CongestioncontrolforpacketssentonanetworkisimportantforDAQsystemsthatcontainaneventbuilderusingswitchingnetworktechnologies.QualityofService(QoS)isatechniqueforcongestioncontrol.RecentLinuxreleasesprovideQoSinthekerneltomanagenetworktraffic.Wehaveanalyzedthepacket-lossandpacketdistributionfortheeventbuilderprototypeoftheAtlasTDAQsystem.WeusedPC/LinuxwithGigabitEthernetnetworkasthetestbed.TheresultshowedthatQoSusingCBQandTBFeliminatedpacketlossonUDP/IPtransferwhiletheUDP/IPtransferinbesteffortmadelotsofpacketloss.TheresultalsoshowedthattheQoSoverheadwassmall.WeconcludedthatQoSonLinuxperformedefficientlyinTCP/IPandUDP/IPandwillhaveanimportantroleoftheAtlasTDAQsystem.
