Recommendation on using the "gentle_" variant of RED

For the best behavior of RED in simulations and in implementations, my advice would be to implement RED, and to run simulations, with the "gentle_" parameter set to 1. In the "gentle_" modification to RED in NS, the packet-dropping probability varies from "max_p" to 1 as the average queue size varies from "maxthresh" to twice "maxthresh". This option makes RED much more robust to the setting of the parameters "maxthresh" and "max_p", and was added to NS on 6/12/99.

- Sally Floyd, March 3, 2000.

The "gentle_" parameter can be set in the NS simulator with the following command:
Queue/RED set gentle_ true

For backwards-compatibility reasons, I have left the default value of the gentle_ parameter in NS as false.

The "gentle_" variant of RED was implemented for an ATM switch, and evaluated, in the following paper:

Return to [ Sally Floyd].
Last modified: March 2000