2. What is computer networking
Computer networking means sharing of data &
resources between two or more computer with a
communication between them. The communication
medium can be through wires, radio waves, leased line,
infra-red, optical fiber etc.
The main purpose of networking is sharing of data &
3. Advantages of Networking
Sharing Hardware resources
Sharing software resources
4. Disadvantage of Networking
If fault occur in the server then all the clients are failed
to access software's from server.
Network fault can cause lose of Data & resources.
System open to hackers.
User work dependent up on network.
5. Advantage of Networking
Hardware and Software Sharing
6. Networking Devices
NIC (Network Interface Card) :-
A card installed in a computer that unable the computer to
communicate a network. All NIC implement a networking standards
called Ethernet Every client & server must have a network interface
card in order to be a part of network.
computers in a network are physically connected to each other using
Network cables usually does not connect computer directly to each
other. Instead of this, Each computer connected by a cable to a device
known as hub or switch. The hub or switch connect rest of the network.
Each switch contain certain no of port typically 8,16,24 etc.
Typically server computer use a special software in order to function
efficiently & the client computer needs to have their setting
configuration in order to access to the network.
Network software is used to efficiently shar information.
modem is the combination of two word modulation &
demodulation. Modem is a device which convert analog
signal to digital signal & vice versa.
A router is a device that forwards data packets along
networks. The router used to connect two or more
networks & uses multiple paths to send & receive data.
sometimes router is also called gateway.
Access point act as an interface cable network & wireless
device. We can also connect nodes(computer) to a access
Repeaters are used maintain the strength of the signal
constant. Hub, Switchs, routers are also acts as a repeater.
8. Difference Between Switch & Hub
It is manageable. It is not manageable.
It works on the 1st layer of It works on the 2nd layer of
OSI reference model. OSI reference model.
Collision detection is turned Collision detection is not
on. turned on.
Operates on half Duplex Operates on full duplex mode.
9. Different Modes of Communication
Unicast:-one sender one receiver
Multicast:- one sender multiple devices are the
receiver but not all
Broadcast:-One sender all other devices are receiver.
Carrier Sense Multiple Access With Collision
detection(CSMA/CD) is a protocol that is implemented in bus
topology. It is divided into three part:-
Multiple access refers to the fact that in bus system. Each
Station has access to the common cable.
It refer to the fact that each station listen to see if no other
station are transmitting before sending.
It refers to the principal of listening if other station are
transmitting While we are transmitting.
11. The OSI (Open Systems
Interconnection) Data Model
ISO standard for computer networks design and
Involves at least 7 layers, each playing a specific
role when applications are communicating over
13. Physical layer:- It ensures a safe and efficient travel
of data; consists of electronic circuits for data
transmission etc. The physical layer defines the
electrical, mechanical specification for maintaining,
activating, deactivating physical link between end
Data link layer:- It is in charge of data encapsulation
under the form of packets. The data link layer
defines how data is formatted for transmission
how access to the network is control.
14. Network layer:- It is in charge of packets transmission
from a source A to destination B. Network layer
provides connectivity &path selection between two
communicating host system that might be located
on two different network.
Transport layer:- It is in charge of the delivery of
packets from a source A to a destination B. The
transport layer segments data packets from the
sending host system & reassemble the data in a data
stream on the receiving host system.
Session layer:- It is in charge of the management of
network access. The session layer establish, manages
session between two communicating host system.
15. Presentation layer:- It determines the format of the data
transmitted to applications, data compressing
decompressing, encrypting etc. The presentation layer
ensures the information that the application layer of one
system sends out is readable by the application layer of
Application layer:- It contains the applications which are used
by the end user, such as Java, Word etc. It provides network
services to user application. It does not provide services to
any other OSI layer.
The two most popular types of network cabling are
twisted-pair (also known as 10BaseT) and thin coax
(also known as 10Base2) & Optical Fiber. 10BaseT
cabling looks like ordinary telephone wire, except that
it has 8 wires inside instead of 4. Thin coax looks like
the copper coaxial cable.
In this type of cabling wires are twisted to each other.
This help to reduce the electromagnetic induction.
