Chapter 9. SIP Traffic
SIP(Session Initiation Protocol) is a protocol for creating and terminating various media stream sessions over an IP
network.It is for example used for Internet telephone calls and distribution of video streams.
SIPtakes care of the initiation, modification and termination of a session with one or more participants. The
protocolmakes it possible for the participants to agree on what media types they should share. You can find more
informationabout SIP in appendix A, More About SIP, and in RFC 3261.
Youfind examples on how to configure your 3Com VCX IP Telecommuting Module for SIP in chapter 4, How To
ConfigureSIP.
TheSIP module in 3Com VCX IP Telecommuting Module handles SIP requests for users who have registered on a
machineconnected to the Telecommuting Module. The module forwards the request through the Telecommuting
Module,which enables users behind different network interfaces to make contact. The SIP module controls the
securityrules to temporarily let through the media streams that the users agree on, on their assigned ports.
Youmust enter a DNS server and a Default gateway on the Basic Configuration page to make the SIP module
worksatisfactorily.
TheseSIP functions are configured in the SIP Traffic section:
•AllowedSIP methods
•Routingof incoming SIP requests

SIP Methods

Enterthe SIP methods you want to allow and/or authenticate. Methods that are not listed here will be blocked by the
TelecommutingModule.
Commonmethods are predefined (from RFC 3261). Note that the standard methods ACK and CANCEL can’t be
authenticated.
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