data communication and networking

complete note of data communication and networking

1. Unit-2
COMMUNICATION AND NETWORKING

2. Data Communication System:
▪Communicationreferstotheexchangeofinformation
betweensenderandreceiverwiththehelpof
electronicmeansofcommunication.
▪Theelectronicmeansofcommunicationmaybe
wires,radioorsatellite.
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3. Data communication and networking 3

4. Block Diagram of Communication System/Model
•The communication system consists of information transmission from
one point to another. The original information signal is passes
through various stages and many changes in its orientation and shape
because of noise and attenuation (decreasing).
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5. •The sourcegenerates the information which comes from any
source.
•Then source encoder translates source information into
electrical form.
•A transmitter (TX) transfers encoded form of information into
channel.
•Channelis the physical medium that connects the transmitter
to the receiver. The channels are transmission medias that
transform data into receiver.
•The receiver (RX) receives the incoming information and
transfers into a source decoder.
•Finally, source decoder converts the electrical signal back to a
form acceptable to the receiver and provide to the users.
•Sink: A sink is the user of the information generated by the
source. It is a final block in the communication system which
receives the message signal.
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6. Computer Network
•Computernetworkingreferstointerconnectedcomputing
devicesthatcanexchangedataandshareresourceswitheach
otherwiththehelpoftransmissionmediaandsetofrules.
•Example:humannetworks,telephonenetworks,radio
networks,computernetworks,etc.
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7. Advantages of computer network :
1.Easeofaccessibility:
Moderncomputernetworksareeasytoexplore.So,evenifyouareakidora
personnewtotechnology,you'llfinditeasytoconnect.
2.Flexibility:
Flexibilitymeansthatdifferentpeoplewillbeabletoexploredifferentthingsasper
theirrequirements.Eg:e-mailormessagingappslikeWhatsApp.
3.Convenientresourcesharing:
Youcanuseresourcessuchasprinters,scannersandphotocopymachinesthatcan
besharedacrossmultipleusers.
4.Connectivity:
ComputerNetworksimproveconnectivityirrespectiveofaperson'slocation.Eg-
asweusevideocallappsorGoogledocumentstoconnectwithourfriendsand
colleagues.
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8. Disadvantages of computer network :
1. Cost of thenetwork –
The expense of executing the system including cabling and equipment can
be expensive.
2. Security Problem: Network security is the most challenging job for
network administrator in order to protect network resources from
unauthorized users and physical destructions.
3. Needs Technical Person: It is very difficult to install and operate good
computer network. In order to manage computer network, the
organization needs network specialist. So it is very expensive for an
organization to hire network specialist.
4. Depends on centralized device: Computer networking depends on
centralized devices like server, hub, router, etc. So, if there is problem on
central devices, then whole network can be stopped.
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9. Direction of communication flow
•Direction of communication refers to how data is transmitted
between senderand receiver.
•It is also know as mode of transmission.
•Classified into three types:
I.Simplex
II.Half duplex
III.Full duplex
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10. Simplex
•The flow of data signal in simplex mode of communication is
unidirectional.
•Only one of two devices on a link can transmit data and the other can
receive.
•EX:
➢Communication b/w keyboard and computer
➢Radio and TV broadcasting etc
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11. Half Duplex:
•Half-duplex data transmission means that data can be transmitted in
both directions (bidirectional).But, both devices cannot receive and
transmit data at the same time.
•Ex: communication between walkie-talkie
Full duplex
•Full-duplex data transmission means that data can be transmitted in
both directions. Both device can receive and transmit data at the same
time. .
•Ex :communication in telephone ,cell phone etc.
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12. Types of Network
On the basis of geographical area
1.Local area network (LAN)
2.Metropolitan area network (MAN)
3.Wide area network (WAN)
On the basis of networkarchitecture
1.Peer to peer network architecture
2.Client server network architecture
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13. Local area network (LAN):
❖LAN is small privately owned network that covers only few
kilometers such as within a room, office or buildings (up to
3KM).
