ZyXEL Communications OLT2406, User Manual

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Chapter 75 VLAN Stacking and Translation
OLT2406 User’s Guide
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Note: Static VLAN Tx tagging MUST be enabled on a port where you choose tunnel port.
75.2 VLAN Translation Overview
With VLAN translation enabled, the OLT 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 OLT checks incoming traffic from the switch ports (Non-management ports) against the VLAN
translation table first, the MAC learning table and then the VLAN table before forwarding them through
an uplink port. When VLAN translation miss drop is enabled, the OLT discards the tagged packets that
do not match an entry in the VLAN translation table.
75.2.1 VLAN Translation Example
In the following example figure, packets that carry VLAN ID 12 and are received on port 3 match a pre-
configured VLAN translation rule. The OLT translates the VLAN ID from 12 into 123 before forwarding the
packets.
Figure 266 VLAN Translation Example
75.3 VLAN Tag Format
A VLAN tag (Service provider VLAN stacking or customer IEEE 802.1Q) consists of the following three
fields.
“Type” is a standard Ethernet type code identifying the frame and indicates that whether the frame
carries IEEE 802.1Q tag information. SP TPID (Service Provider Tag Protocol Identifier) is the service
provider VLAN stacking tag type. Many vendors use 0x8100 or 0x9100.
TPID (Tag Protocol Identifier) is the customer IEEE 802.1Q tag.
Port 3
12
10
123
10
Service Provider
Network
Table 268 VLAN Tag Format
Type Priority VID