爲了幫助大家更好備考2016年上半年的計算機四級考試，小編爲大家準備了以下四級考試選擇題，希望對大家有所幫助!
1)以下關於網絡協議三個要素之一的語法的描述，哪一個是正確的?
A)語法解釋比特流的.每一部分的意義
B)語法規定用戶數據與控制信息的結構與格式
C)語法對事件實現的順序作了詳細地說明
D)語法對協議實現方法作出明確的規定
2)如果物理層採用了曼徹斯特編碼，那麼信號傳輸速率爲10Mbps時，發送時鐘信號頻率應該爲
A)5MHz B)10MHz
C)15MHz D)20MHz
3)符合IEEE802.3標準的Ethernet網物理地址採用連續編碼方法，它使用的地址長度爲
A)8bit B)16bit
C)48bit D)64bit
4)網絡環境中實現分佈式進程通信必須解決哪3個主要的問題?
Ⅰ. 進程命名與尋址方法 Ⅱ. 多重協議的識別
Ⅲ. 協議轉換 Ⅳ. 進程間相互作用的模式
A)Ⅰ、Ⅱ和Ⅲ B)Ⅰ、Ⅱ和Ⅳ
C)Ⅱ、Ⅲ和Ⅳ D)Ⅰ、Ⅲ和Ⅳ (55)10Gbps Ethernet與10Mbps、100Mbps和1Gbps Ethernet採用了完全相同的
Ⅰ. 幀格式 Ⅱ. 邏輯鏈路控制子層協議
Ⅲ. 物理層標準 Ⅳ. 數據編碼方法
A)Ⅰ和Ⅱ B)Ⅰ、Ⅱ和Ⅲ
C)Ⅱ和Ⅳ D)Ⅱ、Ⅲ和Ⅳ
6)What is the decimal value of the binary value 10010?
A)16 B)17 C)18 D)19
7)In a computer, which of the following is the longest period?
A)Beat period B)Machine period C)Instruction period D)CPU period
8)Which of the following is not an AVL tree?
9)Traversing a binary tree in preorder is equivalent to
A)Traversing the forest corresponding to the binary tree in root-first order.
B)Traversing the forest corresponding to the binary tree in root-last order.
C)Traversing the forest corresponding to the binary tree in breadth-first order.
D)None of the above.
10)Which of the following methods is used to increase the number of processes sharing the CPU?
A)Interrupt B)Scheduler
C)Swapping D)Working Set
11)Which of the following statements describe(s) the properties of a purely segmented memory system?
Ⅰ divides memory into units of equal size
Ⅱ permits implementation of virtual memory
Ⅲ suffers from internal fragmentation
A)Ⅰ only B)Ⅱ only
C)Ⅲ only D)Ⅰand Ⅲ
12)As an important phase in software development, software design is the continuation of software requirement analysis phase.
Ⅰware structure Ⅱware procedure
Ⅲware module Ⅳware document
which of the following should be included in software design phase?
A)Ⅰand Ⅱ B)Ⅱand Ⅲ
C)Ⅰ,Ⅱ and Ⅲ D)All
13)White box testing of software testing is a test for software structure. Which of the following item should not be included in the content of white box?
A)boundary value analysis B)statement testing
C)branch testing D)path testing
14)Consider a relation R ( A，B，C，D ) with the following dependencies：
AB ? C, CD ? E, DE ? B.
A candidate key of this relation is
A)AB B)ABC C)ABD D)ABE
15)Let R and S be the following relations：
A)3 B)4 C)5 D)6
16)The Pentium includes hardware for both segmentation and paging. Both mechanisms can be disabled, allowing the user to choose from four distinct views of memory. Now the most frequently used view(such as Unix System V) is
A)Unsegmented unpaged memory B)Unsegmented paged memory
C)Segmented unpaged memory D)Segmented paged memory
17)ASCII is a 7-bit code used to represent numeric, alphabetic, and special printable characters. It also includes codes for control characters, which are
A)printable or displayable B)not printable or displayable
C)not printable but displayable D)printable but not displayable
18)In most wide area networks, the communication
;subnet consists of two distinct components：transmission lines and
A)networts B)switching elements
C)computers D)data terminal equipment
19)To accommodate the longest path allowed by 802.3,the slot time has been set to 512 bit times,or
A)0.512μs B)5.12μs
C)51.2μs D)512μs
20)TCP(Transmission Control Protocol) was specifically designed to provide a reliable end-to-end byte stream over a(n)
A)IP address B)reliable network
C)socket D)unreliable internetwork
