Endpoint AS number
* ep.ipv4addr - Endpoint IPv4 address
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* ep.ipv6addr - Endpoint IPv6 address
* ep.country - Endpoint country code
* ep.subdivision - Endpoint subdivision code
Thus, the following MEL expressions can be used for footprint
advertisement:
{
"footprint-type": "expr",
"footprint-value": [ " ( $ep.country == "us" ) and
not $ep.ipv4addr ipmatch ( "10.1.1/24" or "10.1.2.0/24" )" ]
}
{
"footprint-type": "expr",
"footprint-value": [ "( $ep.asn = 1234 ) or
( $ep.ipv4addr ipmatch "192.168.1/24" ) or
( $ep.ipv6addr ipmatch "2001:db8:3333:4444/48" )" ]
}
{
"footprint-type": "expr",
"footprint-value": [ "( $ep.country == "us" ) and
not ( $ep.subdivision=="us-ny" )" ]
}
2.5. Consistent Datasource
While IP-based footprint types like "ipv4cidr" and "ipv6cidr" are
unambiguous, when using other footprint types like "country" or
"asn", uCDN and dCDN need to use external databases to lookup the
footprint value using an IP address. Multiple databases for IP
address intelligence are in use in the industry today, which may be
at odds with each other over how to map particular IP address. Often
the ISP provider operating downstream CDN is the source of
authoritative mapping of IP addresses under its management. Thus
dCDN should be able to publish IP address mapping information in its
network for use by uCDN. When publishing footprint values that rely
on 3rd party datasources, dCDN should be able to indicate the origin
and specific version of datasource(s) used.
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2.6. Footprint Namespaces
dCDN may utilize different footprint break-down for different uCDN
traffic subsets it carries. There are multiple ways that dCDN may
identify such traffic, including hostname, type of traffic, service
identifiers etc. Additionally, there is a need to accommodate both
"resource" and "coverage" footprints.
To allow such differentiated break-down in an open way, footprint
namespaces are introduced, allowing dCDN to publish more than one
footprint break-down advertisement to each uCDN tenant. Matching of
IP address to footprint is unique within each namespace.
2.7. Footprints and Service Identifiers
Need exists to provide differentiated capabilities by traffic subset,
e.g. type of traffic, hostname, service identiers or combination
thereof, which may not be related to "coverage" footprint as defined
above. It is to be determined whether this requirement is best
addressed by scoping such capabilities in a footprint, which would be
extended to refer to traffic subsets, or through a new scoping object
that defines named traffic classes in a manner similar to named
footprints.
3. Changes to CDNI Metadata
3.1. CDNI Metadata Additional Footprint Types
Section 5 of [RFC8008] describes the FCI Capability Advertisement
Object, which includes an array of CDNI Footprint Objects. Each such
object has a footprint-type and a footprint-value, as described in
section 4.2.2.2 of [RFC8006]. This document defines additional
footprint types, beyond those mentioned in CDNI metadata [RFC8006].
3.1.1. Expression Footprint Type
The "expr" footprint type specified in Section 3.1.1.1 describes a
footprint using CDNI Metadata Expression Language as defined in
Section 3 of [CDNI-Metadata-Model-Extensions]. The data type is
added to the list of data types described in section 4.3 of
[RFC8006]. This data type may supersede the "footprintunion"
datatype defined in [RFC9388]
3.1.1.1. Expression Footprint Type Description
The footprint value is a CDNI Metadata Expression Language
expression, as defined in Section 3 of
[CDNI-Metadata-Model-Extensions].
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Type: String
Examples:
( $ep.country == "us" ) and
not $ep.ipv4addr ipmatch ( "10.1.1/24" or "10.1.2.0/24" )"
( $ep.asn = 1234 ) or ( $ep.ipv4addr ipmatch "192.168.1/24" ) or
( $ep.ipv6addr ipmatch "2001:db8:3333:4444/48" )
3.1.2. Named Footprint Type
The "named" footprint type specified in Section 3.1.2.1 describes an
addressable footprint, that can be referenced by other CDNI Metadata
objects as well as used within CDNI interfaces using CDNI Metadata
Expression Language "[CDNI-Metadata-Model-Extensions]. The data type
is added to the list of data types described in section 4.3 of
[RFC8006].
3.1.2.1. Named Footprint Type Description
The footprint value is the URI of named footprint advertised via the
FCI footprint advertised as described in Section 4.2
Type: String
Example:
"https://oc.dcdn.com/FCI/footprints/live/us"
3.2. Changes to Existing CDNI Metadata Footprint Types
As indicated in Section 2.5, resolution of complex footprint
datatypes, relies on 3rd party datasources and maybe ambiguous.
Additionally, it should be possible for dCDN to self-publish IP
address information. Such footprint types include "asn" and
"country" defined in Section 4.2.2.2 of [RFC8006], as well as
"subdivisioncode" footprint type, defined in [RFC9388]
It is hereby proposed to add an optional attribute "footprint-source"
to the footprint object, typed as array of MI FootprintSource
objects, that enumerate all footprint datasources that MUST be used
when evaluating whether an IP address belongs to the footprint in
question. If no footprint source is provided, any datasource can be
used for this purpose.
