User manual

 16‐PortGigabitEthernetPoE+Web‐ManagedSwitchwith2SFPPorts
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EachportonaswitchusingSTPexistsisinoneofthefollowingfivestates:
 Blocking–theportisblockedfromforwardingorreceivingpackets
 Listening–theportiswaitingtoreceiveBPDUpacketsthatmaytelltheporttogobacktotheblockingstate
 Learning–theportisaddingaddressestoitsforwardingdatabase,butnotyetforwardingpackets
 Forwarding–theportisforwardingpackets
 Disabled–theportonlyrespondstonetworkmanagementmessagesandmustreturntotheblockingstatefirst
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Aporttransitionsfromonestatetoanotherasfollows:
 Frominitialization(switchboot)toblocking
 Fromblockingtolisteningortodisabled
 Fromlisteningtolearningortodisabled
 Fromlearningtoforwardingortodisabled
 Fromforwardingtodisabled
 Fromdisabledtoblocking
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It'spossibletomodifyeachportstatebyusingmanagementsoftware.WhenyouenableSTP,everyportoneveryswitch
inthenetworkgoesthroughtheblockingstateandthentransitionsthroughthestatesoflisteningandlearningatpower
up.Ifproperlyconfigured,eachportstabilizestotheforwardingorblockingstate.Nopackets(exceptBPDUs)are
forwardedfromorreceivedbySTPenabledports,untiltheforwardingstateisenabledforthatport.
TheSwitchallowsfortwolevelsofoperation:theswitchlevelandtheportlevel.Theswitchlevelformsaspanningtree
consistingoflinksbetweenoneormoreswitches.Theportlevelconstructsaspanningtreeconsistingofgroupsofone
ormoreports.TheSTPoperatesinmuchthesamewayforbothlevels.
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