A.數(shù)據(jù)承載業(yè)務(wù) B.電視會(huì)議業(yè)務(wù) C.監(jiān)視圖像傳送業(yè)務(wù) D.數(shù)據(jù)終端業(yè)務(wù)
A.普通電話業(yè)務(wù) B.專用電話業(yè)務(wù) C.電話會(huì)議業(yè)務(wù) D.廣播業(yè)務(wù)