SlideShare a Scribd company logo
A
Seminar Report
On
TCP-IP
Submitted to
The Rajasthan Technical University
In partial fulfillment of the requirements of the
Award of the Degree
Of
Bachelor Of Technology (Information Technology)
KAUTILYA INSITUTE OF TECHNOLOGY AND ENGINEERING
JAIPUR
Submitted to: Submitted By:
Mr. Chetan Kumar Ayush Bilala
(Dept. Head) Roll No. 07EKTIT013
B-Tech 4th
Year,8th
Sem
Department Of Information Technology
Kautilya Institute Of Technology And Engineering
Affiliated To
Rajasthan Technical University, Kota
2010-2011
2
AACCKKNNOOWWLLEEDDGGMMEENNTT
This seminar report could not have been prepared without the
help and encouragement from various people. Hence for the same
reason I would like to thank my faculties without whom this report
would have been a difficult task. It was for support that I got proper
guidelines preparing my presentation . I would also like to thank my
everyone who helped me directly or indirectly.
KRIPASHANKAR SHARMA
(07EKTIT013)
3
CCOONNTTEENNTT
01. ABSTRACT««««««««««««««4
02. INTRODUCTION............................................ 5
03. TCP-IP BASICS««««.«««««««.. 6
03.1 Origin of TCP-IP
03.2 TCP-IP and Intranets
03.3 Basic Function of TCP-IP
03.4 User Datagram protocol
03.5 Other important protocols
04. TCP-IP ARCHITECTURE«..««««««12
04.1 Flowing of data through each layer
04.2 Transmission of data in real world n/w
05. ACRONYMS««..«««««««««««16
06. CONCLUSION««««««««««««...18
07. BIBLIOGRAPHY««.««««««««.....19
4
11.. AABBSSTTRRAACCTT
One of the most important achievement of last decade is popularity of
internet. Today internet has become part of our day to day life.TCP/IP in a
broad sense can be explained as the concept on which internet works.The paper
attempts to familiarize with some of the basic concepts of TCP/IP.
It starts with a brief introduction of TCP/IP and provides the basics of it.It
also gives a brief origin of TCP/IP and the basic function of these protocols.It
also gives the structure of TCP/IP and explains how transmission of data takes
place in real world network.It also gives description of some of the protocols
that constitute TCP/IP.The conclusion summarizes the key points of TCP/IP.
5
22.. IINNTTRROODDUUCCTTIIOONN
Most of us know of TCP/IP as the glue that binds the Internet. But not as
many can offer a cogent description of what it is and how it works. So what is
TCP/IP, really?
TCP/IP is a means for networked computers to communicate with each
other. It doesn't matter whether they are part of the same network or are
attached to separate networks. It doesn't matter if one computer is a Cray and
the other a Macintosh. TCP/IP is a platform-independent standard that bridges
the gap between dissimilar computers, operating systems, and networks. It's the
protocol that drives the global Internet, and it is to the Internet that TCP/IP owes
much of its popularity.
Understanding TCP/IP is largely a matter of understanding a collection of
arcane protocols that TCP/IP hosts use to exchange information. Let's look at
some of those protocols and see what makes TCP/IP tick
.
6
33.. TTCCPP--IIPP BBAASSIICCSS
TCP/IP stands for Transmission Control Protocol/Internet Protocol. In
networking terms, a protocol is an agreed-upon standard that permits two
computers to exchange data. TCP/IP isn't just one protocol, but several. That's
why you'll often hear it referred to as a protocol suite, of which TCP and IP are
the two principal protocols.
The TCP/IP software that you install on a computer provides platform-
specific
implementations of TCP, IP, and other members of the TCP/IP family.
Typically, it also includes high-level application programs, such as FTP (File
Transfer Protocol), which permits users to perform network file transfers from
the command line.
7
3.1) ORIGIN OF TCP/IP
TCP/IP is an outgrowth of research funded by the U.S. government's
Advanced Research Projects Agency (ARPA) in the 1970s. It was developed so
that research networks around the world could be joined to form a virtual
network known as an internetwork.
The original Internet was formed by converting an existing
conglomeration of networks, known as ARPAnet, over to TCP/IP; that Internet
would eventually become the backbone of today's Internet.
