D-Link DES-3326SR, User Manual

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DES-3326SR Layer 3 Fast Ethernet Switch User’s Guide
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5.
Develop a security scheme. Some subnets on the
network need more security or should be isolated from
the other subnets. IP or MAC filtering can be used.
Also, one or more VLANs on the Layer 3 switch can be
configured without an IP subnet – in which case, these
VLANs will function as a layer 2 VLAN and would
require an external router to connect to the rest of the
network.
6.
Develop a policy scheme. Some subnets will have a
greater need for multicasting bandwidth, for example. A
policy is a mechanism to alter the normal packet
forwarding in a network device, and can be used to
intelligently allocate bandwidth to time-critical
applications such as the integration of voice, video, and
data on the network.
7.
Develop a redundancy scheme. Planning redundant
links and routes to network critical resources can save
valuable time in case of a link or device failure. The
DES-3326SR Spanning Tree function can be used to
block the redundant link until it is needed.
VLAN Layout
VLANs on the DES-3326SR have rather more functions than on
a traditional layer 2 switch, and must therefore be laid-out and
configured with a bit more care. VLANs with an IP interface
assigned to them could be thought of as network links – not
just as a collection of associated end users. Further, VLANs
assigned an IP network address and subnet mask enables IP
routing between them.
VLANs must be configured on the switch before they can be
assigned IP subnets. Further, the static VLAN configuration is
specified on a per port basis. On the DES-3326SR, a VLAN can
consist of end-nodes – just like a traditional layer 2 switch, but
a VLAN can also consist of one or more layer 2 switches – each