RTCWeb JSEP XMPP/Jingle Mapping

In draft , it is mentioned that there are several options for the signalling mechanisms: ROAP, SIP or XMPP/Jingle. This document focuses on XMPP/Jingle and tries to explain how to use JSEP and XMPP/Jingle to exchange session descriptions.

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 .

The example here shows a typical call setup using the JSEP model. We assume the following architecture in this example, where UA is synonymous with "browser", and JS is synonymous with "web application". In , it shows the overall mapping architecture.

+----------------------+ | Web | | | | Server | +----------------------+ / \ / \ Jingle / \ Jingle / \ / \ / \ +-------------+ +--------------+ | Web | | Web | | Application | | Application | + ----------- + + ------------ + ^ ^ | SDP | SDP | | V (JSEP) V (JSEP) +-------------+ +--------------+ | Caller | | Callee | | | <====== Media =======> | | | Browser | | Browser | +-------------+ +--------------+

To initiate a session, the Caller can send the offer to the Callee by using Jingle "session-initiate" action. CallerJS->CalleeJS: ]]>.

To perform the ICE process, the Caller can exchange the ICE candidates with the Callee by using Jingle "transport-info" action. CallerJS->CalleeJS: ]]>. CalleeJS->CallerJS: ]]>.

If the Callee accepts a session, it can send back the answer by using Jingle "session-accept" action. CalleeJS->CallerJS: ]]>.

To terminate a session, the Caller can send the offer to the Callee by using Jingle "session-terminate" action. CallerJS->CalleeJS: ]]>.

To add media (e.g.video) to an existing session, the Caller can use Jingle "content-add" action. CallerJS->CalleeJS: ]]>.

To modify media (e.g.change audio to video) to an existing session, the Caller can use Jingle "content-modify" action. CallerJS->CalleeJS: ]]>.

To remove media (e.g.video) to an existing session, the Caller can use Jingle "content-remove" action. CallerJS->CalleeJS: ]]>.

If the Callee accepts the "content-add" action to an existing session from the Caller, Callee can send back answer by using Jingle "content-accept" action. CalleeJS->CallerJS: ]]>.

If the Callee rejects the "content-add" action to an existing session from the Caller, Callee can send back answer by using Jingle "content-reject" action. CalleeJS->CallerJS: ]]>.

To send informational hints about parameters related to an existing session, for example, add new video sources to a call that already has video, the Caller can indicate that by using Jingle "description-info" action. CallerJS->CalleeJS: ]]>.

To acknowledge the description information to an existing session from the Caller, Callee can send back answer by using IQ stanza of "result" type. See . CalleeJS->CallerJS: ]]>.

If there are errors occurred during an existing session, the Callee can send back answer by using IQ stanza of "error" type. See . CalleeJS->CallerJS: ]]>.

TBD 1: do we have usage for the following actions: "security-info", "session-info"? TBD 2: do we need to redefine a transport method? If yes, we can use "transport-replace", "transport-accept", "transport-reject".

In , CallerJS uses Jingle "session-initiate" action to initiate a session with CalleeJS, and uses Jingle "transport-info" to exchange ICE candidates with CalleeJS. Then CalleeJS accepts the session using Jingle "session-accept" action. After the media session, CallerJS uses "session-terminate" action to terminate the session, and CalleeJS acknowledges with IQ stanza of "result" type.

| |-------------------------------------->| | | | | |-------------------------------------->| | | | | |<--------------------------------------| | | | | |<--------------------------------------| | | | Media Session | |<=====================================>| | | | | |-------------------------------------->| | | | | |<--------------------------------------| | | ]]> Message details go here...

In , CallerJS uses Jingle "content-add" action to add video media to an existing session. CalleeJS accepts that by using Jingle "content-accept" action. For simplicity, candidate exchange is not shown.

| |-------------------------------------->| | | | | |<--------------------------------------| | | | Media Session | |<=====================================>| | | ]]> Message details go here...

In , CallerJS uses Jingle "description-info" action to add new video sources at the same time to a call that already has video. CalleeJS also uses Jingle "description-info" action to indicate the new sources to the remote side. After that, they uses IQ stanza of "result" type to acknowledge each other.

| |-------------------------------------->| | | | | |<--------------------------------------| | | | | |-------------------------------------->| | | | | |<--------------------------------------| | | | Media Session | |<=====================================>| | | ]]> Message details go here...

TBD.

This document requires no actions from IANA.

The author would like to thank Kiran Kumar and Bert greevenbosch for the reviews and feedbacks.