Internet DRAFT - draft-ietf-cdni-protected-secrets-metadata
draft-ietf-cdni-protected-secrets-metadata
Content Delivery Networks Interconnection B. Rosenblum
Internet-Draft Vecima
Intended status: Standards Track 1 March 2024
Expires: 2 September 2024
CDNI Protected Secrets Metadata
draft-ietf-cdni-protected-secrets-metadata-01
Abstract
This document defines a simple mechanism for protected secret data
(such as salt values or encryption keys) that may be embedded in
configuration metadata or capabilities advertisements.
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 2 September 2024.
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Copyright (c) 2024 IETF Trust and the persons identified as the
document authors. All rights reserved.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Requirements . . . . . . . . . . . . . . . . . . . . . . . . 4
3. Metadata Objects . . . . . . . . . . . . . . . . . . . . . . 4
3.1. MI.SecretStore . . . . . . . . . . . . . . . . . . . . . 4
3.2. MI.SecretStoreTypeEmbedded . . . . . . . . . . . . . . . 5
3.3. MI.SecretStoreTypeHashiCorpVault . . . . . . . . . . . . 6
3.4. MI.SecretValue . . . . . . . . . . . . . . . . . . . . . 7
3.5. MI.SecretCertificate . . . . . . . . . . . . . . . . . . 9
4. Capabilities Objects . . . . . . . . . . . . . . . . . . . . 10
4.1. FCI.SecretStore . . . . . . . . . . . . . . . . . . . . . 10
4.2. FCI.SecretCertificate . . . . . . . . . . . . . . . . . . 11
5. Workflow Examples . . . . . . . . . . . . . . . . . . . . . . 12
5.1. Workflow: dCDN -> uCDN Embedded . . . . . . . . . . . . . 13
5.2. Workflow: uCDN -> dCDN Embedded . . . . . . . . . . . . . 14
5.3. Workflow: Embedded Cleartext (uCDN and dCDN) . . . . . . 15
5.4. Workflow: dCDN -> uCDN Vault . . . . . . . . . . . . . . 15
5.5. Workflow: uCDN -> dCDN Vault . . . . . . . . . . . . . . 16
6. Security Considerations . . . . . . . . . . . . . . . . . . . 16
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 16
7.1. CDNI Payload Types . . . . . . . . . . . . . . . . . . . 16
8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 17
9. Normative References . . . . . . . . . . . . . . . . . . . . 17
10. Informative References . . . . . . . . . . . . . . . . . . . 18
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 18
1. Introduction
Certain objects in both the FCI and MI interfaces encapsulate
sensitive values, such as credentials and access keys, which should
not necessarily be accessible to all parties that can view the
advertisement and configuration payloads.
This document defines two mechanisms to enclose secret values in the
context of other FCI and MI objects that may only be viewed by the
intended recipients, including embedded secrets encrypted using a
certificate supplied by a counterparty and secrets stored in an
external service (support defined in this draft is specifically for
HashiCorp Vault), which are accessed via a specified path and a key
ID. Refer to [HCVAULT] documentation.for details.
Either side can share secrets, and the functionality is the same for
both sides,, so the FCI capabilities are wrappers around the MI
objects, similar to how FCI footprints (used in [RFC8008]) reutilize
the MI.Footprint and registry defined in [RFC8006]
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The public certificate for the downstream content delivery network
(dCDN) is shared via FCI.SecretCertificate and the certificate for
the upstream content delivery network (uCDN) is shared via
MI.SecretCertificate.
Overview of the workflow for embedded secrets:
* uCDN receives an advertisement with FCI.SecretStore and
FCI.SecretCertificate. As the uCDN has not yet provided a
certificate, any embedded secret values in the advertisement are
omitted; the dCDN is not yet able to encrypt the secrets, so no
secrets are present.
* uCDN provides configuration including MI.SecretStore and
MI.SecretValue with values encrypted using the dCDN certificate.
* uCDN receives an updated capabilities advertisement; having
provided an MI.SecretCertificate, the advertisement SHOULD now
contain populated MI.SecretValue objects if secret values are
utilized, encrypted with the provided certificate.
