简介:MPLS(Multi-ProtocolLabelSwitching)VPN(VirtualPrivateNetwork)traffichasbeendeployedwidely,butcurrentlyonlysupportsunicast.ThispaperbrieflyintroducesseveralavailableMPLSVPNmulticastapproaches,andthenanalyzestheirdisadvantages.Anovelmechanismthatusestwo-layerlabelstacktosupportMPLSVPNexplicitmulticastisproposedandtheprocessisdiscussedindetail.Thescalabilityandperformanceoftheproposedmechanismarestudiedanalytically.Theresultshowsthatoursolutionhasgreatadvantageoverthecurrentlyavailableschemeintermsofsavingcorenetworkbandwidthandimprovingthescalability.
简介:Multi-protocollabelswitching(MPLS)hastheadvantageofhighefficiencyinthesecondlayer,whichimprovestheperformanceofdatapacketsrouting.Inthispaper,anewstructuretoimplementopticalMPLSisproposed.Weconstructacodefamilyforspectral-amplitudecoding(SAC)labelsintheopticalMPLSnetworks.SAClabelsaresuitableforopticalpacketswitchingbecausetheycanbeconstructedandrecognizedquicklyateachrouter.Weusethelabelstackingtoprovidehierarchicalroutingtoavoidswappinglabelsateachforwardingnodeandreducesystemcomplexity.However,thephase-inducedintensitynoise(PIIN)appearsduetotheincoherentpropertyofthelightsourcewhenthestackedlabelssetmakesthecorrelationdecodingwiththelocalnodelabel,whichdegradessystemperformance.