三洋洗衣机离合器:what is 极限的第一准则

书上有呀，单调有界函数有极限，夹逼准则。前者为第一准则

Next Generation Networking (NGN) is a broad term for a certain kind of emerging computer network architectures and technologies. It generally describes networks that natively encompass data and voice (PSTN) communications, as well as (optionally) additional media such as video.
The general idea behind NGN is that all information is transmitted via packets, like the Internet; packets are labelled according to their type (data, voice, etc) and handled differently for QoS and security purposes by traffic management equipment.

Next Generation Networks are based on Internet technologies including IP (Internet Protocol) and MPLS (Multiprotocol Label Switching). At the application level, Session Initiation Protocol (SIP) seems to be taking over from H.323.
参考资料
Wikipedia English dictionary

二楼的回答真是经典. 指数学的极限吗? 书上都有啊~