┌────┐ ┌────┐
│uCDN│ │dCDN│
└────┘ └────┘
| Retrieve FCI.SecretStore and FCI.SecretCertificate |
|--------------------------------------------------------------->|
| |
|---- |
| | Encrypt secrets using provided FCI.SecretCertificate |
|<--- |
| |
| Provide encrypted secrets via MI.SecretValue |
|--------------------------------------------------------------->|
| |
| Provide MI.SecretStore and MI.SecretCertificate |
|--------------------------------------------------------------->|
| |
| ----|
| Encrypt secrets using provided MI.SecretCertificate | |
| --->|
| |
| Retrieve FCI.SecretValue with encrypted secrets |
|--------------------------------------------------------------->|
| |
┌────┐ ┌────┐
│uCDN│ │dCDN│
└────┘ └────┘
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Figure 1: Bi-directional Protect Secrets Workflow, Embedded Store
Type
Detailed workflow examples, including modes that reference external
services or contain secret values in plaintext, are available in the
Workflow Examples (Section 5) section.
The MI.SecretValue objects are utilized in the FCI and MI interfaces,
where secrets must be referenced.
Certificates can be validated based on signatures in production
environments, and self-signed certificates can be accepted in
testing/lab environments. With this model, no out-of-band
communication is required to share secrets.
2. Requirements
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119].
3. Metadata Objects
3.1. MI.SecretStore
MI.SecretStore instructs the counterparty how to dereference the
value of any MI.SecretValue objects linked to the store.
For embedded stores, MI.SecretStore identifies the certificate used
for encrypting the values. For external stores (e.g., HashiCorp
Vault), MI.SecretStore specifies the service endpoint that should be
used in conjunction with the MI.SecretValue key path to obtain the
secure data.
Property: secret-store-id
* Description: A unique identifier for this store configuration that
is referenced from linked MI.SecretValue objects.
* Type: String
* Mandatory-to-Specify: Yes
Property: secret-store-type
* Description: A type discriminator for the configuration object,
this property specifies whether the linked MI.SecretValue objects
contain embedded secret objects or reference an external store.
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* Type: String. Either "MI.SecretStoreTypeEmbedded" or
"MI.SecretStoreTypeHashiCorpVault".
* Mandatory-to-Specify: Yes
Property: secret-store-config
* Description: The appropriate configuration object for the
specified store type.
* Type: Object, with type specified by the secret-store-type
property.
* Mandatory-to-Specify: Yes
3.2. MI.SecretStoreTypeEmbedded
MI.SecretStoreTypeEmbedded contains the configuration necessary to
decrypt embedded secrets in MI.SecretValue.
The only currently supported encrypted message format is
Cryptographic Message Syntax (CMS) as defined in [RFC5652] Messages
MUST be CMS type "EnvelopedData" and Base64 encoded.
A cleartext format is also defined for testing purposes. In this
case, the value of an MI.SecretValue object's secret-value property
is the cleartext secret. It is NOT RECOMMENDED to use the cleartext
format in production environments.
Property: format
* Description: The format of the embedded encrypted message.
* Type: String. Either "cms" or "cleartext".
* Mandatory-to-Specify: Yes
Property: secret-certificate-id
* Description: The ID of the MI.SecretStoreCertificate used to
encrypt secret messages linked with this store configuration.
* Type: String
* Mandatory-to-Specify: No
The following is an example of MI.SecretStoreTypeEmbedded specifying
use of CMS:
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{
"secret-store-id": "store-1",
"secret-store-type": "MI.SecretStoreTypeEmbedded",
"secret-store-config": {
"format": "cms",
"secret-certificate-id": "cert-1"
}
}
Figure 2
3.3. MI.SecretStoreTypeHashiCorpVault
MI.SecretStoreTypeHashiCorpVault contains the configuration necessary
to reference secrets stored in an external instance of a HashiCorp
Vault KV store [HCVAULT].
MI.SecretValue objects reference secrets stored in the Vault using
the secret-path property to identify the path and property key. See
the MI.SecretValue (Section 3.4) section for details.
Property: endpoint
* Description: The base URL of the Vault instance.
* Type: String
* Mandatory-to-Specify: Yes
Property: namespace
* Description: The Vault namespace in which secret lookups should be
performed.
* Type: String
* Mandatory-to-Specify: Yes
Property: version
* Description: The Vault KV version.
* Type: Integer. Valid values: 1 or 2.
* Mandatory-to-Specify: Yes
The following is an example of MI.SecretStoreTypeHashiCorpVault
specifying a version KV-V1 Vault:
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{
"secret-store-id": "store-2-vaultv1",
"secret-store-type": "MI.SecretStoreTypeHashiCorpVault",
"secret-store-config": {
"endpoint": "https://vault.example.com/v1/secret",
"version": 1,
"namespace": "customer-1"
}
}
Figure 3
The following is an example of MI.SecretStoreTypeHashiCorpVault
specifying a version KV-V2 Vault:
{
"secret-store-id": "store-3-vaultv2",
"secret-store-type": "MI.SecretStoreTypeHashiCorpVault",
"secret-store-config": {
"endpoint": "https://vault.example.com/v1/secret",
"version": 2,
"namespace": "customer-1"
}
}
Figure 4
3.4. MI.SecretValue
MI.SecretValue may be used in any FCI or MI object where sensitive
data must be transmitted only to intended recipients.
