Nortel Networks 9150 - Manual (Page 45)

Remote Gateway 9150 Installation and Administration Guide 15
January 2005 Remote Gateway 9150 description
If another call is made to the host PBX before the timer expires, the timer is
reset. The timer tracks the current call.
Idle timer
The idle timer identifies the maximum length of time that an ISDN connection
remains idle before Remote Gateway 9100 Series closes it. Idle means that a
voice connection exists but is not active, and buttons are not being pressed on
digital telephones.
For example, if the idle timer is set on the RLC to 60 seconds, the ISDN call
remains open for 60 seconds after you hang up. If you or someone else dials
another number before 60 seconds have passed, another ISDN connection is not
opened.
How the timers work to control ISDN costs
The minimum call duration and idle timers work together to control ISDN
charges. The following examples describe what happens when the minimum call
duration timer is set to 59 seconds and the idle timer is set to 60 seconds.
Example 1
If the call lasts for 20 seconds and no other calls are made, the ISDN connection
drops when the minimum call duration timer reaches 59 seconds. The minimum
call duration timer expires before the idle timer.
Example 2
If the call lasts for 65 seconds and no other calls are made, the ISDN connection
drops after another 60 seconds has passed without activity. Since the ISDN call
exceeded 59 seconds, the minimum call duration timer no longer applies. The
idle timer is used, in this case, to prevent further ISDN charges.