When 10BaseT cabling is used, a strand of cabling is
inserted between each computer and a hub. If you have
5 computers, you'll need 5 cables. Each cable cannot
exceed 325 feet in length. Because the cables from all
of the PCs converge at a common point, a 10BaseT
network forms a star configuration. RJ45 connectors
are used in this type of cabling.
10BASE2 coax cables had a maximum length of 185 meters
(607 ft). The maximum practical number of nodes that can
be connected to a 10BASE2 segment is limited to 30. In a
10BASE2 network. The geometric design that is formed
when thin coax cabling is used is called a linear or
backbone configuration. The reason for this is that thin
coax is always arranged in a straight line of PCs, hubs, or
other devices. Thin coax networks always require
termination. In a 10BASE2 network, each segment of cable
is connected to the transceiver (which is usually built into
the network adaptor) using a BNC T-connector, with one
segment connected to each female connector of the T.
27. Optical Fiber Cable
An optical fiber (or optical fibre) is a flexible,
transparent fiber made of glass (silica) or plastic,
slightly thicker than a human hair. Optical fiber can be
used as a medium for telecommunication
and computer networking because it is flexible and
can be bundled as cables. It is especially advantageous
for long-distance communications. The most
commonly used fiber optic cable is a multi-mode fiber
cable (MMF) with a 62.5 micron fiber optic core .
Single-mode fiber, another kind of cabling, is more
efficient than multi-mode, but far more expensive.
Maximum length is up to 25 km & speed is up to 2 gb.
29. Network Models
Peer-to-Peer - A peer to peer network is one in which
there is no dedicated server and every computer acts
as both a client and a server. This is a good networking
solution when there are 10 or less users .
This type of network is designed to support a large
Number of users and uses dedicated server(s) to
accomplish this. Clients log on to the server(s) in order
to run applications or obtain files.
31. Types of networks
Local Area Network(LAN):-
A local area network (LAN) is a computer network that spans
a relatively small area, such as a single office or office
building, and typically offers high-speed communications.
Metropolitan Area Networking(MAN):-
A MAN is a computer network that usually spans with in a
large campus or a city. A MAN usually interconnect no of
Wide Area Networking(WAN):-
A wide are a network (WAN) computer network that spans
a relatively large geographical area. Computers connected
to a wide-area network are often connected through public
networks, such as the telephone system, leased lines
(ISDN), satellite, microwave, or other connection method.
32. Wireless Local Area Network(WLAN):-
A communications network that provides connectivity to
wireless devices within a limited geographic area. "Wi-Fi" is
universal standard for wireless networks and is the wireless
equivalent of wired Ethernet networks.
Storage Area Network(SAN) :-
A SAN is a network of storage devices that can be accessed
by multiple computers. Each computer on the network can
access hard drives in the SAN as if they were local disks
connected directly to the computer. This allows individual
hard drives to be used by multiple computers, making it
easy to share information between different machines.
personal area network(PAN):-
A personal area network(PAN) is a computer network
organized around an individual person. Personal area
networks typically involve a mobile computer, a cell
phone . You can use these networks to transfer files
including email and calendar appointments, digital
photos and music. typically within 10 meters or 33 feed).
In computer networking topology refers to the layput
or design of connected devices.
Physical Topology:- It refers to the physical design of
the network including the devices, location & cable
Logical Topology:-It refers to the fact that how data
actually transfers in a network as opposed to its
37. Different Types of Topologies
38. Bus Topology
All the nodes (file server, workstations, and
peripherals) on a bus topology are connected by one
A bus topology consists of a main run of cable with a
terminator at each end. All nodes (file
server, workstations, and peripherals) are connected to
the linear cable.
Popular on LANs because they are inexpensive and
easy to install.
40. Bus Topology
Advantages of Bus Topology
It is Cheap, easy to handle and implement.
Require less cable
It is best suited for small networks.
Disadvantages of Bus Topology
The cable length is limited. This limits the number of
stations that can be connected.
This network topology can perform well only for a
limited number of nodes.
41. Ring Topology
In a ring network, every device has exactly two neighbours
for communication purposes.
All messages travel through a ring in the same direction.
A failure in any cable or device breaks the loop and can
take down the entire network.
