Sets the duration, in milliseconds, of the T303 signaling timer on this port, defaulting to 4000 ms; this is the ITU-T Q.2931 timer governing how long the calling side waits for a response to an initial SETUP message before retrying or abandoning the call, per ITU-T Q.2931. Admins normally leave signaling timers at their standard defaults, adjusting them only to interoperate with a far-end switch that uses nonstandard timer values or to work around a specific signaling interoperability issue.