综合业务数字网这是一种把电话传真数据终端等传输线路全部数字化用一个通信网进行综合操作的通信网
Integrated Services Digital Network (ISDN) This is a kind of communication network that digitizes all transmission lines such as telephone and fax data terminals with one communication network for integrated operation
以上为机器翻译结果，长、整句建议使用 人工翻译 。