Top 50 Basic Networking Interview Questions and Answers [2025]

Basic Networking Interview Questions and Answers 

IoT gadgets are replacing the core human lifestyle as the globe moves into a new era.  Many certified networking experts encounter a variety of issues during networking job interviews for different designations in the modern world.

Through this fascinating blog article, Craw Security, the top networking institute in India, has provided you with the Top 50 Basic Networking Interview Questions and Answers.

As a result, we have provided more details on the key questions and answers that may help explain the precise scope and approach of networking Q&As, which may surely help applicants who express a strong interest in them get acceptable positions.  Learn more about reading these FAQs.

Q. 1: What is a network?

A group of two or more devices linked by communication channels that enable resource and data sharing is called a network.  Local area networks (LANs), wide area networks (WANs), and the Internet are a few examples of networks.

Q. 2: What is a switch?

A switch is a type of network equipment that joins several networks or devices. It makes it possible to rapidly and simply link various devices to a network so that they can share resources or data. Additionally, it enables the establishment of distinct networks for various users or gadgets.

Q. 3: What is a router?

Data packets are forwarded between computer networks by routers, which are networking devices.  Local area networks (LANs) and wide area networks (WANs) of various sizes are connected by routers.

Furthermore, routers employ specialized software to choose the most efficient path for data packets to follow when moving between networks.  Network address translation (NAT), which enables several devices on the same network to share a public IP address, is another capability that routers can offer in addition to firewall security.

Q. 4: What is a gateway?

A gateway is a network node that uses a distinct communication protocol to link two networks. It facilitates the interchange of data and information between two networks by serving as a bridge between them.  Data can be transported between two networks that would not otherwise be compatible because to its ability to convert between several network protocols.

Q. 5: What is a firewall?

A firewall is a type of security system that uses preset security rules to monitor and regulate all network traffic, both inbound and outbound.  It is employed to filter network traffic and safeguard private networks against unwanted access.  Furthermore, firewalls are usually placed between an untrusted external network, like the Internet, and a trusted, secure internal network.

Q. 6: What is a VLAN?

A virtual local area network, or VLAN, is a logical collection of network devices that, despite their possible physical locations on separate networks, act as though they are on the same local network.  Network segmentation, broadcast traffic reduction, security, and traffic management are all enhanced by VLANs.

Q. 7: What is a subnet?

An IP network's logical division is called a subnet. To increase network security and performance, it is commonly used to split an IP network into two or smaller networks. A distinct subnet mask is used to identify each subnet.

Q. 8: What is a broadcast domain?

A computer network's broadcast domain is a logical segment where all nodes can communicate with one another via broadcast at the data link layer.  Additionally, a broadcast domain may cover several LAN segments or remain within a single LAN segment.

Q. 9: What is a collision domain?

When data packets are sent on a shared network segment, they may collide with one another in a collision domain.  Furthermore, it is typically brought on by a network design flaw, like connecting many devices to the same switch port or employing hubs in place of switches.

Furthermore, any two network devices linked to the same logical segment can detect each other's packets in a collision domain.

Q. 10: What is a LAN?

Within a relatively small area, such a home, workplace, school, or building, a LAN (Local Area Network) is a group of computers and other devices that are connected to one another and share resources.  Additionally, wired or wireless networking technologies are usually used to connect the devices in a LAN.

Q. 11: What is a WAN?

One kind of computer network that spans vast geographic regions, like nations, states, or provinces, is called a WAN (Wide Area Network).  Wide area networks (WANs) are also used to link computers and other devices over long distances.  They can also be utilized for teleconferencing, file sharing, and other purposes.

Q. 12: What is a VPN?

Using the public Internet to establish a private network connection is known as a virtual private network, or VPN. By directing users' traffic through a secure tunnel, it then enables them to send and receive data in a secure and anonymous manner. VPNs can also be used to conceal your online activity from your Internet Service Provider (ISP), access geo-restricted websites and services, and add an extra degree of security when utilizing public Wi-Fi networks.

Q. 13: What is an IP address?

Every device linked to a computer network that communicates via the Internet Protocol is given a numerical label known as an IP address (Internet Protocol address). Additionally, the IP address has two main purposes:

• Host or network interface identification
• Location addressing.

Q. 14: What is a subnet mask?

The number that divides an IP address's host and network components is called a subnet mask.  Furthermore, it is really utilized to help route data to the appropriate network and identify which subnet an IP address belongs to.

