a call setup and restoration schema is disclosed for providing an improved priority - based call setup and restoration schema in an optical communications system , allowing higher priority connections access to bandwidth by user - definable parameters . the call setup and restoration schema includes allowing higher priority connections to claim the resources of lower priority connections , and restoring them when bandwidth is available , or bumping another , even lower priority , connections . this aids in providing access to bandwidth by high priority services and in preventing outages or connection delays for high priority connections .