8
3.2) TCP/IP AND INTRANETS
The reason TCP/IP is so important today is that it allows standalone
networks to be connected to the Internet or linked together to create private
intranets. The networks that comprise an intranet are physically connected by
devices called routers or IP routers. A router is a computer that transfers
packets of data from one network to another. On a TCP/IP intranet, information
travels in discrete units called IP packets or IP datagrams. TCP/IP software
makes each computer attached to the network a sibling t o all the others; in
essence, it hides the routers and underlying network architectures and makes
everything seem like one big network. Just as connections to an Ethernet
network are identified by 48-bit Ethernet IDs, connections to an intranet are
identified by 32-bit IP addresses, which we express as dotted decimal numbers
(for example, 128.10.2.3). Given a remote computer's IP address, a computer on
an intranet or the Internet can send data to the remote computer as if the two
were part of the same physical network.
9
3.3) BASIC FUNCTION OF TCP AND IP
TCP/IP provides a solution to the problem of how two computers
attached to the same intranet but belonging to different physical networks can
exchange data. The solution comes in several parts, with each member of the
TCP/IP protocol suite filling in one piece of the puzzle. The most fundamental
TCP/IP protocol, IP, transmits IP datagrams across an intranet and performs an
important function called routing--choosing the path that datagrams will follow
to get from A to B and using routers to "hop" networks.
TCP is a higher-level protocol that allows applications running on
different hosts to exchange data streams. TCP divides data streams into chunks
called TCP segments and transmits them using IP. In most cases, each TCP
segment is sent in a single IP datagram. If necessary, however, TCP will split
segments into multiple IP datagrams that are compatible with the physical data
frames that carry bits and bytes between hosts on a network. Because IP doesn't
guarantee that datagrams will be received in the same order in which they were
sent, TCP reassembles TCP segments at the other end to form an uninterrupted
data stream. FTP and telnet are two examples of popular TCP/IP applications
that rely on TCP.
10
3.4 USER DATAGRAM PROTOCOL
Another important member of the TCP/IP suite is the User Datagram
Protocol (UDP), which is similar to but more primitive than TCP. TCP is a
"reliable" protocol because it performs the error-checking and handshaking
necessary to verify that data makes it to its destination intact. UDP is an
"unreliable" protocol because it doesn't guarantee that datagrams will arrive in
the order in which they were sent or even that they will arrive at all. If reliability
is desired, it's up to the application to provide it.
Still, UDP has its place in the TCP/IP universe, and a number of
applications use it. The SNMP (Simple Network Management Protocol)
application provided with most implementations of TCP/IP is one example of a
UDP application.
11
3.5) OTHER IMPORTANT PROTOCOLS OF TCP/IP :
Other TCP/IP protocols play less visible but equally important roles in
the operation of TCP/IP networks. For example, the Address Resolution
Protocol (ARP) translates IP addresses into physical network addresses, such as
Ethernet IDs. A related protocol, the Reverse Address Resolution Protocol
(RARP), does the opposite, converting physical network addresses into IP
addresses.
The Internet Control Message Protocol (ICMP) is a support protocol that
uses IP to communicate control and error information regarding IP packet
transmissions. If a router is unable to forward an IP datagram, for example, it
uses ICMP to inform the sender that there's a problem. For a summary of some
of the other protocols that fall under the TCP/IP umbrella, see the sidebar
above.
12
4. 4. TCP/IP ARCHITECTURE
Network designers often use the seven-layer ISO/OSI (International
Standards Organization/Open Systems Interconnect) model when discussing
network architectures.
Each layer in the model corresponds to one level of network
functionality. At the bottom sits the physical layer, which represents the
physical medium through which data travels--in other words, the network
cabling. Above that is the data-link layer, whose services are provided by
network interface cards. The uppermost layer is the application layer, where
application programs that use network services run.
Figure 1 : An OSI Model
13
Figure 2 : Layer by layer representation
14
4.1) FLOWING OF DATA THROUGH EACH LAYER
As a unit of data flows downward from a network application to the
network interface card, it travels through a succession of TCP/IP modules. At
each step along the way, it is packaged with information required by the
equivalent TCP/IP module on the other end. By the time the data makes it to the
network card, it's a standard Ethernet frame, assuming the network is an
Ethernet network. The TCP/IP software on the receiving end recreates the
original data for the receiving application by grabbing the Ethernet frame and
passing it upward through the TCP/IP stack.
