Gateway Call Summary 10/20/98 11AM-1PM EDT Attendees registered for call *********************************** Bellcore, AT&T, Cisco, Nortel, Lucent, Intel, Siemens, Level 3, Ascend, 3COM, IBM, Telia, MCI, NEC, PictureTel, Sun Microsystems, RADVision, Accord, Selsius, Madge, AGCS, IDT/Net2Phone, VTEL, Dialogic, NetSpeak, Delta Information, Ricochet, Trillium Digital Systems, Teleogy Networks, Univ Bremen, Perey Consulting, VideoServer, others Call purpose summary *************************** The goal of the audio call was to identify the work items we need to complete heading into the November Q14 meeting on H.323 Gateways interworking with switched circuit networks. Agreements reached on call ********************************** 1) Interface A is a high priority item. It is a new protocol and the first item of work should be the definition of its scope and requirements. There was agreement that Interface A should be media related and not be associated with call setup. It was agreed that Interface A would deal with the allocation and management of resources used for packet/circuit media conversion (e.g. DSP's for modem, fax, transcoding, etc.) It was agreed to keep the scope of Interface A within the terms of reference outlined in paragraph 3.4.1 of TD89. For example, we are not trying to replace existing H.323 functionality with a new protocol. 2) We will specify the Interworking of H.323 to SS7/ISUP signaling (potentially something similar to Q.699) and the Interworking of H.323 to SCN FAS/NFAS signaling. This work will most likely be contained in an H.246 Annex. 3) We will complete H.246 Annex B - the media conversion of H.323 to voice/voiceband terminals. (e.g. DTMF to UUI, etc.) 4) We agreed to exclude the MC to MP communication definition from the work destined for determination at the next Study Group meeting. Active discussions ********************** 1) What should we do with Interfaces B, C, and D? Given that the messages passing across these interfaces must reflect all of the content of the signaling that the respective signaling functions receive from and send to external entities ... are these protocols modified or extended ISUP for Interface D, modified or extended Q.931 or QSIG for Interface C, and modified or extended H.225 for Interface B? ... or are they a new abstract protocol (ABP) that ISUP, FAS/NFAS, and H.225 are converted to? The proponents of the abstract protocol said it would allow the high level gateway control logic to be shielded from the H.225/FAS-NFAS/ISUP state machines. Others said that too much information would be lost in a conversion between H.225/FAS-NFAS/ISUP and an abstract protocol (ABP) and that the ABP would end up having all of the fields carried on the H.225, FAS-NFAS, and ISUP interfaces. No conclusion was reached for moving forward. Nortel suggested with look at specific call scenarios to drive the requirements of Interfaces B, C, and D. General information ********************** BellCore reported that IPDC and SGCP have merged their protocol proposals as MGCP. MGCP was introduced into the IETF on 10/19 and according to Nortel, a working group is being kicked off in the IETF. There was a discussion on how to get the IETF and ITU-T to work together on these protocols but no conclusion was reached. MGCP information will be posted to the ITU reflector. Next meeting *************** I would like to invite you to participate in an audio call, Tuesday November 3rd from 11AM to 1PM EST to discuss our continued work plan for gateway decomposition. Please send bridge port requests directly to me (mreid@videoserver.com) by Monday November 2nd at 12:00 Noon EST so that I can make the proper arrangements. I will send port assignments later that day. All comments on this summary are welcome! Mark