Data Communications and IP Calculation

Running head: DATA COMMUNICATIONS AND IP CALCULATION
Data Communications and IP Calculation
Student Name
University Name
Note by the author

1DATA COMMUNICATIONS AND IP CALCULATION
Question 1: Different layers of OSI model and their roles
Functions of OSI layers
The seven layers of the OSI reference model each perform specific set of functions.
Physical layer, the first layer of OSI is responsible for conveying a bit stream of light signal
and electric impulse. Data can be send and received by means of hardware which can include
network cards, motherboard sections and cables. Protocols associated with these components
of the physical layer can be RS232, fast Ethernet and ATM. OSI model’s second layer is the
data link layer which involves encoding and decoding of data packets takes place (Zhao et al.,
2018). It is also used in furnishing knowledge of transmission protocol and handling errors
surrounding physical layer. The network layer or third layer of OSI model is responsible for
providing routing and switching mechanisms through virtual circuits that are used to transfer
data packets from node to node. The transport layer or fourth layer of this model ensures
complete transfer of data between hosts and end system. The session layer or fifth layer of
OSI terminates, establishes and manages connections among the applications. The
presentation layer or sixth layer, helps in convert data into forms, which is understandable for
the application layer. The application layer or seventh layer supports the application
processes and the end-users processes (Alotaibi et al., 2017). Service quality, communication
pattern, data syntax constraints are identified and privacy and authentication of user are
considered.
The application, session and presentation layer are the software layer whereas
network, physical and data link layers are the hardware layers. Transport layer, heart of the
OSI model separates the software and hardware layers.
The internet layer perform the function of packet switching networking that is based
on the connectionless network layer. This layer is responsible for holding the whole

2DATA COMMUNICATIONS AND IP CALCULATION
architecture of the model. This help in free moving of the packets over the internet. The order
of receiving and sending the packets are different. This layer uses Internet Protocol. Whereas
the network layer allow the interconnection of different networks. The networking layer of
the OSI model is compared to the TCP/IP model. The network layer routes the data from
node to node and the internet layer transfer the data packets and provides routing facility over
the internet (Goralski, 2017). Both these layers are engaged in transferring data packets but
internet layer transfer it over internet so it called as internet layer in the TCP/IP model.

3DATA COMMUNICATIONS AND IP CALCULATION
Question 2: IP Subneet Calculation
Hands-On Project 2.3
1. & 2. Enter the addresss www.gestioip.net/cgi-bin/subnet_calculator.cgi and in the web
page that opens please check that ipv4 radio button is chosen.
3. In the IP address field give the IP 192.168.0.0 as input