Parveen Aggarwal <parveenakara...@gmail.com> writes: > I have below scenario > > 1. A Calls B with "sendrecv" > 2. B holds call with "sendonly" > 3. A holds call with "inactive" -- both A and B media direction is " > *inactive" *now
Let's spell this out more clearly: 1. A offers "sendrecv" to B. B answers "sendrecv". 2. B holds call: B offers "sendonly". A answers "recvonly". 3. A holds call: A offers "sendonly". B answers "inactive". Note that in step 3, A wants to put the call on hold, so it is unwilling to *send* but it is willing to *receive*. However, B is unwilling to send, so it vetoes media in that direction, leaving only "inactive". Note the general principle that you can't describe what is happening by simply saing "X holds call with yyyy", you have to show both the offer and the answer to understand the dynamics of the interaction. > Now, If B receives re-invite without SDP what should be media direction > attribute value > "*sendonly"* or *"inactive" *in offer of 200OK As others have noted, B should offer *everything that it is willing to do*. In this case, B still has the call on hold, so it is willing to do "sendonly", as it is willing to send music-on-hold but isn't willing to render any media that it receives. Since A still has the call on hold, it will likely answer "inactive". > *As per RFC 6337, Section 5.3. Hold and Resume of Media* > > If a UA has occasion to send another offer in the session, without > any desire to change the hold status (e.g., in response to a re- > INVITE without an offer, or when sending a re-INVITE to refresh the > session timer), it should follow the "General Principle for > Constructing Offers and Answers" (Section 5.1). * If it previously* > * initiated a "hold" by sending "a=sendonly" attribute or "a=inactive"* > * attribute, then it should offer that again*. If it had not previously > initiated "hold", then it should offer "a=sendrecv" attribute, even > if it had previously been forced to answer something else. Without > this behavior it is possible to get "stuck on hold" in some cases, > especially when a 3pcc is involved. Note in the passage that you marked, "If it previously initiated a "hold"...". The use of "initiated" means "If it previously *offered* a=sendonly or a=inactive ...". Dale _______________________________________________ Sip-implementors mailing list Sip-implementors@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
