Re: [sipcore] #27: Functionality of "Supported: histinfo" is not clear

"Elwell, John" <john.elwell@siemens-enterprise.com> Fri, 03 September 2010 06:46 UTC

From: "Elwell, John" <john.elwell@siemens-enterprise.com>
To: "Worley, Dale R (Dale)" <dworley@avaya.com>
Date: Fri, 03 Sep 2010 08:47:11 +0200
Thread-Topic: [sipcore] #27: Functionality of "Supported: histinfo" is not clear
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Cc: "sipcore@ietf.org" <sipcore@ietf.org>
Subject: Re: [sipcore] #27: Functionality of "Supported: histinfo" is not clear
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This raises the question whether the option tag is needed at all. What harm would be done by removing the option tag?

John 

> -----Original Message-----
> From: Worley, Dale R (Dale) [mailto:dworley@avaya.com] 
> Sent: 03 September 2010 02:05
> To: Elwell, John
> Cc: sipcore@ietf.org
> Subject: RE: [sipcore] #27: Functionality of "Supported: 
> histinfo" is not clear
> 
> ________________________________________
> From: sipcore-bounces@ietf.org [sipcore-bounces@ietf.org] On 
> Behalf Of Elwell, John [john.elwell@siemens-enterprise.com]
> 
> My understanding is that the presence of Supported: histinfo 
> triggers the UAS to send back H-I in the response. The issue 
> that Dale raises makes me wonder whether H-I should 
> unconditionally be echoed in the response, since proxies and 
> B2BUAs might find a use for it, even if the UAC does not 
> request it. A UAC that does not support H-I would just ignore 
> the header field anyway.
> _______________________________________________
> 
> Indeed, and you've reminded me that a proxy that receives H-I 
> in a response may well integrate it into the H-I of the 
> corresponding request and send that in further forks of the 
> request.  So I think we're pretty well demonstrating that 
> even if the UAC doesn't understand H-I, other elements may be 
> using it to pass information to each other.
> 
> Dale
>

[sipcore] #27: Functionality of "Supported: histi… sipcore issue tracker
Re: [sipcore] #27: Functionality of "Supported: h… Elwell, John
Re: [sipcore] #27: Functionality of "Supported: h… Worley, Dale R (Dale)
Re: [sipcore] #27: Functionality of "Supported: h… Mary Barnes
Re: [sipcore] #27: Functionality of "Supported: h… Worley, Dale R (Dale)
Re: [sipcore] #27: Functionality of "Supported: h… Elwell, John
Re: [sipcore] #27: Functionality of "Supported: h… Shida Schubert
Re: [sipcore] #27: Functionality of "Supported: h… Worley, Dale R (Dale)
Re: [sipcore] #27: Functionality of "Supported: h… Mary Barnes