Indicates the amount of time in seconds for our T3 timer.
The T3 timer is initiated by the host (i.e. the router). The T3 timer is
started whenever the S/T interface is in a deactivated state and the host
(i.e. the Router) wishes to activate the interface. As an example, for
our application, the Router would activate the interface when there was
data to be transmitted out that interface. At the point when we try
activating the interface, the T3 timer is started. During the duration
of the T3 timer, the router in trying to activate the interface will
transmit INFO 1's out the S/T interface until either a signal is detected
(from the network) or the T3 timer expires.