The wfq and wf2q+ implementations are in the following links. http://www.pao.lombardiacom.it/wfq.html http://www.cs.cmu.edu/%7Echeeko/wf2q+/ After I downloaded the files and installed in ns-2.1b6 but I can't get them to work. Can anyone give me hints or help on this. Thanks Hong Kong Polytechnics University Electronic and Information Engineer Network Research Team