Property: secret-store-id
* Description: The ID of MI.SecretStore that contains the
configuration defining how to decrypt or access the referenced
secret.
* Type: String
* Mandatory-to-Specify: Yes
Property: secret-value
* Description: Used only for embedded secrets, the Base64 encoded
value of a CMS message or the cleartext string, depending on the
defined MI.SecretStore configuration.
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* Type: String
* Mandatory-to-Specify: No
Property: secret-path
* Description: Used only for HashiCorp Vault secrets, the path, not
including namespace, to the secret, including the key of the
particular property to access as the last path parameter.
* Type: String
* Mandatory-to-Specify: No
Property: timeout
* Description: If this property is present and the elapsed time
since last retrieving the secret value has exceeded this timeout,
any cached instance of this secret value MUST be discarded and
fetched again from the associated secret store.
* Type: Integer duration in seconds.
* Mandatory-to-Specify: No
The following is an example of MI.SecretValue specifying an embedded
value:
{
"secret-store-id": "store-1-cms",
"secret-value": "MIIBiQYJKoZIhvcNAQcDoIIBejCCAXYCAQAxggEhMIIBHQIBAD
AFMAACAQEwDQYJKoZIhvcNAQEBBQAEggEApJeXzsUS1jbAyNtQiJ9um9IMIHW5B2g+gHn
XdNSTyd33OEfTR6yLSZihBlFbHpY3qSzK1CX7RF5Oz3SqLDW+r3i1D/aHbVXwQbviWHEv
Hterql8l9VDm2FCNaDx5vihdbtvng3+/vdJNNMMhmovwZL5uhPsK81DkKwZCvznMMWt8Y
dNSFGT62f73ash7Eg/mS54IUyYOJHYrXEkRLSjvl0j+JqcIR8hCOCA78+5bS4MgfdsS9x
xSwQTrPru6EdTivMDKE/jlKg7li8lWdirWqtv0za5gLmH5T+zslXIoklwERAE50Jj8FxZ
D98EikKH8DAa+JeFsBm6Z1+yVFsWucTBMBgkqhkiG9w0BBwEwHQYJYIZIAWUDBAEqBBBw
s1riXA6m336zRbsiKtrVgCA267133v2zD/wjFQHXrKSJfd/2YJaxPskgdmQaVlgWCw=="
}
Figure 5
The following is an example of MI.SecretValue for a Vault:
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{
"secret-store-id": "store-2-vaultv1",
"secret-path": "bar/baz/importantsecret",
"timeout": 3600,
}
Figure 6
3.5. MI.SecretCertificate
MI.SecretCertificate is used to share an [X.509] certificate to be
utilized for encrypting embedded secret messages.
In lab and testing environments, this certificate MAY be self-signed,
depending on participant agreement.
In production environments, this SHOULD be a certificate signed by an
appropriate certificate authority (CA) and validated by the
counterparty.
Property: certificate-id
* Description: A unique ID for this certificate that can be
referenced from a corresponding MI.SecretStore configuration
defined by a counterparty.
* Type: String
* Mandatory-to-Specify: Yes
Property: certificate-value
* Description: The Base64 encoded certificate.
* Type: String
* Mandatory-to-Specify: Yes
The following is an example of MI.SecretCertificate:
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{
"certificate-id": "store-1",
"certificate-value": "MIIDZTCCAk2gAwIBAgIUFJokJzAxDgUGsBd8uhSblpMwS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"
}
Figure 7
4. Capabilities Objects
These objects are simple capability wrappers around the MI objects
defined in this specification.
4.1. FCI.SecretStore
FCI.SecretStore instructs the uCDN how to dereference the value of
any MI.SecretValue objects linked to the store from other FCI objects
via an embedded MI.SecretValue object. For further details, see the
MI.SecretStore (Section 3.1) section.
The following is an example of FCI.SecretStore:
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{
"capabilities": [
{
"capability-type": "FCI.SecretStore",
"capability-value": {
"secret-store-id": "store-1",
"secret-store-type": "MI.SecretStoreTypeEmbedded",
"secret-store-config": {
"format": "cms"
}
}
}
]
}
Figure 8
4.2. FCI.SecretCertificate
FCI.SecretCertificate is used to share an [X.509] certificate to be
utilized for encrypting embedded secret messages via an embedded
MI.SecretCertificate object. For further details, see the
MI.SecretCertificate (Section 3.5) section.
