作者skipandsnow (屁超)
看板Grad-ProbAsk
标题[商管] [计概]95中山资管
时间Fri Oct 9 10:01:08 2009
题目连结在此
http://www.lib.nsysu.edu.tw/exam/master/mana/infom/95.pdf
问答题第5题
[15 points] To find out how much slow start limits throughput on an 4Mbps
Ethernet connection(MTU = 10Kbits), we assume that a round-trip delay of 4
milliseconds and packets are send in MTU. Calculate the throughput of the
first 32 packets sent by using (A)[5 points] without slow start(B)[10 points]
slow start.
解答上是写
传递 32 packets 所需要的频宽是32*10Kbit = 320Kbits < 4Mbps, 所以32个 packets
可以一次送出, 并在一个RTT後得到所有ACK, 因此throughput = 32 packets / 4ms =
8000 packets/second.
想请问为什麽32 packets可以一次送出
网路卡传到网路线的时间不用计算在内吗?
我的想法是320Kbits / 4Mbps = 80 ms
throughput = 32 packets / (80 + 4)ms = 381 packets / second.
不过感觉数据差很多 小弟才疏学浅希望各位能帮我解答
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