Figure 346 VLAN Stacking Example
60.2 VLAN Stacking Port Roles
Each port can have three VLAN stacking "roles", Normal, Access, and Tunnel (the latter is for Gigabit
ports only).
• Select Normal for "regular" (non-VLAN stacking) IEEE 802.1Q frame switching.
• Select Access 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.
• 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 the Service Provider's (SP) VLAN ID (VID)).
Note: Static VLAN Tx Tagging MUST be enabled on a port where you choose Tunnel.
60.3 VLAN Tag Format
A VLAN tag (service provider VLAN stacking or customer IEEE 802.1Q) consists of the following three
fields.
Table 222 VLAN Tag Format
Type
Chapter 60 VLAN Stacking
Priority
VID
XS3800-28 User's Guide
450