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3.3. Changes to CDNI Metadata
This section details proposed changes to the CDNI Metadata model, as
defined in Section 4 of [RFC8006]. The changes are limited to
introduction of new objects and thus backward compatibility with
[RFC8006] is preserved
3.3.1. MI NamedFootprint
NamedFootprint is a new GenericMetadata object that defined a named
footprint that can be explicitly referenced by the CDNI Metadata
objects.
- Property: footprint-def
Description: Footprint definition
Type: JSON-encoded MI Footprint object as defined in
Section 4.2.2.2 of [RFC8006]
Mandatory: Yes
- Property: subfootprints
Description: List of descendant footprints in the footprint
hierarchy
Type: Array of MI NamedFootprint objects as defined in
Section 3.3.1
Mandatory: No
- Property: footprint-name
Description: Footprint name, must be unique in same footprint
namespace
Type: String
Mandatory: Yes
- Property: footprint-uri
Description: URI pointing to the footprint definition. Can be
queried by uCDN separately
Type: String
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Mandatory: Yes
- Property: footprint-expires
Description: Timestamp for footprint definition expiration, should
be used for caching and refreshing of the footprint definition.
Type: Date-time
Mandatory: Yes
3.3.2. MI NamedFootprintNamespace
NamedFootprintName is a new GenericMetadata object that defines a
namespace containing footprints. Footprints should have unique name
within each namespace. dCDN should advertise footprints so that each
endpoint resolves unambiguously to a footprint within each namespace.
- Property: footprint-namespace
Description: Footprint namespace name
Type: String
Mandatory: Yes
- Property: footprint-type
Description: Definition of footprint type advertised in the
namespace as defined in Appendix B of [RFC8006]
Type: One of "coverage" or "resource"
Mandatory: Yes
- Property: footprints
Description: List of root footprints included in the namespace
Type: Array of MI NamedFootprint objects as defined in
Section 3.3.1
Mandatory: Yes
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3.3.3. MI FootprintSource
FootprintSource is a new GenericMetadata object that defines a
datasource that MUST be used when matching IP addresses with a
footprint.
- Property: footprint-source-type
Description: Type of datasrouce. Can be either "rfc8805" for
geolocation feeds published by dCDN in accordance with [RFC8805]
or "private" for datasource utilizing proprietary data formats
and/or APIs
Type: String
Mandatory: Yes
- Property: footprint-source-uri
Description: Footprint source URI. For "rfc8805" footprint
sources should be the URI for access of the self-published feed.
For other footprint sources, the URI should identify the footprint
source in a unique way.
Type: String
Mandatory: Yes
- Property: footprint-source-footprint-type
Description: Footprint type(s) supported by this footprint source
Type: Array of Strings, can take values of "country", "asn" or
"subdivisioncode"
Mandatory: Yes
The example of named footprint advertisement is as follows:
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{
"footprint-source-type": "rfc8805",
"footprint-source-uri": "http://noc.ietf.org/geo/google.csv"
"footprint-source-footprint-type": [ "country", "subdivisioncode" ]
}
{
"footprint-source-type": "private",
"footprint-source-uri": "https://www.maxmind.com",
"footprint-source-footprint-type": [ "country", "subdivisioncode" ]
}
{
"footprint-source-type": "private",
"footprint-source-uri": "https://tools.iplocation.net/ip-to-asn",
"footprint-source-footprint-type": [ "asn" ]
}
4. Changes to CDNI Operation
4.1. CDNI Operation Overview
The CDNI framework presumes that uCDN consumes dCDN capabilities with
footprint restrictions at the outset of uCDN delegating traffic to
dCDN. The capabilities discovered in this way are subsequently used
for metadata-driven configuration of dCDN and request routing. As an
option, uCDN and dCDN may refresh the capabilities information via
the FCI interface on periodic basis. This process is outlined in
Section 3 of [RFC7336].
This document proposes the following change to the CDNI operation:
1. dCDN advertises the capabilities and footprints via the FCI
interface. The footprint advertisement consists of MI
NamedFootprint objects, as defined in Section 3.3.1, in one or
more namespaces. The footprint advertisement contains expiration
information and URIs for every named footprint. The capabilities
advertised may be scoped to the named footprints advertised.
2. uCDN retrieves the dCDN advertised capabiities via FCI.
3. uCDN retrieves and caches the dCDN advertised footprints via FCI.
4. uCDN configures dCDN using CDNI Metadata over MI interface. The
metadata may optionally reference the footprints advertised by
dCDN.
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5. uCDN receives content request from a user agent.
6. uCDN matches user agent IP address against the cached copy of
footprint advertisement made by the dCDN and makes decision to
delegate the request to the dCDN
7. uCDN redirects the request to the dCDN by sending a response to
the user agent (either DNS or HTTP).
8. At any time following the initial retrieval of the footprint
advertisement, uCDN may refresh all or part of the cached
footprint advertisement, subject to the expiration information
provided with every footprint.
