ThedataacquisitionsystemfortheCMSexperimentattheLargeHadronCollider(LHC)willrequirealargeandhighperformanceeventbuildingnetwork.Severalarchitecturesandswithchtechnologiesarecurrentlybeingevaluated.Thispaperdescribesdemonstratorswhichhavebeensetuptostudyasmall-scaleeventbuilderbasedonPCsemulatinghighperformancesourcesandsinksconnectedviaEthernetorMyrinetswitches.Resultsfromongoingstudies,includingmeasurementsonthroughputandscaling,arepresented.
