Subject: [Sipping] About the ECMA TR/87 (aka SIP CTI Interface)

From: Mariano Stokle <[email-masked]>
Date: Fri, 28 Oct 2005 12:25:57 -0300

Recently I noticed the implementation of TR/87 spec in several SIP
Application Servers. My question (sorry it is out off topic for these
lists) is about if it is a right use of SIP according to the
architectural design principles of SIP and particulary, the use of
INVITE for establish a signalling session. I mean: is SIP the right
choice to transport another signalling protocol as CSTA? If yes, it is
INVITE the right method to transport CSTA information or
SUBSCRIBE-NOTIFY would be a better choice? Finally, do we need CSTA
over SIP when we have RFC 4117 for 3PCC?

Regards,

--
Mariano Stokle

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---

From: Frank Derks <[email-masked]>
Date: Mon, 31 Oct 2005 09:02:26 +0100

Hi Mariano,

I realise that I am treading on dangerous ground here, but I couldn't 
resist answering. 

If you are asking yourself whether SIP is appropriate for carrying another 
"signalling 
protocol" is like asking "can I use SIP to do something for me". Most, if 
not all, 
SIP implementations rely on the fact that some other protocol is being 
carried in a SIP
body. SDP and the XML used for IM and presence are good examples of this. 
The SIP methods
that could be used to convey these protocols, is obviously open for 
discussion, but I
fear that it will be extremely difficult to come to real consensus on 
this. In the CSTA
case, I would say that, depending on what you are doing, both methods 
could be appropriate. 

BTW, Microsoft uses SIP messages with the CSTA XML variant for LCS.

3PCC is not quite as powerful as CSTA. Realise that "CSTA" covers a 
complete suite of 3rd
party call control functionality, whereas 3PCC "just" describes a method 
by which a few
3rd party call control services could be realised. Precisely because of 
3PCC's limitations
TR/87 was created.

Cheers,

Frank

Mariano Stokle <[email-masked]> 
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[email-masked]
2005-10-28 12:25 PM

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Subject
[Sip] About the ECMA TR/87 (aka SIP CTI Interface)
Classification

Regards,

--
Mariano Stokle

_______________________________________________
Sip mailing list  https://www1.ietf.org/mailman/listinfo/sip
This list is for NEW development of the core SIP Protocol
Use [email-masked] for questions on current sip
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