Now, since you are getting your basics right, lets move a step further. What really is VoIP (Voice Over IP Protocol) about? Why you need to look at VoIP option when you have traditional telephony?
The main competing protocols are SIP, H.323, MGCP and others include MEGACO, H.248 and proprietary standards from industry leaders and implementors.
A good overview of the VOIP protocols could be found at http://www.protocols.com/pbook/VoIPFamily.htm
There are numerous sites that offer information on these protocols. Some of the important ones include http://www.packetizer.com , Henning Schulzrinne's site http://www.cs.columbia.edu/~hgs , http://www.voip-info.org, http://www.voiponline.com, http://www.voip-jobs.com,
SIP specific sites (Base RFC 3261):
http://www.sipknowledge.com
http://www.sipcenter.com
http://www.tech-invite.com (A very good graphical representation of SIP call flows)
http://www.sipsak.org (SIP Swiss Army Knife -useful tool)
http://sipp.sourceforge.net (Open source test tool/traffic generator)
H.323 (It is a family of protocols which includes protocols like H.225, H.245, T.38, etc):
http://www.packetizer.com/ipmc/h323 (Excellent resource for all things H.323)
http://www.openh323.org/standards.html (Open H.323 is an open-source implementation of H.323 protocol suite and is used widely)
MGCP (Base RFCs - RFC 2705, RFC 3435):
http://www.packetizer.com/ipmc/mgcp
A couple of H.323 sites
ReplyDeletehttp://www.h323forum.org/papers
http://www.javvin.com/protocolH323.html