CMSF- a CMAF compliant implementation of MOQT Streaming Format
draft-ietf-moq-cmsf-01
| Document | Type | Active Internet-Draft (moq WG) | |
|---|---|---|---|
| Author | Will Law | ||
| Last updated | 2026-06-03 | ||
| Replaces | draft-wilaw-moq-cmsf | ||
| RFC stream | Internet Engineering Task Force (IETF) | ||
| Intended RFC status | (None) | ||
| Formats | |||
| Additional resources | Mailing list discussion | ||
| Stream | WG state | WG Document | |
| Document shepherd | (None) | ||
| IESG | IESG state | I-D Exists | |
| Consensus boilerplate | Unknown | ||
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| Send notices to | (None) |
draft-ietf-moq-cmsf-01
Media Over QUIC W. Law
Internet-Draft Akamai
Intended status: Informational 3 June 2026
Expires: 5 December 2026
CMSF- a CMAF compliant implementation of MOQT Streaming Format
draft-ietf-moq-cmsf-01
Abstract
This document updates MOQT Streaming Format by defining optional
syntax and semantics for carrying CMAF-packaged media.
About This Document
This note is to be removed before publishing as an RFC.
The latest revision of this draft can be found at https://moq-
wg.github.io/cmsf/draft-wilaw-moq-cmsf.html. Status information for
this document may be found at https://datatracker.ietf.org/doc/draft-
ietf-moq-cmsf/.
Discussion of this document takes place on the Media Over QUIC
Working Group mailing list (mailto:moq@ietf.org), which is archived
at https://mailarchive.ietf.org/arch/browse/moq/. Subscribe at
https://www.ietf.org/mailman/listinfo/moq/.
Source for this draft and an issue tracker can be found at
https://github.com/moq-wg/cmsf.
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
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material or to cite them other than as "work in progress."
This Internet-Draft will expire on 5 December 2026.
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Copyright Notice
Copyright (c) 2026 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
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 . . . . . . . . . . . . . . . . . . . . . . . . 3
2. MSF Extension . . . . . . . . . . . . . . . . . . . . . . . . 3
3. CMAF Packaging . . . . . . . . . . . . . . . . . . . . . . . 3
3.1. Initialization headers . . . . . . . . . . . . . . . . . 3
3.2. Switching sets and tracks . . . . . . . . . . . . . . . . 3
3.3. Object Packaging . . . . . . . . . . . . . . . . . . . . 4
3.4. Group Packaging . . . . . . . . . . . . . . . . . . . . . 4
3.5. Catalog description . . . . . . . . . . . . . . . . . . . 4
3.5.1. CMAF packaging type . . . . . . . . . . . . . . . . . 4
3.5.2. Max SAP starting types . . . . . . . . . . . . . . . 5
3.6. Event Timelines . . . . . . . . . . . . . . . . . . . . . 5
3.6.1. SAP Type timeline . . . . . . . . . . . . . . . . . . 5
3.6.2. SAP-type timeline track example . . . . . . . . . . . 6
4. Content Protection . . . . . . . . . . . . . . . . . . . . . 7
4.1. Content Protection catalog fields . . . . . . . . . . . . 8
4.1.1. Content Protections . . . . . . . . . . . . . . . . . 8
4.1.2. Content Protection Reference IDs . . . . . . . . . . 11
4.2. Initialization data for protected tracks . . . . . . . . 11
4.3. ClearKey content protection . . . . . . . . . . . . . . . 11
5. Catalog Examples . . . . . . . . . . . . . . . . . . . . . . 12
5.1. Simulcast video tracks - 3 alternate video qualities along
with audio . . . . . . . . . . . . . . . . . . . . . . . 12
5.2. DRM-protected video with audio . . . . . . . . . . . . . 14
5.3. ClearKey-protected video . . . . . . . . . . . . . . . . 16
6. Conventions and Definitions . . . . . . . . . . . . . . . . . 18
7. Security Considerations . . . . . . . . . . . . . . . . . . . 18
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 18
9. References . . . . . . . . . . . . . . . . . . . . . . . . . 18
9.1. Normative References . . . . . . . . . . . . . . . . . . 18
9.2. Informative References . . . . . . . . . . . . . . . . . 19
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 19
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 19
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1. Introduction
CMAF compliant MOQT Streaming Format (CMSF) is a media format
designed to deliver CMAF [CMAF] and LOC [LOC] compliant media content
over MOQ Transport (MOQT) [MoQTransport]. CMSF extends MSF and
retains all the scope, capabilities and features of MSF including the
catalog format, timeline, ABR switching and LOC support. CMSF is
targeted at real-time and interactive levels of live latency, as well
as VOD content.