❖It connects the network resources such as computers, faxes,
printers, and various networking devices.
❖Moreover, user also can share the resources such as data,
file, software, etc. in the network.
❖It has higher speed data transfer rate maximum up to
1000mbps.
❖It is highly secured and it has least errorrate than others.
❖It is less expensive type of network because it requires least
expensive devices -NIC, Hub Bridges, Modem and switches
etc.
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14. Data communication and networking 14

15. Advantages
1.Data transmission speed is faster than MAN and WAN.
2.It has higher security to resources of the network
3.It is easy to manage and operate.
Disadvantages
1.It is limited only to small area.
2.Initial setup cost is high .
3.It comparatively connects a small number of computers.
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16. Metropolitan Area Network
•MAN is complex and heterogeneous type of network and it may be either
public or private.
•The size of MAN is bigger than LAN and it covers maximum up to 100km.
•This network uses bridges, repeater, router, gateway and microwave station
etc.
•It uses different types of media such as coaxial cable, optical fiber, microwave
etc.
•It can connect 100s of LAN and 1000sof individual computers.
Example -ATM, cable TV etc.
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17. Advantages
1.Covers large geographical area.
2.It can connect dissimilar systems and networks.
3.Public libraries and government agencies typically use a
MAN.
Disadvantages:
1.Transmission speed is usually slower compared to the LAN.
2.It is complex to establish, manage and provide security.
3.It is expensive to run than LAN.
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18. Data communication and networking 18

19. Wide area network
•WAN is a network that exists over a large-scalegeographical
area.
•It has low speed data speed transfer 64Kbps to 10 Mbps or
more.
•It uses various types of transmission media such as telephone
line, optical fiber, radio wave, microwave, satellite, etc.
•It uses mesh and hybrid topologies.
•It can connect unlimited LANs and MANs.
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20. Advantages :
➢It is spread to a large area than LAN and MAN.
➢It also connects dissimilar systems and networks.
➢Allow you to share the data to all of your connected devices in
a network.
Disadvantages:
➢It is the most expensive type of network because it requires
large amount of expensive devices such as router , gateway,
microwave station ,satellite etc.
➢It is complex to establish, manage and provide security.
➢Transmission speed is usually slower compare to LAN and
MAN.
➢It is less secured network and it has highest error rate.
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21. Computer Network Architecture
Computer Network Architecture is defined as the physical and logical
design of the software, hardware, protocols, and media of the
transmission of data.
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22. Peer to peer network architecture
➢Peer-To-Peer network is a network in which all the computers
are linked together with equal privilege and responsibilities
for processing the data.
➢Peer-To-Peer network is useful for small environments,
usually up to 10 computers.
➢Peer-To-Peer network has no dedicated server.
➢Special permissions are assigned to each computer for sharing
the resources, but this can lead to a problem if the computer
with the resource is down.
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23. Data communication and networking 23

24. •It P2P network is easier to set up.
•The p2p network is lessexpensive.
•In P2P all nodes are act as serveras well as client therefore no need
of dedicated server.
•Each node has equal privileges to access the resources of its own and
others nodes connected to the network.
•It is suitable for small sized network which has maximum 10 nodes.
Advantage of peer to peer network
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25. Disadvantages of peer to peer network
•Its performance becomes very poor for large size network.
•No centralized server is available to manage and control the access of
data.
•Network security problemsdue to equal privileges of the nodes.
•Data recovery or backup is very difficult.
•Each computer should have its own back-up system
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26. Client server network architecture
•The client-server model describes how aserver provides resources and
servicesto one or moreclients.
•Examples of servers includewebservers,mailservers, andfileservers.
•Each of these servers provide resources to client devices, such
asdesktopcomputers,laptops,tablets, andsmart phones.
•Most servers have a one-to-manyrelationship with clients, meaning a
single server can provide resources to multiple clients at one time.
