Meshtopology
ConnectmultiplesubnetsormultiplenetworkstoformanInternettopology.Inasubnet,hubsandrepeatersconnectmultipledevices,whilebridges,routers,andgatewaysconnectthesubnets.Accordingtodifferentnetworkinghardware,therearethreemainInternettopologies:
Meshnetwork
Inalargearea,whenalarge-scalenetworkisconnectedbyaradiocommunicationlink,themeshnetworkIsthebesttopology.Therouterisconnectedtotherouter,allowingthenetworktochoosethefastestpathtotransmitdata.
Backbonenetwork
ConnectdifferentsubnetsorLANsthroughbridgesandrouterstoformasinglebusorringtopology.Thiskindofnetworkusuallyusesopticalfibersasthebackbone.
Starconnectionnetwork
Usingsomedevicescalledsuperhubstoconnectthenetwork,duetothecharacteristicsofthestarstructure,anyfaultinthenetworkcanbeeasilyfoundandrepaired.
Polygonnetworktopology
Advantagesofmeshtopology
(1)Networkreliabilityishigh,generallybetweenanytwonodeswitchesinthecommunicationsubnet,Therearetwoormorecommunicationpaths,sothatwhenonepathfails,theinformationcanalsobesenttothenodeswitchthroughtheotherpath.
(2)Thenetworkcanbebuiltintovariousshapes,usingmultiplecommunicationchannelsandmultipletransmissionrates.
(3)Itiseasyfornodesinthenetworktoshareresources.
(4)Canimprovetheinformationflowdistributionofthecircuit.
(5)Thebestpathcanbeselectedandthetransmissiondelayissmall.
Disadvantagesofmeshtopology
(1)Complexcontrolandcomplexsoftware.
(2)Thelinecostishighanditisnoteasytoexpand.
(3)IntheEthernet,ifthesettingisimproper,itwillcauseabroadcaststorm,andinseverecases,thenetworkcanbecompletelyparalyzed.
MeshtopologyisgenerallyusedonInternetbackbonenetworks,androutingalgorithmsareusedtocalculatethebestpathforsendingdata.