Round-Trip Time

In telecommunications, the term round-trip delay time or round-trip time (RTT) has the following meanings: The elapsed time for transit of a signal over a closed circuit, or time elapsed for a message to a remote place and back again.In primary or secondary radar systems, the time required for a transmitted pulse to reach a target and for the echo or transponder reply to return to the receiver.
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(RTT) A measure of the current delay on a network, found by timing a packet bounced off some remote host. This can be done with ping -s.
(1994-11-30)