ZyXEL Communications 4728F User Manual

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XGS-4526/4528F/4728F User’s Guide
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 2 8  
VLAN Mapping
This chapter shows you how to configure VLAN mapping on the Switch.
28.1  VLAN Mapping Overview 
With VLAN mapping enabled, the Switch can map the VLAN ID and priority level of 
packets received from a private network to those used in the service provider’s 
network.
The Switch checks incoming traffic from the switch ports (non-management ports) 
against the VLAN mapping table first, the MAC learning table and then the VLAN 
table before forwarding them through the Gigabit uplink port. When VLAN 
mapping is enabled, the Switch discards the tagged packets that do not match an 
entry in the VLAN mapping table. If the incoming packets are untagged, the 
Switch adds a PVID based on the VLAN setting. 
Note: You can not enable VLAN mapping and VLAN stacking at the same time.
28.1.1  VLAN Mapping Example
In the following example figure, packets that carry VLAN ID 12 and are received 
on port 3 match a pre-configured VLAN mapping rule. The Switch translates the 
VLAN ID from 12 into 123 before forwarding the packets. Any packets carrying a 
VLAN tag other than 12 (such as 10) and received on port 3 will be dropped.
Figure 134   VLAN mapping example 
Port 3
12
10
123
10
Service Provider 
     Network