Network Layer

This document provides an overview of the network layer, including the OSI layered architecture, a comparison of the OSI reference model with the TCP/IP protocol, common applications found in the TCP/IP protocol suite, another network model besides OSI and TCP/IP, and an analysis of wired and wireless mediums in terms of cost, speed, expandability, distance, environment, and security.

NETWORK LAYER

TABLE OF CONTENTS
OSI layered architecture with a suitable diagram............................................................................1
Comparison of OSI reference model with the TCP/IP protocol......................................................2
Some common applications found in the TCP/IP protocol suite.....................................................2
One other network model which exist besides the OSI model and TCP/IP Protocol suite.............2
Analyse wired and wireless mediums with suitable examples in terms of cost, speed,
expandability & distance, environment, and security......................................................................3
REREFENCES................................................................................................................................5

OSI layered architecture with a suitable diagram
OSI or open system interconnection model is a kind of model that helps in explaining
functions of networking system. It helps in maintaining communication within different
computer systems. It has seven different abstraction layer: physical, data link, network, transport,
session, presentation and application layer. Each of these layers has its own functions that has
been explained below:
Physical layer: Main function of this layer is to sent or transmits raw and unstructured data bits
from physical layer of sending device to Physical layer of receiving device (Sinha and et. al.,
2017).
Data link layer: At this layer node to node data is transferred where data is packed into frames.
Any kind of error that has occurred at physical layer is also corrected at this layer.
Network layer: It is mainly responsible for receiving frames from previous layer and deliver
them to their intended destination. On the basis of address contained within the frames.
Transport layer: Main function of this layer is to manage delivery and error checking of data
frames.
Session layer: It majorly controls conversation between different systems.
Presentation layer: It translates data for application layer on the basis of syntax that are accepted
by application.
Application layer: At this layer both user and layer interacts with end software application.
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Comparison of OSI reference model with the TCP/IP protocol
There are various kinds of differences between OSI reference model and TCP/IP protocol
model, Some of the main differences between both the models are as follows:
 OSI reference model has seven layers whereas TCP/IP protocol has only four layers that are:
network interface, network, transport and application (Aggarwal, Gupta and Saxena, 2019).
 OSI is a conceptual and logical model that helps in defining network communication
between systems for communication with other systems. Whereas, TCP/IP focuses upon
defining ways in which computer should be connected to internet and ways in which data can
be transmitted between them.
 Header of OSI model is of 5 bits whereas header of TCP/IP is of 20 bits.
 In OSI model transport layer is only connection oriented whereas in TCP/IP is both
connection oriented and connectionless.
Some common applications found in the TCP/IP protocol suite
There are many different kinds of applications that are found within TCP/IP protocol
suite some of them are: web browsing, e-mail, file transfer, remote logins, FTP and many more.
One other network model which exist besides the OSI model and TCP/IP
Protocol suite
Other kinds of network model that exist besides OSI model and TCP/IP network model
is: Cisco 3- layer hierarchical model. The main purpose of this model is to provide fault isolation
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and backbone connectivity. This model consists of three main layers: core layer, access layer and
network layer.
 Core layer: this layer is the backbone of this network model. It is one of the most important
and critical layers because the main purpose of this layer is to provide connectivity and fault
isolation. It also helps in switching traffic at higher speed (Kurniawan and et. al., 2016).
 Network layer: it is also known as distribution layer which is used as a communication point
between access layer and core layer. It helps in handling routing, WAN access, packet
filtering and determine ways in which packet can reach the core.
 Access layer: it is also known as desktop layer that focuses upon collecting client devices
such as: laptops, servers, workstations etc.
Analyse wired and wireless mediums with suitable examples in terms of cost,
speed, expandability & distance, environment, and security
Analysis of wired network medium:
Wired medium is a medium which is described as a configuration that involves, cables
for establishment of connection with internet and other devices.
 Cost: As per the framework of wired network it is a bit inexpensive to install. Ethernet
cables, switches, routers etc. are a bit inexpensive to install.
 Speed: wired medium are much faster than wireless medium. Advancement in technology
has increased speed of network up to gigabytes with the help of gigabyte routers.
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 Security: When it is configured with required and important firewalls and other security
applications, it helps in protecting system from unauthorised access and also helps in
monitoring suspicious activities.
 Expandability and distance: Wired connection generally reliable. But they can cover only a
limited distance and cannot be expanded more then a certain distance.
Analysis of wireless network medium:
 Cost: Unit ill and unless there is no need to install additional network equipment’s like
wireless repeaters or a commercial grade router it is a bit inexpensive.
 Speed: Speed of wireless network medium is good but a bit less then wired medium.
 Security: Wireless medium is less secure then wired medium. In order to increase security of
the network there is requirement to provides a more reliable connection and improved
security controls.
 Expandability and distance: Devices can be accessed from any location by using any type of
wireless enabled devices.
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REREFENCES
Books and Journals
Aggarwal, N., Gupta, R. and Saxena, P., 2019. Comparative Study of OSI & TCP/IP Reference
Model. International Journal for Research in Applied Science & Engineering
Technology (IJRASET).
Kurniawan, M.T., and et. al., 2016. Desain Topologi Jaringan Kabel Nirkabel PDII-LIPI dengan
Cisco Three-Layered Hierarchical menggunakan NDLC. ELKOMIKA: Jurnal Teknik
Energi Elektrik, Teknik Telekomunikasi, & Teknik Elektronik. 4(1). p.47.
Sinha, P., and et. al., 2017, July. Security vulnerabilities, attacks and countermeasures in wireless
sensor networks at various layers of OSI reference model: A survey. In 2017
International Conference on Signal Processing and Communication (ICSPC) (pp. 288-
293). IEEE.
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