This document describes version 1 of the CMSF streaming format.
2. MSF Extension
All of the specifications, requirements, and terminology defined in
[MSF] apply to implementations of this extension unless explicitly
noted otherwise in this document.
3. CMAF Packaging
3.1. Initialization headers
A CMAF header is a sequence of CMAF constrained ISO BMFF boxes that
do not reference any media samples, but are associated with a CMAF
track and are necessary for initializing the decoding of the
subsequent CMAF fragments.
The header for a given MOQT Track MUST be added to the catalog by
generating an initDataList entry with a "type" of "inline", a "data"
value of the header encoded using [BASE64] and an "id" which is
unique across the initDataList items. That "id" value is then
inserted as the value of an "initRef" property in all tracks which
use that header for initialization.
3.2. Switching sets and tracks
This specification defines a direct mapping between CMAF Tracks (
[CMAF] Sect 3.2.1) and MOQT tracks ([MoQTransport] Sect 2.3).
CMAF switching sets are a set of one or more CMAF tracks (3.2.1),
where each track is an alternative encoding of the same source
content and are constrained to enable seamless track switching
(3.3.9).
Each CMAF track in a switching set MUST be transmitted as a separate
MOQT Track. The catalog entry for each of these tracks in the
switching set MUST carry a Alternate group (altGroup) key with a
common value.
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The MOQT Group numbers within these switching set tracks MUST be
media time-aligned. Mandating the track being media time-aligned
requires that the presentation time of the first media sample
contained within the first MOQT Object of each MOQT Group is
identical.
3.3. Object Packaging
The payload of each Object is subject to the following requirements:
* MUST contain at least one Movie Fragment Box (moof) followed by a
Media Data Box (mdat). This is equivalent to requiring that each
Object hold at least one CMAF Chunk. The Media Fragment Box
(moof) MUST contain a Movie Fragment Header Box (mfhd) and Track
Box (trak) with a Track ID (track_ID) matching a Track Box in the
initialization fragment.
* MAY contain multiple successive CMAF Chunks.
* MUST contain a single track.
3.4. Group Packaging
Each MOQT Group
* MUST begin with an Object containing a stream access point (SAP)
type 1 or 2.
* MUST contain one or more contiguous independently coded sequences
of media samples.
* The Group boundary MUST align with a CMAF Fragment boundary. CMAF
Fragments and CMAF Chunks MUST NOT span Groups.
3.5. Catalog description
3.5.1. CMAF packaging type
This specification extends the allowed packaging values defined in
[MSF] to include one new entry, as defined in Table 1 below:
+======+=======+===========+
| Name | Value | Reference |
+======+=======+===========+
| CMAF | cmaf | This RFC |
+------+-------+-----------+
Table 1
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Every Track entry in a CMSF catalog carrying CMAF-packaged media data
MUST declare a "packaging" type value of "cmaf".
3.5.2. Max SAP starting types
This specification adds two track-level catalog fields, as defined in
Table 2 below:
+=============================+=======================+============+
| Field | Name | Definition |
+=============================+=======================+============+
| Max Group SAP starting type | maxGrpSapStartingType | Section |
| | | 3.5.2.1 |
+-----------------------------+-----------------------+------------+
| Max Object SAP starting | maxObjSapStartingType | Section |
| type | | 3.5.2.2 |
+-----------------------------+-----------------------+------------+
Table 2
3.5.2.1. Max Group SAP starting type
Location: T Required: Optional JSON Type: Number
A number indicating the maximum SAP type the MOQT Groups in the track
start with.
3.5.2.2. Max Object SAP starting type
Location: T Required: Optional JSON Type: Number
A number indicating the maximum SAP type the MOQT Objects in the
track start with.
3.6. Event Timelines
3.6.1. SAP Type timeline
CMSF defines a special instance of an Event Timeline track, termed
the SAP Type timeline track. Its purpose is to convey information
about the distribution of Stream Access Point types and their
associated Earlist Presentation Times.
In the catalog, the SAP-type timeline track MUST include a
'packaging' value of 'eventtimeline" and MUST include an 'eventType'
value of 'org.ietf.moq.cmsf.sap'.
