Chapter 11. 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.

SIP takes care of the initiation, modification and termination of a session with one or more participants. The protocol makes it possible for the participants to agree on what media types they should share. You can find more information about SIP in appendix A, More About SIP, and in RFC 3261.

The SIP module in the 3Com VCX IP Telecommuting Module handles SIP requests for users who have registered on the Telecommuting Module itself or a machine connected to the Telecommuting Module (see also Local Registrar). The Telecommuting Module receives the request via the firewall (or, for the Standalone type, directly from the clients) and processes it. When the SIP negotiation is finished, the Telecommuting Module lets the media streams of this SIP session through. All media streams pass through the Telecommuting Module if the clients are located on different firewall interfaces.

These SIP functions are configured in the SIP Traffic section:

Allowed SIP methods

Filtering of SIP signaling

Local SIP domains

SIP users

SIP user authentication

RADIUS accounting for SIP

Routing of outgoing SIP requests

Routing of incoming SIP requests

SIP Methods

Enter the SIP methods you want to allow and/or authenticate. Methods that are not listed here will be blocked by the Telecommuting Module.

Common methods are predefined (from RFC 3261). Note that the standard methods ACK and CANCEL cannot be authenticated.

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