I once asked how can you differentiate between the caller and the callee in a call that occurrs in the same SIP agent. That is, the caller is trying to call a user who is available on the same SIP agent (imagine a SIP agent that handles several telephone sets). The problem here is that the call-id, to and from will all be the same. The solution was to simply distinguish between the caller and the callee. That is, there should be one list for callers and one list for callees (or some separation between calls that act as callers and calls that act as callees). My first problem with the solution was that after the ACK, there is no distinction between caller and callee. How can the calls be distinguished now? The solution that I found was that after the ACK, the caller and the callee expect the 'to' and the 'from' to be reversed. However, these solutions do not work well if the SIP is also acting as a proxy. As a proxy, it may receive messages from both the caller and the callee. This makes it difficult for me to put the call in either the 'caller' list or the 'callee' list. Also, after the ACK, the proxy can receive messages with either the 'to' and the 'from' reversed or not. Basically, if the user agent is a proxy, then it cannot do any of these comparisons. Is there a clean solution for this? Currently, the only solution that I found was to mark the proxied calls and put them both on the caller list and on the callee list, and to search for either reversed or regular 'to' and 'from'. -- Dvir Oren <[EMAIL PROTECTED]> Lucid Voice Ltd. <http://www.lucidvoice.com> 5 Jabotinski St., Ramat-Gan, 52520 Israel Tel: 972 3 5757488 Fax: 972 3 5757499 _______________________________________________ Sip-implementors mailing list [EMAIL PROTECTED] http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
