问题
单项选择题
In (66) the strength of the carrier signal is varied to represent binary 1 or 0. (67) is a system that can map a name to an address and conversely an address to al name. (68) is a three-way handshaking authentication protocol that it’s packets are encapsulated in the point-to-point protocol. (69) is an approach that enables an ATM switch to behave like a LAN switch. (70) is an guided media which is made of glass or plastic and transmits signals in the form of light.
A．PPP
B．PAP
C．CHAP
D．LCP
答案
参考答案：C
解析：CHAP为Challenge Handshake Authentication Protocol的缩写，中文译为挑战握手认证协议。PPP是点对点协议的缩写。LCP是链路控制协议的缩写。PAP是密码认证协议的缩写。答案为C。