31-12-2010, 01:43 PM
[attachment=7798]
SUBMITTED BY:
MAYUR KALRA
Computer Networks
What is A Network
A Network is a group of two or more computer systems linked together.
Two computers are said to be interconnected if they are able to exchange information
The connection need not be via a copper wire fiber optics microwaves, infrared and communication satellites can also be used
TYPES OF NETWORKS
Local-Area Networks (LAN's):
Metropolitan-Area Networks (MAN's):
Wide-Area Networks (WAN's):
Network connecting two or more geographically distinct LANs
The Internet is an intricate and extensive WAN spanning the globe
NETWORK TOPOLOGIES
A topology is a way of “laying out the network”
ADVANTAGES
Works well for small networks
Inexpensive to implement on a small scale
Requires less cable
Easy to add another workstation
DISADVANTAGES
Management costs often too high
Possible for defective node to take down the entire network
Subject to congestion from network traffic
ADVANTAGES
Easier to manage than a bus
Easier to locate node and cable problems
Easier to expand than a bus or ring, especially for enterprise networking
Well suited for expansion into high-speed networking
DISADVANTAGES
Susceptible to a single point of failure
Requires more network cable at the start than a bus
Ring Topology (LAN)
Every device interconnected
Most expensive
Most Fault tolerant
Cable fault tolerant
Device fault tolerant
The Internet is Mesh Topology