Figure 3 : An exchange using OSI Model
15
4.2) TRANSMISSION OF DATA IN REAL WORLD
NETWORK
To picture what role TCP/IP plays in real-world networks, consider what
happens when a Web browser uses HTTP (HyperText Transfer Protocol) to
retrieve a page of HTML data from a Web server attached to the Internet. The
browser uses a high-level software abstraction called a socket to form a virtual
connection to a server. To retrieve a Web page, it sends an HTTP GET
command to the server by writing the command to the socket. The socket
software in turn uses TCP to send the bits and bytes comprising the GET
command to the Web server. TCP segments the data and passes the individual
segments to the IP module, which transmits the segments in datagrams to the
Web server.
If the browser and the server are running on computers connected to
different physical networks (as is usually the case), the datagrams go from
network to network until they reach the one to which the server is physically
connected. Ultimately, the datagrams are delivered to their destination and
reassembled so that the Web server, which reads chunks of data by performing
reads on its socket, sees a continuous stream of data. To the browser and the
server, data written to the socket at one end shows up at the other end, as if by
magic. But underneath, all sorts of complex interactions have taken p lace to
create an illusion of seamless data transfer across networks.
And that's what TCP/IP is all about: turning lots of small networks into
one big one and providing the services that applications need to communicate
with each other over the resulting Internet.
16
5. GUIDE TO TCP/IP PROTOCOLS AND
ACRONYMS
1) ARP (Address Resolution Protocol): Converts 32-bit IP addresses into
physical network addresses--for example, 48-bit Ethernet addresses.
2) FTP (File Transfer Protocol): Permits files to be transferred from one
computer to another using a TCP connection. A related but less common
file-transfer protocol, Trivial File Transfer Protocol (TFTP), uses UDP
rather than TCP to transfer file data.
3) ICMP (Internet Control Message Protocol): Allows IP routers to send
error and control messages to other IP routers and hosts. ICMP messages
travel in the data fields of IP datagrams and are a required part of all IP
implementations.
4) IGMP (Internet Group Management Protocol): Permits IP datagrams
to be broadcast, or multicast, to computers that belong to multicast
groups.
5) IP (Internet Protocol): A low-level protocol that routes packets of data
across separate networks tied together by routers to form the Internet or
an intranet. Data travels in packets called IP datagrams.
6) RARP (Reverse Address Resolution Protocol): Converts physical
network addresses into IP addresses.
7) SMTP (Simple Mail Transfer Protocol): Specifies the format of
messages that an SMTP client on one computer can use to send electronic
mail to an SMTP server on another computer.
17
8)TCP (Transmission Control Protocol): A connection-oriented protocol
that transmits data in byte streams. Data is transmitted in packets called
TCP segments, which contain TCP headers and data. TCP is a "reliable"
protocol because it uses checksums to verify data integrity and
handshaking to make sure transmitted data is received intact.
9) UDP (User Datagram Protocol): A connectionless protocol that
transmits data in packets called UDP datagrams. UDP is an "unreliable"
protocol because the sender receives no information indicating whether a
datagram was actually received.
18
6. CONCLUSION
There's much more that could be said about TCP/IP, but here are
three key points:
 TCP/IP is a set of protocols that permit physical networks to be joined
together to form an internet. TCP/IP combines the individual networks to
form a virtual network in which individual hosts are identified not by
physical network addresses but by IP addresses.
 TCP/IP uses a multilayered architecture that clearly defines each
protocol's responsibilities. TCP and UDP provide high -level data
transmission services to network application programs, and both rely on
IP to transmit packets of data. IP is responsible for routing the packets to
their destination.
 Data moving between two applications running on Internet hosts travels
up and down the hosts' TCP/IP stacks. Information added by the TCP/IP
modules on the sending end is stripped off by the corresponding TCP/IP
modules on the receiving end and used to re -create the original data.
19
7. BIBLIOGRAPHY
1) Daniel C. Lynch and Marshall T. Rose, Internet System Handbook, Addison
Wesley, pp. 4-14.
2) Daniel C. Lynch and Marshall T. Rose, Internet System Handbook, Addison
Wesley, pp. 80-118.
3) W. Richard Stevens, TCP/IP Illustrated, Volume I: The Protocols, Addison
Wesley, pp. 224.
