System and method for dynamically adjusting a RSVP reservation

A communication system includes a call agent that coordinates and supervises communications between endpoints. The call agent allocates a QoS agent for each endpoint involved in a call. The QoS agents generate reservations for the call in order to provide the call with a guaranteed amount of bandwidth and an established QoS. Each endpoint or location associated with an endpoint has a reservation policy that determines how calls are to be handled when a reservation is or is not obtained and when a reservation is lost or obtained during a call. The communication system is able to handle reservations, or the lack thereof, during various situations like on hold, call transfer, call forwarding, conference call, and shared line services.