Allied Telesis FORMULA 8200 - Manual (Page 37)

FORMULA 8200 User’s Guide
3-5
Virtual Bridges,
Virtual
Interfaces,
Virtual Routers
Each VLAN has a virtual bridge that maintains the locations of the
end stations on each segment and controls the switching hardware.
Each of the interfaces on a virtual bridge is called a
virtual interface .
Each VLAN is identified by a number. These numbers are global to all
FORMULA 8200 switches that are connected by a backbone network.
Traffic can be exchanged over a backbone network in order to allow
a VLAN to have segments that are distributed among multiple
FORMULA 8200 switches. Traffic can be exchanged between VLANs
by either internal or external routing.
Use the VLAN/SHOW/VLAN command to see the virtual VLAN
information. Refer to Chapter 5 for details on the command.
An optional virtual router interface can be configured to forward
traffic between VLANs by using the
VLAN/CONFIG command; see
Configuring a Virtual LAN (VLAN) later in this chapter.
Use the VLAN/SHOW/VROUTER command to see the virtual router
information. Refer to Chapter 5 for details on the command.
To access the FORMULA 8200 management applications remotely
via TCP/IP, the IP interface must be enabled on at least one VLAN
(usually VLAN 1). The management applications may then be
accessed from a station that has access to one of the LAN segments
comprising that VLAN. If the interface over which management
functions are taking place is disabled, it is possible to lose contact
with the FORMULA 8200. In this case, you must use the console port
to reestablish remote TCP/IP management capabilities.
Each VLAN has an associated virtual bridge. A distributed VLAN has
one virtual bridge on each FORMULA 8200 that has interfaces
participating in the VLAN. The virtual bridge implements the IEEE
802.1-D Spanning Tree Algorithm and Protocol, described in the next
section.
Use the VLAN/SHOW/VPORT command to view the virtual port
information, and VLAN/SHOW/VSTATS command to view the
virtual port statistics.