( College Logo )

Programme Name and Code: CO3I Academic Year : 2018-2019

Course Name and Code: Data Communication and Computer Network

Semester : Fourth

A STUDY ON

TCP/ISO Model / and IP Reference

MICRO PROJECT REPORTSubmitted in (date) by the group of (no of group members) students

Sr. No

Roll No(Sem-IV)

Full name of Student Enrollment No

Seat No (Sem-

IV)123

Under the Guidance of

Prof. ( your guide name )

In

Three Years Diploma Programme in Engineering & Technology of Maharashtra State Board of Technical Education, Mumbai (Autonomous)

ISO 9001:2008 (ISO/IEC-27001:2013)

At

( your college name )

1

MAHARASHTRA STATE BOARD OF TECHNICAL EDUCATION, MUMBAI

CertificateThis is to certify that Mr. / Ms.

Roll No: of Second Semester of Diploma

Programme in Engineering & Technology at ( your college name ) , has completed

the Micro Project satisfactorily in Subject Data Communication and Computer

Network ( ) in the academic year 2018-2019 as per the MSBTE prescribed curriculum

of I Scheme.

Place: Pune Enrollment No:

Date : / / 2018 Exam. Seat No:

Project Guide Head of the Department Principal

2

Seal of Institute

Index…

Sr. No Title Page No

Abstract

1 Introduction 5

2 Literature Survey 6

3. How TCP/IP works 7

4. Layers In TCP/IP Model 7-8

5. OSI Model 9

6. Layers In OSI Model 9-13

7. Diff. between OSI and TCP/IP 14

8. IP Reference 15

9. Conclusion 16

10. References 17

11. Weekly Work / Progress Report 18

12. Evaluation Sheet 19

3

Abstract

A networking model offers a generic means to separate computer networking functions into multiple layers.

Each of these layers relies on the layers below it to provide supporting capabilities and performs support to

the layers above it. Such a model of layered functionality is also called a “protocol stack” or “protocol suite”.

Protocols, or rules, can do their work in either hardware or software or, as with most protocol stacks, in a

com- bination of the two. The nature of these stacks is that the lower layers do their work in hardware or

firmware

4

INTRODUCTION

The entire internet protocol suite a set of rules and procedures -- is commonly referred to as TCP/IP, though

others are included in the suite.

TCP/IP specifies how data is exchanged over the internet by providing end-to-end communications that

identify how it should be broken into packets, addressed, transmitted, routed and received at the destination.

TCP/IP requires little central management, and it is designed to make networks reliable, with the ability to

recover automatically from the failure of any device on the network.

The two main protocols in the internet protocol suite serve specific functions. TCP defines how applications

can create channels of communication across a network. It also manages how a message is assembled into

smaller packets before they are then transmitted over the internet and reassembled in the right order at the

destination address.

IP defines how to address and route each packet to make sure it reaches the right destination.

Each gateway computer on the network checks this IP address to determine where to forward the message.

5

LITERATURE SURVEY

Title of the book

Author Publication

Computer Networks: A Top - Down Approach

Behrouz A Forouzan

Firouz Mosharraf

Mc Graw Hill

An Introduction to Computer Networks

Peter L Dordal

The Saylor Foundation

Computer Networking : Principles, Protocols and Practice

Olivier Bonaventure

The Saylor Foundation

Data Communication and Computer Network

Godbole Kahate

Mc Graw Hill

The Complete Reference Networking

Zacker Mc Graw Hill

6

How TCP/IP works

TCP/IP uses the client/server model of communication in which a user or machine (a client) is provided a service (like sending a webpage) by another computer (a server) in the network.

Collectively, the TCP/IP suite of protocols is classified as stateless, which means each client request is considered new because it is unrelated to previous requests. Being stateless frees up network paths so they can be used continuously.

The transport layer itself, however, is stateful. It transmits a single message, and its connection remains in place until all the packets in a message have been received and reassembled at the destination.

