Radwin 2000 - Protection Switching; Hardware Considerations

RADWIN2000UserManual Release2.8.30 16‐6
ProtectionSwitching
ProtectionSwitching
Protectionswitchingoccursuponfailureinthering.
TheEthernetservicerestorationtimedependsonthenumberofhopsinthering.Withfour
hopstheEthernetserviceisrestoredinlessthan50ms.
Insingleanddualhomedtopologiestheservicerestorationmaytakelongerduetotheaging
timeoftheexternalswitches.Switchesthatareimmediatelyawareofroutingchangesreduce
therestorationtime.
HardwareConsiderations
EthernetRingProtectionissupportedbythe IDU‐C,IDU‐EandPoE.
AtypicalRingProtectionLinkconsistsofanIDU‐CorIDU‐E,aPoEandtwoODUsasshownin
Figure16‐2.HenceoneendoftheRPLandofringcontrolledlinks,asshowninFigure16‐2
hastobeanIDU.Itisre commendedtohaveanIDUateachnodetohavetheflexibi lityto
changetheRPL.
AringnodeisbuiltfromtwoODUsfromadjacentlinks.TheODUscanbeconnectedtoeither
anIDUortoaPoEdeviceasinFigure16‐2.PortnamesintheIDUareshown.
Sharedring
RADWINringswithsharedhops.
Note:
•ARADWINlinkhopcanbeapartofupto4rings
•TheRPLcannotbeasharedlink
•ThetwoRPLsshouldusedifferentMinimumTime
forActivationvaluestopreventduplicateaction
causingaloop
Table16‐1:TopologiessupportedbyRADWINEthernetRing(Continued)