How you choose to mate SIP and MGCP depends a lot on which kind of MGCP gateway you are trying to control, unless you have a really solid understanding of telephony and can generalize it sufficiently to begin with. Neither the line-like or trunk-like endpoint state machines are very SIP-like. But it's a relatively straight-forward project if you understand the protocols.
Most soft switches have call engines that they plug SIP, MGCP, SS7 into. These kind of things can help mediate some of the quirks, and give you a good working point for the future. Part of the challenge with MGCP is that good state machines aren't readily available, as the are with SIP. In my experience it's kind of a trial-by-fire. Another challenge with MGCP is that it means different things to different people, so you should be prepared for devices to deviate if not directly violate a spec. It help if you are designing this with a particular device in mind, so you can point things in the proper direction. MEGACO is a different beast entirely from MGCP. IMO, a SIP to MEGAGO mapping, starting from zip, is really an experts-only affair. Cheers > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf > Of Paulo de Arruda Borelli > Sent: Tuesday, October 25, 2005 5:56 PM > To: [EMAIL PROTECTED]; [email protected] > Subject: RE: [Sip-implementors] SIP/MGCP doubts > > Hi, > > Can you detail a little bit more what you are doing? QoS is > related to media. But SIP and MGCP relate to call signaling. > They do share a common protocol for negotiating the media > part (SDP). But it's not still clear what you really need to do. > > Anyway, in short, the softswitch should have a call processor > layer that will control the SIP Proxy and the MGCP Call > Agent. After receiving an INVITE, the SIP Proxy would tell > the call processor layer that there's a call to be placed. If > this call will be routed to an MGCP endpoint, the call > processor layer will tell the MGCP Call Agent to select an > appropriate channel (which could be selected by a routing > processor inside the softswitch). The MGCP Call Agent would > then send an "Add" to the MGCP endpoint (two "Add's" in fact, > requiring the selection of the desired permanent termination > and also an ephemeral termination (RTP)). > > There are many more details and the above is more suited to > MEGACO, and not exactly MGCP. But they are similar and this > should help. > > Regards > Paulo Borelli. > > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf > Of [EMAIL PROTECTED] > Sent: Tuesday, October 25, 2005 10:32 AM > To: [email protected] > Subject: [Sip-implementors] SIP/MGCP doubts > > Greetings > I'm a SIP/MGCP implementor.I'm a project about VoIP's QoS,and > I have some doubts about the interface SIP/MGCP: > > What kind of messagens(SIP messages) the calls agents exchange? > How SIP messagens are translated to MGCP messages, in the > Call Agent(in IMS context)? > > Many thanks? > > > _______________________________________________ > 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 _______________________________________________ Sip-implementors mailing list [email protected] http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
