The Called Party Subaddress (CdS) is an information element in digital
networks. It contains the subaddress of the called subscriber. A subaddress is transmitted in the network up to the exchange of the called subscriber. If the end subscriber is authorised to use the subaddress service feature, then the information is transferred with the setup message. Otherwise, the message
in the local exchange
. In contrast to the Called Party Subaddress, the Calling Party Subaddress (CgS) is the subaddress of the calling subscriber.