Zte ZXR10 5900E Series - Figure 2 Qinq Typical Networking; Qinq; Subnet VLAN

ZXR105900ESeriesUserManual(EthernetSwitchingVolume)
QinQ
QinQ,alsoknownasVLANstack,isagraphicnamefortheIEEE
802.1Qbasedtunnelprotocol.QinQtechnologyencapsulatesthe
originalVLANtag(innertag)withanotherVLANtag(outertag)so
thattheinnertagismasked.
QinQimplementssimpleLayer2VPN(L2VPN)withoutprotocol
support,applicabletosmall-sizedLANswithL3switchesastheir
core.
QinQtypicalnetworkingisshowninFigure2.Porttothecus-
tomernetworkiscalledthecustomerport.TheporttotheService
Providernetworkiscalledtheuplinkport,andtheSPedgeaccess
deviceiscalledPoviderEdge(PE).
FIGURE2QINQTYPICALNETWORKING
ThecustomernetworkisusuallyconnectedtothePEthroughtrunk
VLAN.UplinksportsintheSPnetworkareconnectedsymmetri-
callyinthetrunkVLANmode.
Whenapacket(tagged/untagged)fromcustomernetwork1
reachesthecustomerportofswitchA.SwitchAattachesanouter
tag(VLANIDas10)toitsforcibly.WithintheSPnetwork,packet
isforwardedtoallportsinVLAN10.Thispacketnallyarrivesat
switchB.SwitchBrecognizesthattheporttocustomernetwork
2isacustomerport,thendispatchestheoutertagcomplying
withthetraditional802.1Qtorestoretheoriginalpacket.Switch
Bsendsthepackettocustomernetwork2.
Thusdataistransparentlytransmittedbetweencustomernet-
works1and2throughtheSPnetwork.Thisallowsthecustomer
considerableexibilityforPrivateVLANIDplanning,withoutany
conictwiththoseoftheSPnetwork.
SubnetVLAN
Subnet-basedVLANappliestoL2VLANnetworksforexiblecon-
gurationofdataframeforwarding.Subnet-basedVLANforward
adataframetoaVLANbasedonthesourceIPaddress.This
sourceIPaddressbasedVLANcanforwarduserdatafromdiffer-
entsubnetscrossseveralVLANs,whileremaintheoriginalVLAN
membershipunchanged.
4CondentialandProprietaryInformationofZTECORPORATION