Description: Entries define permanent virtual circuits (PVCs) in the system. Each entry contains enough information to create one PVC on one network interface.

Each entry may also contain the information required to create another circuit in the system, of any kind. This other circuit we will call a companion circuit, since eventually it is going to be connected to the PVC defined in the same entry. This connection information does not need to be present, but may be, to allow for a rapid association between a PVC and its companion circuit.