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27. Client server network architecture
▪Client/server architecture works when the client computer sends a
resource or process request to the server over the network
connection, which is then processed and delivered to the client.
▪A server computer can manage several clients simultaneously,
whereas one client can be connected to several servers at a time,
each providing a different set of services.
▪In its simplest form, the internetis also based on client/server
architecture where web servers serve many simultaneous users with
website data.
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28. Advantages
•It is easier for centralized administration, controlling and monitoring
the entire network from server.
•It provides centralized backup and recovery.
•It is easier for managing the large size network.
•Security :Rules defining security and access rights can be defined at
the time of set-up of server.
•Servers can play different roles for different clients.
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29. Disadvantages
•CongestioninNetwork:Toomanyrequestsfromtheclientsmay
leadtocongestion.
•Overloadcanleadtobreaking-downofservers.
•Cost:Itisveryexpensivetoinstallandmanagethistypeof
computing.
•YouneedprofessionalITpeopletomaintaintheserversandother
technicaldetailsofnetwork.
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30. Network Topologies:
•Topology refers to the physical structure of a network that
deals with how computers are interconnected by using
cabling system.
•Common LAN topologies are
➢Bus
➢Star
➢Ring
➢Tree
➢Mesh
➢Hybrid
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31. 1.BUS Topology
•Computers are connected to a single continuous cable that is called
‘bus’.
•The cable to which the nodes connect is called a "backbone".
•A bus must be terminated on both sides to prevent signal bounce.
•computers are connected to the bus with the help of drop line and T-
connector(tap).
•A bus runs throughout the office to which all the computers are
connected.
•It is based on client server network architecture.
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32. •It works well when you have a small network.
•It‘s simple and easy to setup and extend the network.
•If any computer in the network downs, then it does not affect other
computers.
•It requires less cable length and network devices than a other topology
(Inexpensive).
•It is more flexible because we can easily connect and disconnectany
number of computers in the bus.
Advantages:
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33. Disadvantages of bus topology
•Data traffic is very high in bus so there may be chance of data
collision.
•It can be difficult to identify the problemsif the whole network goes
down.
•Bus topology is not great for large networks.
•Terminatorsare required for both ends of the main cable.
•Additionaldevices slowthe network down.
•If a main cable is damaged, the network failsor splits into two.
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34. •Star topology is a network topology where each individual piece of a
network is attached to a central node (often called a hub or switch).
•Star topology is also known as a star network.
•It is based on client server architecture.
•The communication is done with the help of hub or switch in the
entire network.
•The hub controls traffic on the network.
2. Star topologies
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35. Advantages of star topologies:
•It is simple, reliable and easy to set up and re-configuration.
•It is flexible to connect new computer and remove existing
computer in the network.
•It is very easy to find out fault because of the use of hub or
switch.
•If any computer in the network goes down, then other computers
can continuetheir functions.
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36. Disadvantages of star topologies:
•It requires very large amount of cables.
•It is expensivebecause of cables and networking devices hub or
switches.
•If there is any problem in central devices hub or switchesthen the
entire network will be down.
•The data traffic is high in central device hub.
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37. 3. RING TOPOLOGY
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➢Computers are interconnected to each other by making a closed circular structure that
means each computer is connected to other two adjacent computers in either side.
➢It is based on peer to peer network architecture.
➢Communication is done in single direction only.
➢When one computer receives the message, then it compares the destination address of
the message and its own address, if it matches then it accepts the message otherwise
the message is retransmitted to the next computer in the network.

38. Advantages:
•It is simple and inexpensive.
•There is lesschance of data collision because of unidirectionaldata
transmission.
•There is no server so each computer has equal access facilities to the
resource.
Disadvantages:
•It is not flexible topology-hard to add or remove new nodes.
•It is not suitable for largesize network.
•It is very difficult to find out the errors in the network.
•Failure of one computer disturbs whole network.