To implement a ring network we use the Token Ring
A token, or small data packet, is continuously passed
around the network. When a device needs to transmit, it
reserves the token for the next trip around, then attaches
its data packet to it.
43. Ring Topology
Advantage of Ring Topology
Cable faults are easily located, making troubleshooting
Ring networks are moderately easy to install
Easier to Mange than a Bus Network
Disadvantages of Ring Topology
The failure of a single node of the network can cause
the entire network to fail.
A single break in the cable can disrupt the entire
44. Star Topology
In a star network, each node (file server, workstations, and
peripherals) is connected to a central device called a hub.
The hub takes a signal that comes from any node and
passes it along to all the other nodes in the network.
Data on a star network passes through the hub, switch, or
concentrator before continuing to its destination.
The hub, switch, or concentrator manages and controls all
functions of the network.
The star topology reduces the chance of network failure by
connecting all of the systems to a central node.
46. Star Topology
Advantages of Star Topology
Easy to manage
Easy to locate problems (cable/workstations)
Easier to expand than a bus or ring topology.
Easy to install and wire.
Easy to detect faults and to remove parts.
Disadvantages of Star Topology
Requires more cable length than a linear topology.
If the hub or concentrator fails, nodes attached are
47. Tree Topology
A tree topology (hierarchical topology) can be viewed
as a collection of star networks arranged in a hierarchy.
Tree Topology is also called the combination of bus
topology & star Topology
This is particularly helpful for colleges, universities and
schools so that each of the connect to the big network
in some way.
49. Tree Topology
Advantages of a Tree Topology
Point-to-point wiring for individual segments.
All the computers have access to the larger and their
Disadvantages of a Tree Topology
Overall length of each segment is limited by the type of
If the backbone line breaks, the entire segment goes down.
More difficult to configure and wire than other topologies
50. Mesh Topology
In this topology, each node is connected to every other
node in the network.
Implementing the mesh topology is expensive and
In this type of network, each node may send message
to destination through multiple paths.
While the data is travelling on the Mesh Network it is
automatically configured to reach the destination by
taking the shortest route which means the least
number of hops.
52. Mesh Topology
Advantage of Mesh Topology
No traffic problem as there are dedicated links.
It has multiple links, so if one route is blocked then other
routes can be used for data communication.
Points to point links make fault identification easy.
Disadvantage of Mesh Topology
There is mesh of wiring which can be difficult to manage.
Installation is complex as each node is connected to every
Cabling cost is high.
53. Hybrid Topology
A combination of any two or more network topologies.
A hybrid topology always accrues when two different
basic network topologies are connected.
It is a mixture of above mentioned topologies.
Usually, a central computer is attached with sub-
controllers which in turn participate in a variety of
56. IP Address
Internet Protocol Address (or IP Address) is an unique
address that computing devices use to identify itself and
communicate with other devices in the Internet Protocol
network. Any device connected to the IP network must
have an unique IP address within its network.
IP address is a 32 bit number that is used to uniquely
identify a computer on a network.
57. Subnet Mask
An IP address has two components, the network address and the
host address. A subnet mask separates the IP address into the
network and host addresses (<network><host>). A Subnet mask
is a 32-bit number that masks an IP address, and divides the IP
address into network address and host address. Subnet Mask is
made by setting network bits to all "1"s and setting host bits to
all "0"s. Within a given network, two host addresses are reserved
for special purpose. The "0" address is assigned a network
address and "255" is assigned to a broadcast address, and they
cannot be assigned to a host.
58. Default Gateway
Computer can communicate directly with the other
computer on the same network. The only way to
communicate with a computer on the different
network is through a router(internetworking). The
default gateway represents the IP address of the router
that is used to communicate outside of its network.
