2. INTRODUCTION
Anetwork interface card, more commonly referred to
as a NIC, is a device that allows computers to be joined
together in a LAN, or local area network .
The network interface card acts as the liaison for the
machine to both send and receive data on the LAN .
In computer networking, a NIC provides the hardware
interface between a computer and a network.
3. Network cards are
typically available in
10/100/1000 Mbit/s
varieties. This means
they can support a
notional maximum
transfer rate of 10, 100
or 1000 Megabits per
second.
Network interface card
5. Need Of NICs
Most computer networks transfer data across a medium
at a fixed rate, often faster than the speed at which
computers can process individual bits.
To accommodate the mismatch in speed, each
computer attached to a network contain special
purpose hardware known as a network interface card
(NIC).
The NIC functions like an I/O device: it is built for a
specific network technology.
It handles the details of frame transmission or reception
without requiring the CPU to process each bit.
6. ETHERNET AND WIFI NICs
Some NIC cards work with wired connections
while others are wireless.
Most NICs support either wired Ethernet or
WiFi wireless standards.
Ethernet NICs plug into the system bus of the
PC and include jacks for network cables.
while WiFi NICs contain built-in transmitters /
receivers (transceivers).
7. Installation of NICs
The most common language or protocol for
LANs is Ethernet, sometimes referred to as
IEEE 802.3.
Alesser-used protocol is Token Ring.
When building a LAN, a network interface card
must be installed in each computer on the
network and all NICs in the network must be of
the same architecture.
For example, all must either be Ethernet cards,
Token Ring cards, or an alternate technology.
8. Cont..
An Ethernet network interface card is installed
in an available slot inside the computer.
Most newer computers have a network interface
built into the motherboard.
A separate network card is not required unless
multiple interfaces are needed or some other
type of network is used.
Newer motherboards may even have dual
network (Ethernet) interfaces built-in.
9. WORKING
Acomputer or device on a network can be
reached by its MAC (media access control)
address through the NIC card.
Every Ethernet network card has a unique 48-
bit serial number called a MAC address, which is
stored in ROM carried on the card.
The MACs on the network are used to direct
traffic between the computers.
10. Cont..
An example of a MAC address:
A1B2C3D4E5F6
The first 6 hex digits in the MAC address is the
OUI (organizationally unique identifier),
assigned by the IEEE to each manufacturer (e.g.
Cisco, Intel etc).
The rest of the MAC address can be assigned in
any wayby the manufacturer to the individual
networking devices that it manufactures
11. The back plate of the network
interface card features a port that
looks similar to a phone jack, but is
slightly larger.
Anetwork card typically has a
twisted pair, BNC, or AUI socket
where the network cable is
connected, and a few LEDs to
inform the user of whether the
network is active, and whether or
not there is data being transmitted
on it.
Port In NICs
12. UTP (Unshielded Twisted Pair) e.g. CAT6 (‘Category 6’)
That port accommodates an Ethernet cable, which
resembles a thicker version of a standard telephone
line.
14. Wireless Ethernet cards
Wireless Ethernet cards are installed like their wired
counterparts, but rather than a port for an Ethernet
cable, the card features a small antenna.
The card communicates with the central wireless switch
or hub via radio waves.
Wireless LANs may have some restrictions depending
on the material the building is made from.
For example, lead in walls can block signals between
the network interface card and hub or switch.
15. NICs on network
The card implements the electronic circuitry
required to communicate using a specific
physical layer and data link layer standard such
as Ethernet or token ring.
This provides a base for a full network protocol
stack, allowing communication among small
groups of computers on the same LAN and
large-scale network communications through
routable protocols, such as IP.
