R3303-HP HSR6800 Routers Layer 2 - LAN Switching Configuration Guide

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Figure 68 One-to-one VLAN mapping implementation
Many-to-one VLAN mapping
Implement many-to-one VLAN mapping through the following configurations, as shown in Figure 69:
• Apply an uplink policy to incoming traffic on the customer-side port to map different CVLAN IDs to
one SVLAN ID. When a packet arrives, the switch replaces its CVLAN tag with the matching SVLAN
tag.
• Configure the network-side port as a DHCP snooping trusted port. For downlink traffic, the switch
looks through the DHCP snooping table, and replaces the SVLAN ID with the CVLAN ID found in
the table.
Figure 69 Many-to-one VLAN mapping implementation
Each DHCP snooping entry contains information about one DHCP client, including its IP address, MAC
address, and CVLAN. For more information about DHCP snooping, see Layer 3—IP Services
Configuration Guide.
One-to-two VLAN mapping
Implement one-to-two VLAN mapping through the following configurations, as shown in Figure 70:
• Apply an uplink policy to incoming traffic on the customer-side port to tag incoming packets from a
certain CVLAN with an outer SVLAN tag.
• Configure the customer-side port as a hybrid port, and assign the port to SVLANs as an untagged
member. When the port forwards packets from these SVLANs, it removes their SVLAN tag.
Customer
network
SP network
DataSVLAN
DataSVLAN
DataCVLAN
Inbound
uplink policy
DHCP snooping table lookup
CVLAN n Data
CVLAN 1 Data
Network-side
port
Customer-side
port
Uplink traffic Downlink traffic
DataSVLAN