Introduction to Networking Interview Questions
Most of the software industry is running on a network. A computer that is not in a network is just a piece of a system that cannot be used. A network is a connection of two or more computers using the protocol in a way that they tend to serve information whenever required. Networking Interview questions are common to most fields, be it the position of System Admin, programmer or anyone from the IT branch.
Now, if you are looking for a job related to Networking, you need to prepare for the 2021 Networking Interview Questions. Every interview is indeed different as per the different job profiles. Here, we have prepared the important Networking Interview Questions and Answers, which will help you succeed in your interview.
In this 2021 Networking Interview Questions article, we shall present the 10 most important and frequently used Networking interview questions. Let us have a look at the basic questions which can be asked in an interview on Networking.
Part 1 – Networking Interview Questions (Basic)
This first part covers basic Interview Questions and Answers.
Q1. Explain the seven layers of the OSI reference model?
Below are the seven layers of the OSI reference model:
- Physical Layer: This layer converts data bits into radio signals. An example of this is Ethernet.
- Data Link layer: At the data link layer, data packets are encoded and decoded and are provided to node data transfer.
- Network Layer: This layer transfers variable length data from one node to another. This data is known as a datagram.
- Transport Layer: This layer transfers data between different nodes and keeps giving acknowledgements for data packets. It keeps track of all transmissions and transmission failures.
- Session Layer: This layer manages connections between different systems on a network. It helps in establishing coordinating and terminating connections between all applications.
- Presentation Layer: It transforms data into the form which the application layer will accept.
- Application Layer: This is the last layer with which both end-user and applications interact with. This layer provides services like email, file transfer, etc.
Q2. Explain the concept of DNS?
DNS stands for Domain Name System. It is a naming system that includes physical nodes and their applications. DNS is a way of finding a resource easily over a network. It gives a name to a particular IP address. It is always easy to remember xyz.com that an IPV4 address or IPV6 address. Domain Name System is responsible for assigning Domain names by mapping hierarchically corresponding IP addresses and works.
Let us move to the next Networking Interview Questions.
Q3. Explain in short the meanings of PAN, LAN, HAN, SAN, and WAN?
- PAN: This signifies Personal Area Network. It is a connection that a person uses.
- LAN: This stands for Local Area Network and connects all computers in a small location like school, office, etc.
- HAN: This stands for Home Area Network and helps connect devices from some PCs, phones, fax machines, etc.
- SAN: This stands for Storage Area Network. It is a connection between different storage devices.
- WAN: This is an acronym for Wide Area Network. It connects various devices, phones, printers, etc., over a wide network which can be different cities or countries and even continents.
Q4. What are the uses of cross and standard cables?
These are the basic Networking Interview Questions asked in an interview. A network cable is necessary to connect all systems to be in a network together. This cable can either be straight or crossover. Both these cables have different arrangements which are required for different purposes. A straight cable can be used to connect a computer to a switch, hub, modem or router to the switch. A crossover cable is used when a computer is connected to a computer or a switch with a switch, or a hub with a hub.
Q5. What is a firewall?
A firewall is a network security system that helps in protecting your network from unauthorized access. It averts malignant access from computers outside the network. A firewall also works when you want to limit access to outside users. A firewall mainly consists of hardware devices, software programs or a combination of both these. All the messages coming from a network or going to a network have to pass through this firewall. Security criteria examine firewalls, and the messages which meet these criteria are passed through the network. If the message does not fulfil the criteria, then the message is blocked and not sent to the network further. Firewalls can be installed like any software and can be later customized for getting control over features and security.
Part 2 – Networking Interview Questions (Advanced)
Let us now have a look at the advanced Interview Questions.
Q6. What is a proxy server, and how to protect it?
Proxy servers are servers that prevent external users who are not authorized to access an IP address from accessing it. When data transmission comes into the picture, IP addresses are required, and so are DNS which route the correct IP address to the domain name. Proxy servers also maintain the list of all blacklisted websites to automatically prevent all internal users from any attacks from viruses, worms, etc.
Q7. What is 127.0.0.1 and localhost?
The IP address 127.0.0.1 is reserved for localhost connections. These local host networks are reserved for the biggest customers or some essential people on the internet. To check whether the localhost server is working fine, you must ping the server and check for its response. If it is not responsible, then the reason can be that the server is down or the network card is not in good condition. 127.0.0.1 is a loopback connection, and if you get a response for this, then it signifies that your hardware is in good condition.
Let us move to the next Networking Interview Questions.
Q8. Explain the difference between the Internet, Intranet and Extranet?
All three are terminologies of how a network can be accessed. They define the access levels for each user, which is present inside and outside the network.
- Internet: In this, all applications can be accessed from anywhere by anyone over the worldwide web.
- Intranet: It limits access for users in the same organization. All users outside the organization cannot access this network.
- Extranet: When external users are allowed to access a network of an organization, then it is extranet. They are provided access to a limited application in the organization.
Q9. What is a router?
These are the popular Networking Interview Questions asked in an interview. A router is a physical device that is a gateway between two networks. It does the job of forwarding the data packets from one network to another and builds an interconnection link between the two networks.
Q10. How is VPN used in the corporate world?
A Virtual Private Network allows remote users to connect to an organization’s network securely. All companies, educational institutions make use of VPNs so that users can access the networks remotely.
This has been a guide to the list of Networking Interview Questions and Answers so that the candidate can crackdown these Networking Interview Questions easily. Here in this post, we have studied Networking Interview Questions which are often asked in interviews. You may also look at the following articles to learn more –