supplementary service

常见例句

Supplementary service: law firm, language training school, preparatory college, overseas school, employment agency.
配套服务：律师事务所、语言培训学校、预科学校、海外学院、就业机构等。
The Sub-addressing (SUB) supplementary service allows the called (served) user to expand his addressing capacity beyond the one given by the ISDN number.
子寻址（SUB）补充业务允许被叫（被服务）用户在给定的ISDN号码基础上扩展其寻址容量。
www.ptsn.net.cn
Because there's an essential signaling difference between IP phone and traditional voice service, IP phone supplementary service is developed based on special protocols.
由于IP电话系统在信令结构方面与传统电话系统的集中模型有本质的区别，因此基于IP电话系统附加业务的开发和控制协议具有不同的特点。

The Unstructured Supplementary Service Data (USSD) code (which we won't reproduce here) apparently only works on Samsung phones running Touchwiz, and only if you are directed to the dodgy destination while inside the stock browser (rather than Chrome, for example).
ENGADGET: 'Dirty USSD' code could automatically wipe your Samsung TouchWiz device (updated)