SMC Networks 8606SX - annexe 1, Руководство по управлению

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Virtual LANs
Switches do not inherently support broadcast domains, which can
lead to broadcast storms in large networks that handle a lot of IPX
traffic. In conventional networks with routers, broadcast traffic is
split up into separate domains to confine broadcast traffic to the
originating group and provide a much cleaner network
environment. By supporting VLANs, this switch allows you to
create segregated broadcast domains. However, note that if you
need to support intra-VLAN communications, you must use a
router or Layer 3 switch (such as the SMC6716L3).
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, but also 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 Layer 3 switch or a router to reach a different VLAN.
This switch supports the following VLAN features:
• Up to 16 VLANs based on the IEEE 802.1Q standard
• Distributed VLAN learning across multiple switches using
explicit or implicit tagging
• Port overlapping, allowing a port to participate in multiple
VLANs