● In multipoint networks , there are tree persistence methods when a station finds a channel busy.in the 1-persistent method,after the station finds the line idle,it sends its frame immediately.this method has the （  ） chance of collision because two or more stations may find the line （  ） and send their frames immediately. In the nonpersistent method , a station that has a frame to send （  ） the line . If the line is idle , it sends immediately If the line is not idle , it waits a （  ） amount of time and then senses the line again.The nonpersistent approach （  ） the chance of collision because it is unlikely that two or more stations will wait the same amount of time and retry to send simultaneously The p-persistent approach combines the advantages of the other two strategies . It reduces the chance of collision and improves efficiency.

（71）A．the lowest

B.the highest

C.possible

D.no

（72）A．idle

B.busy

C.useful

D.unusable

（73）A．overhears

B.hears

C.listens

D.senses

（74）A．random

B.big

C.medium

D.small

（75）A．increases

B.equalizes

C.reduces

D.cancels

相關(guān)推薦：2018下半年網(wǎng)絡(luò)管理員真題匯總

點擊注冊會員>>>即可獲取網(wǎng)絡(luò)管理員免費在線真題、觀看免費公開課！