A.信號(hào)B.數(shù)據(jù)C.信道D.信宿
A.非堅(jiān)持CSMAB.1-堅(jiān)持CSMAC.P-堅(jiān)持CSMAD.堅(jiān)持CSMA
A.檢錯(cuò)重發(fā)B.向后糾錯(cuò)C.反饋校驗(yàn)D.檢錯(cuò)丟棄