Routers are devices that implement the
network service. They provide interfaces for a wide range of links and
subnetworks at a wide range of speeds. Routers are active and intelligent network devices and thus can participate in managing the network.
Routers manage networks by providing dynamic control over
resources and supporting the tasks and goals for networks. These goals
are
connectivity, reliable performance, management control, and
flexibility.
A WAN switch is a multiport networking
device, which typically switches such traffic as Frame Relay, X.25,
and Switched Multimegabit Data Service (SMDS). WAN switches typically operate at
the data link layer of the OSI reference model. The Figure illustrates two routers at remote ends of
a WAN that are connected by WAN switches. In this example, the
switches filter, forward, and flood frames based on the destination
address of each frame.
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Case
Study |
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Washington
Project: Deployment
of Switches
As part of the
Washington School District network design and
implementation, you need to determine what type of
switches to obtain, how many of them to obtain,
and where to place them in the network. Possible
locations include the MDFs and IDFs in the school
locations and at the main district office.
Additionally, you need to determine what types of
switches are needed, such as LAN or WAN switches,
and whether they need to be Layer 2 or Layer 3
switches. Finally, you need to determine the
segmentation and security required to establish
the types, number, and placement of switches in
the network. |
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