4) W. Richard Stevens, TCP/IP Illustrated, Volume I: The Protocols, Addison
Wesley, pp. 137-141.
5) www.wikipedia.com

More Related Content

PDF
IP ADDRESSING AND SUBNETTING REPORT
PPTX
Ip spoofing ppt
PPTX
Internet of Things: state of the art
PPTX
Application Layer and Protocols
PPTX
Transport layer protocol
PPTX
Unicast multicast & broadcast
PDF
Network traffic analysis course
PPTX
IP Spoofing
IP ADDRESSING AND SUBNETTING REPORT
Ip spoofing ppt
Internet of Things: state of the art
Application Layer and Protocols
Transport layer protocol
Unicast multicast & broadcast
Network traffic analysis course
IP Spoofing

What's hot (20)

PPTX
ccna networking ppt
PPTX
What Is User Datagram Protocol?
PPT
Lan technologies
PPTX
Man in-the-middle attack(http)
PPTX
IoT Cloud architecture
PDF
PPTX
Transport layer protocols : TCP and UDP
PPTX
BASIC TO ADVANCED NETWORKING TUTORIALS
PPTX
TCP and UDP
PPSX
Parasitic computing
PPTX
Ip Spoofing
PPSX
TCP-IP Reference Model
PDF
REPORT ON ASP.NET
PPTX
Routers.ppt
PPTX
Network and Protocol
PPTX
20 common port numbers and their purposes
PDF
VPN - Virtual Private Network
PDF
3. OSPFv3 Redes IPv6
PPTX
Network (Hub,switches)
PPTX
Ip Spoofing
ccna networking ppt
What Is User Datagram Protocol?
Lan technologies
Man in-the-middle attack(http)
IoT Cloud architecture
Transport layer protocols : TCP and UDP
BASIC TO ADVANCED NETWORKING TUTORIALS
TCP and UDP
Parasitic computing
Ip Spoofing
TCP-IP Reference Model
REPORT ON ASP.NET
Routers.ppt
Network and Protocol
20 common port numbers and their purposes
VPN - Virtual Private Network
3. OSPFv3 Redes IPv6
Network (Hub,switches)
Ip Spoofing
Ad

Viewers also liked (20)

DOCX
Report of TCP/IP
PPT
TCP/IP Network ppt
PDF
Config Guide Ip Sec
PPTX
Seminar
PPT
Web accessibility developers by Bao AN - eXo SEA
PPSX
Cumple2011
PDF
Drink The Water English
PPT
Mcf presentation by Hai NGUYEN-Portal team
PPS
Berntsen -chicago_my_home_town_-_08-10-11
PPS
Seasons Of Life
PPT
Xss.e xopresentation from eXo SEA
PPSX
Cumpleaños
PPSX
Catalog parts
PPTX
Deans workshop
PPTX
Jhonatanlopez
PPS
Coisas antigas 1
PPTX
Barber Library Website Usability Results, Fall 2012
PDF
20140426 wtm66
PPTX
Jhonatanlopez
PPTX
La desicion mas dificil
Report of TCP/IP
TCP/IP Network ppt
Config Guide Ip Sec
Seminar
Web accessibility developers by Bao AN - eXo SEA
Cumple2011
Drink The Water English
Mcf presentation by Hai NGUYEN-Portal team
Berntsen -chicago_my_home_town_-_08-10-11
Seasons Of Life
Xss.e xopresentation from eXo SEA
Cumpleaños
Catalog parts
Deans workshop
Jhonatanlopez
Coisas antigas 1
Barber Library Website Usability Results, Fall 2012
20140426 wtm66
Jhonatanlopez
La desicion mas dificil
Ad

Similar to 53426980 tcp-ip (20)

DOC
Networking-basics
PPTX
TCP/IP Modal
PDF
computer netwrok kjbaskk kjnkjc kjkx .pdf
PDF
TCPIP Model Presentation in Blue Clean Style.pdf
PPTX
L05 _TCP_IP.pptx computer networks TCP IP
PDF
HNS L III UC2 Installing and Managing Network Protocols .pdf
PDF
Unit 3 Assignment 1 Osi Model
PPTX
Lab 4 presentation slide
PPTX
linux unit 4 (2).pptxjiy8t7r7iguyguyy888
PPT
"Internet Protocol Suite" prepared by Szymon M. from Poland
PPTX
Internet1
PPTX
CSS (KNC-301) 2. TCP IP By Vivek Tripathi.pptx
PPTX
2010fall ch6 uugantsetseg
PDF
TCP Vs UDP
PDF
OSPF (Open Shortest Path First) Case Study: Anil Nembang
PPT
OSI model (7 LAYER )
PPTX
ETE405-lec7.pptx
PPTX
TCP/IP-Protocol Suite-Simple Explanation
DOCX
TCP/IP Protocal Suite
DOCX
Chapter 3
Networking-basics
TCP/IP Modal
computer netwrok kjbaskk kjnkjc kjkx .pdf
TCPIP Model Presentation in Blue Clean Style.pdf
L05 _TCP_IP.pptx computer networks TCP IP
HNS L III UC2 Installing and Managing Network Protocols .pdf
Unit 3 Assignment 1 Osi Model
Lab 4 presentation slide
linux unit 4 (2).pptxjiy8t7r7iguyguyy888
"Internet Protocol Suite" prepared by Szymon M. from Poland
Internet1
CSS (KNC-301) 2. TCP IP By Vivek Tripathi.pptx
2010fall ch6 uugantsetseg
TCP Vs UDP
OSPF (Open Shortest Path First) Case Study: Anil Nembang
OSI model (7 LAYER )
ETE405-lec7.pptx
TCP/IP-Protocol Suite-Simple Explanation
TCP/IP Protocal Suite
Chapter 3

Recently uploaded (20)

PDF
Zenith AI: Advanced Artificial Intelligence
PPTX
Chapter 5: Probability Theory and Statistics
PDF
ENT215_Completing-a-large-scale-migration-and-modernization-with-AWS.pdf
PDF
Enhancing emotion recognition model for a student engagement use case through...
PDF
Architecture types and enterprise applications.pdf
PDF
Profit Center Accounting in SAP S/4HANA, S4F28 Col11
PDF
1 - Historical Antecedents, Social Consideration.pdf
PPTX
The various Industrial Revolutions .pptx
PPTX
TechTalks-8-2019-Service-Management-ITIL-Refresh-ITIL-4-Framework-Supports-Ou...
PDF
Getting started with AI Agents and Multi-Agent Systems
PPTX
OMC Textile Division Presentation 2021.pptx
PPTX
MicrosoftCybserSecurityReferenceArchitecture-April-2025.pptx
PPTX
observCloud-Native Containerability and monitoring.pptx
PDF
TrustArc Webinar - Click, Consent, Trust: Winning the Privacy Game
PDF
Transform Your ITIL® 4 & ITSM Strategy with AI in 2025.pdf
PDF
A contest of sentiment analysis: k-nearest neighbor versus neural network
PPTX
Group 1 Presentation -Planning and Decision Making .pptx
PDF
DP Operators-handbook-extract for the Mautical Institute
PDF
Developing a website for English-speaking practice to English as a foreign la...
PPTX
TLE Review Electricity (Electricity).pptx
Zenith AI: Advanced Artificial Intelligence
Chapter 5: Probability Theory and Statistics
ENT215_Completing-a-large-scale-migration-and-modernization-with-AWS.pdf
Enhancing emotion recognition model for a student engagement use case through...
Architecture types and enterprise applications.pdf
Profit Center Accounting in SAP S/4HANA, S4F28 Col11
1 - Historical Antecedents, Social Consideration.pdf
The various Industrial Revolutions .pptx
TechTalks-8-2019-Service-Management-ITIL-Refresh-ITIL-4-Framework-Supports-Ou...
Getting started with AI Agents and Multi-Agent Systems
OMC Textile Division Presentation 2021.pptx
MicrosoftCybserSecurityReferenceArchitecture-April-2025.pptx
observCloud-Native Containerability and monitoring.pptx
TrustArc Webinar - Click, Consent, Trust: Winning the Privacy Game
Transform Your ITIL® 4 & ITSM Strategy with AI in 2025.pdf
A contest of sentiment analysis: k-nearest neighbor versus neural network
Group 1 Presentation -Planning and Decision Making .pptx
DP Operators-handbook-extract for the Mautical Institute
Developing a website for English-speaking practice to English as a foreign la...
TLE Review Electricity (Electricity).pptx

53426980 tcp-ip

  • 1. A Seminar Report On TCP-IP Submitted to The Rajasthan Technical University In partial fulfillment of the requirements of the Award of the Degree Of Bachelor Of Technology (Information Technology) KAUTILYA INSITUTE OF TECHNOLOGY AND ENGINEERING JAIPUR Submitted to: Submitted By: Mr. Chetan Kumar Ayush Bilala (Dept. Head) Roll No. 07EKTIT013 B-Tech 4th Year,8th Sem Department Of Information Technology Kautilya Institute Of Technology And Engineering Affiliated To Rajasthan Technical University, Kota 2010-2011
  • 2. 2 AACCKKNNOOWWLLEEDDGGMMEENNTT This seminar report could not have been prepared without the help and encouragement from various people. Hence for the same reason I would like to thank my faculties without whom this report would have been a difficult task. It was for support that I got proper guidelines preparing my presentation . I would also like to thank my everyone who helped me directly or indirectly. KRIPASHANKAR SHARMA (07EKTIT013)
  • 3. 3 CCOONNTTEENNTT 01. ABSTRACT««««««««««««««4 02. INTRODUCTION............................................ 5 03. TCP-IP BASICS««««.«««««««.. 6 03.1 Origin of TCP-IP 03.2 TCP-IP and Intranets 03.3 Basic Function of TCP-IP 03.4 User Datagram protocol 03.5 Other important protocols 04. TCP-IP ARCHITECTURE«..««««««12 04.1 Flowing of data through each layer 04.2 Transmission of data in real world n/w 05. ACRONYMS««..«««««««««««16 06. CONCLUSION««««««««««««...18 07. BIBLIOGRAPHY««.««««««««.....19
  • 4. 4 11.. AABBSSTTRRAACCTT One of the most important achievement of last decade is popularity of internet. Today internet has become part of our day to day life.TCP/IP in a broad sense can be explained as the concept on which internet works.The paper attempts to familiarize with some of the basic concepts of TCP/IP. It starts with a brief introduction of TCP/IP and provides the basics of it.It also gives a brief origin of TCP/IP and the basic function of these protocols.It also gives the structure of TCP/IP and explains how transmission of data takes place in real world network.It also gives description of some of the protocols that constitute TCP/IP.The conclusion summarizes the key points of TCP/IP.
  • 5. 5 22.. IINNTTRROODDUUCCTTIIOONN Most of us know of TCP/IP as the glue that binds the Internet. But not as many can offer a cogent description of what it is and how it works. So what is TCP/IP, really? TCP/IP is a means for networked computers to communicate with each other. It doesn't matter whether they are part of the same network or are attached to separate networks. It doesn't matter if one computer is a Cray and the other a Macintosh. TCP/IP is a platform-independent standard that bridges the gap between dissimilar computers, operating systems, and networks. It's the protocol that drives the global Internet, and it is to the Internet that TCP/IP owes much of its popularity. Understanding TCP/IP is largely a matter of understanding a collection of arcane protocols that TCP/IP hosts use to exchange information. Let's look at some of those protocols and see what makes TCP/IP tick .
  • 6. 6 33.. TTCCPP--IIPP BBAASSIICCSS TCP/IP stands for Transmission Control Protocol/Internet Protocol. In networking terms, a protocol is an agreed-upon standard that permits two computers to exchange data. TCP/IP isn't just one protocol, but several. That's why you'll often hear it referred to as a protocol suite, of which TCP and IP are the two principal protocols. The TCP/IP software that you install on a computer provides platform- specific implementations of TCP, IP, and other members of the TCP/IP family. Typically, it also includes high-level application programs, such as FTP (File Transfer Protocol), which permits users to perform network file transfers from the command line.
  • 7. 7 3.1) ORIGIN OF TCP/IP TCP/IP is an outgrowth of research funded by the U.S. government's Advanced Research Projects Agency (ARPA) in the 1970s. It was developed so that research networks around the world could be joined to form a virtual network known as an internetwork. The original Internet was formed by converting an existing conglomeration of networks, known as ARPAnet, over to TCP/IP; that Internet would eventually become the backbone of today's Internet.
