In low-speed network,it is usually adequate to wait for congestion to occur and then react to it by telling the source of packets to slow down.In high-speed networks,this approach often works poorly,because in the（71）between sending the notification and notification arriving at the source,thousands of additional（72）may arrive.In ATM network,a major tool for preventing（73）is（74）control.When a host wants a new virtual（75）,it must describe the traffic to be offered and the service expected.A.flowB.admissionC.trafficD.time
In low-speed network,it is usually adequate to wait for congestion to occur and then react to it by telling the source of packets to slow down.In high-speed networks,this approach often works poorly,because in the（71）between sending the notification and notification arriving at the source,thousands of additional（72）may arrive.In ATM network,a major tool for preventing（73）is（74）control.When a host wants a new virtual（75）,it must describe the traffic to be offered and the service expected.
A.flow
B.admission
C.traffic
D.time
B.admission
C.traffic
D.time
参考解析
解析：在低速网络中，通常采用碰到拥塞时，通过向源端反映使其降低发送速率。而在告诉网络中，这种方式将会恶化，因为在发送通告和通告到达之间会有成千上万的其它数据包到达。在ATM网络中，主要采用允许控制来避免拥塞，当有一台主机要建立一条新的虚连接时，它必须描述它所需的流量和服务等级。
相关考题：
根据下面的文字资料回答 66～70 题In low-speed network，it is usually adequate to wait for congestion to occur andthen react to it by telling the source of packets to slow down．In high-speednetworks，this approach oftenworks poorly，because in the（ 1 ）between sending thenotification and notification arriving at the source，thousands ofadditional（ 2 ）may aITive．In ATM network，a major tool forpreventing（ 3 ）is（ 4 ）control．when a host wants a new virtual（ 5 ），it mustdescribe the traffic to be offered and the service expected．第66题：文中（ 1 ）处正确的答案是（ ）。A．intervalB．timeC．slotD．delay
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