{"action":"created","issue":{"url":"https://api.github.com/repos/rtcweb-wg/jsep/issues/162","repository_url":"https://api.github.com/repos/rtcweb-wg/jsep","labels_url":"https://api.github.com/repos/rtcweb-wg/jsep/issues/162/labels{/name}","comments_url":"https://api.github.com/repos/rtcweb-wg/jsep/issues/162/comments","events_url":"https://api.github.com/repos/rtcweb-wg/jsep/issues/162/events","html_url":"https://github.com/rtcweb-wg/jsep/issues/162","id":89306249,"number":162,"title":"LipSync groups violating RFC5888","user":{"login":"gloinul","id":11295323,"avatar_url":"https://avatars.githubusercontent.com/u/11295323?v=3","gravatar_id":"","url":"https://api.github.com/users/gloinul","html_url":"https://github.com/gloinul","followers_url":"https://api.github.com/users/gloinul/followers","following_url":"https://api.github.com/users/gloinul/following{/other_user}","gists_url":"https://api.github.com/users/gloinul/gists{/gist_id}","starred_url":"https://api.github.com/users/gloinul/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/gloinul/subscriptions","organizations_url":"https://api.github.com/users/gloinul/orgs","repos_url":"https://api.github.com/users/gloinul/repos","events_url":"https://api.github.com/users/gloinul/events{/privacy}","received_events_url":"https://api.github.com/users/gloinul/received_events","type":"User","site_admin":false},"labels":[{"url":"https://api.github.com/repos/rtcweb-wg/jsep/labels/in%20progress","name":"in progress","color":"ededed"}],"state":"open","locked":false,"assignee":{"login":"juberti","id":1821693,"avatar_url":"https://avatars.githubusercontent.com/u/1821693?v=3","gravatar_id":"","url":"https://api.github.com/users/juberti","html_url":"https://github.com/juberti","followers_url":"https://api.github.com/users/juberti/followers","following_url":"https://api.github.com/users/juberti/following{/other_user}","gists_url":"https://api.github.com/users/juberti/gists{/gist_id}","starred_url":"https://api.github.com/users/juberti/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/juberti/subscriptions","organizations_url":"https://api.github.com/users/juberti/orgs","repos_url":"https://api.github.com/users/juberti/repos","events_url":"https://api.github.com/users/juberti/events{/privacy}","received_events_url":"https://api.github.com/users/juberti/received_events","type":"User","site_admin":false},"milestone":null,"comments":10,"created_at":"2015-06-18T14:19:50Z","updated_at":"2016-04-15T16:57:00Z","closed_at":null,"body":"I. Section 5.3.1:\r\n\r\n   The next step is to generate lip sync groups as defined in [RFC5888],\r\n   Section 7.  For each MediaStream with more than one MediaStreamTrack,\r\n   a group of type \"LS\" MUST be added that contains the mid values for\r\n   each MediaStreamTrack in that MediaStream.  In some cases this may\r\n   result in adding a mid to a given LS group that was not in that LS\r\n   group in the associated offer.  Although this is not allowed by\r\n   [RFC5888], it is allowed when implementing this specification.\r\n\r\n\r\nSo, do I understand it correctly the violation this paragraph is discussing is the following from Section 9.2 of RFC5888:\r\n\r\n   The\r\n   identification-tags contained in this \"a=group\" line MUST be the same\r\n   as those received in the offer, or a subset of them (zero\r\n   identification-tags is a valid subset).\r\n\r\nSo when will these violations occur for a LS group in JSEP. I assume due to that offer and answer has different structure of how MediaStreams uses the different m= lines. But, isn't this just another case of when an answerer will have to do an follow up Offer to be able to add all the MediaStreamTracks and their MediaStreams due to different sets on the two peers?\r\n\r\nI don't really think this specification should override RFC 5888. The obvious solution is to make a new offer by the answering part who couldn't express its desired configuration in the first round."},"comment":{"url":"https://api.github.com/repos/rtcweb-wg/jsep/issues/comments/210546018","html_url":"https://github.com/rtcweb-wg/jsep/issues/162#issuecomment-210546018","issue_url":"https://api.github.com/repos/rtcweb-wg/jsep/issues/162","id":210546018,"user":{"login":"juberti","id":1821693,"avatar_url":"https://avatars.githubusercontent.com/u/1821693?v=3","gravatar_id":"","url":"https://api.github.com/users/juberti","html_url":"https://github.com/juberti","followers_url":"https://api.github.com/users/juberti/followers","following_url":"https://api.github.com/users/juberti/following{/other_user}","gists_url":"https://api.github.com/users/juberti/gists{/gist_id}","starred_url":"https://api.github.com/users/juberti/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/juberti/subscriptions","organizations_url":"https://api.github.com/users/juberti/orgs","repos_url":"https://api.github.com/users/juberti/repos","events_url":"https://api.github.com/users/juberti/events{/privacy}","received_events_url":"https://api.github.com/users/juberti/received_events","type":"User","site_admin":false},"created_at":"2016-04-15T16:57:00Z","updated_at":"2016-04-15T16:57:00Z","body":"I was planning to take a shot at this now that the transceiver stuff has landed."}}