第8題： 關(guān)于無線網(wǎng)絡(luò)中使用的擴(kuò)頻技術(shù)，下面描述中錯誤的是（ ）。
A.用不同的頻率傳播信號擴(kuò)大了通信的范圍
B.擴(kuò)頻通信減少了干擾并有利于通信保密
C.每一個信號比特可以用N個碼片比特來傳輸
D.信號散布到更寬的頻帶上降低了信道阻塞的概率
答案解析與討論：www.yifanwine.com/st/2344326034.html

第9題： 物聯(lián)網(wǎng)中使用的無線傳感網(wǎng)絡(luò)技術(shù)是（ ）。
A.802.15.1藍(lán)牙個域網(wǎng)
B.802.11n無線局域網(wǎng)
C.802.15.3 ZigBee微微網(wǎng)
D.802.16m無線城域網(wǎng)
答案解析與討論：www.yifanwine.com/st/2344422058.html

第10題： 正在發(fā)展的第四代無線通信技術(shù)推出了多個標(biāo)準(zhǔn)，下面的選項中不屬于4G標(biāo)準(zhǔn)的是（ ）。
A.LTE
B.WiMAXII
C.WCDMA
D.UMB
答案解析與討論：www.yifanwine.com/st/2344516479.html

第12題： 網(wǎng)絡(luò)系統(tǒng)設(shè)計過程中，物理網(wǎng)絡(luò)設(shè)計階段的仟務(wù)是（ ）。
A.依據(jù)邏輯網(wǎng)絡(luò)設(shè)計的要求，確定設(shè)備的具體物理分布和運(yùn)行環(huán)境
B.分析現(xiàn)有網(wǎng)絡(luò)和新網(wǎng)絡(luò)的各類資源分布，掌握網(wǎng)絡(luò)的狀杰
C.根據(jù)需求規(guī)范和通信規(guī)范，實施資源分配和安全規(guī)劃
D.理解網(wǎng)絡(luò)應(yīng)該具有的功能和性能，最終設(shè)計出符合用戶需求的網(wǎng)絡(luò)
答案解析與討論：www.yifanwine.com/st/2344716661.html

第13題： 下列關(guān)于網(wǎng)絡(luò)核心層的描述中，正確的是（ ）。
A.為了保障安全性，應(yīng)該對分組進(jìn)行盡可能多的處理
B.將數(shù)據(jù)分組從一個區(qū)域高速地轉(zhuǎn)發(fā)到另一個區(qū)域
C.由多臺二、三層交換機(jī)組成
D.提供多條路徑來緩解通信瓶頸
答案解析與討論：www.yifanwine.com/st/2344811789.html

第14題： Let us now see how randomization is done when a collision occurs . After a (1), time is divided into discrete slots whose length is equal to the worst-case round-trip propagation time on ether. To accommodate the longest path allowed by Ethernet, the slot time has been set to 512 bit times, or 51.2us.
After the first collision, each station waits either 0 or 1 (2) times before trying again. If two stations collide and each one picks the same random number, they will collide again. After the second collision, each one picks either 0,1,2 or 3 at random and waits that number of slot times. If a third collision occurs (the probability of this happening is 0.25), then the next time the number of slots to wait is chosen at (3) from the interval 0 to 23-1.
In general, after I collisions, a random number between 0 and 2i -1 is chosen, and that number of slots is skipped. However, after ten collisions have been reached, the randomization (4) is frozen at a maximum of 1023 slots. After 16 collisions, the controller throws in the towel and reports failure back to the computer. Further recoveries up to (5) layers.

（1）A.datagram
 B.collision
 C.connection
D.service
（2）A.slot
 B.switch
 C.process
 D.fire
（3）A.rest
 B.random
 C.once
 D.odds
（4）A.unicast
 B.multicast
 C.broadcast
 D.interval
（5）A.local
 B.next
 C.higher
 D.lower

答案解析與討論：www.yifanwine.com/st/2344912465.html