Inlow-speednetwork,itisusuallyadequatetowaitforcongestiontooccurandthenreacttoitbytellingthesourceofpacketstoslowdown.Inhigh-speednetworks,thisapproachoftenworkspoorly,becauseinthe(71)betweensendingthenotificationandnotificationarrivingatthesource,thousandsofadditional(72)mayarrive.InATMnetwork,amajortoolforpreventing(73)is(74)control.Whenahostwantsanewvirtual(75),itmustdescribethetraffictobeofferedandtheserviceexpected.
A.flow B.admission C.traffic D.time正确答案C
