Graham Francis : The SIP School
Graham Francis
| The SIP Blog is just that; with opinion and analysis on all things SIP in the world of VoIP

The SIP Protocol

Hitch Hikers guide to SIP

August 5, 2008

Ok, this is an old (2006) but great doc that you should have a look at if you want to get to grips will all the relevant RFCs related to SIP.  Written by Jonathan Rosenburg and posted here  ... Download it and have a read, it will save you a lot of time by stopping you reading RFCs that are no longer relevant or have been replaced.  Though keep an eye out for new drafts on the IETF website as things are always changing.

SIP/SIMPLE v XMPP debate rumbles on

August 8, 2008

So you are looking for a winner of the Instant Messaging protocol debate are you?  Well, keep looking and maybe it will become clear over the coming years because XMPP has just gained another supporter, Yahoo. See this article on CNET.  We think this is good for interoperability between other XMPP based services as no translation services would be needed - so Google Talk (also based on XMPP) should 'in theory' interoprate with whatever Yahoo! do.  So far so good.

But what about SIP/SIMPLE?  Well the IMPP working group came up with a Spec/Set of rules/whatever you want to call it (the CPP actually) that defines how IM protocols should map to each other so that 'islands' of IM systems don't have to stay as islands and SIP/SIMPLE / XMPP systems can interoperate - just see what Jabber are up to to clarify this.

So is SIP/SIMPLE doomed because Yahoo and Google may end up on each others buddy list?  Well no, due to the fact that every Telecoms manufacturer I can think of (Mitel, Siemens, Nortel, Panasonic, Avaya etc. etc.) all use this protocol in their Unified Comms/Messaging products and are unlikely to switch.

So for now, no winners just two big players who should play nicely together (Hopefully).





SIP, a reality check

July 13, 2009

If you and your company are involved in Voice over IP and Unified Communications then there's no doubt you'll have heard about SIP (the Session Initiation Protocol).  You may be (even a little bit) excited about all the things it promises to achieve by enabling multivendor products and services to work together.  However, sometimes it's good and even necessary to just stop and look closely at what's actually happening with SIP, who's using it and what lies ahead for this most disruptive of protocols! 

So let's start by asking,

What is SIP?

Well, SIP is boring!



Ok, to me it's not boring. However to people who simply want to make phone calls and use IM or their Unified Communications client to 'reduce human latency' (yes, that's a real UC benefit) it's not really something they care about.  Who wants to talk about signalling protocols, new SIP methods and the work of the IETF working groups?  Not your customers that's for sure - all they want to know is will it work, how much and will it save them money?