Mitel MiVOICE BUSINESS, Инструкция по инженерии

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Network Configuration Concepts
207
If there are physically separate networks for voice and data traffic, you may still need to link
these networks together and to manage the 3300 ICP from within the data portion of the network.
In this case, a router is required.
Core network
The core network potentially carries data on dedicated links at 1 Gbps or higher. The switches
at this level probably include some Layer 2 and Layer 3 switching and unite a number of subnets,
or a small number of units. These units almost certainly have UPS backup and are
cross-connected in redundant configurations, so that the failure of one device is unlikely to
result in total network failure.
Distribution layer
The distribution layer connects the core network and the users on the access layer. A distribution
layer is used within a local area, for example, within a single building or in a campus environment.
This allows local switching to stay off the core network and provides a level of continued
operation if problems occur in the core. Typically, network devices such as servers and printers
are connected to the distribution layer. This is where the 3300 ICP connects in such a large
system. Devices in this layer usually use UPS backup.
Access layer
The access layer connects to the distribution layer by single or multiple connections. It provides
the slower 10/100 BaseT type of connections to the user. These can be cross-connected within
geographic locations. If a device fails here, then only the locally connected devices will fail.
These units may or may not have UPS backup. Consider UPS backup when voice devices are
connected to the access devices.
Figure 28: LAN Architecture
In smaller networks, the definitions of the boundaries may become a little blurred. However, even
in these smaller networks, plan a tree-type structure between the 3300 ICP and the phones.
Daisy-chaining a number of switches is not recommended since all switches become involved in
connections from one end of the chain to the other. Layering will reduce unnecessary traffic.
For more specific information on network configurations, see the 3300 ICP Technician’s
Handbook .