第58题： 三层网络设计方案中，（  ）是核心层的功能。
A.不同区域的高速数据转发
B.用户认证、计费管理
C.终端用户接入网络
D.实现网络的访问策略控制
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第59题： 五阶段迭代周期模型把网络开发过程分为需求分析、通信规范分析、逻辑网络设计、物理网络设计、安装和维护等五个阶段。以下叙述中正确的是（  ）。
A.需求分析阶段应尽量明确定义用户需求，输出需求规范、通信规范
B.逻辑网络设计阶段设计人员一般更加关注于网络层的连接图
C.物理网络设计阶段要输出网络物理结构图、布线方案、IP地址方案等
D.安装和维护阶段要确定设备和部件清单、安装测试计划，进行安装调试
答案解析与讨论：www.cnitpm.com/st/4189529078.html

第60题： 以下关于网络冗余设计的叙述中，错误的是（  ）。
A.网络冗余设计避免网络组件单点失效造成应用失效
B.通常情况下主路径与备用路径承担相同的网络负载
C.负载分担是通过并行链路提供流量分担来提高性能
D.网络中存在备用链路时，可以考虑加入负载分担设计
答案解析与讨论：www.cnitpm.com/st/4189616038.html

第62题： A virtual (  ) network, or VPN, is an encrypted connection over the Internet from a device to a network. The encrypted connection helps ensure that sensitive data is safely (  ). It prevents (  ) people from eavesdropping on the traffic and allows the user to conduct work remotely. Traffic on the virtual network is sent securely by establishing an encrypted connection across the Internet known as a (  ).A remote access VPN securely connects a device outside the corporate office. A site-to-site VPN connects the corporate office to branch offices over the Internet. Site-to-site VPNs are used when distance makes it impractical to have direct network connections between these offices. Think of site-to-site access as (  ) to network.
（1）A. public
B. private
C. personal
D. proper
（2）A. encoded
B. encrypted
C. stored
D. transmitted
（3）A. employed
B. authorized
C. unauthorized
D. criminal
（4）A. channel
B. path
C. tunnel
D. route
（5）A. network
B. device
C. computer
D. endpoin
答案解析与讨论：www.cnitpm.com/st/4189813956.html