Subject: [Tsvwg] [SCTP implementor]multi-home initialization

From: Bhanu Prakash <[email-masked]>
Date: Thu, 27 Jul 2006 14:47:24 +0530

Hi,

Please consider the following scenario, where endpoint A is having IP 
x.x.x.x (not multi-homed) and endpoint B is having p.p.p.p and q.q.q.q 
(multi-homed) ip addresses.

      | Endpoint 
A|                                                            |Endpoint B|
      |           --------------INIT-------------------->      |
                                          (DEST = p.p.p.p)

       |            <-----------INIT ---------------------       |
              (SRC = q.q.q.q) (has the list of ip address from B i.e 
q.q.q.q and p.p.p.p)

       |             ------------INIT ACK --------------->    |
                                  (DEST = q.q.q.q)

       |              <--------- COOKIE ECHO-----------     |     Should 
we accept this COOKIE p.p.p.p?
                                        (SRC= p.p.p.p )
  
       |               <----------COOKIE ECHO----------     | Or should 
we accept this COOKIE  q.q.q.q?
                                         (SRC = q.q.q.q)

       |              -------------COOKIE ACK---------->    |
                                          (DEST = q.q.q.q)             

If we accept COOKIE from p.p.p.p then is it considered as a new 
association or is it considerd for the INIT and INIT ACK association.? 
Please explain.

Best regards,
bhanu

---

From: "Brian F. G. Bidulock" <[email-masked]>
Date: Thu, 27 Jul 2006 09:29:13 -0600

Bhanu,

Bhanu Prakash wrote:                            (Thu, 27 Jul 2006 14:47:24)
>    A|
>    |Endpoint B|
>              |                    <--------- COOKIE ECHO-----------     |
>    Should we accept this COOKIE p.p.p.p?
>                                            (SRC= p.p.p.p )
> 
>              |                  <----------COOKIE ECHO----------     | Or
>    should we accept this COOKIE  q.q.q.q?
>                                             (SRC = q.q.q.q)

If the COOKIE-ECHO contains the valid signed Cookie from the INIT-ACK, then
it belong to nothing else (regardless of what its source address is).
Endpoint A will have verified destination q.q.q.q (with the cookie) and can
send to q.q.q.q so that is then appropriate address for the COOKIE-ACK.

The only question is why Enpoint B does not respond with an INIT-ACK?  It
should.

--brian

-- 
Brian F. G. Bidulock
[email-masked]
http://www.openss7.org/