Zte ZXR10 5900E Series - Figure 8 STP before MAX_AGE Timer Expired

Chapter5STPConguration
packetandshutdowntheportwhichconnectstoswitchD.This
solvestheproblemofnetworkperformance.
PortLoopback
Protection
Function
Loopbackprotectionprovidesaddtionallayer2protectionfunction.
OnereasonforSTPlooptakesplacesinanetworkwithredundant
linkisthatoneportwhichinblockingstatebecomesadesignated
portandentersintoFORWARDINGstate.Ablockingportwhen
doesn’treceiveaBPDUpacket.STPthinksthatthereisn’taloop.
PortwilltransmitfromBLOCKINGstatetoFORWARDINGstate,
thiswillcreatealoop.
Whenportloopbackprotectionisconguredandblockingport
don’treceiveBPDUpacket.PortwilltransmitintoLOOP_INCON-
SISTENTstate.Thisstateisblockingstateanditdoesn’ttransmit
anydata.
FIGURE8STPBEFOREMAX_AGETIMEREXPIRED
InFigure8,switchAisarootswitch.Thereislinkfailurebetween
switchBandswitchCwhichdoesn’treceiveanyBPDUpacketfrom
switchB.BeforeMAX_AGEtimerexpired,portinswitchCisstill
inblockingstate.
CondentialandProprietaryInformationofZTECORPORATION41