Zte ZXR10 5900E Series - Page 91

Chapter4IS-ISConguration
àAtleastoneneighborinUPstateisrequired.
àIfthestateofaneighborchanges,DISelectionisrequired.
àIftheLANIDintheIIHPDUcarriedbytheneighborchanges,DISelectionis
required.
BoththelocalrouterandotherrouterscanbeelectedastheDIS.Ifthelocalrouteris
electedastheDIS,theDISperformsthefollowingsteps:
1.IfotherISsexist,setthelifetimeofthepseudo-nodesto0anddeletethemonthe
network.
2.Generatenewpseudo-nodeLSPandperformooding.
3.Generatenewnonpseudo-nodeLSPandperformooding.
IfthelocalISdoesnotoperateastheDIS,performthefollowingsteps:
1.Setthelifetimeofthepseudo-nodesgeneratedbyitselfto0andperformooding
onthenetwork.
2.Generatenewnonpseudo-nodeLSPandperformooding.
Reliableoodingandlinkstatedatabasesynchronization
ThefollowingdescribesthefrequentlyusedtermsintheIS-IS:
lCSNP:CompleteSequenceNumbersProtocolDataUnit.
Itisusedtochecklinkstateconsistencyonbothpoint-to-pointlinksandbroadcast
links.
lPSNP:PartialSequenceNumbersProtocolDataUnit.
Itisusedto
àacknowledgethereceivedLSPonpoint-to-pointlinks.
àapplyforlatestversionorthelostLSP .
lSRM:SendRoutingMessage.
ItisusedtocontroltheLSPtotransmitmessagestoaneighborrouter.
lSSN:SendSequenceNumbersMessage.
Itisusedto
àacknowledgethereceivedLSPthatisoodedonpoint-to-pointlinks.
àapplyforthecompleteLSPinformationforsynchronizingthedatabaseon
broadcastlinks.
lTLV:Type/Length/Value.Type:Typeofaspeciedeld.Length:Lengthofaspecied
eld.Value:Informationcontents.
TheTLViscarriedinthePDUoftheIS-IS,andisusedtodescribetheextendable
elds.
TheCSNPandPSNPhavethesamepackageformat,andcarrytheLSPabstract
informationrespectively.ThedifferencebetweenthemisthattheCSNPadvertised
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SJ-20150114102049-003|2015-01-15(R1.0)ZTEProprietaryandCondential