In the SAP Type timeline JSON payload:
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* The index reference MUST be 'l' for Location
* The data field is a JSON Array containing two integers. The first
integer defines SAP type with an allowed value of 0,1,2 or 3. The
value 0 indicates that the Object does not start with an ISOBMFF
stream access point. The value equal to 1, 2, or 3 indicates that
the Object begins with a stream access point of SAP type 1, 2, or
3, respectively. When the Object is the first Object in the
Group, the value MUST be equal to 1 or 2. The second integer
defines the earliest media presentation timestamp, rounded to the
nearest millisecond, of all media samples in the Object defined by
the Location of that record.
3.6.2. SAP-type timeline track example
This shows an example of 30-fps HEVC-encoded content, in which each
4s Group beings with SAP-type 2 (i.e., the first picture in the Group
is an IDR picture, while there may be one or more pictures in the
Group following the IDR picture in decoding order but preceding it in
output order). After 2 seconds in each Group, there is a SAP-type 3,
i.e., a CRA picture, which is associated with one or more Random
Access Skipped Leading (RASL) pictures. A small buffer of frames (10
frames at 30 fps) is skipped/discarded (RASL pictures) when the
streaming session starts from the SAP-type 3 location. In this
example, the EPT is the presentation time of the first picture after
the RASL pictures in decoding order; all pictures after the RASL
pictures can be fully correctly decoded and are thus presentable when
the streaming session starts from the SAP-type 3 location. Note that
if the streaming session starts from the start of the Group, then
these RASL pictures can be fully correctly decoded and are thus
presentable.
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[
{
"l": [0,0],
"data": [2,0]
},
{
"l": [0,60],
"data": [3,2100]
},
{
"l": [1,0],
"data": [2,4000]
},
{
"l": [1,60],
"data": [3,6100]
}
]
4. Content Protection
CMSF supports content protection using Common Encryption [CENC] for
CMAF-packaged media. This enables interoperability with existing DRM
ecosystems by reusing the signaling model established by DASH [DASH]
and the DASH-IF Encryption and Content Protection (ECCP) guidelines
[DASHIF-ECCP].
Content protection in CMSF differs from the encryption scheme defined
in [MSF] Section 4.3. While MSF defines an end-to-end encryption
mechanism using MoQ Secure Objects for LOC-packaged content, CMSF
uses ISO Common Encryption [CENC] applied at the CMAF media layer.
In CMSF, the media samples within CMAF chunks are encrypted as
specified by [CENC], and the DRM signaling is carried in the catalog
rather than in per-object headers.
A key advantage of CENC-based content protection is that decryption
can be delegated to a Content Decryption Module (CDM) operating at a
deeper system level, potentially in hardware or a trusted execution
environment. This enables robust content protection through
commercial DRM systems such as Widevine, PlayReady, and FairPlay
Streaming, where the decryption keys and decrypted media are handled
within a secure pipeline that is not accessible to the application
layer. This hardware-level protection is a requirement for high-
value content distribution and is not achievable with application-
layer encryption schemes alone.
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4.1. Content Protection catalog fields
Content protection information is signaled in the catalog at two
levels: a root-level contentProtections array containing DRM system
descriptions, and track-level references to those descriptions.
4.1.1. Content Protections
Location: R Required: Optional JSON Type: Array
A JSON array of Content Protection objects at the root level of the
catalog. Each object describes a single DRM system configuration.
Content protection information MUST NOT be duplicated at the track
level; all tracks reference the root-level entries.
Each Content Protection object contains the following fields:
4.1.1.1. Reference ID
Location: CP Required: Required JSON Type: String
A unique identifier for this content protection entry. Track entries
reference this value via the contentProtectionRefIDs field.
4.1.1.2. Default KIDs
Location: CP Required: Required JSON Type: Array of Strings
An array of default Key IDs (KIDs) expressed as UUID strings in the
format "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx". These correspond to
the default_KID values defined in [CENC] Section 5. When multiple
KIDs are present, each identifies a key used to encrypt a different
set of samples (e.g., separate keys for different track types).
4.1.1.3. Scheme
Location: CP Required: Required JSON Type: String
The Common Encryption protection scheme as defined in [CENC].
Allowed values are:
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+======+=======+=================================================+
| Name | Value | Description |
+======+=======+=================================================+
| CENC | cenc | AES-CTR full sample and sub-sample encryption |
+------+-------+-------------------------------------------------+
| CBCS | cbcs | AES-CBC pattern-based encryption with subsample |
+------+-------+-------------------------------------------------+
Table 3
The RECOMMENDED scheme for CMSF is "cbcs" as it provides better
compatibility with hardware decoders and aligns with DASH-IF ECCP
recommendations [DASHIF-ECCP].
