B2BUAs have often caused much confusion because they can be used in a variety of situations. One can make a B2BUA that sits in the middle of a service and exerts control as you describe. I do hope that no one would be so foolish as to actually do this, because it breaks end to end security, increases the probability of failure, and decreases the range of services that could be provided. There are more reasonable ways to make sure theft of service is not possible.
On the other hand, B2BUAs can be media relays. They don't have to be, but they can be. With a B2BUA, one side of it is a UAS and the other side is a UAC, so when you state that media goes between a UAS and a UAC, a B2BUA could very well be in both media paths. However, a B2BUA could choose to copy the SDP from one side to the other, and thus not be in the media path. A session border controller is often implemented as a media relay B2BUA. Brian -----Original Message----- From: Ramachandran Iyer [mailto:[EMAIL PROTECTED] Sent: Tuesday, November 25, 2003 4:56 AM To: KANUMURI Sreeram; [EMAIL PROTECTED] Cc: Adam Roach; [EMAIL PROTECTED] Subject: Re: [Sip-implementors] Question on B2BUA B2BUA will act from from a signalling stand-point,where it isolates both the end (or legs) making it 2 different calls (as opposed to a single call when you would have a proxy in the middle). The major signifcance of having a B2BUA is of control over both parties or both sides of the communication, where is no chance of the B2BUA being elimated from the session path. This helps in it being positioned for all of application/services and becomes a central point for doing billing etc.. Having said that, to reply to your question: RTP will always be between the UAC & UAS, there is no role (no need) for B2BUA to be anywhere there. The SDP information is anyways propagated from one end to the other by B2BUA. Hope this helps. Rama KANUMURI Sreeram <[EMAIL PROTECTED]> wrote: Hi all, In B2BUA will all the RTP packets also route through B2BUA? if yes can you please give a pointer for this.(draft..) if not what is the difference than between Proxy and B2BUA!!! Thanking you in advance!!! Regards, Sreeram _______________________________________________ Sip-implementors mailing list [EMAIL PROTECTED] http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors Do you Yahoo!? Free Pop-Up Blocker - Get it now _______________________________________________ Sip-implementors mailing list [EMAIL PROTECTED] http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
