[DRAFT] Web Real-Time Communications Working Group Charter

This is draft revised charter for the W3C WebRTC Working Group under review by the W3C Advisory Committee.

The mission of the Web Real-Time Communications Working Group is to define client-side APIs to enable Real-Time Communications in Web browsers.

These APIs should enable building applications that can be run inside a browser, requiring no extra downloads or plugins, that allow communication between parties using audio, video and supplementary real-time communication, without having to use intervening servers (unless needed for firewall traversal, or for providing intermediary services). APIs enabling supplementary functions, such as recording, image capture and screen sharing are also in scope.

Join the Web Real-Time Communications Working Group.

This proposed charter is available on GitHub. Feel free to raise issues.

Start date	[dd monthname yyyy] (date of the "Call for Participation", when the charter is approved)
End date	31 March 2020
Charter extension	See Change History.
Chairs	Bernard Aboba Harald Alvestrand Stefan Håkansson
Team Contacts	Dominique Hazaël-Massieux Vivien Lacourba (0.4 FTE)
Meeting Schedule	Teleconferences: approximately 1 per month Face-to-face: we will meet during the W3C's annual Technical Plenary week; additional face-to-face meetings may be scheduled by consent of the participants, usually no more than 3 per year.

Scope

Enabling real-time communications between Web browsers require the following client-side technologies to be available:

API functions to explore device capabilities, e.g. camera, microphone, speakers,
API functions to capture media from local devices (e.g. camera and microphone, but also output devices such as a screen),
API functions for encoding and other processing of those media streams,
API functions for accessing the data in these media streams,
API functions for transferring data between peers,
API functions for establishing direct peer-to-peer connections, including firewall/NAT traversal,
API functions for decoding and processing (including echo canceling, stream synchronization and a number of other functions) of those streams at the incoming end,
Delivery to the user of those media streams via local screens and audio output devices (partially covered with HTML5).

The working group will address issues related to using these functions in various contexts on the Web platform, such as:

Traditional Web pages
Web Workers of various types
Iframes, with appropriate access controls
Applications that span multiple pages
Pages, workers and frames specifying content security policies or other security mechanisms that should impact the use of these APIs

Out of Scope

The definition of the network protocols used to establish the connections between peers is out of scope for this group; in general, it is expected that protocols considerations will be handled in the IETF.

The definition of any new codecs for audio and video is out of scope.

Success Criteria

To advance to Proposed Recommendation, each specification is expected to have two independent implementations of each feature defined in the specification.

To advance to Proposed Recommendation, interoperability between the independent implementations (that is, bidirectional audio and video communication as well as data transfer between the implementations) should be demonstrated.

Deliverables

More detailed milestones and updated publication schedules are available on the group home page.

Draft state indicates the state of the deliverable at the time of the charter approval. Expected completion indicates when the deliverable is projected to become a Recommendation, or otherwise reach a stable state.

Normative Specifications

The Working Group will deliver specifications that cover at least the following functions, unless they are found to be fully specified within other Working Groups' finished results:

Media Stream Functions: API functions to manipulate media streams for interactive real-time communications, connecting various processing functions to each other, and to media devices and network connections, including media manipulation functions for e.g. allowing to synchronize streams. Supplementary functions such as recording of media streams are also in scope.
Audio Stream Functions: An extension of the Media Stream Functions to process audio streams, to enable features such as automatic gain control, mute functions and echo cancellation.
Video Stream Functions: An extension of the Media Stream Functions to process video streams, to enable features such as bandwidth limiting, image manipulation or "video mute".
Functional Component Functions: API functions that allow to query for the components present in an implementation, instantiate them, and connect them to media streams.
Data Access Functions: API functions that allow Web applications to access and manipulate data in media streams.
Data Transfer Functions: API functions to provide interfaces that enable the transfer of data between peers, Included in this category are API functions for message-based as well as stream-based communications.
The WG will consider any necessary API changes or extensions to enable use of more than one data transfer protocol to support the data transfer functions.
P2P Connection Functions: API functions to provide interfaces that enable the conveyance of parameters necessary to establish peer to peer connections, based on the protocols selected by the IETF RTCWeb Working Group. Included in this category are also API functions to allow identification of the peer.

The Working Group may decide to group the specified functions in one or more specifications, and to develop extensions to its existing specifications to bring additional functionality identified as needed.