61. IP Address ranges
Example:- 126.96.36.199 (IP address)
255.0.0.0 (Subnet mask)
Binary value of subnet mask
Total no of host=2^n=2^24=16777216
Total no of valid host=2^n-2=16777214
n=Total no of Host bit
1 represents for network bits & 0 represents for Host bits
62. IP Address ranges
Example:- 188.8.131.52(IP address)
255.255.0.0 (Subnet mask)
Binary value of subnet mask
Total no of host=2^n=2^16=65536
Total no of valid host=2^n-2=65534
n=Total no of Host bit
1 represents for network bits & 0 represents for host bits
63. IP Address ranges
Example:- 192.0.0.1(IP address)
255.255.255.0 (Subnet mask)
Binary value of subnet mask
Total no of host=2^n=2^8=256
Total no of valid host=2^n-2=254
n=Total no of Host bit
1 represents for network bits & 0 represents for host bits
64. private IP addresses
The Internet Assigned Numbers Authority (IANA) has
reserved the following three blocks of the IP address
space for private local networks:-
10.0.0.0 - 10.255.255.255
172.16.0.0 - 172.31.255.255
192.168.0.0 - 192.168.255.255
65. Public IP address
An IP address is considered public if the IP number is
valid and falls outside any of the IP address ranges
reserved for private uses by Internet standards groups.
All the computer connected to the internet must have
unique IP address other than the private IP address.
The IP address which is used in publicly for example
internet & we have to pay money for that to the service
66. Other reserved IP address
127.0.0.0-127.255.255.255 is reserved for diagnostic &
IP addresses in the range of 169.254.0.0 -
169.254.255.255 are reserved for Automatic Private
67. Setting the IP address
Click Start > Control Panel.
On the control panel, double-click Network Connections.
Right-click Local Area Connection.
Select Internet Protocol (TCP/IP), and then
Select Use the Following IP Address.
Specify the IP address, Subnet mask, and Default
gateway (If available)
Click OK on the Local Area Connection Properties window.
68. Intranet & Extranet & Internet
If the Network is spans with in a office building then it
is called intranet.
If two different networks are connected through the
internet it is called extranet.
Interconnection of many Computer networks is called
Internet. It is a international Computer network.
70. Uniform Resource Locator (URL)
It is used to locate the resource in the network.
Protocol used (http://)
DNS address (example.microsoft.com)
Path on the server (/tutorial/default.html
71. Networking Protocols
Protocol:- A set of rules or guidelines that are used in
networking is called protocol.
Some of the networking protocols are:-
It is combination of two protocols one is TCP another
is IP. TCP is the connection oriented reliable protocol.
It is responsible for breaking the messages into
segments & reassembling them at the destination
station, resending any thing that is not received. The
internet protocol handles the address part of the
packets so that it gets to the right destination.
72. ICMP( Internet Control Message protocol):-
It is a networking protocol that is used by the operating
system of network computer to send error message.
Example:- Destination host unreachable
Pop3(post Office Protocol) , IAMP( Internet Control
Message Protocol) & SMTP(Simple Mail transfer
These protocols are used for email retrieval virtually in the
Telnet( terminal Emulation):-
It is a protocol used for remotely accessing the computer of
the another network.
73. ARP - provides IP-address to MAC address resolution
for IP packets. A MAC address is your computer's
unique hardware number and appears in the form 00-
A0-F1-27-64-E1 (for example).
FTP - File transfer protocol is used for transferring
files between remote systems. Must resolve host name
to IP address to establish communication
HTTP - The Hypertext Transfer Protocol is the set of
rules for exchanging files (text, graphic images, sound,
video, and other multimedia files) on the World Wide
Web. It is the protocol controlling the transfer and
addressing of HTTP requests and responses.
74. Internet protocol suite
The Internet protocol suite is the set
of communications protocols used for the Internetand
similar networks, and generally the most
popular protocol stack for wide area networks. It is
commonly known as TCP/IP, because of its most
important protocols: Transmission Control
Protocol (TCP) and Internet Protocol(IP), which were
the first networking protocols defined in this standard.
TCP/IP provides end-to-end connectivity specifying
how data should be
formatted, addressed, transmitted, routed and received
at the destination. It has four abstraction layers, each
with its own protocols.
75. The layers are:
1. The link layer (commonly Ethernet) contains
communication technologies for alocal network.
2. The internet layer (IP) connects local networks, thus
3. The transport layer (TCP) handles host-to-host
4. The application layer (for example HTTP)
Firewall is any hardware or software that is designated
to prevent the unwanted networking traffic.
Firewall can block the information entering to &
getting out from the network.