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39. 4. Tree Topology :
➢Atree topology is sometimes known as a star bus topology
because it combines features of both star and bus topologies
to create a tree-like structure.
➢In this topology, every branch contains Star Network, and its
main structure is designed in the form of a bus backbone
cable.
➢It is a very flexible computer networking method that allows
you to add Network Devices to this network by simply
expanding the Star Network at each branch of a tree.
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40. Advantages of Tree Topology:
•The other nodes in a network are not affected if one of their nodes
gets damaged or does not work.
•Tree topology provides easy maintenance and easy fault
identification can be done
•Tree Topology is highly secure and reliable.
•It is used in WAN.
Advantages of Tree Topology:
•Requires a large number of cables compared to star and ring
topology.
•The Backbone appears as the failure point of the entire segment of
the network.
•The establishment cost increases as well.
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41. TRANSMISSION MEDIA
•It is a communication channel that carries the
information from the sender to the receiver.
•Data is transmitted through the electromagnetic
signals.
•The main functionality of the transmission media is
to carry the information in the form of bits
throughLAN.
•It is a physical path between transmitter and receiver
in data communication.
•In a copper-based network, the bits in the form of
electrical signals.
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43. BOUNDED MEDIA
•Bounded media are physical cables that signals travel through on a
narrow path.
•Bounded media are made up of an external conductor (usually
copper) wrapped in a jacket made of nonconductive material.
•Most common bounded media :
1. Twisted Pair Cable
2. Coaxial Cable
3. Fiber Optics Cable
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44. Twisted pair cable
•It is made from a copper wire twisted to each other and surrounded by
outer insulating jacket.
•One wire is used for receiving data and the other for transmitting data.
•It is used for both analog and digital transmission and is available in
different categories.
•It is available in two forms :
1.Unshielded Twisted Pair -telephone.
2.Shielded Twisted Pair -LAN
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46. Data communication and networking 46

47. Advantages of twisted pair cable
•It is inexpensive and suitable for data transmission.
•It is flexible and easier to operate.
•It has higher data transfer rate up to Gbps(Gigabits per
second).
Disadvantages of twisted pair cable
•It cannot transfer data for long distance.
•It emits electromagnetic interference.
•It is not suitable for analog data such as video transmission.
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48. Coaxial cable
•Itconsistsoftwoconductor–innercopperconductoris
surroundedbyaninsulatoroverwhichasleeveofcopper
meshiswoven.
•ThiscoppermeshisgainsurroundedbyPVCjacket.
•ItspanslongerdistanceathigherspeedthanUTP.
•Itisavailableintwoforms:
1.ThinnetCoaxialCable–Itisknownas10Base2which
referstoitcarrying10mpbssignalmaximumupto200m.
Itispopularinbustopology.
2.ThicknetCoaxialCable–Itisknownas100Base5which
referstoitcarrying100mbpssignalmaximumupto500m.
Itisusedincabletv.
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49. Advantages of coaxial cable
•It has higher bandwidth compared to unshielded
twisted pair cable.
•It is less effective by electromagnetic interference.
•It can support multiple channels in a medium.
Disadvantages of coaxial cable
•It is expensive.
•It is inflexible and not suitable for digital data
transmissions.
•It is easily tapped.
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50. Optical fiber cable
•It uses the concept of reflection of light through a
core made up of glass or plastic.
•The core is surrounded by a less dense glass or
plastic covering called the cladding. It is used for
transmission of large volumes of data.
•The plastic jacket is used to protect the cladding.
•Fibers are typically grouped in
bundle ,protect by outer sheath.
•Superior in data handling and
security.
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51. Advantages of optical fiber cable
•It is suitable for long data transmission with unlimited
bandwidth.
•They are much thinner and lighter
compared to others.
•Since data is transmitted in the form of light, it is
difficult to tap from middle.
•They are not affected by other
interference like electromagnetic interference.
Disadvantages
•They are not flexible than other cables, so
it is difficult to bend.
•They are expensive.
