IP-COM G3210P, Руководство пользователя

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Advanced Settings
VLAN Management
In traditional medium sharing Ethernet and switched Ethernet, all users are in a broadcast
domain. With more and more PCs appearing in the networking, broadcast packets
increase, which greatly increases data flow among devices in the networking. Thus,
network performance becomes worse. With networking expands, broadcast storm may
occur and the entire network may be paralyzed.
A Virtual Local Area Network (VLAN) is a network topology which allows to logically
instead of physically segment a LAN into several net segments. A VLAN combines a
group of hosts with a common set of requirements logically instead of physically relocating
devices or connections.
VLANs allow a network to be logically segmented into different broadcast domains. All
members in a VLAN are treated as in the same broadcast domain and communicate as if
they were on the same net segment, regardless of their physical locations. Logically, a
VLAN can be equated to a broadcast domain, because broadcast packets are forwarded
to only members of the VLAN on which the broadcast was initiated. Different VLANs
cannot intercommunicate directly. Inter-VLAN communication can only be achieved using
a router or other layer 3 devices that are able to perform Layer 3 forwarding. VLAN
network topology can be shown as below:
Compared with the traditional Ethernet, VLAN enjoys the following advantages:
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Better network performance. By restricting all broadcast traffic to a VLAN, it saves
network bandwidth and enhances network performance.
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Reduced cost. The use of VLANs to create broadcast domains eliminates the need
for traditional routers to handle this function, permitting operation at lower latencies
and cost compared to routers under heavy load and at high cost.
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Ease of network management. Members of a VLAN group can be geographically