The Working Group has already started and will continue work on the following specifications:

WebRTC 1.0: Real-time Communication Between Browsers: JavaScript APIs to allow media and data to be sent to and received from another browser or device implementing the appropriate set of real-time protocols; Adopted Candidate Recommendation: Candidate Recommendation 02 November 2017; Reference Draft: Candidate Recommendation 02 November 2017
associated Call for Exclusion on 02 November 2017 ended on 01 January 2018
Produced under 2015 WebRTC Working Group Charter
Media Capture and Streams: JavaScript APIs that allow local media, including audio and video, to be requested from a platform; Adopted Candidate Recommendation: Candidate Recommendation 03 October 2017; Reference Draft: Candidate Recommendation 03 October 2017
associated Call for Exclusion on 03 October 2017 ended on 02 December 2017
Produced under 2015 WebRTC Working Group Charter
MediaStream Recording: a JavaScript API to record MediaStreams; Adopted Working Draft: 21 June 2017; Reference Draft: Working Draft 08 September 2015
associated Call for Exclusion on 06 February 2013 ended on 05 July 2013
Produced under 2011 WebRTC Working Group Charter
"MediaStream Image Capture": a JavaScript API to capture still images from a video MediaStream; Adopted Working Draft: 21 June 2017; Reference Draft: Working Draft 09 July 2013
associated Call for Exclusion on 09 July 2013 ended on 06 December 2013
Produced under 2011 WebRTC Working Group Charter
Media Capture Depth Stream Extensions: An extension to the Media Capture and Streams API to capture depth streams (e.g. from 3D cameras); Adopted Working Draft: 18 April 2017; Reference Draft: Working Draft 08 December 2015
associated Call for Exclusion on 07 October 2014 ended on 06 March 2015
Produced under 2011 WebRTC Working Group Charter
Identifiers for WebRTC's Statistics API: JavaScript APIs that allow access to statistical information about a peer-to-peer connection established via the WebRTC API; Adopted Working Draft: 31 January 2018; Reference Draft: Working Draft 21 October 2014
associated Call for Exclusion on 23 October 2014 ended on 20 March 2015
Produced under 2011 WebRTC Working Group Charter
Audio Output Devices API: JavaScript APIs that let a Web application manage how audio is rendered on the user audio output devices; Adopted Candidate Recommendation: Candidate Recommendation 03 October 2017; Reference Draft: Candidate Recommendation 03 October 2017
associated Call for Exclusion on 03 October 2017 ended on 02 December 2017
Produced under 2015 WebRTC Working Group Charter
Screen Capture: An extension to the Media Capture and Streams API to use a user's display, or parts thereof, as the source of a MediaStream.; Adopted Working Draft: 14 July 2016; Reference Draft: Working Draft 10 February 2015
associated Call for Exclusion on 10 February 2015 ended on 10 July 2015
Produced under 2011 WebRTC Working Group Charter
Media Capture from DOM Elements: An extension to DOM elements to allow to capture a media stream from their content; Adopted Working Draft: 06 September 2017; Reference Draft: Working Draft 19 February 2015
associated Call for Exclusion on 19 February 2015 ended on 19 July 2015
Produced under 2011 WebRTC Working Group Charter
DSCP Control API: An extension to the WebRTC 1.0 API to enable experimentation with QoS marking.; Draft state: Editor's draft

The preferred mode of adding new features is by means of extension specifications, rather than new features in the existing specs. At appropriate times, the WG may choose to redistribute the work between documents - by splitting, merging or repartitioning the work as appropriate.

By the end of the charter period, the WG expects to have a small number of "core" specifications, which allows useful applications to be built using only those specifications, and a series of "extension" specifications that extend the applicability of the APIs specified to more applications.

This work will be done in collaboration with the IETF. The W3C will define APIs to ensure that application developers can control the components or the architecture for selection and profiling of the wire protocols that have been produced by the IETF Real-Time Communication in WEB-browsers (RTCWeb) Working Group. While the specified API Functions will not constrain implementations into supporting a specific profile, they will be compatible with the Profile that is specified by the RTCWeb Working Group.

The highest priority of the group in this charter period will be to get the core recommendations progressed towards Recommendation status. To that end, features that are not demonstrated to be implemented by at least two browsers withih the timeframes indicated will be removed from the specifications. Depending on their nature, they may be republished as extension specification, or simply dropped.

If such removal would compromise the ability to deliver on the requirements specified in this charter, the group may choose to recharter in order to revise its requirements.

As the name indicates, WebRTC 1.0: Real-time Communication Between Browsers is a first version of APIs for real-time communication, sometimes referred to as the PeerConnection API. The activities in the ORTC (Object Real-time Communications) Community Group indicate that there is interest in additional APIs to provide more direct control over WebRTC than what the PeerConnection API offers.

In recognition of this interest, the Working Group intends to start work on a new set of object-oriented APIs for real-time communication.

