Vlan Stacking Port Roles; Vlan Tag Format; Figure 58 Vlan Stacking Example; Table 42 Vlan Tag Format - ZyXEL Communications GS-4024 User Manual

GS-4024 User's Guide

Figure 58 VLAN Stacking Example

21.2 VLAN Stacking Port Roles

Each port can have three VLAN stacking "roles", Normal, Access Port and Tunnel (the latter
is for Gigabit ports only).
• 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 (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.

21.3 VLAN Tag Format

A VLAN tag (service provider VLAN stacking or customer IEEE 802.1Q) consists of the
following three fields.

Table 42 VLAN Tag Format

Type
138
Priority VID
Chapter 21 VLAN Stacking