第58題： 三層網(wǎng)絡設計方案中，（  ）是核心層的功能。
A.不同區(qū)域的高速數(shù)據(jù)轉(zhuǎn)發(fā)
B.用戶認證、計費管理
C.終端用戶接入網(wǎng)絡
D.實現(xiàn)網(wǎng)絡的訪問策略控制
答案解析與討論：www.ichunya.com/st/4189420483.html

第59題： 五階段迭代周期模型把網(wǎng)絡開發(fā)過程分為需求分析、通信規(guī)范分析、邏輯網(wǎng)絡設計、物理網(wǎng)絡設計、安裝和維護等五個階段。以下敘述中正確的是（  ）。
A.需求分析階段應盡量明確定義用戶需求，輸出需求規(guī)范、通信規(guī)范
B.邏輯網(wǎng)絡設計階段設計人員一般更加關注于網(wǎng)絡層的連接圖
C.物理網(wǎng)絡設計階段要輸出網(wǎng)絡物理結(jié)構(gòu)圖、布線方案、IP地址方案等
D.安裝和維護階段要確定設備和部件清單、安裝測試計劃，進行安裝調(diào)試
答案解析與討論：www.ichunya.com/st/4189529078.html

第60題： 以下關于網(wǎng)絡冗余設計的敘述中，錯誤的是（  ）。
A.網(wǎng)絡冗余設計避免網(wǎng)絡組件單點失效造成應用失效
B.通常情況下主路徑與備用路徑承擔相同的網(wǎng)絡負載
C.負載分擔是通過并行鏈路提供流量分擔來提高性能
D.網(wǎng)絡中存在備用鏈路時，可以考慮加入負載分擔設計
答案解析與討論：www.ichunya.com/st/4189616038.html

第62題： 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
答案解析與討論：www.ichunya.com/st/4189813956.html