supplementary service

Features are functionalities of terminal equipment and telecommunications networks. They can be service-independent and offer additional functions that facilitate and simplify the operation of the terminal device. Features can be based on the service features.

In the case of telephones, such features include loudspeaking, redialing, speakerphone, disconnect, transfer, automatic callback, call pickup, or call forwarding.

Digital network features included in rates and charges include called party number portability( COLP), called party number suppression ( COLR), call charge information ( AoC), closed user group dialing ( CUG), call waiting ( CW), automatic redialing ( CCBS), conference calling ( CONF), conference reservation ( MMC), call forward ing( CFU), call forwarding on busy( CFB), call forwarding on no answer( CFNR), call forwarding( CD), call charge pickup( FPH), malicious caller identification ( MCID), subaddressing( SUB), three-partyconference ( 3PTY), end-to-end signaling, user-to-user signaling service ( UUS), and call hold( CH).