Networking hardware includes all computers, peripherals,
interface cards and other equipment needed to perform data-processing and
communications within the network. 
A file server stands at the heart of most networks, very
fast computer, large amount of RAM and storage space, a fast network interface
card, network operating system software resides on this computer, along with
any software applications and data files that need to be shared.
User computers that are connected
to a network are called workstations.
Configured with a network interface card, networking software, and the
appropriate cables, does not necessarily storage capability, files can be saved
on the file server. Almost any computer can serve as a network workstation.
NETWORK HARDWARE provides the physical connection between
the network and the computer workstation.
Major factor in determining the speed and performance of a network is
most NICs are internal, with the card fitting into an expansion slot inside the
computer. Some computers, such as Mac Classics, use external boxes which are
attached to a serial port or a SCSI port. Laptop computers - built-in NIC or
network cards that slip into a PCMCIA slot.
Token Ring Cards
• Token Ring network cards look similar to
Ethernet cards
• One visible difference is the type of connector on the
back end of the card. Generally have a nine pin DIN type connector to attach
the card to the network cable.
Protocol (communications protocol) standards that
specifically address how the devices on a network communicate, for example,
– How the data is packaged for transmission
– How receiving devices acknowledge signals from sending
devices,
-How errors are detected and handled.
Logical topologies are bound to network protocols and
describe how data is moved across the network.
LAN TECHNOLOGY
Protocol
• TCP/IP and WAP for internet
• Wi-Fi for wireless networks
• Bluetooth, for short range wireless network
• Ethernet, Local Talk, Token ring for wired networks
developed by IBM in the mid-1980s.
• access method involves token-passing.
• the computers are connected so that the signal travels around
the network from one computer to another in a
LAN TECHNOLOGY
Protocol : Token Ring, logical ring. A single electronic
token moves around the ring from one computer to the next. If a computer does
not have information to transmit, it simply passes the token on to the next
workstation. If a computer wishes to transmit and receives an empty token, it
attaches data to the token. The token then proceeds around the ring until it
comes to the computer for which the data is meant- the data is captured by the
receiving computer.
Cabling
Cable is the medium through
which information usually moves
from one network device to
another .
LAN TECHNOLOGY
CABLING
• In some cases, a network will utilize only one type of
cable, other networks will use a variety of cable types
• Several types of cable are commonly used with LANs.
The standard connector for unshielded twisted pair cabling
is an RJ-45 connector. A disadvantage of UTP is that it may be susceptible to
radio and electrical frequency interference.
STP is a type of cable consists of two individual wires
wrapped in a foil shielding to help provide a more reliable data communication.
LAN TECHNOLOGY CABLING:
Shielded Twisted Pair (STP) Cable
• suitable for environments with electrical interference;
• however, the extra shielding can make the cables quite
bulky.
• often used on networks using Token
Ring topology.
NETWORK OPERATING SYSTEM (NOS)
Software that controls a network and its message (e.g.
packet) traffic and queues, controls access by multiple users to network
resources such as files, and provides for certain administrative functions,
including security. coordinate the activities of multiple computers, across a
network, acts as a director to keep the
network running, smoothly. 10
• The two major types of network
operating systems are: :
Peer to Peer
Peer to Peerresources
– Peer-to-– Client/Server
• In a peer-to-peer network, all computers are
considered equal; they all have the same abilities
to use the resources available on the network
• allow users to share resources and files located
on their computers and to access shared
found on other computers.
• do not have a file server or a centralized management
source
• designed primarily for small to medium local area
networks.
• AppleShare and Windows for Workgroups are examples of
programs that can function as peer to peer network operating systems.
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