In developing these new APIs, the Working Group will adhere to the following principles:

Direct control: The new APIs are intended to provide direct control over the details of real-time communication, where the application can directly specify how information should be transmitted, without any built-in negotiation semantics.
Standalone operation: The new APIs will be complete enough to allow applications to write solely to the new APIs to complete common tasks.
Backwards-compatibility: The new APIs will extend the WebRTC 1.0 APIs, rather than replace them. Applications that use the PeerConnection API will continue to function, unless there is a clear and compelling reason to deprecate specific 1.0 functionality.
Feature independence: Features may be introduced in the new APIs that are not available when using the PeerConnection API.

A use-case document will be developed to clarify the functionality that the new APIs are to provide.

The Working Group will take the work done by the ORTC Community Group as a source of input, and when contemplating similar APIs in the Working Group, make efforts to align with the ORTC CG on API methodologies and nomenclature. This may include scheduled design meetings with relevant WG and CG stakeholders to foster convergence of the APIs.

The specified API Functions and the requirements on their implementation must offer functionality that ensures that users' expectations of privacy and control over their devices are met - this includes, but is not limited to, ensuring that users can control what local devices an application can access for capturing media, and are able to at any time revoke that access.

Similarly, all the deliverables must address issues of security. The security and privacy goals and requirements will be harmonized with those developed by the IETF RTCWeb Working Group.

Similarly, all deliverables must address issues of accessibility including relevant requirements listed in the Media User Accessibility Requirements document (MAUR), such as multiple well-synchronized instances of the same media type. The accessibility goals and requirements will be developed in coordination with the Accessible Platform Architectures Working Group.

Other Deliverables

A comprehensive test suite for all features of a specification is necessary to ensure the specification's robustness, consistency, and implementability, and to promote interoperability between User Agents. Therefore, each specification must have a companion test suite, which should be completed by the end of the Last Call phase, and must be completed, with an implementation report, before transition from Candidate Recommendation to Proposed Recommendation. Additional tests may be added to the test suite at any stage of the Recommendation track, and the maintenance of a implementation report is encouraged.

In particular, since WebRTC deals with communications, specific attention will be brought to the interoperability testing of the WebRTC API implementations (both browser-to-browser and browser-to-native).

Other non-normative documents may be created such as:

Primers
Requirements and use case document for specifications
Non-normative group notes

Given sufficient resources, this Working Group should review other Working Groups' deliverables that are identified as being relevant to the Working Group's mission.

Timeline

The group's home page provides current data about all of the group's specifications. Although the group expects all of its active deliverables to progress during this charter period, the charter does not include detailed milestone data for each specification because such data is speculative and easily becomes out of date. The Working Group does expect the following to occur:

Media Capture and Streams: updated Candidate Recommendation in Q2 2018, Proposed Recommendation in Q4 2018, Recommendation in Q1 2019
WebRTC 1.0: updated Candidate Recommendation in Q4 2018, Proposed Recommendation in Q3 2019, Recommendation in Q4 2019
MediaStream Recording: Candidate Recommendation in Q3 2018
Media Capture From DOM Element: Candidate Recommendation in Q3 2018
Screen Capture: Candidate Recommendation in Q4 2018
Identifiers for WebRTC Statistics: Candidate Recommendation in Q2 2018, Proposed Recommendation in Q3 2019, Recommendation in Q4 2019
Object-oriented APIs: First Public Working Draft in Q3 2018, Candidate Recommendation in Q2 2019

Coordination

For all specifications, this Working Group will seek horizontal review for accessibility, internationalization, performance, privacy, and security with the relevant Working and Interest Groups, and with the TAG. Invitation for review must be issued during each major standards-track document transition, including FPWD and at least 3 months before CR, and should be issued when major changes occur in a specification.

Additional technical coordination with the following Groups will be made, per the W3C Process Document:

W3C Groups

Web Platform Working Group: The Web Platform Working Group defines a number of markup elements and APIs that serves as the basis on which the RTC APIs have been developed. In addition, all the APIs developed by this group are based on WebIDL which the Web Platform Working Group is specifying.
Devices and Sensors Working Group: The Devices and Sensors Working Group develops APIs to access sensors which have similarities with APIs needed to access media devices. The group was also initially involved in the design of the media capture APIs.
Audio Working Group: The API developed by the Audio Working Group builds upon the MediaStream object built by this group; further collaboration on the management of audio output device is expected.
Web Application Security Working Group: The Web Application Security Working Group is developing guidance on APIs that expose sensitive information, and an API to manage permissions, both of which matter to several of this group specifications.
Second Screen Working Group: The Second Screen Presentation Working Group is developing APIs to allow rendering of media on secondary devices; potential overlap with features enabled by the Audio Output Devices API will need to be looked at.
Web Performance Working Group: The Web Performance Working Group APIs share goals and characteristics with the WebRTC Statistics API.
Media and Entertainment Interest Group: Work on gathering use cases and requirements for Home Networking scenarios within the Media and Entertainment Interest Group may uncover aspects that affect the design of real-time communications functions. The WebRTC Working Group will coordinate with the Interest Group on these use cases and requirements as appropriate.