4.1.1.4. DRM System
Location: CP Required: Required JSON Type: Object
An object describing the DRM system associated with this content
protection entry. It contains the following fields:
4.1.1.4.1. System ID
Location: DS Required: Required JSON Type: String
The DRM System ID expressed as a UUID string. Well-known system IDs
include:
+============+======================================+
| DRM System | System ID |
+============+======================================+
| Widevine | edef8ba9-79d6-4ace-a3c8-27dcd51d21ed |
+------------+--------------------------------------+
| PlayReady | 9a04f079-9840-4286-ab92-e65be0885f95 |
+------------+--------------------------------------+
| FairPlay | 94ce86fb-07ff-4f43-adb8-93d2fa968ca2 |
+------------+--------------------------------------+
| ClearKey | 1077efec-c0b2-4d02-ace3-3c1e52e2fb4b |
+------------+--------------------------------------+
Table 4
The ClearKey system ID follows the W3C EME specification and
corresponds to the DASH-IF ECCP "Explicit Clear Key Content
Protection" mechanism [DASHIF-ECCP].
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4.1.1.4.2. License URL
Location: DS Required: Optional JSON Type: Object
An object containing the URL of the license acquisition service. The
object has the following fields:
* url (String, Required): The URL of the license server.
* type (String, Optional): The license protocol type (e.g., "EME-
1.0").
4.1.1.4.3. Certificate URL
Location: DS Required: Optional JSON Type: Object
An object containing the URL of the DRM certificate service. This
field is REQUIRED for DRM systems that require a server certificate
(e.g., FairPlay Streaming). The object has the following fields:
* url (String, Required): The URL of the certificate server.
* type (String, Optional): The MIME type of the certificate resource
(e.g., "application/pkcs7-mime", "application/x-x509-ca-cert").
This corresponds to the certType attribute defined in
[DASHIF-ECCP].
4.1.1.4.4. Authorization URL
Location: DS Required: Optional JSON Type: Object
An object containing the URL of an authorization service. The object
has the following fields:
* url (String, Required): The URL of the authorization server.
* type (String, Optional): The authorization protocol type.
4.1.1.4.5. PSSH
Location: DS Required: Optional JSON Type: String
A Base64-encoded [BASE64] Protection System Specific Header (PSSH)
box as defined in [CENC] Section 8.1. The PSSH box contains DRM
system-specific initialization data needed by the client to acquire a
license. This field SHOULD be present for DRM systems that require
PSSH data (e.g., Widevine, PlayReady).
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4.1.1.4.6. Robustness
Location: DS Required: Optional JSON Type: String
A string indicating the minimum robustness level required by the DRM
system. The interpretation of this value is DRM system-specific.
4.1.2. Content Protection Reference IDs
Location: T Required: Optional JSON Type: Array of Strings
An array of Reference ID strings (see Section 4.1.1.1) identifying
which content protection entries from the root-level
contentProtections array apply to this track. When this field is
present, the track content is encrypted using Common Encryption
[CENC] and the subscriber MUST acquire appropriate licenses before
decryption.
When this field is absent, the track content is not protected by
Common Encryption.
4.2. Initialization data for protected tracks
For protected CMAF tracks, the initialization data (carried in the
catalog initDataList array (as defined in Section 3.1) MUST include
the Protection Scheme Information Box ('sinf') containing the Scheme
Type Box ('schm') and Scheme Information Box ('schi') with the Track
Encryption Box ('tenc') as specified in [CENC] Section 6. This
enables the subscriber to determine the encryption parameters
(default_isProtected, default_Per_Sample_IV_Size, default_KID) from
the initialization segment.
4.3. ClearKey content protection
For testing and development scenarios, CMSF supports ClearKey content
protection using the W3C EME ClearKey mechanism. ClearKey uses the
Common System ID "1077efec-c0b2-4d02-ace3-3c1e52e2fb4b" and follows
the DASH-IF ECCP Explicit Clear Key Content Protection (ECCP) model
[DASHIF-ECCP].
When using ClearKey:
* The systemID MUST be set to "1077efec-
c0b2-4d02-ace3-3c1e52e2fb4b".