•It is difficult to connect two fiber optic cables.
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53. •A low frequency electromagnetic wave is called radio wave.
•Frequency below 1000MHz are radiofrequency .
•It is suitable for radio signal around earth surface.
•Ex: AM and FM.
Advantages :
➢It is inexpensive and easy to produce
➢It covers geographical area.
Disadvantages :
➢The data transfer rate is slower than that in wired media.
➢The quality of data transmission is very poor.
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54. Microwave
•High frequencies electromagnetic wave (1GHz to 300GHz) are
called microwaves.
•Microwaves travel in straight lines, and so the transmitter and
receiver stations should be accurately aligned to each other.
•Microwave propagation is line –of –sight propagation. So,
towers hoisting the stations should be placed so that the
curvature of the earth or any other obstacle does not interfere
with the communication.
•Since it is unidirectional, it allows multiple receivers in a row to
receive the signals without interference.
•Microwave is used in WAN , MAN ,satellite and telephone
communication .
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55. Advantages :
➢It has a high bandwidth than radio wave.
➢The quality of data transmission is better than radio wave.
Disadvantages
➢It cannot bend and pass obstacles so requires line of sight for
data transmission.
➢It does not cover very large space because of earth’s curvature.
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56. Data communication and networking 56

57. Advantages:
➢It covers the geographical area of earth .
➢It has higher bandwidth than radio or microwave data
transmission.
Disadvantages :
➢It is very expensive for installation and for maintenance.
➢It has signals experience propagation delay.
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58. Transmission impairments terminology
•Transmission impairment occurs when the received signal is
different from the transmitted signal.
•As we know, a signal can be transmitted as Analog signal or
it can be transmitted as a digital signal.
•In Analog signals due to transmission impairment the
resulting received signal gets different amplitude or the
shape.
•In the case of digitally transmitted signals at the receiver
side we get changes in bits (0's or 1's).
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59. Data communication and networking 59

60. Noise –
The random or unwanted signal that mixes up with the original signal is
called noise.
There are several types of noise such as-
Inducednoise comes from sources such as motors and appliances. These
devices act as sending antenna and transmission medium act as receiving
antenna.
Thermalnoise is movement of electrons in wire which creates an extra
signal.
noise is when one wire affects the other wire.
Impulsenoise is a signal with high energy that comes from lightning or
power lines
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61. Attenuation –
➢It means loss of energy.
➢The strength of signal decreases with increasing distance which causes loss
of energy in overcoming resistance of medium. This is also known as
attenuated signal.
➢Amplifiers are used to amplify the attenuated signal which gives the
original signal back and compensate for this loss.
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62. Distortion –
➢It means changes in the form or shape of the signal.
➢This is generally seen in composite signals made up with different
frequencies.
➢Each frequency component has its own propagation speed travelling
through a medium.
➢And that's why it delay in arriving at the final destination Every
component arrive at different time which leads to distortion.
➢Therefore, they have different phases at receiver end from what
they had at senders end.
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63. Crosstalk
➢Itis any phenomenon by which asignaltransmitted on
onecircuitorchannelof atransmission systemcreates an undesired
effect in another circuit or channel.
➢Crosstalk is usually caused by undesiredcapacitive,inductive,
orconductive couplingfrom one circuit or channel to another.
➢Crosstalk is a significant issue instructured cabling,audio
electronics,integrated circuit design,wireless communicationand
othercommunications systems.
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64. Jitter-
It refers to small intermittent delays during data transfers.
It can be caused by a number of factors including network
congestion,collisions, and signal interference.
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65. Echosand Singing-
➢Echoes and singing both occurs as a result of transmitted signals being
coupled into a return path and fed back to the respective sources.
➢Coupling will be zero only when perfect impedance matching occurs.
Impedance matching between trunks and subscriber loop (two wire
tofour wireat hybrid) is difficult due to various subscriber loop
lengths.
