Configuration Guide Vol. 2


18.1.3 802.1Q Tag assignment function

802.1Q Tag addition function is used to VLAN Tag mirroring frames. This feature allows mirroring frames to be forwarded to Layer 2 forwarding based on VLAN Tag they are attached to, and to traffic monitoring devices such as analyzers at remote locations. However, because MAC address of the mirroring frame uses MAC address of the frame received on the monitor port as is, the device that relays the mirroring frame receives a frame with a MAC address that differs from the actual network configuration. Therefore, VLAN used for forwarding (VLAN Tag attached to the mirroring frame) should suppress MAC addresslearning.

When configured as a mirror port, but you want to use this feature, you can use features other than protocol VLAN and MAC VLAN.

The following tables describe VLAN Tag fields that 802.1Q Tag feature assigns to frames.

Table 18-1 VLAN Tag field attached to frame by 802.1Q Tag adding function

field

Description

Support

TPID

EtherType indicating that IEEE802.1Q VLAN Tag will continue

The value set in the configuration is applied. Only one device type can be specified.

User Priority

IEEE802.1D priority

This function supports only the default (3).

CF

(Canonical Format)

Whether MAC addressin MAC headers conforms to the standard-format

This function supports only the standard (0).

VLAN ID

VLAN ID

VLAN ID that can be used by the user is 2 to 4094. Only one device type can be specified.