Re: [sipcore] Last Call: <draft-ietf-sipcore-status-unwanted-04.txt> (A SIP Response Code for Unwanted Calls) to Proposed Standard

[Pete Resnick <[e-mail]>]

Just on a couple of small points:

On 21 Mar 2017, at 11:59, Adam Roach wrote:

> The problem is that the semantics of 666 are backwards from the 
> semantics of 603.
>
> 603 means "there is an issue with the disposition of the *called* 
> party that prevents completing the call."

That's not how 603 is described in 3261. It can be used to express that 
"the user explicitly does not wish to ... participate." Whether that's 
based on being in the shower or not liking the number in the caller id 
or something else, it expresses the called party's decision not to take 
the call.

> 666 means "there is an issue with the disposition of the *calling* 
> party that prevents completing the call."

That's not how the mechanism is described in this document. It is not 
that you send back 666 when the system determines something about the 
calling party; you send back 666 when the called party says something 
(in this case "SPAM!") that indicates that the called party declined the 
call.

I disagree that the semantics are different.

> ...I think is based on a misperception of how SIP clients actually 
> work when they receive 6xx responses.

I think this is a fair criticism insofar as I agree that either 666 or a 
header on 603 will work equally in today's usage scenarios. My only 
response is that I have rosy glasses looking to future advances that 
might make us regret having painted ourselves into a corner.

pr
-- 
Pete Resnick <http://www.qualcomm.com/~presnick/>
Qualcomm Technologies, Inc. - [phone]