H3C S6850 Series Configuration Guide

2
As shown in Figure 2, customer A has remote sites CE 1 and CE 4. Customer B has remote sites CE
2 and CE 3. The CVLANs of the two customers overlap. The service provider assigns SVLANs 3 and
4 to customers A and B, respectively.
When a tagged Ethernet frame from CE 1 arrives at PE 1, the PE tags the frame with SVLAN 3. The
double-tagged Ethernet frame travels over the service provider network until it arrives at PE 2. PE 2
removes the SVLAN tag of the frame, and then sends the frame to CE 4.
Figure 2 Typical QinQ application scenario
QinQ implementations
QinQ is enabled on a per-port basis. The link type of a QinQ-enabled port can be access, hybrid, or
trunk. The QinQ tagging behaviors are the same across these types of ports.
A QinQ-enabled port tags all incoming frames (tagged or untagged) with the PVID tag.
• If an incoming frame already has one tag, it becomes a double-tagged frame.
• If the frame does not have any 802.1Q tags, it becomes a frame tagged with the PVID.
QinQ provides the most basic VLAN manipulation method to tag all incoming frames (tagged or
untagged) with the PVID tag. To perform advanced VLAN manipulations, use VLAN mappings or
QoS policies as follows:
• To add different SVLANs for different CVLAN tags, use one-to-two VLAN mappings.
• To replace the SVLAN ID, CVLAN ID, or both IDs for an incoming double-tagged frame, use
two-to-two VLAN mappings.
• To use criteria other than the CVLAN ID to match packets for SVLAN tagging, use the QoS nest
action. The QoS nest action can also be used with other actions in the same traffic behavior.
• To set the 802.1p priority in SVLAN tags, use the priority marking action as described in "Setting
the 802.1p p
riority in SVLAN tags."
For more information about VLAN mappings, see "Configuring VLAN mapping." For more
information about QoS, see ACL and QoS Configuration Guide.
PE 1
Service provider network
Internet
PE 2
VLANs 1 to 20
Customer
network B
CE 3
Customer
network A
VLANs 1 to 10
CE 1
VLANs 1 to 10
Customer
network A
CE 4
VLANs 1 to 20
Customer
network B
CE 2
DataSVLAN 4 CVLAN B
DataSVLAN 3 CVLAN A DataSVLAN 4 CVLAN B
DataSVLAN 3 CVLAN A
DataCVLAN B
DataCVLAN BDataCVLAN A
DataCVLAN A

H3C S6850 Series Specifications

General

Brand	H3C
Model	S6850 Series
Category	Switch
Language	English