第51題： OSPF協(xié)議將其管理的網(wǎng)絡(luò)劃分為不同類型的若干區(qū)域（Area），其中標(biāo)準(zhǔn)區(qū)域特點(diǎn)是（1）；存根區(qū)域（stub）的特點(diǎn)是（2）。
（1）A.不接受本地AS之外的路由信息，也不接受其他區(qū)域的路由匯總信息
B.不接受本地AS之外的路由信息，對(duì)本地AS之外的目標(biāo)采用默認(rèn)路由
C.可以接收任何鏈路更新信息和路由匯總信息
D.可以學(xué)習(xí)其他AS的路由信息，對(duì)本地AS中的其他區(qū)域采用默認(rèn)路由
（2）A.不接受本地AS之外的路由信息，也不接受其他區(qū)域的路由匯總信息
B.不接受本地AS之外的路由信息，對(duì)本地AS之外的目標(biāo)采用默認(rèn)路由
C.可以接收任何鏈路更新信息和路由匯總信息
D.可以學(xué)習(xí)其他AS的路由信息，對(duì)本地AS中的其他區(qū)域使用默認(rèn)路由
答案解析與討論：www.jycxcx.com/st/2383027389.html

第52題： NAT技術(shù)解決了IPv4地址短缺的問題，假設(shè)內(nèi)網(wǎng)的地址數(shù)是m，而外網(wǎng)地址數(shù)n，若m>n，則這種技術(shù)叫做（1），若m>n，且n=1，則這種技術(shù)這叫做（2）。
（1）A.動(dòng)態(tài)地址翻譯
B.靜態(tài)地址翻譯
C.地址偽裝
D.地址變換
（2）A.動(dòng)態(tài)地址翻譯
B.靜態(tài)地址翻譯
C.地址偽裝
D.地址變換
答案解析與討論：www.jycxcx.com/st/238318386.html

第53題： CIDR技術(shù)解決了路由縮放問題，例如2048個(gè)C類網(wǎng)絡(luò)組成一個(gè)地址塊，網(wǎng)絡(luò)號(hào)從192.24.0.0~192.31.255.0這樣的超網(wǎng)號(hào)應(yīng)為（1），其地址掩碼應(yīng)為（2）。
（1）A.192.24.0.0
B.192.31.255.0
C.192.31.0.0
D.192.24.255.0
（2）A.255.255.248.0
B.255.255.255.0
C.255.255.0.0
D.255.248.0.0
答案解析與討論：www.jycxcx.com/st/2383224030.html

第55題：

The traditional way of allocating a single channel among multiple competing users is to chop up its (1) by using one of the multiplexing schemes such as FDM (Frequency
Division Multiplexing). If there are N users, the bandwidth is divided into N equal-sized portions, with each user being assigned one portion. Since each user has a private frequency (2), there is no interference among users.When there is only a small and constant number of users, each of which has a steady stream or a heavy load of (3), this division is a simple and efficient allocation mechanism. A wireless example is FM radio stations. Each station gets a portion of the FM band and uses it most of the time to broadcast its signal.However, when the number of senders is large and varying or the traffic is (4), FDM presents some problems. If the spectrum is cut up into N regions while fewer than N users are currently interested in communicating, a large piece of valuable spectrum will be wasted. If more than N users want to communicate, some of them will be denied (5) for lack of bandwidth.??
（1）A.capability   
B.capacity   
C.ability  
D.power
（2）A.band   
B.range  
C.domain   
D.assignment
（3）A.traffic   
B.date   
C.bursty  
D.flow
（4）A.continuous   
B.steady   
C.bursty   
D.flow
（5）A.allowance  
B.connection   
C.percussion  
D.percussion

答案解析與討論：www.jycxcx.com/st/2383421378.html