Abstract: A telecommunication system providing centrex services, and having an attendant position serving users from diverse customer locations. Users at a satellite customer location connected to one exchange and employing ISDN terminals are provided with access to an attendant position at a main customer location connected to another exchange. ISDN messages from users at the satellite location requesting attendant services are recognized at the exchange associated with the satellite location and transmitted as analog flash signals via an analog signaling trunk to the exchange to which the attendant is connected. The exchange receiving the flash signals interpret the signals as requests for attendant services and provides the necessary connections to the attendant's position.