➢A signal reflected to the speaker's end of the circuit is called talker
echo and at the listener's end is called listeners echo. The talker echo
is more troublesome.
➢When the returning signal is repeatedly coupled back into the forward
path to produce oscillations, singing occurs.
➢Basically singing results if the loop gain at some frequency is greater
than unity.
➢An echo coming 0.5 msecafter the speech is not much effect.
➢The echoes with a round trip delay of more than 45 mseccannot be
tolerated.
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66. Packet Traceris across-platformvisualsimulation tool designed byCisco Systemsthat
allows users to createnetwork topologiesand imitate moderncomputer networks.
The software allows users to simulate the configuration of Cisco routers and switches
using a simulated command line interface.
Packet Tracer makes use of adrag and dropuser interface, allowing users to add and
remove simulated network devices as they see fit.
The software is mainly focused towards Certified Cisco Network Associate Academy
students as an educational tool for helping them learn fundamental CCNA concepts.
Network tool
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67. Remote Loginis a process in which user can login into remote
site i.e. computer and use services that are available on the
remote computer.
With the help of remote login a user is able to understand
result of transferring result of processing from the remote
computer to the local computer.
Aremote loginfacility permits a user to work on a program on
a distant computer based on valid login credentials.
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68. Network Connecting Devices
•Network connecting devices enables to interconnect the
computer in a network.
•Two or more devices are connected with each other for the
purpose of sharing data and resources form a network.
•Example :
➢Modem
➢NIC
➢repeaters
➢Hubs
➢Bridges
➢Routers
➢Gateway
➢Switches
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69. •Modem stands -"Modulator / Demodulator.“
•It is an electronic devices which translates data from digital
to analog and vice-versa.
•Modulation –convert digital to analog data.
•Demodulation –convert analog to digital data.
•It is used to connect internet via a telephone line which uses
analog signal where as computer uses digital signal.
•Internal modem /external modem.
MODEM
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70. •A network interface card (NIC) is a hardware component
without which a computer cannot be connected over a
network.
•It is a circuit board installed in a computer that provides a
dedicated network connection to the computer.
•It is also called network interface controller / network
adapter or LAN adapter.
•Each network interface card is uniquely identified by a
special number called MAC Address.
NIC
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71. •Hub is a multiport network connecting devices.
•A hubis the most basic networkingdevice that connects multiple
computers or other network devices together in a LAN.
•It accepts data ,amplifies and retransmit them to their destination.
•It is used in star topology.
•Unlike a networkswitchorrouter, a network hub has no routing
tables or intelligence on where to send information
andbroadcastsall network data across each connection.
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72. ▪A network switch is a smallhardwaredevice that centralizes
communications among multiple connected devices in onelocal area
network (LAN).
▪It is generally used in star topology.
▪Hub works on half -duplex whereas switch works on full-
duplex mode.
▪It has the capacity of inspecting the address of data packets
and directly switch the sources port to destination port.
▪Therefore its functionality is same as bridge so switch is also
known as multiport bridge .
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73. •Repeater is a signal amplifier device used to amplify weak signal into
its original signals.
•The main purpose of repeater is to extent the length of cable in a LAN
beyond the physical limit.
•It does not separate noise and data so , if noise is present ,it amplifies
noise with data.
•It links two similar ,type of LAN having same architecture.
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74. ➢A bridge is a type of computer network device that provides
interconnection with other bridge networks that use the same
protocol.
➢Bridges are similar to repeaters and hubs in that they broadcast
data to every node.
➢A bridges can send the data only to the concerned segment thus
preventing network traffic.
➢It is possible to connect two different network together like star
and ring topology network.
BRIDGE
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75. ➢Router is hardware and software devices.
➢A router is adevicethat forwards datapacketsalongnetworks.
➢It is highly intelligent and protocol sensitive linking devices used
to connect two different LANs or WANs.
➢Routers are located atgateways, the places where two or more
networks connect.
➢A router keeps tracks of the address of all segments of a
network and can even determine the best path for sending
data .
