After tags are terminated on the PEs, packets are sent to the carrier IP or MPLS network. To ensure inclusion of all the required Quality of Service (QoS) information in the packets, the 802.1p values in outer and inner tags must be mapped to the DSCP fields or the EXP fields.
QinQ VLAN tag termination can be used to implement the 802.1p and DSCP remark.
Relevant standards specify that the six bits of the Type of Service (ToS) field in an IPv4 packet header serve as the DiffServ Code Point (DSCP). DSCP provides a reference for differentiated services (DiffServ) and is used for QoS guarantee on the IP network.
With QinQ VLAN tag termination, a tagged packet is terminated on the PE before it is sent to the carrier IP network. In this scenario, you need to configure the mapping relationship between the 802.1p values in outer and inner tags and the DSCP field to ensure that all the required QoS information is included in the packet.
QinQ VLAN tag termination can be used to implement the 802.1p and EXP remark.
The EXP field in an MPLS packet is used for Class of Service (CoS) to implement traffic control on the gateway.
With QinQ VLAN tag termination, a tagged packet is terminated on the PE before it is sent to the carrier MPLS network. In this scenario, you need to configure the mapping relationship between the 802.1p values in outer and inner tags and the EXP field to ensure that all the required QoS information is included in the packet.
Before you configure a VLAN tag termination sub-interface to transmit IP services, plan user VLANs so that packets received by the VLAN tag termination sub-interface carry one or two VLAN tags.
The system view is displayed.
The view of an Ethernet sub-interface on the user side of a PE is displayed.
QinQ termination is configured as the encapsulation type of the sub-interface.
The VLAN tag termination function is configured for the QinQ VLAN tag termination sub-interface.
After you specify rt-protocol, the sub-interface terminates double-tagged packets, and both inner and outer tags must be specific VLAN IDs.
After a QinQ VLAN tag termination sub-interface is configured to support 802.1p mapping, run the display qinq information termination [ interface interface-type interface-number [ .subinterface-number ] ] command on the PE to check detailed configurations on the QinQ VLAN tag termination sub-interface.