This invention describes how combined session and resource tracking in a
mobile node (MN) and/or basestation in a dynamic network resource
environment can be used to control reactions to resource shortages. The
session that is to experience a resource shortage is detected either by
the MN, or communicated to the MN where session signaling is used to
modify the session according to MN and basestation policy/configuration.
The basestation can alternatively modify the session itself with all the
session peers, on behalf of the MN. The specific new reaction to resource
shortages that is then enabled is to place the session on hold such that
the resources are freed, but so that the session state is maintained in
the peers. This is preferable to dropping the session, as is generally
the case in dynamic environments, if the likely period of resource loss
is short and the session modifications require less overhead than
restarting the session when the resources return after dropping the
session. In addition, before having resources removed, the basestation
can provide the MN with an opportunity to upgrade the priority of its
resource request compared to other users in the cell, so that a resource
auction is conducted to decide which MN actually loses its resources.