Re: Any comparison Study on MGCP vs H.323, MGCP vs SIP
Sez "Masataka Ohta" [EMAIL PROTECTED] H.323 is defined for a LAN environment, not for telephone lines. For telephony people, the IP protocol is for a LAN environment that there is no difference between H.323, SIP, TELNET, or DNS for that matter. "Telephony people" are not relevant here, since we're talking about VoIP. As I said: For VoIP over telephony networks Your statements don't make sense; "VoIP over telephony networks" is an oxymoron, since VoIP is, by definition, over an IP network. some protocol is necessary between two telephony networks. FYI, there is a protocol called TBGP proposed in IETF for the purpose. TBGP is the proposed method for binding E.164 numbers to telephony domains, much like DNS binds names to IP addresses. One would still use SIP (or equivalent) to actually complete the call. If you want to use ITU protocols, please choose some other numbers. So, you are saying SGCP/MGCP are wrong to use 323. Fine. No, he's suggesting that if you wish to use an ITU protocol, H.323 is not the correct one. Perhaps Q.931? FYI, in my design of "The Simple Internet Phone": If you are interested in Internet telephony, see you at INET'2000 in Yokohama for the presentation of our paper "The Simple Internet Phone". Please let us know the URL where you'll be publishing this paper, as some of us may not be inclined to fly to Yokohama to hear about yet another non-standard, proprietary telephony protocol. I chose to keep using 164 (sorry, not 42) at least for the time being, because it is the easiest way to let subscribers replace telephony network with the Internet. MGCP/SGCP/Megaco directly use E.164 numbers. SIP allows users to see only E.164 numbers during a transition period, though it becomes much more pwoerful when you move to a more expressive namespace. [from a prior message] As I pointed it out with regard to iMODE and WAP, an attempt to promote protocols like SIP, a NAT friendly protocol even more complex than H.323 SIP may or may not be NAT-friendly, a point which is best left to other (time-wasting) threads. I would love to see any explanation of how SIP is more complex than H.323; maybe you have them backwards? was based on a wrong strategy destroying the Internet into a collection of mostly-non-IP networks connected by application/transport gateways with mostly-non-IETF application/transport protocols. SIP is not, as you state, based on a strategy of building non-IP networks and connecting them with non-IETF protocols; in fact, it's quite the opposite. SIP allows the replacement of non-IP (ie. legacy telephony) networks and non-IETF (ie. ITU) protocols; in the ideal SIP world, legacy telephony would cease to exist. While a bit dated, Henning Schulzrinne and Jonathan Rosenberg's paper has quite a bit of detail on the subject: http://www.cs.columbia.edu/~hgs/papers/Schu9807_Comparison.ps.gz Masataka Ohta S | | Stephen Sprunk, K5SSS, CCIE #3723 :|::|:Network Consulting Engineer, NSA :|||: :|||: 14875 Landmark Blvd #400; Dallas, TX .:|||:..:|||:.Email: [EMAIL PROTECTED]
Re: Any comparison Study on MGCP vs H.323, MGCP vs SIP
speaking of telephony/telecom protocols, are there any "voice subscriber" MIBs/models - SNMP or CMIP oriented. I'm just looking for a model used for voice subscribers who are provisioned w/ some combination of AAL2, VOIP, GR-303, V.52. Thanks - gaylord
Re: Any comparison Study on MGCP vs H.323, MGCP vs SIP
http://www.cs.columbia.edu/sip has a FAQ addressing this topic.
Re: Any comparison Study on MGCP vs H.323, MGCP vs SIP
Harald; At 09:19 13.05.2000 +0859, Masataka Ohta wrote: For VoIP over telephony networks (that is, mostly over non-Internet networks), H.323 and SS7 are the protocols to choose, because they are defined by ITU-T. H.323 is defined for a LAN environment, not for telephone lines. For telephony people, the IP protocol is for a LAN environment that there is no difference between H.323, SIP, TELNET, or DNS for that matter. SS7 is not a protocol accessible to the subscriber. So? As I said: For VoIP over telephony networks some protocol is necessary between two telephony networks. FYI, there is a protocol called TBGP proposed in IETF for the purpose. If you want to use ITU protocols, please choose some other numbers. So, you are saying SGCP/MGCP are wrong to use 323. Fine. FYI, in my design of "The Simple Internet Phone": If you are interested in Internet telephony, see you at INET'2000 in Yokohama for the presentation of our paper "The Simple Internet Phone". I chose to keep using 164 (sorry, not 42) at least for the time being, because it is the easiest way to let subscribers replace telephony network with the Internet. Masataka Ohta
RE: Any comparison Study on MGCP vs H.323, MGCP vs SIP
From the SGCP FAQ (http://www.argreenhouse.com/sgcp/sgcp-faq.shtml) written two years ago: Do you intend to replace H.323 ? Definitely not. Just look at the picture above, which shows the relaying of a call between an SGCP controlled gateway and an H.323 agent. The combination of gateways plus call agent forms a distributed H.323 system, which is perfectly conforming to the H.323 standard... If not H.323, why not SIP, then? In fact, when we realized that we could not use H.323 between the call agent and the gateways, we tried to base the design of SGCP on SIP. But we stumbled on the fact that SIP is a peer to peer protocol, while we needed a master slave protocol. However, interworking between SIP and SGCP is very easy... (SGCP is one of the ancestors of MGCP.) -- Christian Huitema -Original Message- From: Yixin Zhu [mailto:[EMAIL PROTECTED]] Sent: Thursday, May 11, 2000 7:55 AM To: [EMAIL PROTECTED] Subject: Any comparison Study on MGCP vs H.323, MGCP vs SIP Hi, There are studies on the comparision of the two competing protocol SIP and H.323. However, MGCP can also provide call control functionalities. A network with MGCP only (Call agent, MG etc) can provide basic VoIP service too. Then my questions are 1. Are there any comparison study between MGCP and H.323? 2. Are there any comparision study between MGCP and SIP? You help is very much appreciated. Thanks, Yixin (James) ZHU
RE: Any comparison Study on MGCP vs H.323, MGCP vs SIP
Yes, I need this comparison too, please help. Hubert Chang -Original Message- From: Yixin Zhu To: [EMAIL PROTECTED] Sent: 5/11/00 10:55 AM Subject: Any comparison Study on MGCP vs H.323, MGCP vs SIP Hi, There are studies on the comparision of the two competing protocol SIP and H.323. However, MGCP can also provide call control functionalities. A network with MGCP only (Call agent, MG etc) can provide basic VoIP service too. Then my questions are 1. Are there any comparison study between MGCP and H.323? 2. Are there any comparision study between MGCP and SIP? You help is very much appreciated. Thanks, Yixin (James) ZHU
