DCC timers and buffer queue length
You can configure the following parameters on a dialup interface:
Link idle-timeout timer—A link idle-timeout timer starts upon setup of a link. When the timer expires, DCC disconnects the link.
Holddown timer—A holddown timer starts upon disconnection of a link. The call attempt to bring up this link can be made only after the timer expires, preventing a remote PBX from being overloaded.
Compete-idle timer—If all the channels are unavailable when DCC originates a new call, contention occurs.
An idle-timeout timer starts upon setup of a link. If a call to another destination address is placed at the same time, contention occurs. DCC starts a compete-idle timer to replace the idle-timeout timer for the link. When the idle time of the link reaches the setting of this compete-idle timer, the link disconnects.
Wait-carrier timer—Sometimes, the time DCC waits for a connection to be established varies call by call. To handle this situation, use a wait-carrier timer. A wait-carrier timer starts when a call is placed. If the connection is not established upon expiration of the timer, DCC terminates the call.
Buffer queue length—If no connection is available when a dialup interface without a buffer queue receives a packet, it will drop the packet. Configured with a buffer queue, the dialup interface will buffer the packet until a connection is available for packet sending.