In telephone, an intelligent private switchboard which may provide extra facilities, e. g. facsimile, database interrogation, in addition to routing incoming and outgoing telephone calls.

• 电话技术中的一种智能专用交换机,可以提供额外的功能,例如除了对打进打出的电话作路由选择外,还可以提供传真、数据库询问等。