ZyXEL Communications MES-2110, User Manual

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Chapter 11 VLAN
MES-2110 User’s Guide
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distinguish customer A and tag 48 to distinguish customer B at edge device 1 and
then stripping those tags at edge device 2 as the data frames leave the network.
Figure 40 VLAN Stacking Example
11.5.3 VLAN Stacking Port Roles
Each port can have three VLAN stacking “roles”, Normal , Access Port and
Tunnel (the latter is for Gigabit ports only).
Note: Some devices do not support all roles.
• Select Normal for “regular” (non-VLAN stacking) IEEE 802.1Q frame switching.
• Select Access Port for ingress ports on the service provider's edge devices ( 1
and 2 in the VLAN stacking example figure). The incoming frame is treated as
"untagged", so a second VLAN tag (outer VLAN tag) can be added.
Note: Static VLAN Tx Tagging MUST be disabled on a port where you choose
Normal or Access Port .
• Select Tunnel Port (available for Gigabit ports only) for egress ports at the
edge of the service provider's network. All VLANs belonging to a customer can
be aggregated into a single service provider's VLAN (using the outer VLAN tag
defined by SP VID).
Note: Static VLAN Tx Tagging MUST be enabled on a port where you choose
Tunnel Port .