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 Understand
why various networking
topologies are used
 Variations of standard networking
topologies
 Deciding from the products required to
determine the best network topology the
environment.
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 Good
network design includes:
• Analyzing network requirement
• Selecting a network topology
• Selecting equipment to fit that topology
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


Topology refers to physical layout including computers,
cables, and other resources
Determines how components communicate
Basic network design is referred to as topology, layout,
diagram, and map
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 Three
common topologies:
• Bus- A single cable connection, all nodes are
connected to one central node that routes all
data passing to and from them.
• Star- Computers are connected through a
central point, called a hub.
• Ring- Data are passed round the ring in one
direction only, like a loop.
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 The
bus topology is the easiest to
manager.
 Data on a star network always passes
through the hub, switch, or concentrator
before continuing to its destination.
 Components connect via backbone or
single cable segment
 If the cable break data can not be
processed, the network fails.
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

In bus topology, only one computer can send
information at a time
Bus is a passive topology
• The computers on the network simply listen and receive the
signal, they don’t amplify the signal in any way.

In active topology, computers are responsible for
sending the data along the network.
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A
non-terminated signal that continues to
navigate the network, travels across the
medium, a signal transmits to both ends
of any bus.
 During a bus communication cable
termination, a terminator is attached that
prevents a signal from bouncing.
 A failure of communication can occur
when the cable is cut or disconnected.
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


In today’s networks the star topology has become the
dominant topology.
Another major topology which the computers connect
via a central connecting point
Requires more cable and has single point of failure
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http://chauncy-ict.pbworks.com/f/network_star.jpg
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 Data
that is passed round the ring in one
direction only, like a loop.
• May be physically wired as a star with central
hub passing token in a circle
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http://bucarotechelp.com/networking/images/ring.gif
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 Wired-like
star networked topology
device, which handles traffic like a ring
 Fiber Distributed Data Interface
(FDDI)
• When one ring fails, dual ring network uses
secondary ring and continues to work
 Shares
network resources equally
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 Eliminate
cables
 Wireless LANs use centralized device
similar to hub to control communication
• Use star topology
• Signals travel through one central device
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 May
be active or
passive
• Downside of an active
hub it require a cable
bandwidth shared
among connected
stations.
• Passive hub no
electrical power is
required. A simply
central connection point,
with no amplification or
regeneration.
http://www.jarviser.co.uk/jarviser/images2/twohubs.jpg
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 Networks
build upon one of three
basic topologies
 Hub, a central point of concentration
for star network, passes electronic
signals to network
 Network layout should be consistent
with existing network and accurately
maintained as network changes
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