Main Network Hardware Components
Ø Hub–
electronic device (with a number of ports) used in a LAN to link groups of
computers.
Ø Repeaters (also
called amplifiers) – electronic devices that receive signals and amplify and
send them along the network.
Ø Routers -
electronic devices used to ensure messages are sent to their intended
destinations.
Ø Gateway–
consists of hardware and/or software that allows communications between
dissimilar networks.
Ø Bridge–
consists of hardware and/or software that allows communication between two
similar networks.
Why used Interconnect?
Ø To
connect two LANs with different protocols.
Ø To
connect a LAN to the Internet.
Ø To
break a LAN into segments to relieve traffic congestion.
Ø To
provide a security wall between two different types of users.
Ø To
connect WLAN to LAN
Ø Remote
Access.
Interconnection
within similar networks or dissimilar networks done via different devices
ü Computers within a LAN are often connected using
a hub.
ü LAN to LAN connections are often performed with
a bridge.
ü Segments of a LAN are usually connected
using a switch.
ü LAN to WAN connections are usually performed
with a router.
Networks
are usually classified using three properties:
Ø Topology
Ø Protocol
Ø Architecture
Ø Topology
Refers
to the way computers and peripherals are configured to form networks. There are
several topologies use in networking.
Star Topology
The
star topology is a popular method of connecting the cabling in a computer
network. In a star, each device connects to a central point via a point-to point
link.
Ring Topology
The Ring Topology
is a physical, closed loop consisting of point-to-point links. It
receives a transmission from the previous node and amplifies it before passing
it on.
Bus Topology
In
a Bus topology, all devices attach to the same transmission medium. The medium
has a physical beginning and end. All buses are implemented using electrical
cable, usually coax, and the ends of the cable must be terminated with a
terminating resistor that matches the impedance of the cable. The bus is considered
a multipoint system because all devices tap into the same backbone cable.
Hybrid Topology
The
Hybrid topology scheme combines multiple topologies into one large topology.
The hybrid network is common in large wide area networks.
Ø Protocol
A
protocol is simply an agreed-on set of rules and procedures for transmitting
data between two or more devices.
Ø Architecture
Network
architecture refers to the way a network is designed and built. There are two
major types.
Peer-to-peer
architecture– Computers connect with each other in a work-group to
share files, printers, and Internet access. This is used to connect a small number
of computers.
Client/server architecture– sends information
from a client computer to a server, which then relays the information back to
the client computer, or to other computers on the network.
