Networking Interview Questions

A list of top frequently asked networking interview questions and answers are given below.

1) What is network?

A network is a set of devices that are connected with a physical media link. In a network, two or more nodes are connected by a physical link or two or more networks are connected by one or more nodes.

2) What is the criteria to check the network reliability?

The reliability of a network can be measured on following factors:

• Downtime: The downtime is defined as the required time to recover.
• Failure Frequency: It is the frequency when it fails to work the way it is intended.

3) What is bandwidth?

Every signal has a limit of upper range frequency and lower range frequency. The range of limit of network between its upper and lower frequency is called bandwidth.

4) What is a node and link?

A network is a connection setup of two or more computers directly connected by some physical mediums like optical fiber or coaxial cable. This physical medium of connection is known as link and the computers that it is connected are known as nodes.

5) What is a gateway? Is there any difference between gateway and router?

A node that is connected to two or more networks is commonly known as gateway. It is also known as router. It is used to forward messages from one network to another.

6) What is DNS?

DNS is an acronym stands for Domain Name System. It is a naming system for all the resources over internet which includes physical nodes and applications. It is used to locate to a resource easily over a network.

7) What is DNS forwarder?

A forwarder is used with DNS server when it receives DNS queries that cannot be resolved quickly. So it forwards those requests to external DNS servers for resolution.

8) What are the different types of networks?

Networks can be divided on the basis of area of distribution. For example:

• PAN (Personal Area Network): Its range limit is up to 10 meters. It is created for personal use. Generally personal devices are connected with this network. For example: computers, telephones, fax, printers etc.
• LAN (Local Area Network): It is used for a small geographical location like office, hospital, school etc.
• HAN (House Area Network): It is actually a LAN that is used within a house and used to connect homely devices like personal computers, phones, printers etc.
• CAN (Campus area Network): It is a connection of devices within a campus area which links to other departments of the organization within the same campus.
• MAN (Metropolitan Area Network): It is used to connect the devices which spans to large cities like metropolitan cities over a wide geographical area.
• WAN (Wide Area Network): It is used over a wide geographical location that may range to connect cities and countries.
• GAN (Global Area Network): It uses satellites to connect devices over global are.

9) What is POP3?

POP3 stands for Post Office Protocol version3. POP is responsible for accessing the mail service on a client machine. POP3 works on two models such as Delete mode and Keep mode.

10) What do you understand by MAC address?

MAC stands for Media Access Control. It is the address of the device at the Media Access Control Layer of Network Architecture. It is a unique address means no two devices can have same MAC addresses.

11) What is IP address?

IP address is a unique 32 bit software address of a computer in a network system.

12) What is private IP address?

There are three ranges of IP addresses that have been reserved for IP addresses. They are not valid for use on the internet. If you want to access internet on these private IPs, you must have to use proxy server or NAT server.

13) What is public IP address?

A public IP address is an address taken by the Internet Service Provider which facilitates you to communication on the internet.

14) What is APIPA?

APIPA is an acronym stands for Automatic Private IP Addressing. This feature is generally found in Microsoft operating system.

15) What is the full form of ADS?

ADS stands for Active Directory Structure.

16) What is RAID?

RAID is a method to provide Fault Tolerance by using multiple Hard Disc Drives.

17) What is anonymous FTP?

It is method of granting user access to files in public server.

18) What is Domain Name System?

There are two types of client/server programs. First is directly used by the users and the second supports application programs.

The Domain Name System is the second type supporting program that is used by other programs such as to find the IP address of an e-mail recipient.

19) What is link?

A link is connectivity between two devices which includes the cables and protocols used in order to make communication between devices.

20) How many layers are in OSI reference model?

There are 7 layers in OSI reference model.

1. Physical Layer
2. DataLink Layer
3. Network Layer
4. Transport Layer
5. Session Layer
6. Presentation Layer
7. Application Layer

21) What is the maximum length allowed for a UTP cable?

The maximum length of UTP cable is 90 to 100 meters.

22) What is RIP?

RIP stands for Routing information Protocol. It is accessed by the routers to send data from one network to another.

23) What do you understand by TCP/IP?

TCP/IP is short for Transmission Control Protocol /Internet protocol. It is a set of protocol layers that is designed for exchanging data on different types of networks.

24) What is netstat?

The "netstat" is a command line utility program. It gives useful information about the current TCP/IP setting of a connection.

24) What do you understand by ping command?

The "ping" is a utility program that allows you to check the connectivity between the network devices. You can ping devices using its IP address or name.

25) What is Sneakernet?

Sneakernet is the earliest form of networking where the data is physically transported using removable media.

26) What is RSA Algorithm?

RSA is short for Rivest-Shamir-Adleman algorithm. It is mostly used for public key encryption.

27) How many layers are in TCP/IP?

There are basic 4 layers in TCP/IP:

4- Application Layer

3- Transport Layer

2- Internet Layer

1- Network Layer