* The laURL field SHOULD contain the URL of a ClearKey license
server that implements the EME ClearKey protocol.
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* The optional pssh field SHOULD contain a Base64-encoded PSSH box
with version 1, the Common System ID, and the KID(s) in the KID
list.
5. Catalog Examples
The following section provides non-normative JSON examples of various
catalogs compliant with this draft.
5.1. Simulcast video tracks - 3 alternate video qualities along with
audio
This example shows catalog for a media producer capable of sending 3
time-aligned video tracks for high definition, low definition and
medium definition video qualities, along with an audio track.
{
"version": "1",
"generatedAt": 1746104606044,
"tracks":[
{
"name": "hd",
"renderGroup": 1,
"packaging": "cmaf",
"isLive": true,
"targetLatency": 2000,
"initRef": "init-hd",
"role": "video",
"codec":"avc1.640028",
"width":1920,
"height":1080,
"bitrate":5000000,
"framerate":30,
"altGroup":1
},
{
"name": "md",
"renderGroup": 1,
"packaging": "cmaf",
"isLive": true,
"targetLatency": 2000,
"initRef": "init-md",
"role": "video",
"codec":"avc1.64001e",
"width":720,
"height":640,
"bitrate":3000000,
"framerate":30,
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"altGroup":1
},
{
"name": "sd",
"renderGroup": 1,
"packaging": "cmaf",
"isLive": true,
"targetLatency": 2000,
"initRef": "init-sd",
"role": "video",
"codec":"avc1.64000d",
"width":192,
"height":144,
"bitrate":500000,
"framerate":30,
"altGroup":1
},
{
"name": "audio",
"renderGroup": 1,
"packaging": "cmaf",
"isLive": true,
"targetLatency": 2000,
"initRef": "init-audio",
"role": "audio",
"codec":"mp4a.40.5",
"samplerate":48000,
"channelConfig":"2",
"bitrate":67071
}
],
"initDataList": [
{
"id": "init-hd",
"type": "inline",
"data": "AAAAHGZ0eXBjbWYyAAAAAGNtZjJpc282bXA0MQ..."
},
{
"id": "init-md",
"type": "inline",
"data": "AAAAHGZ0eXBjbWYyAAAAAGNtZjJpc282bXA0MQ..."
},
{
"id": "init-sd",
"type": "inline",
"data": "AAAAHGZ0eXBjbWYyAAAAAGNtZjJpc282bXA0MQ..."
},
{
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"id": "init-audio",
"type": "inline",
"data": "AAAAHGZ0eXBjbWYyAAAAAGNtZjJpc282bXA0MQ..."
}
]
}
5.2. DRM-protected video with audio
This example shows a catalog for a single DRM-protected video track
and an unprotected audio track. The video track is encrypted using
CBCS and references three content protection entries: Widevine,
PlayReady, and FairPlay.
{
"version": "1",
"generatedAt": 1746104606044,
"contentProtections": [
{
"refID": "1",
"defaultKID": [
"01234567-89ab-cdef-0123-456789abcdef"
],
"scheme": "cbcs",
"drmSystem": {
"systemID": "edef8ba9-79d6-4ace-a3c8-27dcd51d21ed",
"laURL": {
"url": "https://widevine-license.example.com/proxy"
},
"pssh": "AAAAP3Bzc2gAAAAA7e+LqXnWSs6jy..."
}
},
{
"refID": "2",
"defaultKID": [
"01234567-89ab-cdef-0123-456789abcdef"
],
"scheme": "cbcs",
"drmSystem": {
"systemID": "9a04f079-9840-4286-ab92-e65be0885f95",
"laURL": {
"url": "https://playready-license.example.com/auth"
},
"pssh": "AAACvnBzc2gAAAAAmgTweZhAQoar..."
}
},
{
"refID": "3",
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"defaultKID": [
"01234567-89ab-cdef-0123-456789abcdef"
],
"scheme": "cbcs",
"drmSystem": {
"systemID": "94ce86fb-07ff-4f43-adb8-93d2fa968ca2",
"laURL": {
"url": "https://fps-license.example.com/api/licenses"
},
"certURL": {
"url": "https://fps-license.example.com/cert"
}
}
}
],
"tracks": [
{
"name": "video_protected",
"packaging": "cmaf",
"isLive": true,
"buffers": {"target":1500},
"role": "video",
"renderGroup": 1,
"altGroup": 1,
"initRef": "1",
"codec": "avc3.4D401F",
"framerate": 25,
"bitrate": 581905,
"width": 1280,
"height": 720,
"contentProtectionRefIDs": ["1", "2", "3"]
},
{
"name": "audio",
"packaging": "cmaf",
"isLive": true,
"buffers": {"target":1500},
"role": "audio",
"renderGroup": 1,
"initRef": "2",
"codec": "mp4a.40.5",
"samplerate": 48000,
"channelConfig": "2",
"bitrate": 67071
}
],
"initDataList": [
{
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"id": "1",
"type": "inline",
"data": "AAAAHGZ0eXBjbWYyAAAAAGNtZjJpc282bXA0MQAA..."
