Qinq Frame Structure - HP 6600 Configuration Manual

Figure 49 Typical QinQ application scenario
VLANs 1 to 20
Customer
network B
PE 1
Customer
network A
VLANs 1 to 10
As shown in
CVLANs 1 through 20. The service provider assigns SVLAN 3 for customer network A, and assigns
SVLAN 4 for customer network B.
When a tagged Ethernet frame from customer network A arrives at a PE, the PE tags the frame with outer
VLAN 3. When a tagged Ethernet frame from customer network B arrives at a PE, the PE tags the frame
with outer VLAN 4. No overlap of VLAN IDs among customers exists, and traffic from different customers
can be identified separately.
The double-tagged Ethernet frame is then transmitted over the service provider network and arrives at the
other PE. The PE removes the SVLAN tag from the frame before sending it to the target CE.

QinQ frame structure

A QinQ frame is transmitted double-tagged over the service provider network. As shown in
the inner VLAN tag is the CVLAN tag, and the outer one is the SVLAN tag that the service provider has
allocated to the customer.
QinQ uses CVLAN tags to transmit frames over a private network, and uses SVLAN tags to transmit
frames over a public network. When a QinQ frame is transmitted over a public network, its CVLAN tag
is transmitted as part of the payload.
CE 3
VLAN 4
VLAN 3
CE 1
Figure 49, customer network A has CVLANs 1 through 10, and customer network B has
IP network
Public network
143
VLANs 1 to 10
CE 4
Customer
network A
VLAN 3
PE 2
VLAN 4
Customer
network B
CE 2
VLANs 1 to 20
Figure 50,