> -----Original Message-----
> From: James Undery [mailto:[EMAIL PROTECTED]]
> Sent: Tuesday, February 27, 2001 4:34 AM
> To: Jonathan Rosenberg
> Cc: Scott Happell; 'Venkatesh Venkataramanan';
> [EMAIL PROTECTED]
> Subject: Re: [Sip-implementors] RE: [SIP] Question regarding CSEQ
> processing with PRACK...
> 
> 
> 
> 
> Jonathan Rosenberg wrote:
> 
> > Scott is correct. The next CSeq is 4.
> 
> Or (obviously) any other number greater than four, the requirement is
> strictly increasing monotonic function. This is an important 
> feature most
> people seem to miss.

Actually, according to both rfc2543 and bis, it does increase by one:

>From rfc2543:
Consecutive requests that differ in request method, headers or body,
   but have the same Call-ID MUST contain strictly monotonically
   increasing and contiguous sequence numbers; sequence numbers do not
   wrap around. 

Contiguous does imply "increment by one".

I'll admit that my recollection on this was also different; somehow I had
thought that it could increase by any amount. Incrementing by one is
probably a good thing, since ordering is near impossible without that. The
only drawback is survival across reboots. In that case, a UA may want to be
prepared to reset the current cseq on a call leg if it gets one that is
drastically higher than the previous one. 

Anyway, I hope my clouded recollection is not shared by too many others...
is there anyone that has implemented an increment that is not 1?

-Jonathan R.

---
Jonathan D. Rosenberg                       72 Eagle Rock Ave.
Chief Scientist                             First Floor
dynamicsoft                                 East Hanover, NJ 07936
[EMAIL PROTECTED]                     FAX:   (973) 952-5050
http://www.cs.columbia.edu/~jdrosen         PHONE: (973) 952-5000
http://www.dynamicsoft.com
> 
> James Undery
> 
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