DragonWave AirPair 100-UL, Руководство по эксплуатации продукта

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4.6. VLAN tagging
A Local Area Network (LAN) is a single-broadcast domain. If a user broadcasts information on
the LAN, every other user on the LAN receives the broadcast. A router prevents broadcast
messages from leaving a LAN, which reduces collisions and improves performance.
A network manager can create smaller broadcast domains and reduce network broadcasts by
logically segmenting a LAN into different broadcast domains. These broadcast domains are
called Virtual Local Area Networks (VLANs). Workstations on a VLAN do not have to be located
together because they are segmented logically, not physically.
VLANs offer a number of advantages over traditional LANs including:
•
Performance
•
Security
•
formation of virtual workgroups
•
cost reduction
All ports on a switch are configured for a default VLAN (usually VLAN1). When a switch receives
data from a workstation, it tags the data with a VLAN identifier indicating the originating VLAN.
The switch sends the data to the ports inside the VLAN where it originated. It also sends the
data to a trunking port if one is available.
Network Administrators create VLAN groups and place backbone network devices into the VLAN
group to simplify administration and increase security of the devices. VLAN tagging allows
network administrators to add AirPair nodes to the administrative network. VLAN tagging
restricts administrative access to devices that are members of the VLAN group.
If you program an AirPair node with an IP address but do not enable VLAN tagging, the node
responds to Ping, Telnet and SNMP commands from any device on the network. Telnet and
SNMP require a username and password, the proper IP address and community string,
respectively.
If you enable VLAN tagging, the AirPair nodes respond to ping commands but do not respond to
Telnet and SNMP commands unless the packet has the correct VLAN tag. The Telnet and
SNMP requests must have the correct VLAN tag and come from a device within the VLAN
domain.
The Institute of Electrical and Electronic Engineers (IEEE) is working on a draft standard 802.1Q
for VLANs. Currently, most products are proprietary and anyone wanting to install VLANs has to
purchase all products from the same vendor. DragonWave implements AirPair VLAN Tagging
using the 802.1Q standard. For more information on the Standard, see the web page:
http://grouper.ieee.org/groups/802/1/pages/802.1Q.html
AirPair 100 UL 24 GHz Product Manual