ISO IEC 15050:2003 – pdf download – Information technology — Telecommunications and information exchange between systems — Private Integrated Services Network — Inter-exchange signalling protocol — Advice Of Charge supplementary services. The three AOC supplementary services are: a) Charging information at call set-up time (AOC-S) SS-AOC-S enables the user to receive information about the charging rates at call set-up time and also to receive further information during the call if there is a change of charging rates. b) Charging information during the call (AOC-D) SS-AOC-D enables a user to receive information on the recorded charges for a call during the...