4. Network:
A computer network is a system for
communication between computers.
Components of Networks:
People.
Hard ware.
Software.
connectivity.
Procedure.
6. Local Area Network:
A local area network is data communication
system in a limited geographical area. Like a
home, office, or small group of buildings
8. Wide Area Network:
A wide area network provides long distance
transmission of data over a large geographical areas
Comprising a country,a continent or the whole world.
The most well-known example of a WAN is the Internet.
9. Network Topology:
. The logical layout of the cables and
devices that connects the nodes of a
computer.
10. Types of Topologies:
Star Topology.
Bus Topology.
Ring Topology.
Mesh topology.
Tree Topology.
Hybrid Topology.
12. Star Topology:
All devices are connected to a central
hub.Nodes communicate across the
network by passing data through the
hub.
13. Ring Topology:
All devices are connected to one another in
the shape of a closed loop, so that each
device is connected directly to two other
devices, one on either side of it.
14. Mesh Topology:
In a true mesh topology every node has a
connection to every other node in the network
16. Hybrid Topology:
A hybrid topology is always produced when
two different basic network topologies are
connected. Two common examples for Hybrid
network are: star ring network and star bus
network.
17. Linking devices:
A type of linking mechanism needed to
interconnect at least two computers.They are used
to create a network. For example Cables,Switches
or Hubs.
19. Repeaters :
A network device used to regenerate or replicate
a signal. Repeaters are used in transmission
systems to regenerate analog or digital signals
distorted by transmission loss.
20. Bridges :
A Bridge is an interface used to connect the
same types of networks.
28. BROUTER:
A Brouter is a single protocol or multi protocol
router that sometimes acts as a router and sometimes
as a bridge.
29. Switches :
Switches are the hardware or software devices
capable of creating temporary links between two or
more devices linking to the switch but not to each.
30. Hubs:
A Hub is the simple connection point for different
type of devices on a network. It sends all the data to
all devices connected to it.
31. Nodes:
Any device that is attached to a network.A node
may be a microcomputer,terminal,storage
device or peripheral device which enhance the
usefulness of the network.
41. Frequency spectrum and bandwidth:
The frequency spectrum of a signals is
the collection of all the component
frequencies that it contain .
The bandwidth of a signal is the width of
frequency spectrum.
43. Bit interval and bit rate:
The bit interval is the time required
to send a single bit.
The bit rate is number of bit intervals per
second,usually expressed in bits per second.
