Cisco IOS IP SLA Responder is a Cisco IOS Software component whose functionality is to respond
to Cisco IOS IP SLA request packets. The IP SLA source sends control packets before the operation
starts to establish a connection to the responder. Once the control packet is acknowledged, test
packets are sent to the responder. The responder inserts a time-stamp when it receives a
packet and factors out the destination processing time and adds time-stamps to the sent
packets. This feature allows the calculation of unidirectional packet loss, latency, and jitter
measurements with the kind of accuracy that is not possible with ping or other dedicated probe
testing.
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The IP SLAs responder is a component embedded in the destination Cisco device that allows the
system to anticipate and respond to IP SLAs request packets. The responder provides accurate
measurements without the need for dedicated probes.
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UDP Jitter measures the delay, delay variation(jitter), corruption, misorderingand packet lossby
generating periodic UDP traffic. This operation always requires IP SLA responder.