Comment by fenesiistvan

11 years ago

Can anybody tell me, why the SIP chat protocol is so under used?

https://www.ietf.org/rfc/rfc3428.txt

-based on open standards (SIP)

-supported by most VoIP servers (so we have full interoperability between vendors such as Cisco, Huawei, Siemens, Voipswitch, Mizutech, Jitsi and others)

-simple and extendable

-lots of free services, free/open source software. You can also host your own or integrate into your company PBX

In the previous years, we always see the same path for messaging applications:

1. Startup company add messaging based on open standards (SIP/IRC/XMPP/other?)

2. One the company has significant user base, switches to a non-standard / proprietary protocol

Already happened for Skype, Yahoo, Google, Facebook

3 comments

fenesiistvan

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zmb_  11 years ago

>-simple and extendable

It's the first time I hear anyone describe SIP as "simple". If you printed out all the SIP specs, you'd probably have a pile close to a meter high. Among the protocol crowd (including IETFers) SIP is often regarded as an example of protocol design having gone off the rails in a spectacular fashion. It has been repeatedly beat in the market by proprietary protocols that do things better (e.g., see the mess SIP NAT traversal ended up as compared to Skype).

  • fenesiistvan  11 years ago

    Yes, the SIP protocol is not so simple. However a lot of well working implementations already exists (source code, libraries, ready to use software). The core messaging in SIP (RFC 3428) is extremely simple to add as it is just a single method (MESSAGE).

    Adding presence and other funny things with the SIMPLE protocol family is another subject. (However the basic presence is also very simple ...the complications comes when you wish to add file transfer and other fancy things).

    But these can be used as an extra so at least the for chat you are fully interoperable with all other vendors.

zamalek  11 years ago

I've heard from people who have tried to implement it: SIMPLE (3428) is anything but simple. It is a very good example of "enterprise design." In addition, as soon as you start extending the protocol there is a very good chance that your implementation will no longer be interoperable. Take Lync (Microsoft's implementation of SIMPLE) as an example: due to the presence of custom extensions, clients have to implement specific support for it - the protocol doesn't gracefully degrade like XMPP does.

Basically, XMPP came first (first foot in the door) and is a significantly superior protocol due to its simplicity.