说明：  The ns Manual (formerly ns Notes and Documentation)1 The VINT Project A Collaboration between researchers at UC Berkeley, LBL, USC/ISI, and Xerox PARC. Kevin Fall 􀀀 kfall@ee.lbl.gov
, Editor Kannan Varadhan 􀀀 kannan@catarina.usc.edu
, Editor April 14, 2002 ns