Subject: [Sip] question about 180 Ringing

From: 陈善学 <[email-masked]>
Date: Mon, 3 Dec 2001 13:32:31 +0800

Dear all
I have a question as follow.The figure exists in bis-05.
I have change "180 Rining"
My figure:
                 atlanta.com  . . . biloxi.com
             .      proxy              proxy     .
           .                                       .
   Alice's  . . . . . . . . . . . . . . . . . . . .  Bob's
  softphone                                        SIP Phone
     |                |                |                |
     |    INVITE F1   |                |                |
     |--------------->|    INVITE F3   |                |
     |  100 Trying F2 |--------------->|    INVITE F5   |
     |<---------------|  100 Trying F4 |--------------->|
     |                |<-------------- |                |
     |                  180 Ringing F7                  |
     |<-------------------------------------------------|
     |                                       200 OK F9  |
     |                |    200 OK F10  |<---------------|
     |    200 OK F11  |<---------------|                |
     |<---------------|                |                |
     |                       ACK F12                    |
     |------------------------------------------------->|
     |                   Media Session                  |
     |<================================================>|
     |                       BYE F13                    |
     |<-------------------------------------------------|
     |                     200 OK F14                   |
     |------------------------------------------------->|
     |                                                  |
I considered that the middle state is not important,and the
endpoint "the bob's sipphone" has known the "contact" about
Alice's direct adress.So bob can send "180 Ringing" directly
to alice rather than passed hop by hop.

The original figure:
                 atlanta.com  . . . biloxi.com
             .      proxy              proxy     .
           .                                       .
   Alice's  . . . . . . . . . . . . . . . . . . . .  Bob's
  softphone                                        SIP Phone
     |                |                |                |
     |    INVITE F1   |                |                |
     |--------------->|    INVITE F3   |                |
     |  100 Trying F2 |--------------->|    INVITE F5   |
     |<---------------|  100 Trying F4 |--------------->|
     |                |<-------------- | 180 Ringing F6 |
     |                | 180 Ringing F7 |<---------------|
     | 180 Ringing F8 |<---------------|     200 OK F9  |
     |<---------------|    200 OK F10  |<---------------|
     |    200 OK F11  |<---------------|                |
     |<---------------|                |                |
     |                       ACK F12                    |
     |------------------------------------------------->|
     |                   Media Session                  |
     |<================================================>|
     |                       BYE F13                    |
     |<-------------------------------------------------|
     |                     200 OK F14                   |
     |------------------------------------------------->|
     |                                                  |

---

From: [email-masked]
Date: Mon, 3 Dec 2001 11:06:00 +0530

Hi,

But I guess the figure in bis05 assumes that we have a Via header in the
requests that makes it necessary for responses to be sent hop by hop.

-Regards
R.Kamath

陈

善学 <[email-masked]> on 12/03/2001 05:32:31 AM

To:   [email-masked]
cc:    (bcc: P Raghavendra Kamath/HSSBLR)

Subject:  [Sip] question about 180 Ringing

Dear all

The original figure: