Network& Networking : Network& Networking By
Anurag Yadav
Deepak Verma
MBA ( IB )
What is a Network : 2 A Network is a group of Computers
connected together in a way that allows
information to be exchanged between the
computers. What is a Network
Why do we need a Network ? : If you own multiple PC’s; you have probably thought about how great it would be if you Computers talk to each other..
Share a single printer between computers
Share a single Internet connection among all the computers in your home
Play games that allow multiple users at different computers
. 3 Why do we need a Network ?
Advantages of a Network : Speed
Cost
Security
Centralized Management
Resource Sharing
Electronic Mail 4 Advantages of a Network
Disadvantages of a Network : Disadvantages of a Network Network faults can cause loss of data
Network fault can lead to loss of resources
User work dependent upon Network
System open to hackers
Decisions tend to become centralized
Network management can become difficult 5
OSI Model / Layer Functions : OSI Model / Layer Functions 6
TCP/IP Model / Layer Functions : TCP/IP Model / Layer Functions 7
Media ( Cables ) : Media ( Cables ) In Networking we use some effective cables like
Twisted pair : It is of two types
UTP ( Unshielded twisted Pair) for kilometers
STP ( shielded twisted pair) for backbone. 8
Twisted Pair Cable : Twisted Pair Cable Range -2-3 km with out amplifier
Bandwidth-56 kbps-100mbps
Resistances-50 ohm – 600 mhz..
Using RJ 45 WIRE CABLE..
Its DNA type.. twisted n more twisted.. 9
Co-axial Cable : Co-axial Cable It is Basically of two types :
50 Ohm – Digital (DTH)
75 Ohm — Analog (Cable TV)
Bandwidth — 600 Mbps
Range – 5- 20 Kms
Resistance – More then 600 MHz 10
Fiber Optics Cable : Fiber Optics Cable Bandwidth—3.8* 108 MBPs
Range—100 km
It is Unidirectional .. 450 Vertical angle Decoder , Encoder, Light Sources 11
Topologies of a Network : Topologies of a Network It refers to connecting to a logical or a Physical network.
It provides the facilities to how to connect the computer. It’s a process of connecting two and more devices. 12
Single Node Topology : Single Node Topology Single device at times called dumb terminal , connected to the server. Device operators on fills from server and returns them back after completing the task.
Advantages—Easy to Install, Configure and manage , least expensive ,single cable are required.
Disadvantages—Network consists of Single devices , dumb terminal depends on the Server. 13
Bus Topology : Bus Topology All devices are connected to a common cable called Backbone/Trunk. Operates in Daisy chain fashion. Devices are not responsible for terminate the data.
Advantages— Installation of devices is easy ,works better for smaller network
Disadvantages—if back bone breaks entire network gets down, difficult to Isolate problems. Limited number of devices can be attached. 14
Star Topology : Star Topology Each device is connected to a central device called Hub through a cable. Data passes through the Hub before reaching the destination.
Advantages—Easy to Configure, manage and expand , Centralized management
Disadvantages—Require more Cable, Failure of Hub affect entire network, more expensive. 15
Ring Topology : Ring Topology It is used in MAU [Multi Station Access Unit], devices are connected in closed loop. Most common type is token ring network.
Advantage — Reliable & offers greater speed, No collision.
Disadvantage—More cabling is required compared to Bus topology, one faulty device affects the entire network, adding devices affects the network. 16
Dual Ring Topology : Dual Ring Topology Uses only single ring at one time when rings at a time . When using primary then independent & when using primary then independent & when primary will damage then secondary will use. 17
Mesh Topology : Mesh Topology It is used in WANs to inter connect LANs. Every device is connected to every other device. Uses router to determines the best path of communication.
Advantage—Improve fault Tolerance, failure of one link does not affect entire network, Centralized mgmt is not required.
Disadvantage—difficult to install and manage, Each link from one device to other devices requires individual NIC. 18
Tree Topology : Tree Topology It is the combination of two topology..(Star-Bus),(Ring-Bus) ,Combination the characteristics of linear & star topology. Devices are wired to root hub. Twisted pair cable is commonly used.
Advantage-Easy to expand the network, point to point wiring for each device
Disadvantages-Difficult to configure if backbone is broken ,entire network goes down 19
Hybrid Topology : Hybrid Topology It combines two or more different physical topologies. Commonly Star-bus or Star –ring. It is also known as Special topology and is useful for Corporate offices. 20
Scope : Scope of
Network 21
LAN ( Local Area Network ) : A Computer network that spans a relatively
small area. Most LANs are confined to a
single building or group of buildings 22 LAN ( Local Area Network )
Hub : Hub A Hub is a shared device, meaning only one
Machine speaks at a time. All Connected
machines hear the broadcast , even if it isn’t
meant for them. This causes unnecessary
traffic slowing down the network. 23
Network Interface Card : Network Interface Card Often abbreviated as NIC , an expansion
board you insert into a computer so that the
computer can be connected to the network.
This also is known as Ethernet card &
Network Adapter. 24
Ethernet cable : Ethernet cable 25
MAN ( Metropolitan Area Network ) : MAN ( Metropolitan Area Network ) Metropolitan Area network , a data network
designed for a town or city. In terms of
geographic breadth , MANs are larger than
local-area networks ( LANs ) , but smaller
than wide-area networks ( WANs ). 26
Switch : 27 Switch A Switch is almost a Smart HUB. More than one
machine can speak at the same time and only the
intended recipients receive the data signal.
Wide Area Network ( WAN ) : 28 A computer network that spans a relatively large
geographical area. Typically a WAN consists of
two or more Metropolitan-Area Networks
( MANs ). The largest WAN in existence is the
Internet. Wide Area Network ( WAN )
Routers : 29 Routers A Device that forwards data packets along
networks. A router is connected to at least two
networks , commonly two LANs or WANs or a LAN
and its ISPs network.
Client Server Architecture : 30 Client Server Architecture A network architecture in which there is one
Service (Provider) and all other systems
work as Clients (Requestor).
Protocols : Protocols An agreed upon Set of Rules for transmitting
data between two devices. One common
protocol on any network is TCP/IP. 31
Transmission Control Protocol/Internet Protocol : Transmission Control Protocol/Internet Protocol TCP breaks data into packets and
establishes connection between the Host
and the Destination.
IP addresses the packet and works with
TCP to end data back & forth on a network. 32
How a Data Packet looks… : How a Data Packet looks… Header Sender’s IP address
Receiver’s IP address
Protocol
Packet number
Payload Data
Trailer Data to show end of
packet Error
correction 33
IP Address : IP Address Every machine on the Internet has a unique
identity , called am IP Address . A typical IP
address looks like this :
E.g. : 216.27.61.137
The four parts in an IP address are called
octets. 34
IP Address Classification : IP Address Classification The Octets serve a purpose other than
simply separating the numbers. They are
used to create Classes of IP addresses. The
first Octet is used to identify the class of the
IP.
Class A 0 – 126
Class B 128 – 191
Class C 192 – 223
E.g. : 145.125.66.45 is a Class B IP Address 35
Subnet Mask : Subnet Mask An IP Address has two components , the
network address and the host address.
A Subnet mask is used to distinguish
between the two addresses.
N/W address the identifies the network and
the Host address identifies a particular
system in that network. 36
Class Related Subnet Mask : Class Related Subnet Mask Class Subnet Mask
A ----------------------------> 255.0.0.O
B ---------------------------- > 255.255.0.0
C -----------------------------> 255.255.255.0 37
Example : : Example : 145.24.53.107
145 is a Class B IP Address
The Subnet Mask for Class B is 255.255.0.0
145.24.53.107 145.24 is masked by 255.255 – N/W ID
255.255.0.0 53.107 is masked by
0.0 – Host ID 38
Network ID Host ID : Network ID Host ID 169.34.75.99 -- 168.34 75.99
46.153.44.75 -- 46 153.44.75
213.45.65.66 -- 213.45.65 66
143.54.65.22 -- 143.54 65.22 39
Types of IP Adresss : Types of IP Adresss Dynamic IP Static IP
A Dynamic IP address A Static IP Address
is one that is temporarily is an IP address
Assigned to a user by assigned by a
their Internet Service Service provider
provider every time that never changes.
they connect. 40
Addressing Guidelines : Addressing Guidelines The First Number in the Network ID cannot be 127.
127.0.0.1 is a Loop back ID that is used to test the Network connection.
The IP Address cannot be all 255s.
255.255.255.255 – to Broadcast a message to all systems on a Network.
The Host ID cannot be all Zeros
Two computers on a network cannot have the same host ID. 41
Stand Alone IP Address : Stand Alone IP Address A System that is not connected to any network is called a ‘ Stand Alone System ‘
The IP addresses
0.0.0.0
169.254.x.y ( where ‘x’ and ‘y’ can be any value ) denote Stand Alone Systems. 42
DHCP Server : DHCP Server Short for Dynamic Host Configuration Protocol , a protocol for assigning dynamic IP addresses to devices on a network. A Server that works on this protocol is known as a DHCP Server.
Three information that a DHCP Server provides a system on a Network are :
Dynamic IP Address
DNS Information
Default Gateway 43
DNS : DNS Short for Domain name System ( or Service or Server ), an Internet service that translates Domain names into IP addresses. The Internet however , is really based on IP addresses. DNS translates the domain name into the corresponding IP address.
Domain Name IP Address
www.yahoo.com -- DNS - - 66.95.234.13 44
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