[SIPForum-discussion] doubt in Example-3.7 of RFC 3665

[Singh, Indresh (SNL US)]

Rob is absolutely right. Both parties maintain there own sequence number
as described in the dialog section ( 12.1 ) of RFC-3261
 
A dialog contains certain pieces of state needed for further message

transmissions within the dialog. This state consists of the dialog

ID, a local sequence number (used to order requests from the UA to

its peer), a remote sequence number (used to order requests from its

peer to the UA), a local URI, a remote URI, remote target, a boolean

flag called "secure", and a route set, which is an ordered list of

URIs. The route set is the list of servers that need to be traversed

to send a request to the peer. A dialog can also be in the "early"

state, which occurs when it is created with a provisional response,

and then transition to the "confirmed" state when a 2xx final

response arrives. For other responses, or if no response arrives at

all on that dialog, the early dialog terminates.

Regards,
 
Indresh K Singh

________________________________

From: discussion-bounces at sipforum.org
[mailto:discussion-bounces at sipforum.org] On Behalf Of Robert Sparks
Sent: Wednesday, March 21, 2007 6:06 AM
To: pankaj jain
Cc: discussion at sipforum.org
Subject: Re: [SIPForum-discussion] doubt in Example-3.7 of RFC 3665


The CSeq sequence is scoped to each endpoint (Alice keeps a
monotonically increasing sequence and Bob keeps a _separate_
monotonically increasing sequence in this dialog). 

RjS

On Mar 21, 2007, at 10:34 AM, pankaj jain wrote:


	Hi,
	I was going through RFC 3665 -- Basic Call Flow Examples: 3.7 -
Session with re-INVITE (IP Address Change)
<http://www.tech-invite.com/SIP/3665/Ti-SIP%203665-3.7%20%28v1.1%29.pdf>

	The CSeq header in 1st INVITE (Alice to Bob) is 1
	The CSeq header in 2nd INVITE (Bob to Alice) is 14
	and The CSeq header in BYE (Alice to Bob) is 2 
	
	My questions are:
	Shouldn't CSeq be monotonically increasing in a call?
	is CSeq similar to TCP seq number where both parties maintain
their own sequence numbers?
	
	-- 
	Thanks
	Pankaj Jain 
	_______________________________________________
	This is the SIP Forum discussion mailing list
	TO UNSUBSCRIBE, or edit your delivery options, please visit
http://sipforum.org/mailman/listinfo/discussion
	Post to the list at discussion at sipforum.org


-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://sipforum.org/pipermail/discussion/attachments/20070321/b72a48bf/attachment-0002.html>