Valentin Nechayev wrote:
>>>>>> Paul Kyzivat <[EMAIL PROTECTED]> wrote:
>
>>>> Is it ""normal""? Why the hell does a softswitch require *anything* in
>>>> the "To" URI? (except the To_tag XD).
>>> Even if you found that this wasn't correctly detected, generally
>>> it is quite normal to check and use username in h_To as something
>>> another than username in RURI. It can be used, for example, to
>>> select specific DID number across the pool assigned to the
>>> customer specified in RURI (this is used e.g. in Sipura/Linksys
>>> SPA9000 as one possible form of such DID specification). See also
>>> ISUP specs and draft-yu-tel-url: they specify special "routing
>>> number" which also can be passed, in different tradition, in RURI
>>> (while final number is passed in h_To).
>> Yes, it isn't unusual to see that done. And it is BROKEN!
>> That algorithm breaks any time a call is forwarded.
>
> What do you mean here for "forwarded"?
> If forward as proxy according to rules in chapter 16 - proxy
> doesn't change h_To.url.username. If some another kind of forward
> (e.g. via B2BUA) its agent is usually aware of this difference.
Right. Lets take an example:
Assume call is initially To: sip:[EMAIL PROTECTED]
Alice forwards it to sip:[EMAIL PROTECTED] by putting that into the R-URI.
(To URI is unchanged.)
The call then arrives at the softswitch for biloxy.com. The softswitch
then rewrites the R-URI with the contact for Bob's device:
sip:bobphone.biloxy.com.
When the invite reaches the phone, it tries to use the To-uri to figure
out which line the call was addressed to. But it is expecting it to be
either sip:[EMAIL PROTECTED] or sip:[EMAIL PROTECTED] It is not
expecting sip:[EMAIL PROTECTED] and so can't figure out which line was
intended.
Paul
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