XMPP protocol extensions already defines a method for initiating peer-to-peer media sessions such as &xep0166; however due to its very nature of being peer-to-peer it does not work very well in scenarios with online meetings. It also does not work alongside offline storage, MUC history and &xep0313;.
-Using a web browser to manually request a URL from an HTTP server and sharing the link has been a workaround for this for a long time now. While users have a variety of services to choose from, the downside of this manual approach is that an XMPP client can not automate this process on behalf of the user since these services don’t share a common API.
-This XEP defines an approach to request initiation of an online meeting via an HTTP server and receive a URL can be used to join and invite others to the meeting.
+XMPP protocol extensions already defines a method for initiating peer-to-peer media sessions such as &xep0166; however due to its very nature of being peer-to-peer it presents a few challenges in scenarios with online meetings that depend on a central Selective Forwarding Unit (SFU) or a Multipoint Control Unit (MCU) to host the meeting..
+Using a web browser to manually request a meeting URL from an HTTP server and sharing the link has been a workaround for this for a long time now. While users have a variety of services to choose from, the downside of this manual approach is that an XMPP client can not automate this process on behalf of the user since these services don’t share a common API.
+This XEP defines an approach to request initiation of an online meeting via an HTTP server and receive a URL can be used to join and invite others to the meeting. It has two main features:
++ The second feature is achieved by using &xep0482;, which describes + call invites using Jingle and external URIs. The XEP mentions how a web URLs can be used as external URI to join a call. For completeness, an example is repeated here to explicitly show how meeting invitations should be sent to invitees. +
++ &xep0482; has other call mangement features, like announcing call join and + leave on the XMPP side. These are relevant for online meetings when the website behind the URL is opened + in a frame or similar inside the XMPP client. The meeting host xmpp client can track meeting participants and know when users leave the meeting without having to depend on APIs provided by the meeting service provider which may present cross-domain challenges. + For completeness, examples are also repeated in this XEP to explicity show their application for online meeting invitations. +
The XMPP server responds with one or two child elements: a 'initiate' element that contains a URL to be used to create and configure the meeting, and an 'invite' element that contains a URL suitable to invite others into the meeting.
+The XMPP server responds with one or two child elements: a 'initiate' element that contains a URL to be used to create and configure the meeting, and an 'invite' element as specified by &xep0482; to invite others into the meeting.
In the URLs that it returns, the server MAY specify a web-based protocol handler if available and registered by the user. Otherwise, standard HTTPS protocol will be specified. In any case, the fully resolved URL provided by the host MUST provide Transport Layer Security (&rfc5246;). The HTTPS URL MUST adhere to &rfc3986;. Non ASCII characters MUST be percent-encoded.
-The XMPP server MAY be tightly integrated with the Meeting Provider and facilitate registration, configuration and association of a web-based protocol handler, but the protocol to implement such integration is out of scope of this document.
@@ -272,25 +302,82 @@ ]]>After the requesting entity has successfully initiated a meeting, it MAY invite other entities to join the meeting. It does so by sending invitees a message stanza containing an 'invite' child element, qualified by the online-meetings namespace, as was sent by the server in response to the initiation request.
-To allow users of clients that do not support this XEP to receive the invitation, a &xep0066; element and/or a 'body' element containing the meeting details MAY be included.
-To allow users of clients that do not support &xep0482; to receive the invitation, a &xep0066; element and/or a 'body' element containing the meeting details MAY be included.
+There is no further XMPP communication required between the server and the requesting entity for participants to join the meeting. The actual online meeting engagement with the provided URL is out of scope of this document.
+ ++ Invitees are sent a message containing an <invite> element in the urn:xmpp:call-invites:0 + namespace. For online meetings, the audio video attributes should default to "true". +
+ The <invite> element contains sub-elements <external> and <meeting> to provide the meeting URL and the identity of the meeting service provider. +
There is no further XMPP communication required between the server and the client for the client to join the meeting. The actual online meeting engagement with the provided URL is out of scope of this document.
-+ A meeting invitation can be retracted by sending a message containing a <retract> element with an 'id' attribute + containing the id of the invite message qualified by the urn:xmpp:call-invites:0 namespace. +
++ A meeting invitation can be accepted by sending a message containing an <accept> element with an 'id' attribute + containing the id of the invite message and qualified by the urn:xmpp:call-invites:0 namespace. + The <external> and <meeting> elements from the invitation are placed in the <accept> element as specified in &xep0482;. +
++ After the <accept> was sent, the accepting client handles the URI. The exact behaviour of opening the URI is implementation specific and can be determined from the type attribute of the <meeting> element. +
++ A meeting invitation can be rejected by sending a message containing a <reject> element with an 'id' attribute + containing the id of the invite message and qualified by the urn:xmpp:call-invites:0 namespace. +
++ When a meeting participant leaves a meeting, it sends a message containing a <left> element with an 'id' attribute + containing the id of the invite message and qualified by the urn:xmpp:call-invites:0 namespace. +
+The server SHOULD choose an appropriate timeout for the validity of the URL. Since there is no reason for a client to wait between requesting the URL and joining the meeting via the URL before dispatching invitations, relatively low timeout values of around 300s are RECOMMENDED.