Subject: [dns-dir] DNS-EW: draft-malas-dispatch-sip-egress-route-00.txt

From: DNS_EARLY_WARNING <[email-masked]>
Date: Tue, 2 Mar 2010 14:40:01 -0500

Count:       38 

Dispatch                                                        D. Malas
Internet-Draft                                                 CableLabs
Intended status: Informational                             March 1, 2010
Expires: September 2, 2010

                      SIP Egress Route Use in ENUM
                draft-malas-dispatch-sip-egress-route-00

 Abstract

   In some cases a UA (or proxy) within a Session Initiation Protocol
   [RFC3261] Service Provider (SSP) has multiple parallel egress proxy
   options to reach an ingress proxy within another SSP to reach the
   target UA.  If the originating SSP uses ENUM to identify the ingress
   proxy of the target SSP, there is currently no way for the ENUM NAPTR
   response to identify a specific preferred egress proxy from the set
   of multiple parallel proxies.  This draft solves this problem by
   defining a method for returning deterministic routing information
   within an ENUM NAPTR response enabling the UA (or proxy) to choose a
   preferred egress proxy.  Using this information, the originating UA
   now sends the SIP request through the predetermined preferred egress
   proxy to reach the target SSP's proxy.  This document describes
   several methods to make this determination by incorporating variables
   into a SIP service URI contained in the E.164 Number Mapping (ENUM)
   response.