When a GDM receives a request to create PDP, it processes
and forwards the request to the GGSN and saves the information
related to the request. This object defines the time during
which the information is maintained by the GDM. Any subsequent
retries by the SGSN within this time period will be forwarded
to the same GGSN, but the timer will not be reset if a retry
occurs before it has expired.