NetMeeting provides people around the world with a
new way of communicating. Users can work together
on virtually any Windows-based application, exchange
or mark up graphics on an electronic
whiteboard, transfer files, or use the text-based chat
program. To install Net meeting goes to star then run
type conf & then ok
79. IIS( Internet Information Service)
IIS is web server software that provides
integrated, reliable, secure, and scalable software for
creating and managing internal corporate websites and
external websites on the internet. IIS is not installed
80. Creating IIS server
Create a folder on a drive.
Under this folder create a text file & write down something.
Then rename the file with .html extension name.
Go to IIS from
start=> programs=>Administrative tools=>IIS=>expand the on
computer name & then right click on website=>new=>specify the
description of website =>next=>next=>browse the .html file
path=> then click on finish.
Then right click on website you created
=>properties=>documents=>click on add=>give the html file
name=>ok=>click on move up=>apply=>ok
On the client side to access the website go to internet explorer
type http://IP Address or DNS name
DHCP ( Dynamic Host Configuration protocol). DHCP is a
protocol used to assign the IP address automatically.
In a large corporate where the no of computers are more, it
is difficult to assign the IP addresses automatically. That’s
why we are using DHCP server to assign the IP addresses
DHCP releases & renews the IP addresses as devices
leave & rejoin the network.
84. Advantage Of DHCP
DHCP reduce the effort of administrator.
Reduce the time of providing IP address.
Reduce the conflict in networking
There is no need to assign IP addresses to each
85. Disadvantage Of DHCP
When a client location is change or another computer is
connect in the place of that computer. In that case the IP
address is changed.
86. Install DHCP server service on
Windows Server 2003
Insert the Windows server 2003 CD
Go to Start > Control Panel > Add or Remove Programs .
When the Add or Remove Programs window
launches, click Add/Remove Windows Components in the
When the Windows Components Wizard comes up, scroll
down and highlight Networking Services and then click
the Details button.
When the Networking Services window comes up, place a
check mark next to Dynamic Host Configuration Protocol
(DHCP) and click OK and OK again.
87. Configure DHCP on Windows
Start > Administrative Tools > DHCP
Right-click the server node in the left pane and
choose New Scope . This will launch the New Scope
On the New Scope Wizard, click Next
Specify a scope name and scope description.
Specify an IP address range and subnet mask. For
the Start IP address enter 192.168.0.1, for the End IP
address enter192.168.0.254 . Finally, specify
a subnet mask of 255.255.255.0 and click Next.
88. Specify IP addresses to exclude from assignment.
click Add , and then click Next. The IP address of DHCP
server should be in the exclude List
Specify the lease duration for the scope. Verify
that Days is 8 and click Next.
Configure DHCP Options. Make sure “ Yes, I want to
configure these settings now ” is selected and
click Next to begin configuring DHCP options.
Specify the router IP address and then click Next . If the
router is available.
Configure domain name and DNS servers.(If available)
Configure WINS servers. On the next screen(If available)
Finally, the wizard asks whether you want to activate the
89. DNS(Domain Name System)
Every network requires a mechanism to resolve
computer names to Internet Protocol (IP) addresses.
DNS is a mechanism for converting computer name to
IP address also IP address to computer name.
It works on two Zones. These are forward look up zone
& reverse Look up zone.
Forward look up zone convert computer name to IP
Reverse look up zone convert IP address to computer
90. Installing DNS
Insert the CD of Windows server 2003.
Click Start, click Control Panel, and then click Add or
Click Add/Remove Windows Components.
select the Networking Services check box, and then
In Subcomponents of Networking Services, select
the Domain Name System (DNS) check box, click OK,
and then click Next.
91. Configuring DNS
Then select DNS
Expand the computer name.
Right click on Forward kook up zone
Select new zone Then click on Next-Next-Next
Then Specify the zone Name With a .com extention
Click on Next &Then finish.
92. Domain Controller
A domain controller is a server that is running a version of
the Windows Server operating system and has Active
Directory Services installed.
In Windows Server 2003 and Microsoft
Windows 2000 Server, the directory service is named
Active Directory serve as a central location for
administration & security.
A Microsoft active directory, in simple terms, is like a
telephone book that organizes within it all of the computers
and people that have been entered into it.
