24 Jul 2012 09:18
Why do we need prack request
vikram <vikram.hirehal <at> globaledgesoft.com>
2012-07-24 07:18:34 GMT
2012-07-24 07:18:34 GMT
-- --
24 Jul 2012 16:14
Re: Why do we need prack request
Ozdogru, Kutay <kozdogru <at> lgi.com>
2012-07-24 14:14:10 GMT
2012-07-24 14:14:10 GMT
Hi, I advise you to read RFC3262 ( provisional response / reliability) for detailed instructions. Indeed, it is act like ACK SIP method but there are several differences. It is like ACK because provides reliability for provisional responses like (1XX) but also it is like a normal SIP message since it has its own response.( 200 OK ). Regards, Kutay -----Original Message----- From: sip-implementors-bounces <at> lists.cs.columbia.edu [mailto:sip-implementors-bounces <at> lists.cs.columbia.edu] On Behalf Of vikram Sent: 24 July 2012 09:19 To: sip-implementors <at> lists.cs.columbia.edu Subject: [Sip-implementors] Why do we need prack request -- -- _______________________________________________ Sip-implementors mailing list Sip-implementors <at> lists.cs.columbia.edu https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
25 Jul 2012 16:34
Re: Why do we need prack request
Paul Kyzivat <pkyzivat <at> alum.mit.edu>
2012-07-25 14:34:34 GMT
2012-07-25 14:34:34 GMT
I believe a primary motivation for PRACK was to support preconditions. (RFC 3312) The need there was to do more than one O/A exchange prior to answering an INVITE. It turns out that preconditions aren't widely used, but the mechanism also turns out to be helpful in other cases. Thanks, Paul On 7/25/12 2:25 AM, Aman wrote: > Vikram, > > PRACK is for the reliability of provisional responses, 1XX messages (except > 100). The reliability of 2xx, 3xx, 4xx, 5xx, and 6xx responses to INVITEs > is achieved using the ACK method. > > This is basically for the critical messages like 180 and 183 i.e when UAS > wants the conformation from UAC that these 1XX messages are delivered > properly. > > Check out the RFC3262 for more details on this. > > > Cheers, > Aman > > > > On Tue, Jul 24, 2012 at 12:48 PM, vikram > <vikram.hirehal <at> globaledgesoft.com>wrote: >(Continue reading)
25 Jul 2012 18:05
Re: Why do we need prack request
venu Y <toyvenu <at> gmail.com>
2012-07-25 16:05:55 GMT
2012-07-25 16:05:55 GMT
In case of VoLTE, there will be multiple O/A before media establishment. On Wed, Jul 25, 2012 at 8:04 PM, Paul Kyzivat <pkyzivat <at> alum.mit.edu> wrote: > I believe a primary motivation for PRACK was to support preconditions. > (RFC 3312) The need there was to do more than one O/A exchange prior to > answering an INVITE. It turns out that preconditions aren't widely used, > but the mechanism also turns out to be helpful in other cases. > > Thanks, > Paul > > On 7/25/12 2:25 AM, Aman wrote: > > Vikram, > > > > PRACK is for the reliability of provisional responses, 1XX messages > (except > > 100). The reliability of 2xx, 3xx, 4xx, 5xx, and 6xx responses to INVITEs > > is achieved using the ACK method. > > > > This is basically for the critical messages like 180 and 183 i.e when UAS > > wants the conformation from UAC that these 1XX messages are delivered > > properly. > > > > Check out the RFC3262 for more details on this. > > > > > > Cheers, > > Aman > >(Continue reading)
25 Jul 2012 09:50
Re: Why do we need prack request
Alex Balashov <abalashov <at> evaristesys.com>
2012-07-25 07:50:32 GMT
2012-07-25 07:50:32 GMT
A question I ask myself all the time. -- -- Alex Balashov - Principal Evariste Systems LLC 235 E Ponce de Leon Ave Suite 106 Decatur, GA 30030 Tel: +1-678-954-0670 Fax: +1-404-961-1892 Web: http://www.evaristesys.com/, http://www.alexbalashov.com/
RSS Feed