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round-trip time

How long a message takes to get there and for the reply to come back.

Round-trip time is the delay from sending a message to receiving its response; TCP's retransmission timeout and every request/response protocol depend on it.

Examples

  • ping from the laptop to the router measures round-trip time: send a small packet, time how long the reply takes.

  • With a 5 ms round trip, sending 1,000 readings one at a time and waiting for each reply takes 5 seconds.

See also

latency throughput retransmission
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