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Switches do not inherently support broadcast domains, which can lead to broadcast storms in large
networks that handle a lot of traffic such as NetBUEI or IPX. In conventional networks with routers,
broadcast traffic is split up into separate domains to confine this traffic to the originating group and
provide a much cleaner network environment. Instead of using physically separate subnets which are
linked by traditionally slow routers, this switch creates segregated broadcast domains based on easily
configurable VLANs, and then links these VLANs as required with wire-speed routing.
An IEEE 802.1Q VLAN is a group of ports that can be located anywhere in the network, but
communicate as though they belong to the same physical segment. VLANs help to simplify network
management by allowing you to move devices to a new VLAN without having to change any physical
connections. VLANs can be easily organized to reflect departmental groups (such as Marketing or
R&D), usage groups (such as e-mail), or multicast groups (used for multimedia applications such as
video conferencing).
VLANs provide greater network efficiency by reducing broadcast traffic, and allow you to make network
changes without having to update IP addresses or IP subnets. VLANs inherently provide a high level of
network security since traffic must pass through a configured Layer 3 link to reach a different VLAN.
This switch supports the following VLAN features:
Up to 128 VLANs based on the IEEE 802.1Q standard
Distributed VLAN learning across multiple switches using explicit or implicit tagging and GVRP
protocol
Port overlapping, allowing a port to participate in multiple VLANs.
End stations can belong to multiple VLANs
Passing traffic between VLAN-aware and VLAN-unaware devices