The following is an example of FCI.SecretCertificate:
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{
"capabilities": [
{
"capability-type": "FCI.SecretCertificate",
"capability-value": {
"certificate-id": "store-1",
"certificate-value": "MIIDZTCCAk2gAwIBAgIUFJokJzAxDgUGsBd8uhS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"
}
}
]
}
Figure 9
5. Workflow Examples
The facilities in this document can be used for simple and
bidirectional exchange of secret values between uCDN and dCDN
participants in an Open Caching system. The embedded model provides
for a secret exchange without reference to out-of-band services,
while the Vault support allows for external reference to secrets
stored in a HashiCorp Vault.
Participants utilizing a secret distribution method or service not
supported here MAY define a Private Feature MI object [SVTA2038] with
the necessary configuration for that method or service and then
utilize that MI object within MI.SecretStore and FCI.SecretStore
Provided below are workflow examples for uCDN -> dCDN and dCDN ->
uCDN exchanges of secret values.
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Consideration is needed when addressing key rollover, expiration, and
revocation in the embedded model. The RECOMMENDED workflow for key
rollover is as follows:
* When the recipient of a secret provides an updated configuration
that no longer contains an MI.SecretCertificate with an ID
referenced in an MI.SecretStore used by MI.SecretValue objects,
those MI.SecretValue objects SHOULD be reduced to an object with
no contained secret-value property as they would be in the initial
state before any certificate had been provided.
* If the recipient of a secret then provides a new
MI.SecretCertificate object, the sender of the secret SHOULD
update its MI.SecretStore to reference the new certificate-id and
then update any referencing MI.SecretValue objects to include an
updated secret-value property that contains the newly encrypted
values.
5.1. Workflow: dCDN -> uCDN Embedded
1. The dCDN advertises FCI.SecretStore with a store-type of
MI.SecretStoreTypeEmbedded; other FCI objects may contain
MI.SecretValue objects that reference the store-id.
MI.SecretValue objects do not presently contain a secret-value
property.
2. The uCDN pushes the MI configuration with an
MI.SecretCertificate.
3. The dCDN updates the advertised FCI.SecretStore with a
certificate-id property that references the dCDN
MI.SecretCertificate; any MI.SecretValue objects in other FCI
objects now contain a secret-value property with the CMS
encrypted secret.
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┌────┐ ┌────┐
│uCDN│ │dCDN│
└────┘ └────┘
| Retrieve FCI.SecretStore |
|--------------------------------------------------------------->|
| |
| Provide MI.SecretCertificate |
|--------------------------------------------------------------->|
| |
| ----|
| Encrypt secrets using provided MI.SecretCertificate | |
| --->|
| |
| Retrieve FCI.SecretValue with encrypted secrets |
|--------------------------------------------------------------->|
| |
┌────┐ ┌────┐
│uCDN│ │dCDN│
└────┘ └────┘
Figure 10: Figure 2: dCDN -> uCDN Workflow, Embedded Store Type
5.2. Workflow: uCDN -> dCDN Embedded
1. The dCDN advertises an FCI.SecretCertificate.
2. The uCDN pushes the MI configuration containing MI.SecretStore
with a store-type of MI.SecretStoreTypeEmbedded and a
certificate-id referencing the FCI.SecretCertificate advertised
by the uCDN. Other MI objects may contain MI.SecretValue objects
with a secret-value property containing the CMS encrypted secret.
┌────┐ ┌────┐
│uCDN│ │dCDN│
└────┘ └────┘
| Retrieve FCI.SecretCertificate |
|--------------------------------------------------------------->|
| |
|---- |
| | Encrypt secrets using provided FCI.SecretCertificate |
|<--- |
| |
| Provide MI.SecretStore and MI.SecretValue objects |
|--------------------------------------------------------------->|
| |
┌────┐ ┌────┐
│uCDN│ │dCDN│
└────┘ └────┘
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Figure 11: Figure 3: Figure 3: uCDN -> dCDN Workflow, Embedded Store
5.3. Workflow: Embedded Cleartext (uCDN and dCDN)
1. An MI.SecretStoreTypeEmbedded has a defined format of
"cleartext".
2. Any MI.SecretValue objects that reference the cleartext store
contain a secret-value property with the unencrypted secret.
