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Spirent KB Article
Doc ID: FAQ14634
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Spirent TestCenter: How does RFC 2889 forward pressure rate testing work?
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The forward pressure test overloads a DUT/SUT port and measures the output for forward pressure. If the DUT/SUT transmits with an interframe gap less than 96 bits, then forward pressure is detected.
The forward pressure, stresses the DUT by sending it traffic at higher than wire rate load, using an interframe gap of 88 bits when the IEEE 802.3 standard allows for no less than 96 bits. The DUT, on the egress port, should properly transmit per the standard with a 96-bit interfame gap. If the DUT transmits at less than 96 bits, then forward pressure is detected and must be reported.
Switches that transmit with less than a 96-bit interframe gap violate the IEEE 802.3 standard and gain an unfair advantage over other devices on the network. Other switches may not interoperate properly with the switch in violation.
Product : RFC 2889