Subject: [sip-overload] draft-jones-sip-overload-sce-00.txt

From: "Paul E. Jones" <[email-masked]>
Date: Thu, 1 Jul 2010 01:05:35 -0400

Folks,

I would like to bring to your attention an initial draft related to overload
control of SIP servers, with a particular emphasis on servers that are not
SIP proxies (i.e., B2BUAs and GWs).

During the call on Tuesday, I think we gained a better understanding of the
scope of the work done on overload control to this point.  We definitely
agree that a rate-based mechanism is very appropriate for SIP proxy servers.
However, in any SIP network, there are many SBCs, GWs, and other such
devices that are constrained by various resources that can be summarily
represented with a single capacity value that we refer to as the Session
Capacity Estimate.

The idea is that a device (e.g., SBC, PBX, etc.) that wishes to select from
amongst any number of peer devices (other SBCs, GWs, etc.) would use the SCE
value in order to help in this selection process.  To avoid directing too
much traffic too quickly, we assume the rate control mechanisms currently
under discussion in this WG might also be employed.  Alternatively, the
device might use a simple round-robin approach to selecting a peer device.
The latter has proven to be quite effective in the past, but standardized
SIP signaling has not been defined thus far.

This is an initial draft and it certainly has room for growth.  However, we
felt it was important to at least get this on the table for consideration in
addition to the rate-based control mechanisms that have been identified for
SIP proxy servers.

Your comments and feedback are most welcome.

Paul

> -----Original Message-----
> From: [email-masked] [mailto:[email-masked]]
> On Behalf Of [email-masked]
> Sent: Thursday, July 01, 2010 12:45 AM
> To: [email-masked]
> Subject: I-D Action:draft-jones-sip-overload-sce-00.txt
> 
> A New Internet-Draft is available from the on-line Internet-Drafts
> directories.
> 
> 	Title           : Transmission of a Session Capacity Estimate (SCE)
> to Prevent Session Initiation Protocol (SIP) Server Overload
> 	Author(s)       : P. Jones, et al.
> 	Filename        : draft-jones-sip-overload-sce-00.txt
> 	Pages           : 6
> 	Date            : 2010-06-30
> 
> This memo describes a method of preventing overload of Session Initiation
> Protocol (SIP) servers through the calculation, conveyance, and usage of a
> value referred to as the Session Capacity Estimate (SCE), a value that
> summarily represents the capacity of a SIP server.
> 
> A URL for this Internet-Draft is:
> http://www.ietf.org/internet-drafts/draft-jones-sip-overload-sce-00.txt
> 
> Internet-Drafts are also available by anonymous FTP at:
> ftp://ftp.ietf.org/internet-drafts/
> 
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