Allied Telesis AT-S39 - Manual (Page 120)

Section II: Local and Telnet Management
120
As a software-based solution, VLANs eliminate the restrictions of existing
network design and cabling infrastructure and allow the centralized
configuration of switches located in physically diverse locations. VLAN
memberships are changed quickly and efficiently from the management
console rather than the wiring closet.
Increased
Security
VLANs provide additional security not available in a shared media
network environment. Because a switched network only delivers frames
to intended recipients, and only broadcasts frames to other members of
the VLAN, a network administrator can segment users requiring access
to sensitive information into separate VLANs from the rest of the general
user community.
Since data traffic generated by a node in a VLAN is restricted only to the
other nodes of the same VLAN, VLANs can be used to control the flow of
data in your network and prevent data from flowing to unauthorized
end nodes.
VLAN Modes The AT-8000 Series switch supports the following VLAN modes:
❑ User-configured VLANs
— Port-based
— Tagged
❑ Multiple VLANs
— 802.1Q compliant
— non-802.1Q compliant
These VLANs are described in the following sections.
Note
User-configured VLANs are 802.1Q compliant. The only non-802.1Q
compliant VLAN mode is non-802.1Q compliant multiple VLAN
mode. This mode would generally be used in a network supporting
non-802.1Q compliant devices.