},
{
"id": "2",
"type": "inline",
"data": "AAAAHGZ0eXBjbWYyAAAAAGNtZjJpc282bXA0MQAA..."
}
]
}
5.3. ClearKey-protected video
This example shows a catalog using ClearKey content protection
following the ECCP model, suitable for testing and development.
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{
"version": "1",
"generatedAt": 1746104606044,
"contentProtections": [
{
"refID": "1",
"defaultKID": [
"01234567-89ab-cdef-0123-456789abcdef"
],
"scheme": "cenc",
"drmSystem": {
"systemID": "1077efec-c0b2-4d02-ace3-3c1e52e2fb4b",
"laURL": {
"url": "https://clearkey-server.example.com/clearkey",
"type": "EME-1.0"
},
"pssh": "AAAANHBzc2gBAAAAEHfv7MCyTQKs4..."
}
}
],
"tracks": [
{
"name": "video",
"packaging": "cmaf",
"isLive": true,
"buffers": {"target":1500},
"role": "video",
"renderGroup": 1,
"initRef": "init-video",
"codec": "avc1.640028",
"framerate": 30,
"bitrate": 5000000,
"width": 1920,
"height": 1080,
"contentProtectionRefIDs": ["1"]
}
],
"initDataList": [
{
"id": "init-video",
"type": "inline",
"data": "AAAAHGZ0eXBjbWYyAAAAAGNtZjJpc282bXA0MQAA..."
}
]
}
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6. Conventions and Definitions
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.
7. Security Considerations
TODO Security
8. IANA Considerations
This document has no IANA actions.
9. References
9.1. Normative References
[BASE64] Josefsson, S., "The Base16, Base32, and Base64 Data
Encodings", RFC 4648, DOI 10.17487/RFC4648, October 2006,
<https://www.rfc-editor.org/rfc/rfc4648>.
[CENC] Standardization, I. O. for., "Information technology —
MPEG systems technologies — Part 7: Common encryption in
ISO base media file format files", ISO/IEC 23001-7:2024,
August 2024.
[CMAF] Standardization, I. O. for., "Information technology —
Multimedia application format (MPEG-A) — Part 19: Common
media application format (CMAF) for segmented media",
October 2021.
[LOC] Zanaty, M., Nandakumar, S., and P. Thatcher, "Low Overhead
Media Container", Work in Progress, Internet-Draft, draft-
ietf-moq-loc-02, 15 March 2026,
<https://datatracker.ietf.org/doc/html/draft-ietf-moq-loc-
02>.
[MoQTransport]
Nandakumar, S., Vasiliev, V., Swett, I., and A. Frindell,
"Media over QUIC Transport", Work in Progress, Internet-
Draft, draft-ietf-moq-transport-18, 12 May 2026,
<https://datatracker.ietf.org/doc/html/draft-ietf-moq-
transport-18>.
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[MSF] Law, W. and S. Nandakumar, "MOQT Streaming Format", Work
in Progress, Internet-Draft, draft-ietf-moq-msf-01, 2 June
2026, <https://datatracker.ietf.org/doc/html/draft-ietf-
moq-msf-01>.
[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/rfc/rfc2119>.
[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/rfc/rfc8174>.
9.2. Informative References
[DASH] Standardization, I. O. for., "Information technology —
Dynamic adaptive streaming over HTTP (DASH) — Part 1:
Media presentation description and segment formats.", ISO/
IEC 23009-1:2022, August 2022.
[DASHIF-ECCP]
Forum, D. I., "DASH-IF Implementation Guidelines:
Encryption and Content Protection (ECCP)", 2023,
<https://dashif.org/docs/DASH-IF-ECCP-v1.0.0.pdf>.
Acknowledgments
TODO acknowledge.
Author's Address
Will Law
Akamai
Email: wilaw@akamai.com
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