User's Manual

CHAPTER7
BRIDGELINKSANDMESH
Revised: 09 Aug 2016 7-3 ESTeem Horizon Series
RapidSpanningTreeProtocol(RSTP)
TheESTeemHor i zonusesstandardEthernetRapidSpanningTreeProtocol(RSTP)todeterminetheradioroutingstructureofthe
wirelessnetwork.TheprimarypurposeofRSTPistomakesurethat“networkloops”arenotcreated.Anetworkloopishaving
twocommunicationpathstothesa
medestinationwheretheremotedevicewouldreceivethesamedatamultipletimes.Ifthere
werenowaytocontrolthedataflow , thisdat awouldbeconstantlypassedaroundthisloopcausinga“packetstorm”thatwoul d
shutdowntheentirenetwork.TheSpanningTreeProtocolwillblockallth
eseredundantlinks.
TheRSTPoperationbeginsbydeterminingwhichEthernetdeviceonthenetworkwillbetheRootBridge.AllEthernetnetworks
haveaRootBridgethatisselectedbythelowestMACaddress.AllpathlengthsareevaluatedagainstthisRootBridgedeviceto
determineroutingandwhichpathswi
llbeblocked.OnawiredEthernetnetwork,thelocationoftheRootBridgeisnotreally
important,butinawirelessnetwork selectionoftheRootBridgeiscriticaltothewirelessnetworkrouting.Let’suseoneofthe
ExamplenetworkdiagramsfromChapter3tocontinuethediscussion(Fig
ure4).
Figure4:ProgrammingExample#1Diagram
Access Point Router
with Repeater
Feature Enabled
10/100BaseT
HUB or Switch
Mobile
PLC
EtherStation
Mode
10/100BaseT
Access Point Bridge
with Repeater
Feature Enabled
P
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Access Point Bridge
with Repeater
Feature Enabled
Mobile Vehicle
Single Ethernet Device
Example #4
S/N: 14004
P
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Re
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Plant Network
Large Wired LAN
Example #1
S/N: E-14001
WLAN MAC=00:04:3F:00:09:01
Remote Building
Small Ethernet Wired LAN
Example #3
S/N: E-14003
WLAN MAC=00:04:3F:00:09:10
Stand-Alone Repeater Site
Example #2
S/N: E-14002
WLAN MAC= 00:04:3F:00:09:05
Network
Router
(Required)