The entrance call feature can be used throughout the network. The door opener function can be used by suffix-dialling via the dial plan of the system in which the door opener circuit is configured. Suffix dialling is only possible via an S0/S2 connection (OpenScape 4000/HiPath 4000 - OpenScape 4000/HiPath 4000) or via loop signalling with DP devices.

The access code of the entrance telephone in the foreign node may be identical to the suffix dialling digits, and must be assigned the "NETW" DAR.