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76. GATEWAY
•A Gateway is an interconnecting device which connects two
different network protocols together which may be LANs and
WANs or two different LANs.
•It is much more complex and powerful than router .
•It combines the features of router and bridges.
•But slower than bridge and router because it connect entire
protocol of one network to other.
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77. BLUETOOTH
•Bluetooth is ashort-rangewireless
communication technologythat allows devices
such as mobile phones, computers, and
peripherals to transmit data or voice wirelessly
over a short distance.
•The purpose of Bluetooth is to replace the cables
that normally connect devices, while still keeping
the communications between them secure.
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78. Infrared Ray
•Infrared is a type of electromagnetic wave of large
wavelength and small frequencies than visible light.
•It frequency is low ,so it has small penetrating power.
•It is limited to small area or with in a room.
•Less expensive and does not require antenna.
•Application :
➢Mobile
➢Television remote
➢Home appliances etc..
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79. Wi-Fi
•Wi-Fi (wireless-fidelity) refers to the wireless
network which is standardized by IEEE.
•Wi-Fi is simply a trademark of the Wi-Fi alliance.
•Wi-Fi is a type of wireless networking protocol that
allows devices to communicate without cables or
cords.
•It is also called as WLAN (wireless Local area
network).
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80. OSI Reference Model of Networking
➢International standard organization (ISO) is multinational
body committed for the worldwide standardization of
products ,services and business.
➢There arennumbers of users who use computer network
and are located over the world.
➢So to ensure, national and worldwide data
communication, systems must be developed which are
compatible to communicate with each other .
➢ISOhas developed a standard model forOpen System
Interconnection(OSI) model in 1970’s.
➢ISO model is a layered based system that allow
communication between different types of network.
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81. lower layer
middle layer
Upper layer
OSI Reference Model of Networking
•An OSI REFERENCE model of network is certified model that entirely
describe how information is transmitted from an application of one
computer to another application of other computer.
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82. OSI Reference Model of Networking
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83. Some related Terms
1.Server
➢ It is the main computer in client-server or broadcasting
network architecture which manages and control all other
computers in the network.
➢ It is called as server because it provide services to other by
allowing the components to share expensive resources such as
storage device , printer etc.
a.File server
b.Print server
c.Modem Server
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84. 2.Client –
A device that make use of the services provided by a server.
3.Workstation –
In client –server network architecture , the clients are called as
workstation.
4.Internet and Intranet –
Intranetrefers to an internal network that utilizes the tools and
techniques of the internet to provide services limited to local
network users.
It is a private network group and owned by particular person of
organization.
Internet is a network of network. So it is the biggest network in
the world . It is public networking which can be accessed by
anybody who has access right.
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85. 5. IP address–
•It is a numerical label assigned to each device connected to
acomputer network that uses theInternet Protocolfor
communication.
•An IP address serves two main functions: host or network
interfaceidentificationand locationaddressing.
•Internet Protocol version 4(IPv4) defines an IP address as
a32-bitnumber.
•However, because of the growth of theInternetand
thedepletion of available IPv4 addresses, a new version of IP
(IPv6), using 128 bits for the IP address, was developed.
•Ex -192.168.1.15/24 (IPv6) , 172.16.254.1 (IPv4) etc.
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86. 6.MAC address ( media access control address) –
➢AMACis aunique identifierassigned to anetwork
interface controller(NIC) for use as anetwork addressin
communications within a network segment.
➢MAC addresses are recognizable as six groups of
twohexadecimal digits, separated by hyphens, colons, or
without a separator.
➢MAC addresses are primarily assigned by device
manufacturers, and are therefore often referred to as
theburned-in address, or as anEthernet hardware
address,hardware address, andphysical address.
➢Each address can be stored in hardware, such as the
card'sread-only memory, or by afirmwaremechanism.
➢Ex -12-34-56-78-9A-BC
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87. ForyourPatience
Data communication and networking 87