The FCI footprint advertisement allows for some footprints to be
updated more frequently than others. uCDN will require to query the
frequently changing footprint definitions only in case these
footprints affect uCDN handling of the user agent requests. Thus, it
is expected that the dCDN will not advertise high-level footprints
with low time-to-live (TTL).
4.2. FCI Advertisement
The example of named footprint advertisement is as follows:
[
{
"footprint-namespace": "default",
"footprint-type": "coverage",
"footprints": [
{
"footprint-name": "default/us",
"footprint-expires": "2023-02-09T17:32:28Z",
"footprint-uri":
"https://oc.dcdn.com/FCI/footprints/default/us",
"footprint-def": {
"footprint-type": "asn",
"footprint-value": [ "1234:1" ]
}
"footprints": [
{
"footprint-name": "default:us/us-edge",
"footprint-expires": "2023-02-09T17:32:28Z",
"footprint-uri":
"https://oc.dcdn.com/FCI/footprints/default/us/us-edge",
"footprint-def": {
"footprint-type": "expr",
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"footprint-value": [ "$ep.asn = 1234:1 and
( $ep.ipv4addr ipmatch "192.168.1/24"
or $ep.ipv6addr ipmatch "2001:db8:3333:4444/48" ) " ]
}
]
},
{
"footprint-name": "default/brasil",
"footprint-expires": "2023-02-09T17:32:28Z",
"footprint-uri":
"https://oc.dcdn.com/FCI/footprints/default/brasil",
"footprint-def": {
"footprint-type": "asn",
"footprint-value": [ "1234:2" ]
}
}
]
},
{
"footprint-namespace": "live",
"footprint-type": "coverage",
"footprints": [
{
"footprint-name": "live/us",
"footprint-expires": "2023-02-09T17:32:28Z",
"footprint-uri": "https://oc.dcdn.com/FCI/footprints/live/us",
"footprint-def": {
"footprint-type": "asn",
"footprint-value": [ "1234:1" ]
}
},
{
"footprint-name": "live/brasil",
"footprint-expires": "2023-02-09T17:32:28Z",
"footprint-uri":
"https://oc.dcdn.com/FCI/footprints/live/brasil",
"footprint-def": {
"footprint-type": "asn",
"footprint-value": [ "1234:2" ]
}
}
]
}
]
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4.3. Use of Named Footprints
The named footprints can be used in both FCI and MI footprints in the
places where CDNI Metadata objects are scoped by footprint. Thus,
the MI PrivateFeature object described in Section 2.5.2.1 of
[CDNI-Metadata-Model-Extensions] would use the named footprint
advertisement as follows:
{
"generic-metadata-type": "MI.PrivateFeatureList",
"generic-metadata-value": {
"feature": {
"feature-oid": "Broadpeak",
"feature-type": "S4Streaming",
"feature-value": {
"footprint": {
"footprint-type": "named",
"footprint-value": [ "https://oc.dcdn.com/FCI/footprints/live/us" ]
}
"activation": "ON",
"mode": "transparent",
"policy": "bandwidth-max"
}
}
}
}
5. IANA Considerations
5.1. CDNI Metadata Footprint Types
Section 7.2 of [RFC8006] creates the "CDNI Metadata Footprint Types"
subregistry within the "Content Delivery Network Interconnection
(CDNI) Parameters" registry.
This document requests the registration of the two additional
Footprint Types: "expr" and "named"
6. Security Considerations
TBD
7. References
7.1. Normative References
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[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>.
[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>.
[RFC9388] Sopher, N. and S. Mishra, "Content Delivery Network
Interconnection (CDNI) Footprint Types: Country
Subdivision Code and Footprint Union", RFC 9388,
DOI 10.17487/RFC9388, July 2023,
<https://www.rfc-editor.org/info/rfc9388>.
7.2. Informative References
[CDNI-Metadata-Model-Extensions]
"CDNI Metadata Model Extensions - Metadata Expression
Language", <https://datatracker.ietf.org/doc/html/draft-
goldstein-cdni-metadata-model-extensions-02>.
[OCWG] "Open Caching Home Page", <https://opencaching.svta.org/>.
[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>.
[RFC7337] Leung, K., Ed. and Y. Lee, Ed., "Content Distribution
Network Interconnection (CDNI) Requirements", RFC 7337,
DOI 10.17487/RFC7337, August 2014,
<https://www.rfc-editor.org/info/rfc7337>.
[RFC8805] Kline, E., Duleba, K., Szamonek, Z., Moser, S., and W.
Kumari, "A Format for Self-Published IP Geolocation
Feeds", RFC 8805, DOI 10.17487/RFC8805, August 2020,
<https://www.rfc-editor.org/info/rfc8805>.
[SVTA] "Streaming Video Technology Alliance Home Page",
<https://www.svta.org/>.
Author's Address
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Alan Arolovitch
Viasat
1295 Beacon street, Unit 249
Brookline, MA 02446
United States of America
Email: alan.arolovitch@gmail.com
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