Q. 15: What is DHCP?

For Dynamic Host Configuration Protocol, DHCP is an acronym. It is a protocol that makes it possible to handle IP address distribution inside a network quickly, automatically, and centrally.

Additionally, network devices are automatically assigned IP addresses, subnet masks, default gateways, and other network configuration parameters by DHCP.

Q. 16: What is DNS?

The Domain Name System, or DNS, is a system that translates website names that are legible by humans into numerical IP addresses that are readable by computers.

Other data, such the list of mail servers connected to a domain name, is also stored by DNS. Because it offers a global, dispersed directory service, it is a crucial part of the Internet.

Q. 17: What is a DNS server?

A computer server that houses a database of public IP addresses and the hostnames that go with them is known as a DNS (Domain Name System) server.  It is also used to convert IP addresses (like 192.168.1.1) into domain names (like www.example.com).

Additionally, this ensures that a user is directed to the correct website when they type a website address into a web browser.

Q. 18: What is a default gateway?

A network device that serves as an access point or gateway for other network devices to connect to the larger Internet is known as a default gateway.  Furthermore, it is actually a dedicated server, a router, or a modem. It is in charge of making the Internet and other external networks accessible.

Q. 19: What is NAT?

Network Address Translation, or NAT for short, is a system that converts a collection of private IP addresses into a single public IP address.  It is then used to preserve public IP addresses and grant external access to inside networks. Both residential and business networks frequently use it.

 

Computers interact over the Internet using a language called Transmission Control Protocol/Internet Protocol, or TCP/IP. The Internet and many private networks are built on this set of guidelines that control how data is transmitted over networks. Additionally, it is employed for intra-network communication, including Local Area Networks (LANs).

Q. 21: What is a routing table?

Information about the routes that data packets take across a network is stored in a routing table, a type of network-routing data structure.  Typically, it includes some basic information like the route's destination and cost.  Additionally, routers forward packets to their intended location via routing tables. They are also employed to identify the most efficient path for data transfer.

Q. 22: What is a port?

In networks, a port is a communication endpoint where data can be sent and received.  Communication to and from a computer is made possible by this logical construction.

Additionally, its number serves as a genuine notification, setting it apart from competing providers.

Q. 23: What is a packet?

Data sent via a network is called a packet.  It has a header with source and destination addresses as well as other information, including error-checking and sequencing data.  Furthermore, a payload containing the actual data being transmitted over the network comes after the header.  Both wired and wireless networks typically use packets.

Q. 24: What is a protocol?

A protocol is a collection of guidelines that control how two or more networked devices—like PCs, routers, and servers—communicate with one another.  Additionally, protocols allow devices to communicate and process information by facilitating structured, consistent data exchange.

Q. 25: What is a topology?

The spatial interactions between items are described by a mathematical framework called a topology.   Generally speaking, it is a means of characterizing a network's connectedness, encompassing both the logical and physical links among its nodes.

All things considered, topologies offer a means of examining and visualizing the relationships among items, and they may be applied to spot possible issues and enhance network efficiency.

Q. 26: What is a hub?

According to technical definitions, a hub is a networking device that enables several devices to join a single network.  Furthermore, a hub serves as a central point of connection for networked devices, facilitating data sharing and communication between them.

Q. 27: What is a bridge?

A bridge is a construction that joins two or more portions of land or water by spanning a physical barrier, such as a road, valley, or body of water. Furthermore, bridges are usually used to transport goods, people, and automobiles from one side to the other.

Q. 28: What is a NIC?

The Network Interface Card, or NIC for short, is a piece of hardware that enables a computer to connect to a network.  To give the computer access to the network, it is also a physical layer device that can be utilized with Ethernet networks.

Q. 29: What is a MAC address?

For communications on the physical network segment, a network interface controller (NIC) is given a unique identification known as a MAC (Media Access Control) address.  It is often referred to as a physical address or hardware address.  Additionally, it can be used to limit network access and to identify and distinguish devices on a network.

Q. 30: What is ARP?

Address Resolution Protocol is referred to as ARP. Furthermore, it is a protocol that maps an IP address to a MAC address or other physical network address. Additionally, ARP is used to translate an IP address into a physical address and to allow communication between two devices on a network.