  • 8. 8 3.2) TCP/IP AND INTRANETS The reason TCP/IP is so important today is that it allows standalone networks to be connected to the Internet or linked together to create private intranets. The networks that comprise an intranet are physically connected by devices called routers or IP routers. A router is a computer that transfers packets of data from one network to another. On a TCP/IP intranet, information travels in discrete units called IP packets or IP datagrams. TCP/IP software makes each computer attached to the network a sibling t o all the others; in essence, it hides the routers and underlying network architectures and makes everything seem like one big network. Just as connections to an Ethernet network are identified by 48-bit Ethernet IDs, connections to an intranet are identified by 32-bit IP addresses, which we express as dotted decimal numbers (for example, 128.10.2.3). Given a remote computer's IP address, a computer on an intranet or the Internet can send data to the remote computer as if the two were part of the same physical network.
  • 9. 9 3.3) BASIC FUNCTION OF TCP AND IP TCP/IP provides a solution to the problem of how two computers attached to the same intranet but belonging to different physical networks can exchange data. The solution comes in several parts, with each member of the TCP/IP protocol suite filling in one piece of the puzzle. The most fundamental TCP/IP protocol, IP, transmits IP datagrams across an intranet and performs an important function called routing--choosing the path that datagrams will follow to get from A to B and using routers to "hop" networks. TCP is a higher-level protocol that allows applications running on different hosts to exchange data streams. TCP divides data streams into chunks called TCP segments and transmits them using IP. In most cases, each TCP segment is sent in a single IP datagram. If necessary, however, TCP will split segments into multiple IP datagrams that are compatible with the physical data frames that carry bits and bytes between hosts on a network. Because IP doesn't guarantee that datagrams will be received in the same order in which they were sent, TCP reassembles TCP segments at the other end to form an uninterrupted data stream. FTP and telnet are two examples of popular TCP/IP applications that rely on TCP.
  • 10. 10 3.4 USER DATAGRAM PROTOCOL Another important member of the TCP/IP suite is the User Datagram Protocol (UDP), which is similar to but more primitive than TCP. TCP is a "reliable" protocol because it performs the error-checking and handshaking necessary to verify that data makes it to its destination intact. UDP is an "unreliable" protocol because it doesn't guarantee that datagrams will arrive in the order in which they were sent or even that they will arrive at all. If reliability is desired, it's up to the application to provide it. Still, UDP has its place in the TCP/IP universe, and a number of applications use it. The SNMP (Simple Network Management Protocol) application provided with most implementations of TCP/IP is one example of a UDP application.
  • 11. 11 3.5) OTHER IMPORTANT PROTOCOLS OF TCP/IP : Other TCP/IP protocols play less visible but equally important roles in the operation of TCP/IP networks. For example, the Address Resolution Protocol (ARP) translates IP addresses into physical network addresses, such as Ethernet IDs. A related protocol, the Reverse Address Resolution Protocol (RARP), does the opposite, converting physical network addresses into IP addresses. The Internet Control Message Protocol (ICMP) is a support protocol that uses IP to communicate control and error information regarding IP packet transmissions. If a router is unable to forward an IP datagram, for example, it uses ICMP to inform the sender that there's a problem. For a summary of some of the other protocols that fall under the TCP/IP umbrella, see the sidebar above.
