Aastra Telecom 55I, 57I CT, 53I manual Symmetric UDP Signaling

Configuring Advanced Operational Features

Advanced Operational Features

Symmetric UDP Signaling

By default, the IP phones use symmetric UDP signaling for outgoing UDP SIP messages. When symmetric UDP is enabled, the IP phone generates and listens for UDP messages using port 5060.

You can manually disable symmetric UDP signaling using the IP phone’s configuration file. When you disable symmetric UDP signaling, then the IP phone chooses a random source port for UDP messages.

The IP phone also chooses a random source port for UDP messages if you configure a backup proxy server, registrar server, or outbound proxy server.

An Administrator can configure symmetric UDP signaling using the configuration files only.

Configuring Symmetric UDP Signaling Using the Configuration Files

You use the following parameter to enable or disable Symmetric UDP Signaling in the configuration files:

•sip symmetric udp signaling

Configuration Files

For the specific parameter you can set in the configuration files, see Appendix A, the section, “RTP, Codec, DTMF Global Settings” on page A-77.

Advanced Operational Features

41-001160-00, Release 2.1, Rev 04 6-27