The TCP/IP model differs slightly from the seven-layer Open Systems Interconnection (OSI) networking model designed after it, which defines how applications can communicate over a network.

TCP/IP model layers.

TCP/IP functionality is divided into four layers, each of which include specific protocols.

7

The application layer provides applications with standardized data exchange. Its protocols include the Hypertext Transfer Protocol (HTTP), File Transfer Protocol (FTP), Post Office Protocol 3 (POP3), Simple Mail Transfer Protocol (SMTP) and Simple Network Management Protocol (SNMP).

The transport layer is responsible for maintaining end-to-end communications across the network. TCP handles communications between hosts and provides flow control, multiplexing and reliability. The transport protocols include TCP and User Datagram Protocol (UDP), which is sometimes used instead of TCP for special purposes.

The network layer, also called the internet layer, deals with packets and connects independent networks to transport the packets across network boundaries. The network layer protocols are the IP and the Internet Control Message Protocol (ICMP), which is used for error reporting.

The physical layer consists of protocols that operate only on a link -- the network component that interconnects nodes or hosts in the network. The protocols in this layer

8

include Ethernet for local area networks (LANs) and the Address Resolution Protocol (ARP).

Advantages of TCP/IP

TCP/IP is nonproprietary and, as a result, is not controlled by any single company. Therefore, the internet protocol suite can be modified easily. It is compatible with all operating systems, so it can communicate with any other system. The internet protocol suite is also compatible with all types of computer hardware and networks.

OSI model

The Open Systems Interconnection model (OSI model) is a conceptual model that characterizes and standardizes the communication functions of a telecommunication or computing system without regard to its underlying internal structure and technology.

Its goal is the interoperability of diverse communication systems with standard protocols. The model partitions a communication system into abstraction layers. The original version of the model defined seven layers.A layer serves the layer above it and is served by the layer below it. For example, a layer that provides error-free communications across a network provides the path needed by applications above it, while it calls the next lower layer to send and receive packets that comprise the contents of that path.

9

Data processing by two communicating OSI-compatible devices is done as such:

1. The data to be transmitted is composed at the topmost layer of the transmitting device (layer N) into a protocol data unit (PDU).

2. The PDU is passed to layer N-1, where it is known as the service data unit (SDU).3. At layer N-1 the SDU is concatenated with a header, a footer, or both, producing a layer

N-1 PDU. It is then passed to layer N-2.4. The process continues until reaching the lowermost level, from which the data is

transmitted to the receiving device.5. At the receiving device the data is passed from the lowest to the highest layer as a series

of SDUs while being successively stripped from each layer's header or footer, until reaching the topmost layer, where the last of the data is consumed.

10

Some orthogonal aspects, such as management and security, involve all of the layers (See ITU-T X.800 Recommendation). These services are aimed at improving the CIA triad - confidentiality, integrity, and availability - of the transmitted data.

In practice, the availability of a communication service is determined by the interaction between network design and network management protocols. Appropriate choices for both of these are needed to protect against denial of service.

Layer 1: Physical Layer The physical layer is responsible for the transmission and reception of unstructured raw data between a device and a physical transmission medium. It converts the digital bits into electrical, radio, or optical signals. Layer specifications define characteristics such as voltage levels, the timing of voltage changes, physical data rates, maximum transmission distances, and physical connectors.

This includes the layout of pins, voltages, line impedance, cable specifications, signal timing and frequency for wireless devices. Bit rate control is done at the physical layer and may define transmission mode as simplex, half duplex, and full duplex. The components of a physical layer can be described in terms of a network topology. Bluetooth, Ethernet, and USB all have specifications for a physical layer.

Layer 2: Data Link Layer The data link layer provides node-to-node data transfer—a link between two directly connected nodes. It detects and possibly corrects errors that may occur in the physical layer. It defines the protocol to establish and terminate a connection between two physically connected devices. It also defines the protocol for flow control between them.IEEE 802 divides the data link layer into two sublayers:

Medium access control (MAC) layer – responsible for controlling how devices in a network gain access to a medium and permission to transmit data.

