Zte ZXR10 ZSR V2 - Configuring Public IP Multicast

Chapter15NetworkLayerDetection
1100.0.0.2255ms2ms2ms
/*TheIPaddressonthefirst-hopdeviceandtimedelays*/
210.17.94.81176ms143ms333ms
310.28.5.61131ms133ms134ms
4***
/*Thefourth-hopdevicedoesnotreturnanypacket.Thereare"*"marks.*/
5202.70.62.169151ms149ms146ms
6202.43.177.81176ms162ms165ms
7218.100.27.30142ms134ms159ms
8175.103.59.110140ms166ms138ms
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15.7ConguringLSPPing
Overview
lDescriptionofLSPPing
OnanMPLSnetwork,ifIPpingisused,labelsareaddedtopingpacketsandlabel
switchingisperformed.IPping,however,onlychecksconnectivityontheIPplane,
butcannotcheckLSPs.OnanMPLSnetwork,ifaLDPsessionbetweentwoLSRsis
disconnected,labelscannotbeforwarded.Inthiscase,IPpingpacketsarereachable,
buttheLSPfails.
VariousfactorscauseLSPfaults.Forexample,anLDPsessionisdisconnected,LDP
isnotenabledonsomeLSRs,oranexceptionoccursinanLDPlabelforwardingtable.
AmechanismdifferentfromIPpingisneededtodetectwhetheranend-to-endLSP
isoperatingproperly.Therefore,LSPpingisgenerated.
LSPpingusesapacketbelongingtoaspecicForwardingEquivalenceClass
(FEC)toverifytheintegrityoftheLSP(fromthesourceLSRtothedestinationLSR)
thatbelongstothisFEC.AnLSPpingrequestpacketcontainsinformationonthe
correspondingFEC.
lWorkFlowofLSPPing
AnLSPpingpacketisencapsulatedinaUDPpacket,andcontainsaserialnumber
andatimestamp.WhenprocessinganLSPpingrequestpacket,MPLSusesthe
sameforwardingpolicyaspacketsoftheFEC.WhentheLSPpingpacketreaches
anLSPegress,theLSRcontrolplanechecksthepackettoverifywhetherthisLSPis
thecorrectegressoftheFEC.
SimilartoIPping,LSPpingalsousestheEchoRequestandEchoReplymechanism.
ButtheLSPpingpacketformatiscompletelydifferentfromtheIPpingpacketformat.
PacketssentbyLSPpingarenotICMPpacketsbutUDPpacketswhoseportnumber
is3503.OnanMPLSnetwork,
1.AsourcedevicesendsaUDPEchoRequestpacketwhoseportnumberis3503.
2.LSRsforwardtheEchoRequestpacketthroughlabelswitching.
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SJ-20140504150128-007|2014-05-10(R1.0)ZTEProprietaryandCondential