Vijay,
Thanks for u'r answers. I was also thinking same, my only doubt was since
the Route in Preconfigured should it be overriden after receiving on
reception of 2xx response or not?. From u'r reply now i am sure it will.

i was thinking in the following way, can u pl. comment if my interpretation
is correct or not:-

1. IN CASE OF ACK to 2xx-Response:
Since ACK is sent in response to 200-OK, so its Route will be affected by
the Record-Route of 200-OK, i.e Route in ACK will depend on the Value of
Record-Route in 200-OK.

2. IN CASE OF ACK to non-2xx Response:
The non-2xx-Reponse doesn't contain any R-R header. Since the non-2xx final
Reponse has nor R-R, so the Route set will be Empty and hence the ACK sent
in response to a non-2xx-Reponse, will have null/empty Route header, i mean
the Route Header will not present in ACK in this case.

3. IN CASE OF CANCEL:
Since CANCEL is sent to CANCEL the original REQUEST(in this case INVITE), so
its Route will not be affected by the Record-Route of 18x-Response, i.e
Route in ACK will NOT depend on the Value of Record-Route in 18x-Response,
RATHER its value will be same as the Route value in original REQ being
CANCELLED,i.e same value as in INVITE in this case.

Also still my 1st 3 doubts are un-answered. So can somebody pl. help me out.

Regards,
Manoj
-----Original Message-----
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED]]On Behalf Of Vijay Kamath
Sent: Tuesday, October 15, 2002 11:17 PM
To: manoj mallik
Cc: Vijay K. Gurbani; [EMAIL PROTECTED]; AJIT KATANKOT
Subject: Re: [Sip-implementors] Preconfigured route


Inline.

manoj mallik wrote:

>Well this again raises couple of doubts in my mind, as described below;
>In case of Preconfigured route:-
>1. The Route should contain the URI of next Hop or remote target or any one
>of these two? what is actually recommended?
>2. What should the behavior of the Proxy if Route header in INVITE is set
to
>next Hop(which is the address of the Proxy itself)
>3. What should be the behavior of the Proxy if Route header in INVITE is
set
>to remote target or some other address?
>4.Lets consider the call is between:
>       UserA---Proxy---UserB
>UserA send a INVITE with preconfigured Route. so lets say the INVITE will
>contain the Route header that contains the address of next Hop(i.e of
>Proxy). But the Proxy doesn't want to see all messaging thru out the call,
>So the proxy doesn't include Record-Route in INVITE while sending it to the
>dest. UA(i.e to User B).
>So as consequence, there will be no Record-Route in 18x and 200 Response
>from User B.
>Now my doubt is
>       i. will this ACK,will Contain Route Header or not? if yes, then what will
>be its Value? will     be same as that present in INVITE or there will be no
>Route in ACK in this case??
>
ACK will not contain Route header, since the routeset that UserA creates
on reception of 2xx would be empty.

>       ii. the ACK which be sent to UserB directly from UserA or thru the proxy
>
ACK will be sent directly to UserB.

>
>5. The following doubt is related to when there are multiple proxies are
>involved in the call:-
>Lets consider the call is between:
>       UserA---Proxy1---Proxy2---UserB
>In the above scenario, UserA includes a Route header(case-1:Route contains
>only pxy1-ipaddr, case-2: Route contains both pxy1 and pxy2 ipaddr) in
>initial INVITE. This time PXY-2 inserts Record-Route in INVITE where as
>PXY-1 doesn't. So PXY-2 will see all messages thru out the call and hence
>there will be Record-Route in 18x and 200-OK messages which is the address
>inserted by PXY-2.
>
>Now my doubt is
>       i. In ACK, what will be the value of the Route header? will be same as
that
>present in INVITE      or as the Record-Route value received in 200-OK??
>
In this case, the routeset would have one element i.e PXY-2. There will
be a single Route header. What it contains depends on whether PXY-2 is a
loose/strict router. If PXY-2 is a loose router, then Route header would
be the uri of PXY-2 itself. If PXY-2 is a strict router, then Route
header would be the uri of UserB.

>       ii. So in this case, the ACK which be sent directly to PXY-2 from User A
or
>to the PXY-1
>
ACK would be sent to PXY-2.

>
>Can somebody throw lights on these above queries w.r.t strict and loose
>routing as well.
>Thank you all.
>Regards,
>Manoj
>
>
>
>



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