Subject: I-D ACTION:draft-jennings-sip-hashcash-05.txt

From: [email-masked]
Date: Mon, 04 Jun 2007 18:50:01 -0400

A New Internet-Draft is available from the on-line Internet-Drafts 
directories.

	Title		: Computational Puzzles for SPAM Reduction in SIP
	Author(s)	: C. Jennings
	Filename	: draft-jennings-sip-hashcash-05.txt
	Pages		: 29
	Date		: 2007-6-4
	
One of the techniques used in SPAM prevention and various solutions
   for denial of service attacks is to force the SIP client requesting a
   service to perform a calculation that limits the rate and increases
   the cost of the request.  This draft defines a way to allow a UAS to
   ask the UAC to compute a computationally expensive hash based
   function and present the result to the UAS.  Although the computation
   is expensive for the UAC to compute, it is cheap for the UAS to
   verify.  The solution also allows for proxies to compute and check
   the puzzle on behalf of the UAC or UAS.

   This draft currently outlines enough information to evaluate and
   consider this approach or even run experiments.  It would need
   finalization around the forking topics discussed in the open issues
   before it would be implementable in production system.

A URL for this Internet-Draft is:
http://www.ietf.org/internet-drafts/draft-jennings-sip-hashcash-05.txt

To remove yourself from the I-D Announcement list, send a message to 
[email-masked] with the word unsubscribe in the body of 
the message. 
You can also visit https://www1.ietf.org/mailman/listinfo/I-D-announce 
to change your subscription settings.

Internet-Drafts are also available by anonymous FTP. Login with the 
username "anonymous" and a password of your e-mail address. After 
logging in, type "cd internet-drafts" and then 
"get draft-jennings-sip-hashcash-05.txt".

A list of Internet-Drafts directories can be found in
http://www.ietf.org/shadow.html 
or ftp://ftp.ietf.org/ietf/1shadow-sites.txt

Internet-Drafts can also be obtained by e-mail.

Send a message to:
	[email-masked].
In the body type:
	"FILE /internet-drafts/draft-jennings-sip-hashcash-05.txt".
	
NOTE:	The mail server at ietf.org can return the document in
	MIME-encoded form by using the "mpack" utility.  To use this
	feature, insert the command "ENCODING mime" before the "FILE"
	command.  To decode the response(s), you will need "munpack" or
	a MIME-compliant mail reader.  Different MIME-compliant mail readers
	exhibit different behavior, especially when dealing with
	"multipart" MIME messages (i.e. documents which have been split
	up into multiple messages), so check your local documentation on
	how to manipulate these messages.

Below is the data which will enable a MIME compliant mail reader
implementation to automatically retrieve the ASCII version of the
Internet-Draft.
_______________________________________________
I-D-Announce mailing list
[email-masked]
https://www1.ietf.org/mailman/listinfo/i-d-announce