题库精选:CCNA考试自测题第1卷

　　18) What is IP (什么是I P )？

　　A. It is the transport mechanism for upper layer services

　　B. It is the session layer API for making the transport layer independent

　　C. It is the network layer protocol that moves data from one node to another

　　D. It is the physical layer protocol for Internet connections

　　19) What is ICMP (什么是I C M P )？

　　A. It is a network layer protocol that handles control messages

　　B. It is a network layer protocol that resolves addresses

　　C. It is a session layer API that makes remote procedures transparent to a user

　　D. It is a transport layer function for unreliable transport

　　20) Ping sends an ICMP echo command to an IP address in order to determine whether anetwork connection exists to that node (Ping向一个I P地址发送了一个I C M P回送命令，目的是确定是否存在到那个节点的网络连接)？

　　A. True

　　B. False

　　21) Which of the following best describes TCP/IP (下面的哪句话最准确地说明了T C P / I P )？

　　A. A static protocol

　　B. A proprietary protocol

　　C. A collection of internetworking protocols

　　22) UDP and TCP represent mechanisms used by which layer of the TCP/IP (UDP和T C P表示了T C P / I P的哪层使用的机制)？

　　A. Data link layer

　　B. Physical layer

　　C. Presentation layer

　　D. Transport layer

　　23) RPCs provide which of the following (RPC提供了下面的哪个功能)？

　　A. Connection-oriented session

　　B. Transparency to make remote calls look local

　　C. Portability of applications between heterogeneous systems

　　D. A and C only

　　E. B and C only

　　F. A, B, and C

　　24) Distributed Computing Environment (DCE) is an example of (分布式计算环境( D E C )是下面的哪一项的一个例子)？

　　A. OSI model

　　B. RPC implementation

　　C. Extreme Data Representation

　　D. A and B

　　25) Which statement is true of WinSock (下面对Wi n S o c k的哪一句陈述是正确的)？

　　A. It is a MAC application

　　B. It represents a graphical user interface

　　C. It represents a network layer

　　D. It provides the means for sharing an Internet connection between multiple IP protocol　suite utilities