I agree.  There seems to be an inconsistency between the statement below
from 17.2.1 and Figure 7, which indicates that only 101-199 are handled
by server transaction in "Proceeding" state.

"The TU passes any number of *provisional responses* to the server
transaction.  So long as the server transaction is in the "Proceeding"
state, each of these MUST be passed to the transport layer for
transmission"

-Ramakrishna

-----Original Message-----
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of Jeroen
van Bemmel
Sent: Friday, October 14, 2005 12:07 PM
To: Paul Kyzivat; Martin Koenig
Cc: [email protected]
Subject: Re: [Sip-implementors] 100 trying

Paul,

I found several things in RFC3261 that made me wonder as well:
- INVITE server transaction (Figure 7): responses 101-199 from TU are to
be sent, what happens to 100?
- What happens if a retransmitted INVITE arrives within 200ms and the
application has not yet sent a 100?

I think an application (TU) should not send a 100 trying twice. What
could happen, is that 100 is the last response sent, so when a
retransmitted INVITE arrives the 100 is repeated.

A reason for sending multiple 100 trying could be to account for packet
loss on an unreliable transport. However, it's probably better to rely
on the sender to retransmit its INVITE for this purpose. So IMO an
application SHOULD NOT send more than one 100 trying

Regards,

Jeroen

----- Original Message -----
From: "Paul Kyzivat" <[EMAIL PROTECTED]>
To: "Martin Koenig" <[EMAIL PROTECTED]>
Cc: <[email protected]>
Sent: Friday, October 14, 2005 12:30 AM
Subject: Re: [Sip-implementors] 100 trying


> Why would you think it is *not* ok?
>
> Paul
>
> Martin Koenig wrote:
>> Hello all,
>>
>> is it legal per RFC3261 to send two separate "100 trying" provisional
>> responses for a SIP Request?
>>
>> A B
>> INVITE ------>
>> <----- 100 trying
>> <----- 100 trying
>> <----- (180 ringing)
>> <----- 200 ok
>> etc.
>>
>> A B
>> REGISTER ------>
>> <------ 100 trying
>> <------ 100 trying
>> <------ 200 ok
>> etc.
>>
>> With best regards,
>> Martin
>>
>> _______________________________________________
>> Sip-implementors mailing list
>> [email protected]
>> http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
>>
> _______________________________________________
> Sip-implementors mailing list
> [email protected]
> http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors

_______________________________________________
Sip-implementors mailing list
[email protected]
http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors



Confidentiality Notice

The information contained in this electronic message and any attachments to 
this message are intended
for the exclusive use of the addressee(s) and may contain confidential or 
privileged information. If
you are not the intended recipient, please notify the sender at Wipro or [EMAIL 
PROTECTED] immediately
and destroy all copies of this message and any attachments.

_______________________________________________
Sip-implementors mailing list
[email protected]
http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors

Reply via email to