RFC 5626 on Managing Client-Initiated Connections in the Session Initiation Protocol (SIP)

A new Request for Comments is now available in online RFC libraries.

        RFC 5626

        Title:      Managing Client-Initiated Connections in the 
                    Session Initiation Protocol (SIP) 
        Author:     C. Jennings, Ed.,
                    R. Mahy, Ed.,
                    F. Audet, Ed.
        Status:     Standards Track
        Date:       October 2009
        Mailbox:    fluffy@cisco.com, 
                    rohan@ekabal.com, 
                    francois.audet@skypelabs.com
        Pages:      50
        Characters: 116344
        Updates:    RFC3261, RFC3327

        I-D Tag:    draft-ietf-sip-outbound-20.txt

        URL:        http://www.rfc-editor.org/rfc/rfc5626.txt

The Session Initiation Protocol (SIP) allows proxy servers to
initiate TCP connections or to send asynchronous UDP datagrams to
User Agents in order to deliver requests.  However, in a large number
of real deployments, many practical considerations, such as the
existence of firewalls and Network Address Translators (NATs) or the
use of TLS with server-provided certificates, prevent servers from
connecting to User Agents in this way.  This specification defines
behaviors for User Agents, registrars, and proxy servers that allow
requests to be delivered on existing connections established by the
User Agent.  It also defines keep-alive behaviors needed to keep NAT
bindings open and specifies the usage of multiple connections from
the User Agent to its registrar.  [STANDARDS TRACK]

This document is a product of the Session Initiation Protocol Working Group of the IETF.

This is now a Proposed Standard Protocol.

STANDARDS TRACK: This document specifies an Internet standards track
protocol for the Internet community,and requests discussion and suggestions
for improvements.  Please refer to the current edition of the Internet
Official Protocol Standards (STD 1) for the standardization state and
status of this protocol.  Distribution of this memo is unlimited.

This announcement is sent to the IETF-Announce and rfc-dist lists.
To subscribe or unsubscribe, see
  http://www.ietf.org/mailman/listinfo/ietf-announce
  http://mailman.rfc-editor.org/mailman/listinfo/rfc-dist

For searching the RFC series, see http://www.rfc-editor.org/rfcsearch.html.
For downloading RFCs, see http://www.rfc-editor.org/rfc.html.

Requests for special distribution should be addressed to either the
author of the RFC in question, or to rfc-editor@rfc-editor.org.  Unless
specifically noted otherwise on the RFC itself, all RFCs are for
unlimited distribution.

The RFC Editor Team
USC/Information Sciences Institute