Welcome to the Computer Science and Technology Study Materials section from CoreNetworkZ EdTech Solutions, a leading mock test and competitive exam preparation platform, for students preparing for SSC, DSSSB, and Kerala PSC examinations.
Today, I will explain the first layer and its functions in a network. I will also explain the devices working in the first layer of the OSI Reference Model.
The physical layer is the first layer in the OSI model that deals with the physical transmission medium. The data transferred via the physical layer is in the form of electrical signals.
In real life, we can treat the physical layer as the road where the vehicles are passing. There is a reason why I chose the road to explain the Physical Layer. The road is the one which is carrying the vehicles and linking the cities.
The physical layer is the lowest layer in the OSI Reference Model.
Like that example, the physical layer transmits the data signal in electrical signals and connecting nodes.
We can consider the road as the physical layer and vehicles as the electric signals. Just replace the city with a node. I guess you understand the concept.
How does This Study Material help PSC, SSC, and DSSSB Aspirants?
SSC, DSSSB, and Kerala PSC conduct examinations for various IT posts.
Understanding Physical layer in OSI model is essential for candidates appearing for the DSSSB PGT/TGT Computer Science, Kerala PSC Degree Level Exam, SSC Scientific Assistant (CS), VSSC Technical Assistant, and System Analyst posts. These networking fundamentals are core parts of the Computer Science syllabus.
Kerala PSC Degree Level examinations have a Computer Science section where students can expect questions from the Physical layer in OSI model. You can check the Kerala PSC Degree Level Common Prelims Syllabus under the Computer Science section. I recommend you download the syllabus using this official link.
Reference: https://www.keralapsc.gov.in/sites/default/files/2021-02/syllubus.pdf
The major cables using in physical layer
The physical layer is all about the connections. So, which cables do we use in this layer to form a network?
CoreNetworkZ Tech Solutions has a dedicated team that installs computer networks.
We use the following three types of cables to form a computer network. They create the physical layer of a network.
Coaxial cable
Twisted pair cable
Optical fiber cable
Devices Working in the Physical Layer
Tito Mathew asked about the devices that work in this layer. I recommend everyone to learn it. Sometimes, interviewers may ask about the devices working in the physical layer. They are:
Internet gateway
Hub
Repeater
The Functions and Services Performed by the Physical Layer are:
James Anderson asked me about the functions of the OSI Reference Model's first layer. The functions and responsibilities of the physical layer are:
1. Bit-by-bit delivery
2. Modulation
3. Encoding and Signaling:
4. Bit synchronization
5. Physical Network Topology
In the Physical Layer, data flows in the form of an electric pulse, and the cables are responsible for the safe delivery of the signals. The physical layer is responsible for varying the waveform for the data transfer. This process is known as modulation.
The physical layer is also responsible for various types of encoding and decoding of signals.
The physical layer cares about the transmission mode. It is also the physical layout of the network( topology).
Reference
- https://www.keralapsc.gov.in/sites/default/files/2021-02/syllubus.pdf
- https://www.cisco.com/E-Learning/bulk/guest/celc/fwl/a1/a1_0_0/a1_0_0.pdf
Author: Alex George
Alex George is the Chief Editor and founder of CoreNetworkZ EdTech Solutions. He is a software engineer and has 20 years of experience in the EdTech niche.
He graduated with a B.Tech in Computer Science & Engineering from CUSAT and worked with three leading IT companies before starting CoreNetworkZ EdTech Solutions.
He possesses sound knowledge of SOHO Network Engineering and has completed various IT certifications, including CCNA, RHCE, and CEH.
He developed and published more than twenty professional custom themes for Blogger and is an expert in software app development.
You can contact him at alex.george@corenetworkz.com.
Alex, can you name out a few devices working in the OSI physical layer?
ReplyDeleteYes Tito,
DeleteI have updated the article with a list of devices working in the Physical Layer.
Hello Alex,
ReplyDeleteWhat exactly does the physical layer do in a network?
I have added the functions of the physical layer, James.
Delete