  • 12. 12 4. 4. TCP/IP ARCHITECTURE Network designers often use the seven-layer ISO/OSI (International Standards Organization/Open Systems Interconnect) model when discussing network architectures. Each layer in the model corresponds to one level of network functionality. At the bottom sits the physical layer, which represents the physical medium through which data travels--in other words, the network cabling. Above that is the data-link layer, whose services are provided by network interface cards. The uppermost layer is the application layer, where application programs that use network services run. Figure 1 : An OSI Model
  • 13. 13 Figure 2 : Layer by layer representation
  • 14. 14 4.1) FLOWING OF DATA THROUGH EACH LAYER As a unit of data flows downward from a network application to the network interface card, it travels through a succession of TCP/IP modules. At each step along the way, it is packaged with information required by the equivalent TCP/IP module on the other end. By the time the data makes it to the network card, it's a standard Ethernet frame, assuming the network is an Ethernet network. The TCP/IP software on the receiving end recreates the original data for the receiving application by grabbing the Ethernet frame and passing it upward through the TCP/IP stack. Figure 3 : An exchange using OSI Model
  • 15. 15 4.2) TRANSMISSION OF DATA IN REAL WORLD NETWORK To picture what role TCP/IP plays in real-world networks, consider what happens when a Web browser uses HTTP (HyperText Transfer Protocol) to retrieve a page of HTML data from a Web server attached to the Internet. The browser uses a high-level software abstraction called a socket to form a virtual connection to a server. To retrieve a Web page, it sends an HTTP GET command to the server by writing the command to the socket. The socket software in turn uses TCP to send the bits and bytes comprising the GET command to the Web server. TCP segments the data and passes the individual segments to the IP module, which transmits the segments in datagrams to the Web server. If the browser and the server are running on computers connected to different physical networks (as is usually the case), the datagrams go from network to network until they reach the one to which the server is physically connected. Ultimately, the datagrams are delivered to their destination and reassembled so that the Web server, which reads chunks of data by performing reads on its socket, sees a continuous stream of data. To the browser and the server, data written to the socket at one end shows up at the other end, as if by magic. But underneath, all sorts of complex interactions have taken p lace to create an illusion of seamless data transfer across networks. And that's what TCP/IP is all about: turning lots of small networks into one big one and providing the services that applications need to communicate with each other over the resulting Internet.
  • 16. 16 5. GUIDE TO TCP/IP PROTOCOLS AND ACRONYMS 1) ARP (Address Resolution Protocol): Converts 32-bit IP addresses into physical network addresses--for example, 48-bit Ethernet addresses. 2) FTP (File Transfer Protocol): Permits files to be transferred from one computer to another using a TCP connection. A related but less common file-transfer protocol, Trivial File Transfer Protocol (TFTP), uses UDP rather than TCP to transfer file data. 3) ICMP (Internet Control Message Protocol): Allows IP routers to send error and control messages to other IP routers and hosts. ICMP messages travel in the data fields of IP datagrams and are a required part of all IP implementations. 4) IGMP (Internet Group Management Protocol): Permits IP datagrams to be broadcast, or multicast, to computers that belong to multicast groups. 5) IP (Internet Protocol): A low-level protocol that routes packets of data across separate networks tied together by routers to form the Internet or an intranet. Data travels in packets called IP datagrams. 6) RARP (Reverse Address Resolution Protocol): Converts physical network addresses into IP addresses. 7) SMTP (Simple Mail Transfer Protocol): Specifies the format of messages that an SMTP client on one computer can use to send electronic mail to an SMTP server on another computer.
  • 17. 17 8)TCP (Transmission Control Protocol): A connection-oriented protocol that transmits data in byte streams. Data is transmitted in packets called TCP segments, which contain TCP headers and data. TCP is a "reliable" protocol because it uses checksums to verify data integrity and handshaking to make sure transmitted data is received intact. 9) UDP (User Datagram Protocol): A connectionless protocol that transmits data in packets called UDP datagrams. UDP is an "unreliable" protocol because the sender receives no information indicating whether a datagram was actually received.
  • 18. 18 6. CONCLUSION There's much more that could be said about TCP/IP, but here are three key points: TCP/IP is a set of protocols that permit physical networks to be joined together to form an internet. TCP/IP combines the individual networks to form a virtual network in which individual hosts are identified not by physical network addresses but by IP addresses. TCP/IP uses a multilayered architecture that clearly defines each protocol's responsibilities. TCP and UDP provide high -level data transmission services to network application programs, and both rely on IP to transmit packets of data. IP is responsible for routing the packets to their destination. Data moving between two applications running on Internet hosts travels up and down the hosts' TCP/IP stacks. Information added by the TCP/IP modules on the sending end is stripped off by the corresponding TCP/IP modules on the receiving end and used to re -create the original data.
  • 19. 19 7. BIBLIOGRAPHY 1) Daniel C. Lynch and Marshall T. Rose, Internet System Handbook, Addison Wesley, pp. 4-14. 2) Daniel C. Lynch and Marshall T. Rose, Internet System Handbook, Addison Wesley, pp. 80-118. 3) W. Richard Stevens, TCP/IP Illustrated, Volume I: The Protocols, Addison Wesley, pp. 224. 4) W. Richard Stevens, TCP/IP Illustrated, Volume I: The Protocols, Addison Wesley, pp. 137-141. 5) www.wikipedia.com