【单选题】The File Transfer Protocol (FTP) is a standard network protocol used for the transfer of computer （ ） between a client and server on a computer network.FTP is built on a （ ） model architecture using separate control and data connections between the client and the server. FTP users may authenticate themselves with a （请作答此空） sign-in protocol, normally in the form of a username and password, but can connect anonymously if the server is configured to allow it. For secure transmission that protects the username and password, and encrypts the content, FTP is often secured with SSL/TLS (FTPS) or replaced with SSH File Transfer Protocol (SFTP).The first FTP client applications were （ ） programs developed before operating systems had graphical user interfaces, and are still shipped with most Windows, Unix, and Linux operating systems. Many FTP clients and automation utilities have since been developed for desktops, servers, mobile devices, and hardware, and FTP has been incorporated into productivity applications, such as HTML editors.FTP may run in （ ） mode, which determines how the data connection is established. In both cases, the client creates a TCP control connection from a random, usually an unprivileged, port N to the FTP server command port 21.In active mode, the client starts listening for incoming data connections from the server on port M. It sends the FTP command PORT M to inform the server on which port it is listening. The server then initiates a data channel to the client from its port 20, the FTP server data port.In situations where the client is behind a firewall and unable to accept incoming TCP connections, passive mode may be used. In this mode, the client uses the control connection to send a PASV command to the server and then receives a server IP address and server port number from the server, which the client then uses to open a data connection from an arbitrary client port to the server IP address and server port number received.Both modes were updated in September 1998 to support IPv6. Further changes were introduced to the passive mode at that time, updating it to extended passive mode.
A、encrypt
B、decryption
C、clear-text
D、secure
答案：C
解析：The File Transfer Protocol (FTP) is a standard network protocol used for the transfer of computer files between a client and server on a computer network.FTP is built on a client-server model architecture using separate control and data connections between the client and the server. FTP users may authenticate themselves with a clear-text sign-in protocol, normally in the form of a username and password, but can connect anonymously if the server is configured to allow it. For secure transmission that protects the username and password, and encrypts the content, FTP is often secured with SSL/TLS (FTPS) or replaced with SSH File Transfer Protocol (SFTP).The first FTP client applications were command-line programs developed before operating systems had graphical user interfaces, and are still shipped with most Windows, Unix, and Linux operating systems. Many FTP clients and automation utilities have since been developed for desktops, servers, mobile devices, and hardware, and FTP has been incorporated into productivity applications, such as HTML editors.FTP may run in active or passive mode, which determines how the data connection is established. In both cases, the client creates a TCP control connection from a random, usually an unprivileged, port N to the FTP server command port 21.In active mode, the client starts listening for incoming data connections from the server on port M. It sends the FTP command PORT M to inform the server on which port it is listening. The server then initiates a data channel to the client from its port 20, the FTP server data port.In situations where the client is behind a firewall and unable to accept incoming TCP connections, passive mode may be used. In this mode, the client uses the control connection to send a PASV command to the server and then receives a server IP address and server port number from the server, which the client then uses to open a data connection from an arbitrary client port to the server IP address and server port number received.Both modes were updated in September 1998 to support IPv6. Further changes were introduced to the passive mode at that time, updating it to extended passive mode.
【单选题】SNMP 管理模型由4 部分组成，它们是管理站、（ ）、网络管理协议和管理信息库。
A、管理控制台
B、管理代理
C、管理标准
D、网络管理员
答案：B
解析：网络管理系统由以下4个要素组成：（1）管理站（Network Manager）。管理站是位于网络系统主干或者靠近主干的工作站，是网络管理系统的核心，负责管理代理和管理信息库，定期查询代理信息，确定独立的网络设备和网络状态是否正常。（2）代理（Agent）。代理又称为管理代理，位于被管理设备内部。负责收集被管理设备的各种信息和响应管理站的命令或请求，并将其传输到MIB数据库中。代理所在地设备可以是网管交换机、服务器、网桥、路由器、网关及任何合法节点的计算机。（3）管理信息库（Management Information Base，MIB）。相当于一个虚拟数据库，提供有关被管理网络各类系统和设备的信息，属于分布式数据库。（4）网络管理协议。用于管理站和代理之间传递、交互信息。常见的网管协议有SNMP和CMIS/CMIP。网管站通过SNMP向被管设备的网络管理代理发出各种请求报文，代理则接收这些请求后完成相应的操作，可以把自身信息主动通知给网管站
【单选题】张某购买了一张有注册商标的应用软件光盘，擅自复制出售，则其行为侵犯了（ ）。
A、注册商标专用权
B、光盘所有权
C、软件著作权
D、软件著作权与商标权
答案：C
解析：这里用户仅仅是复制出售，侵犯了著作权，不涉及假冒商标等问题，因此不考虑商标权问题。
【单选题】默认情况下，FTP 服务器的控制端口为（ ），上传文件时的端口为（请作答此空）。
A、大于1024 的端口
B、20
C、80
D、21
答案：B
解析：ftp服务器在默认情况下工作时，会建立两个连接，一个是控制连接使用21号端口，另一个连接是数据连接，使用20号端口。
【单选题】在Windows的cmd命令行窗口中，输入（）命令将会得到如下图所示的结果。
A、net view
B、nbtstat-r
C、netstat
D、nslookup
答案：C
【单选题】下面的网络地址中，不能作为目标地址的是（ ）。
A、0.0.0.0
B、127.0.0.1
C、10.255.255.255
D、192.168.0.1
答案：A
解析：本地回环测试地址（127.0.0.1）既能作源地址又能作目的地址。广播地址只能作目的地址，不能作源地址。一个标准的主机有效IP地址既能作源地址又能作目的地址。0.0.0.0代表本地，只能作源地址。
【单选题】IEEE 802.11 的 MAC 层协议是（ ）。
A、CSMA/CD
B、CSMA/CA
C、Token Ring
D、TDM
答案：B
解析：IEEE 802.11采用了类似于IEEE 802.3 CSMA/CD协议的载波侦听多路访问/冲突避免协议（Carrier Sense Multiple Access/Collision Avoidance，CSMA/CA），不采用CSMA/CD协议的原因有两点：①无线网络中，接收信号的强度往往远小于发送信号，因此要实现碰撞的花费过大；②隐蔽站（隐蔽终端问题）
【单选题】在 HTML 中，＜ol>标签的作用是( )。
A、定义列表条目
B、定义无序列表
C、定义有序列表
D、定义文本不换行
答案：C
解析：＜ol> 标签定义有序列表。
【单选题】（请作答此空）是计算机内部运算部件一次能同时处理的二进制数据位数。计算机的运行速度使用每秒钟所能执行的（ ）指令数目来评估。
A、字长
B、带宽
C、内存
D、寄存器
答案：A
解析：在同一时间中处理二进制数的位数叫字长。通常称处理字长为8位数据的CPU叫8位CPU，32位CPU就是在同一时间内处理字长为32位的二进制数据。计算机的运行速度使用每秒钟所能执行的加法指令数目来评估。
【单选题】如果在网络入口封锁了TCP和UDP端口21、23和25，下面哪种应用可以访问该网络（23）。
A、FTP
B、DNS
C、SMTP
D、Telnet
答案：B
解析：封锁了TCP和UDP端口21、23和25，由于TCP 21端口对应了应用层FTP服务，TCP 23端口对应了应用层Telnet服务，TCP 25端口对应了应用层SMTP服务，意味着封禁了FTP、SMTP、Telnet服务，唯有DNS服务没有被封禁（DNS服务对应了TCP 和UDP的53号端口）。