External Organizations

IETF Applications and Real-Time Area (ART): The RTC APIs developed by this group will build upon the protocols and formats developed in the IETF RTCWeb Working Group. Subsequent to the termination of that WG, this WG will liaise with other groups of the ART area and elsewhere in the IETF as appropriate; of particular interest are the MMUSIC, AVTEXT, ICE and QUIC working groups.
IETF Transport Area Working Group (TSVWG): The TSVWG develops SCTP on which WebRTC data channels relies.

Web Hypertext Application Technology Working Group (WHATWG): The RTC APIs developed by this group will potentially reference the Fetch, Streams and other API specifications maintained by the WHATWG

Participation

To be successful, this Working Group is expected to have 6 or more active participants for its duration, including representatives from the key implementors of this specification, and active Editors and Test Leads for each specification. The Chairs, specification Editors, and Test Leads are expected to contribute half of a working day per week towards the Working Group. There is no minimum requirement for other Participants.

The group encourages questions, comments and issues on its public mailing lists and document repositories, as described in Communication.

The group also welcomes non-Members to contribute technical submissions for consideration upon their agreement to the terms of the W3C Patent Policy.

Communication

Technical discussions for this Working Group are conducted in public: the meeting minutes from teleconference and face-to-face meetings will be archived for public review, and technical discussions and issue tracking will be conducted in a manner that can be both read and written to by the general public. Working Drafts and Editor's Drafts of specifications will be developed on a public repository, and may permit direct public contribution requests. The meetings themselves are not open to public participation, however.

Information about the group (including details about deliverables, issues, actions, status, participants, and meetings) will be available from the WebRTC Working Group home page.

Most WebRTC Working Group teleconferences will focus on discussion of particular specifications, and will be conducted on an as-needed basis.

This group primarily conducts its technical work in its repositories' GitHub issues and on its public mailing list public-webrtc@w3.org (archives). The public is invited to review, discuss and contribute to this work.

The group may use a Member-confidential mailing list for administrative purposes and, at the discretion of the Chairs and members of the group, for member-only discussions in special cases when a participant requests such a discussion.

Decision Policy

This group will seek to make decisions through consensus and due process, per the W3C Process Document (section 3.3). Typically, an editor or other participant makes an initial proposal, which is then refined in discussion with members of the group and other reviewers, and consensus emerges with little formal voting being required.

After mailing list and other informal discussion, substantive change proposals should be submitted as GitHub pull requests. These can come from the editors or from WG members.

Chairs are responsible for determining whether or not there is WG consensus for the changes contained in a pull request.

Editors are responsible for “curating” the pull requests to reject frivolous ones and substantive ones that the Chairs have determined do not comply with the IPR policies.

In cases where the editors make substantive changes without WG consensus, those changes must be labeled as provisional. The chairs are responsible for resolving the status of such changes.

When the Chair puts a question and observes dissent, after due consideration of different opinions, the Chair should record a decision (possibly after a formal vote) and any objections, and move on.

To afford asynchronous decisions and organizational deliberation, any resolution (including publication decisions) taken in a face-to-face meeting or teleconference will be considered provisional. A call for consensus (CfC) will be issued for all resolutions (for example, via email and/or web-based survey), with a response period from one week to 10 working days, depending on the chair's evaluation of the group consensus on the issue. If no objections are raised on the mailing list by the end of the response period, the resolution will be considered to have consensus as a resolution of the Working Group.

All decisions made by the group should be considered resolved unless and until new information becomes available, or unless reopened at the discretion of the Chairs or the Director.

This charter is written in accordance with the W3C Process Document (Section 3.4, Votes), and includes no voting procedures beyond what the Process Document requires.

Patent Policy

This Working Group operates under the W3C Patent Policy (5 February 2004 Version updated 1 August 2017). To promote the widest adoption of Web standards, W3C seeks to issue Recommendations that can be implemented, according to this policy, on a Royalty-Free basis. For more information about disclosure obligations for this group, please see the W3C Patent Policy Implementation.

Licensing

This Working Group will use the W3C Software and Document license for all its deliverables.

About this Charter

This charter has been created according to section 5.2 of the Process Document. In the event of a conflict between this document or the provisions of any charter and the W3C Process, the W3C Process shall take precedence.

Charter History

The following table lists details of all changes from the initial charter, per the W3C Process Document (section 5.2.3):

Charter Period	Start Date	End Date	Changes
Initial Charter	5 May 2011	30 September 2015	N/A
Rechartered	27 July 2015	31 March 2018	This charter reflected the actual split of the various features identified in well-defined specifications, and added WebRTC NV in scope for the group.
Rechartered	@@@	@@@	@@@