How to force traffic over TCP

To send SIP over TCP:

Set the property gov.nist.javax.sip.MTU_SIZE to 200. This will ensure all messages that would potentially be sent over UDP will be upgraded to TCP

The above property can be set from https://HOST:9990/console/App.html#sip-servlet (properties tab). Find the value and edit and confirm the change. You will then need to restart the service:

service fas restart

Note: You can't just disable the udp connector under https://HOST:9990/console/App.html#sip-servlet (Connectors tab), as the app server won't come up without the UDP connector.


To avoid receiving SIP over UDP:

The default port to listen for SIP over UDP is 5060. If you block UDP on port 5060 there is no real need to change the default port.

However you can alter the port by changing the sip-udp binding in the lb-socket section at:



You will also need to change the Static Server Port value of the sip-udp sip connector at

https://HOST:9990/console/App.html#sip-servlet (Connectors tab)


Again you will then need to restart the service to complete the configuration changes:

service fas restart





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