To forward packets with 2 or more tags using a QinQ SAP, a new Epipe service type is available for use when 7210 SAS devices are operating in ‛network’ mode. This new service allows for configuration of a QinQ SAP as one endpoint and the following service entities as the other endpoint:
MPLS spoke-SDP with vc-type set to vc-vlan: The VC VLAN tag to be must match the inner tag VLAN ID value specified in the QinQ SAP.
dot1q SAP: The VLAN value configured for the dot1q SAP must match the inner-tag VLAN ID value of the QinQ SAP.
QinQ SAP: The inner VLAN tag of both QinQ SAPs configured in the service must be the same.
The device processes the packet as follows in the forward direction:
If the packet is received on a QinQ SAP, assign an incoming packet to this service based on matching the outermost two tags in the packet header (that is, the first two tags in the packet header). It strips only the outermost tag (only a single tag) on ingress and forward the rest on to the other endpoint in the service (as follows).
If the other endpoint the packet is sent out of is a MPLS SDP, then MPLS encapsulation is added.
If the other endpoint the packet is sent out of is a dot1q SAP packet is forwarded as is, without any egress VLAN checks. The operator must ensure the inner tag of the packet matches the dot1q VLAN value.
If the other endpoint the packet is sent out of is another QinQ SAP (for example, Q1.Q2 SAP), then another tag (that is, Q2 tag) is added to the packet and sent out of the QinQ SAP.
In the reverse direction, the device processes the packet as follows:
When traffic is received on the MPLS SDP, the VC VLAN tag is retained as is and the VLAN tag corresponding to the outermost tag configured for the QinQ SAP (that is, the other endpoint) is added to the packet. The system does not match the VC VLAN tag received in the packet with the configured value (that is, the inner tag of the QinQ SAP). The operator must configure both ends of the service appropriately to ensure only appropriate packets enter the service.
When traffic is received on the dot1q SAP, the outermost tag is stripped and the VLAN tag corresponding to the outermost tag configured for the QinQ SAP is added to the packet.
If the packet is received on a QinQ SAP, assign an incoming packet to this service based on matching the outermost two tags in the packet header (that is, that is, the first two tags in the packet header). It strips only the outermost tag (only a single tag) on ingress. The VLAN tag corresponding to the outermost tag configured for the QinQ SAP (that is, the other endpoint) is added to the packet and it is sent out of the QinQ SAP.
Therefore, the device processes packets received with 2 or more tags using the MPLS SDP or a dot1q SAP while classifying on the QinQ SAP ingress using 2 tags.