Logical link control (LLC) layer – responsible for identifying and encapsulating network layer protocols, and controls error checking and frame synchronization.

The MAC and LLC layers of IEEE 802 networks such as 802.3 Ethernet, 802.11 Wi-Fi, and 802.15.4 ZigBee operate at the data link layer.

11

The Point-to-Point Protocol (PPP) is a data link layer protocol that can operate over several different physical layers, such as synchronous and asynchronous serial lines.

The ITU-T G.hn standard, which provides high-speed local area networking over existing wires (power lines, phone lines and coaxial cables), includes a complete data link layer that provides both error correction and flow control by means of a selective-repeat sliding-window protocol.

Layer 3: Network Layer

The network layer provides the functional and procedural means of transferring variable length data sequences (called packets) from one node to another connected in "different networks". A network is a medium to which many nodes can be connected, on which every node has an address and which permits nodes connected to it to transfer messages to other nodes connected to it by merely providing the content of a message and the address of the destination node and letting the network find the way to deliver the message to the destination node, possibly routing it through intermediate nodes.

If the message is too large to be transmitted from one node to another on the data link layer between those nodes, the network may implement message delivery by splitting the message into several fragments at one node, sending the fragments independently, and reassembling the fragments at another node. It may, but does not need to, report delivery errors.

12

Message delivery at the network layer is not necessarily guaranteed to be reliable; a network layer protocol may provide reliable message delivery, but it need not do so.

A number of layer-management protocols, a function defined in the management annex, ISO 7498/4, belong to the network layer. These include routing protocols, multicast group management, network-layer information and error, and network-layer address assignment. It is the function of the payload that makes these belong to the network layer, not the protocol that carries them.

Layer 4: Transport Layer The transport layer provides the functional and procedural means of transferring variable-length data sequences from a source to a destination host, while maintaining the quality of service functions.

The transport layer controls the reliability of a given link through flow control, segmentation/desegmentation, and error control. Some protocols are state- and connection-oriented. This means that the transport layer can keep track of the segments and re-transmit those that fail delivery. The transport layer also provides the acknowledgement of the successful data transmission and sends the next data if no errors occurred.

The transport layer creates segments out of the message received from the application layer. Segmentation is the process of dividing a long message into smaller messages.

13

OSI defines five classes of connection-mode transport protocols ranging from class 0 (which is also known as TP0 and provides the fewest features) to class 4 (TP4, designed for less reliable networks, similar to the Internet). Class 0 contains no error recovery, and was designed for use on network layers that provide error-free connections.

Class 4 is closest to TCP, although TCP contains functions, such as the graceful close, which OSI assigns to the session layer. Also, all OSI TP connection-mode protocol classes provide expedited data and preservation of record boundaries. Detailed characteristics of TP0-4 classes are shown in the following table:

Difference between OSI and TCP/IP

14

IP Reference :15

The Internet protocol suite is the conceptual model and set of communications protocols used in the Internet and similar computer networks. It is commonly known as TCP/IP because the foundational protocols in the suite are the Transmission Control Protocol (TCP) and the Internet Protocol (IP). It is occasionally known as the Department of Defense (DoD) model because the development of the networking method was funded by the United State Department of Defense through DARPA.

The Internet protocol suite provides end-to-end data communication specifying how data should be packetized, addressed, transmitted, routed, and received. This functionality is organized into four abstraction layers, which classify all related protocols according to the scope of networking involved. From lowest to highest, the layers are the link layer, containing communication methods for data that remains within a single network segment (link); the internet layer, providing internetworking between independent networks; the transport layer, handling host-to-host communication; and the application layer providing process-to-process data exchange for applications.

Conclusion 16

Thus, we had studied about Network Models . In this we had seen various types of Network Layers and their advantages and

disadvantages. Thus, we came on conclusion that using Network Layers we can interact and share

files efficiently.

References

17

Websites :

1. https://www.geeksforgeeks.org/2. http://www.tutorialspoint.com/

18