Radwin 2000 - Figure 17-1 Two Network; Figure 17-2 Separating Client

RADWIN2000UserManual Release2.8.30 17‐2
QinQ(DoubleTagging)forServiceProviders
Figure17‐1:Twonetworkusingthesamelinkwithtagging
IEEE802.1Qisusedastheencapsulation protocoltoimplementthismechanismover
Ethernetnetworks.
QinQ(DoubleTagging)forServiceProviders
QinQisusefulforServiceProviders,allowingthemtouseVLANsinternallyintheir“transport
network”whilemixingEthernettrafficfromclientsthatarealreadyVLAN‐tagged.
Figure17‐2:Separatingclientdatastreamsusingdoubletagging
Theoutertag(representingtheProviderVLAN)comesfirst,followedbytheinnertag.InQinQ
theEtherType=0x9100.VLANtagsmaybestackedthreeormoredeep.
Whenusingthistypeof“Provider Tagging ”youshouldkeepthefollowinginmind:
• UnderProviderTagging,thesystemdouble‐tagsegre ssframestowardstheProvider’s
network.ThesystemaddsatagwithaVLANIDandEtherT ype=0x9100toallframes,as
configuredbytheserviceprovider(ProviderVLANID).
• Thesystemalwaysaddstoeachframe,tagswithVLANIDandEtherT ype=0x9100.
Therefore,
• Foraframewithoutatag–thesystemwilladdatagwithVLANIDandEtherType=
0x9100sotheframewillhaveonetag