1. Assignment
On
Class Lecture-03
Course code : CSE – 313
Course name : Data communication
Submitted to
Pronab Bandhu Nath
Senior Lecturer
Department of CSE
City university
Submitted by
Name : Rowshanara
ID : 1834902165
Batch : 49th
(B)
Department of CSE
Submission date : 24/08/2021
2. OSI model : OSI stands for Open System
Interconnection. There are 7 layers in the OSI model and
each layer has a different capability.
Work of OSI model : The OSI reference model
describes how data is sent and received over a network.
This model breaks down data transmission over a series of
seven layers. Each layer has a responsibility to perform
specific tasks concerning sending and receiving data. All of
the layers are needed for a message to reach its destination.
i
The 7 layer’s of the OSI model :
1.Physical layer.
2.Data link layer.
3.Network layer.
4.Transport layer.
5.Session layer.
6.Presentation layer.
7.Application layer.
Physical layer : In this layer transmit bit's over a medium
and identify NIC.
3. Data link : In this layer organized bits into frame to provide
hop- to – hop delivery and identify the MAC address.
Network layer : In this layer the packets moves form
source to destination to provide internetworking.
Transport layer : This layer provide reliable process to
process message delivery and error delivery.
Session layer : The session layer controls the
conversations between different computers. Session layer
services also include authentication and reconnections.
Presentation layer : This layer translate, encrypt and
compress data.
Application layer : This layer provide allow access to
network recourses.
TCP /IP model : It stands for Transmission Control
Protocol/Internet Protocol. The TCP/IP model is a concise
version of the OSI model. It contains four layers, unlike seven
layers in the OSI model.
4. The 4 layer of TCP/IP model:
1.Application layer.
2.Transport layer.
3. Internet layer.
4.Network interface layer.
