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Unless I'm wrong, they've measured both: Latency is 1 hour (time it takes a packet to go from source to destination), bandwidth is that number they quoted.


Latency is 1 hour, but to get bandwidth you need to divide not by 1 hour but by the time between successive station wagon departures. For example if you only have one station wagon and driving back after copying the tapes takes a further 30 minutes, then the denominator is 5400 seconds and so the system bandwidth is 50% less than the number quoted.


Latency is greater than 1 hour, if it takes an hour to copy the data to the tapes. You've got to get them to the destination and copy them off after that.


>If it takes an hour to copy a terabyte of data to a tape, put it in a car, drive to a location and read the tape

That's 1 hr latency, unless I'm mistaken. Latency doesn't include disk operations on the client side, does it? Is latency time between a signal being sent and received, or between sent, received, and acknowledgement sent/received?

ie, is latency time(client->SYN->server->SYNACK->client->ACK->server), or time(client->SYN->server)?


Bah. My reading comprehension not so good.




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