Setting up a SIP (Session Initiation Protocol) connection in a dual stack network using connection oriented transports

Document Type Expired Internet-Draft (individual)
Last updated 2017-04-24 (latest revision 2016-10-21)
Stream (None)
Intended RFC status (None)
Expired & archived
plain text pdf html bibtex
Stream Stream state (No stream defined)
Consensus Boilerplate Unknown
RFC Editor Note (None)
IESG IESG state Expired
Telechat date
Responsible AD (None)
Send notices to (None)

This Internet-Draft is no longer active. A copy of the expired Internet-Draft can be found at


The Session Initiation Protocol (SIP) supports multiple transports running both over IPv4 and IPv6 protocols. In more and more cases, a SIP user agent (UA) is connected to multiple network interfaces. In these cases setting up a connection from a dual stack client to a dual stack server may suffer from the issues described in RFC 6555 [RFC6555] - Happy Eyeballs - significant delays in the process of setting up a working flow to a server. This negatively affects user experience. This document builds on RFC 6555 and explains how a RFC3261 [RFC3261] compliant SIP implementation can quickly set up working flows to a given hostname (located by using DNS NAPTR and SRV lookups) in a dual stack network using connection oriented transport protocols. A solution for connectionless transport protocols is discussed in a separate document.


Olle Johansson (
Gonzalo Salgueiro (
Dale Worley (

(Note: The e-mail addresses provided for the authors of this Internet-Draft may no longer be valid.)