┌────┐ ┌────┐
│uCDN│ │dCDN│
└────┘ └────┘
| Retrieve FCI.SecretStore ("cleartext") and FCI.SecretValue |
|--------------------------------------------------------------->|
| |
| Provide MI.SecretStore ("cleartext") and MI.SecretValue |
|--------------------------------------------------------------->|
| |
┌────┐ ┌────┐
│uCDN│ │dCDN│
└────┘ └────┘
Figure 12: Figure 4: Embedded Cleartext Workflow
5.4. Workflow: dCDN -> uCDN Vault
The dCDN advertises an FCI.SecretStore with an appropriate
configuration for accessing an instance of a HashiCorp Vault
accessible to the uCDN. Other FCI objects may contain MI.SecretValue
objects that reference the FCI.SecretStore and a secret-path property
specifying the secret to retrieve.
┌────┐ ┌─────┐ ┌────┐
│uCDN│ │Vault│ │dCDN│
└────┘ └─────┘ └────┘
| Retrieve FCI.SecretStoreTypeHashiCorpVault | |
| and FCI.SecretValue objects | |
|--------------------------------------------------->| |
| | |
| Retrieve secrets using path provided | |
| in FCI.SecretValue objects | |
|----------------------------------------------------|---------->|
| | |
┌────┐ ┌─────┐ ┌────┐
│uCDN│ │Vault│ │dCDN│
└────┘ └─────┘ └────┘
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Figure 13: Figure 5: dCDN -> uCDN Workflow, HashiCorp Vault Store
5.5. Workflow: uCDN -> dCDN Vault
The uCDN provides the MI configuration, including an MI.SecretStore
with appropriate configuration for accessing an instance of a
HashiCorp Vault accessible to the dCDN. Other MI objects may contain
MI.SecretValue objects that reference the MI.SecretStore and a
secret-path property specifying the secret to retrieve.
┌────┐ ┌────┐ ┌─────┐
│uCDN│ │dCDN│ │Vault│
└────┘ └────┘ └─────┘
| | |
| Provide MI.SecretStoreTypeVault | |
| and MI.SecretValue objects | |
|-------------------------------->| |
| | |
| | Retrieve secrets using path |
| | provided in MI.SecretValue |
| | objects |
| |----------------------------->|
| | |
┌────┐ ┌────┐ ┌─────┐
│uCDN│ │dCDN│ │Vault│
└────┘ └────┘ └─────┘
Figure 14: Figure 6: uCDN -> dCDN Workflow, HashiCorp Vault Store
6. Security Considerations
The FCI and MI objects defined in the present document are
transferred via the interfaces defined in CDNI [RFC8006] which
describes how to secure these interfaces protecting integrity and
confidentiality while ensuring the authenticity of the dCDN and uCDN.
7. IANA Considerations
7.1. CDNI Payload Types
This document requests the registration of the following entries
under the "CDNI Payload Types" registry hosted by IANA:
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+----------------------------+---------------+
| Payload Type | Specification |
+----------------------------+---------------+
| MI.SecretStore | RFCthis |
+----------------------------+---------------+
| MI.SecretStoreTypeEmbedded | RFCthis |
+----------------------------+---------------+
| MI.SecretStoreTypeVault | RFCthis |
+----------------------------+---------------+
| MI.SecretValue | RFCthis |
+----------------------------+---------------+
| MI.SecretCertificate | RFCthis |
+----------------------------+---------------+
| FCI.SecretStore | RFCthis |
+----------------------------+---------------+
| FCI.SecretCertificate | RFCthis |
+----------------------------+---------------+
Table 1: CDNI Payload Types
8. Acknowledgements
The authors would like to express their gratitude to the members of
the Streaming Video Technology Alliance [SVTA] Open Caching Working
Group for their guidance / contribution / reviews ...)
Particulary the following people contribute in one or other way to
the content of this draft:
* Chris Lemmons (Comcast)
* Glenn Goldstein (Lumen)
* Rajeev RK (picoNETS)
* Yoav Gressel (Qwilt)
* Arnon Warshavsky (Qwilt)
* Alfonso Siloniz (Telefonica)
9. Normative References
[HCVAULT] HashiCorp, "Vault Documentation",
<https://developer.hashicorp.com/vault/docs>.
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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>.
[RFC5652] Housley, R., "Cryptographic Message Syntax (CMS)", STD 70,
RFC 5652, DOI 10.17487/RFC5652, September 2009,
<https://www.rfc-editor.org/info/rfc5652>.
[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>.
[X.509] ITU, "X.509", February 2011,
<http://www.itu.int/rec/T-REC-X.509>.
10. Informative References
[SVTA] SVTA, "Streaming Video Technology Alliance Home Page",
<https://www.svta.org>.
[SVTA2038] SVTA, "Private Features Metadata",
<https://svta.org/documents/SVTA2038>.
Author's Address
Ben Rosenblum
Vecima
United States of America
Email: ben@rosenblum.dev
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