自考2008年4月计算机网络原理试题与答案（Computer network principle examination questions and answers from April 2008）.doc

自考2008年4月计算机网络原理试题与答案（Computer network principle examination questions and answers from April 2008） A single choice (the title of 24 items, each item of 1 points, a total of 24 points) In the four option of each item listed in only one is in line with the requirements of the subject, please fill in the code in question after the brackets. The wrong choice or not, choose no points. 1., the telecommunications industry generally believes that broadband backbone data transmission rate should reach (D) A.640Kbps B.640Mbps C.1Gbps D.2Gbps 2. time division allocation strategy in asynchronous time-division multiplexing TDM technology is (C) A. is pre allocated but not fixed,B. is pre allocated, fixed and unchanged C. dynamic allocation, variable D., dynamic allocation, fixed at any time 3. when the destination address field in the IEEE802.3MAC frame is all 1, it means (C) A. single address B. group address C. broadcast address D. local address 4., interception is a form of network security attack, the target of which is B A. availability, B. confidentiality C. integrity, D. security The maximum downlink data rate allowed by the 5.ADSL standard is (D) A.1Mbps B.2Mbps C.4Mbps D.8Mbps 6., in the proposed network management function of ISO, the network topology and the configuration and parameters of some network management objects are adjusted (C) A. fault management, B. security management C. performance management, D. configuration management 7. packet elimination policy for congestion prevention is used (A) A. network layer B. transport layer C. data link layer, D. presentation layer 8., the device used to implement network physical layer interconnection is (B) A. bridge B. transponder C. router, D. gateway 9. Ethernet MAC address length is (C) A.4 bit B.32 bit C.48 bit D.128 bit The port number used by 10.SMTP is (C) A.20 B.21 C.25 D.110 11. the following IP class address belongs to (A) B A.0 B. C.46 D. The 12. wireless application protocol does not include WA