ZyXEL Communications XGS2220 Series, Руководство пользователя

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Chapter 59 VLAN Stacking
XGS2220 Series User’s Guide
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Figure 296 VLAN Stacking Example
59.2 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 .
59.3 VLAN Tag Format
A VLAN tag (service provider VLAN stacking or customer IEEE 802.1Q) consists of the following three
fields.
Table 219 VLAN Tag Format
Type Priority VID