A．当转发的帧超过最大帧长度时，只能丢弃该帧
B．当局域网负载很重，待传送的帧在网桥中堆积，超过了缓冲区空间时，只能将帧丢弃
C．如何设置帧优先级
D．如何设置数据传输速率
(58) 网络 文件访问是网络系统的基本功能，TCP/IP、XNS与SNA 均有网络文件访问协议。网络文件访问包括两种不同的形式：文件传输与文件访问。文件访问又叫做在线访问(on-lineaccess)，它 (2分)
A．要求用户直接将远地文件全部拷贝到本地文件系统
B．允许多个远地程序同时访问单个文件，在原文件上进行操作，而没有文件拷贝过程
C．要求本地用户连入局域网中
D．要求用户通过电子邮件方式交换信息
(59) ATM是一种面向连接的快速分组交换技术，它采用虚拟通道模式，通道标识基于两种标识符
A．(N)PDU、(N)IDU B)VPI、VCI
C．CONNECT .reguest、CONNECT.indication
D．(N)SAP、(N+1)SAP
(60) 在ISO“开放系统互连 管理 框架”中，将网络系统管理划分为五个功能域。这五个功能域是：配置管理、故障管理、 安全 管理、性能管理与
A．设备管理
B．用户注册管理
C．计费管理
D．域名管理
(61) What is the decimal value of the following 32-bit two’s complement number?
1111 1111 1111 1111 1111 1111 1100
A．-8
B．-4
C．4
D．8
(62) How many subsets does A have?
Let A={E，O，A，W，P，V，B}
A．12
B．36
C．64
D．128
(63) Suppose V1=，V2=，where R is the set of real numbers，+， and· are respectively addition and multiplication.Let f﹕R→R and f(x) = ex， which of the following propositions is true?
A．f is a surjective homomorphism from V1 to V2
B．f is an injective homomorphism from V1 to V2
C．f is an isomorphism from V1 to V2
D．None of the above
(64) P(n) is the predicate ’if 4 divides n then 2 divides n’. What is the truth value of P(12)?
A．10
B．F
C．T
D．None of the above
(65) An algorithm to solve a given problem has time complexity
T(n)=nlog2n-(n-1)
Given that the algorithm takes 0.8 second for a problem in which n =1024，how long should it take for a problem in which n=4096? (2 Points)
A．39 seconds
B．3.9 seconds
C．3.9 minutes
D．0.8 seconds
(66) What is the definition of a Path?
A．A sequence of vertices and the edges formed by each successive pair of vertices.
B．A walk with distinct vertices.
C．A walk with distinct edges.
D．None of the above
(67) The figure below shows a record used for recording information about a named event. Which of the following statement is incorrect? (2 Points)
VAR r﹕ record
event﹕array[1..10] of char;
place﹕array[1..20] of record
plname﹕array[1..15] of char;
date﹕ array[1..5] of record
mo﹕1..12;
day﹕1..31;
year﹕integer
end
end
end;
A．This is a one-dimensional array of records，also called a table.
B．This is so called record of arrays;
C．The event can occur in up to 20 places and on up to 5 different dates in each place.
D．A reference to r.place[i].date[j].mo will access the month of the jth occurrence，in the ith place，of the event named in r.event.
