Centralized automatic message accounting cama 集中式自动计费
Local automatic message accounting lama 本地自动消息记帐
Automatic message accounting 自动讯息计帐
Automatic message accounting 自动付费计算
百科解释
Automatic message accounting (AMA) provides detail billing for telephone calls. When direct distance dialing (DDD) was introduced in the US, message registers no longer sufficed for dialed telephone calls.