In simple words we can say all the calls will come to inbound proxy (whose IP is been exposed to external world...) which intern forward the request to the intended user with in its domain...
Bit in hard configured scenarios 2 UAs can communicate directly also... For interoperability reasons, we can consider the calls will always be forwrded through inbound proxy. Thanks & Regards, Nataraju A.B. "Progress has little to do with speed, but much to do with direction" -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Santosh Sahu Sent: Tuesday, July 06, 2004 9:08 PM To: sip mail list Subject: RE: [Sip-implementors] Query on User Agent Hi, The use of proxy is not limited to this. Even if a phone book is used to store the sip addresses. There may be cases where in the target phone is moved to some other location. It needs to get registered with a different proxy of a different service provider first. ( the concept of roaming comes into picture here.) In this case any calls made to the target phone need to go to the redirect server which redirects the request via the proxy server. Regards, santpsh -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Jerry Ipe Thomas Sent: Monday, June 28, 2004 10:02 AM To: Shahed Moolji Cc: SIP Implementors Mailing List Subject: RE: [Sip-implementors] Query on User Agent Hi Shahed, To add to your comments... These hard phones have a facility known as a phone-book call wherein the user can configure the target's phone number (SIP Username), IP address and transport port number in his phone-book so that when he/she dials that particular phone number, he/she will in effect initiate a direct call to the end user agent. So you don't necessarily need a proxy server to make SIP calls. Warm Regards, Jerry Ipe Thomas Engineer(R&D) D-Link India Ltd. Software & R&D Center Bangalore - 68 Ph: +91-80-26788350/1 Extn: 117 Mob: +919886442530 -----Original Message----- From: Shahed Moolji [mailto:[EMAIL PROTECTED] Sent: Friday, June 25, 2004 7:29 PM To: suresh parakkal; [EMAIL PROTECTED] Subject: Re: [Sip-implementors] Query on User Agent Suresh, I am 99.9% sure that there is no need for a proxy server etc. 2 UA's can interact directly. However, some hardware phones insist on first registering with a proxy first, so if you want to say, test your software UA with one of these devices, it may be a problem. Regards Shahed > In other words whether the User agent (phone) will have the capability > to initiate the call as well as receive the call by default as per the SIP > standards? _______________________________________________ Sip-implementors mailing list [EMAIL PROTECTED] http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors _______________________________________________ Sip-implementors mailing list [EMAIL PROTECTED] http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