To install Active directory services Go to Start-run type
93. Benefits of a Domain
Organized Easy Location of
User1 Computer1 User2 Printer1
94. Features of a Domain
can not log on to the
Centralized Management Scalability
95. Backup Domain Controller
Backup Domain Controller (BDC) is a computer that
has a copy of the user accounts database. Unlike the
accounts database on the Primary Domain
Controller (PDC), the BDC database is a read only copy.
When changes are made to the master accounts
database on the PDC, the PDC pushes the updates
down to the BDCs
Most domains will have at least one BDC, often there
are several BDCs in a domain. These additional domain
controllers exist to provide fault tolerance. If the PDC
fails, then it can be replaced by a BDC.
96. Child Domain Controller
For DNS and Active Directory, a domain located in the
namespace tree directly beneath another domain (the
parent domain). For example, example.microsoft.com
would be a child domain of the parent domain
microsoft.com. Also known as a sub domain.
A child domain is a member domain of a Windows
Active Directory directory service but is not the root
domain of that Active Directory.
The main purpose of child domain is load balancing.
97. Domain, Tree & Forest
A domain is the core administrative unit of the
Windows Server 2003 directory service. However, an
enterprise may have more than one domain in its
A tree contain multiple domains with contiguous DNS
A forest is the combination of multiple trees.
98. Domain Naming
99. Remote Desktop
Remote Desktop allows you to access your computer
from a remote location.
The Remote Desktop Connection client software (for
the computer from which you want to connect) is
installed by default on all computers running Windows
7, Vista, or XP.
For using remote desktop connection. The remote
desktop connection must be enabled in the host
100. Enable the Remote Desktop
feature on your host computer
1. From the Start menu, select Control Panel (or Settings, and
then Control Panel). Double-click System.
2. In Windows 7 and Vista, click Remote settings. In the "Remote
Desktop" section, select one of the two options to allow
connections from other computers. In Windows XP, select
the Remote tab. Select Allow users to connect remotely to
3. To choose which users will have remote access, in 7 and Vista,
click Select Users... or in XP, click Select Remote Users... .
Typically, all administrators of the computer will have access
by default. Each user must have a password before you can
allow remote access.
4. When you are finished, click OK. Your computer will now be
able to accept incoming Remote Desktop connections.
101. How to Get Remote Desktop
Start => All Programs => Accessories =>
Communications, => Remote Desktop Connection
Then give the IP address of the computer that you want
102. Internet Connection Sharing
ICS offers a simple way to configure computers in a small
home office network to share a single Internet connection.
For small networks, ICS offers a cost-effective way to provide
Internet access to multiple computers.
The IP addresses of the computers on the network must also
be in the 192.168.0.x range, and the subnet mask must always
be 255.255.255.0. If network computers cannot use these
addresses, ICS does not work properly.
When you enable ICS, the ICS computer configures itself with
the IP address 192.168.0.1 and also becomes a DHCP server
for the network, so that it can provide IP addressing
information to other computers.
104. ICS using Ccpooxy software
Download CCProxy from the download center, run
ccproxysetup.exe and keep clicking the "Next" button to
finish the installation.
Launch CCProxy on the server for Internet connection
After set up proxy server with CCProxy, you can create
accounts and specify the authentication type for your own
proxy server in the "Account Manager" dialog box of
There are 2 authentication types for you to select:
Anonymous - please select "Permit All" for "Permit
105. Authentication required - please select "Permit Only"
for "Permit Category" and then select proper "Auth
Type" as you wish.
CCProxy supports several authentication types such as
"IP Address", "MAC Address", "User/Password" and
some combined auth types as you can see in the
"Account Manager" dialog box. For Internet connection
sharing, we recommend "IP Address" authentication
106. Make proxy server settings for IE
Go to client computer and open IE properties by right
clicking on Internet explorer.
Select "Connections" tab, click "LAN Settings" button
and open the "Local Area Network(LAN) Settings"
Check "Use a proxy server for your LAN", Fill
"192.168.0.1" in "Address" and "808" in "Port"
Click "OK" button in "Local Area Network (LAN)
Settings" and "Internet Options" dialog boxes.
Now you can browser Internet web sites in IE at the