Q. 31: What is a proxy server?

A computer or program that serves as a middleman for client requests for resources from other servers is known as a proxy server.  After receiving client requests, a proxy server routes them to the relevant remote server and sends back to the client the responses from the distant server.

Furthermore, proxy servers can be used to mask IP addresses, monitor and filter online traffic, enhance performance, and get around regional limitations, among other things.

Q. 32: What is a VPN concentrator?

A device known as a VPN (Virtual Private Network) concentrator enables several distant users to safely connect to a private network via the internet.  VPNs are typically used to give branch offices, commercial partners, and distant and mobile users secure access to corporate networks.  In addition, the concentrator serves as a gateway, forming a secure tunnel for data transmission by encrypting and decrypting data as it travels through.

Q. 33: What is a DMZ?

A computer network's Demilitarized Zone (DMZ) is a section that is kept apart from the rest of the network, typically by a firewall. Furthermore, although internal connections are prohibited, exterior connections are permitted in this safe region. In this manner, any potential malicious activity or attacks in the DMZ can be contained and isolated without compromising the network as a whole.

Q. 34: What is a NAC?

The language Network Access Control, or NAC for short, is a set of hardware and software tools used to enforce different security rules and regulate access to a computer network. This is well-designed to guarantee that the network can only be accessed by authorized users and devices. Additionally, NAC can be used to guard against outside and internal unauthorized access to an organization.

Q. 35: What is a SAN?

Servers and shared data storage are connected by a fast network of storage devices called a Storage Area Network, or SAN.  Furthermore, it genuinely makes use of the Fibre Channel protocol to transfer massive volumes of data between servers and storage devices in a fast and safe manner.  SANs are also frequently used for replication, disaster recovery, and data backup.

Q. 36: What is a NAS?

The language Network Attached Storage, or NAS for short, is a device that gives a network file-level data storage capabilities. Furthermore, it is authentically connected to a local area network (LAN), enabling users to access it from any network-connected computer. It is frequently utilized in business networks and can be used for file sharing, synchronization, and backup.

Q. 37: What is a WLAN?

WLAN is an acronym for Wireless Local Area Network, a kind of network that enables wireless connections between devices. WLANs are frequently found in homes, workplaces, and public areas like hotels and airports.

Q. 38: What is a LAN extension?

One kind of technology that allows users to increase the range of their local area network (LAN) is a LAN extension.  Furthermore, it enables users to access the same network resources from far-off places just like they could if they were physically present at the LAN.  Furthermore, when users need to access the same network resources from different locations, LAN extensions are commonly utilized in large organizations like government offices, hospitals, and universities.

Q. 39: What is a VPN gateway?

One kind of networking device that offers safe access to a company's internal networks and resources from an external network, like the Internet, is a VPN gateway.   It subsequently serves as a bridge between the two networks, offering a safe channel for data transmission.   VPN gateways are also used to guard private information, guarantee safe remote access, and stop hostile attacks on business networks.

Q. 40: What is a WAP?

Wireless Application Protocol is referred to as WAP.  It is a worldwide, open standard for creating applications that are accessible through wireless networks, which offer a platform for the distribution of voice, data, and other services on PDAs, cell phones, and other wireless devices.

Q. 41: What is a VPN tunnel?

A virtual private network (VPN) tunnel is a secure connection that genuinely enables safe and secure data transit via the internet between two or more systems. In this sense, a VPN tunnel protects the data being transmitted over the connection by utilizing encryption and other security measures. It is also a secure method of accessing data and resources from distant locations because it is a private connection that is hidden from other networks.

Q. 42: What is a VTP?

The Cisco proprietary Virtual Trunking Protocol, or VTP for short, is used to control trunk port configuration over a network of Ethernet-connected Cisco switches.   Furthermore, it enables the administrator to set up the trunk links just once, and it will spread that setting to every other switch in the network.   Additionally, VTP helps to lessen the amount of manual setup required for big networks.

Q. 43: What is a VLAN tagging?

Generally speaking, VLAN tagging is a technique used to locate packets moving over a network and allocate them to a particular virtual local area network (VLAN).   A VLAN tag is applied to a packet upon its arrival at a port on a network switch, allowing it to be recognized and routed to the appropriate location.   Additionally, a network can be divided into several broadcast domains for enhanced security and performance by using VLAN tagging.

Q. 44: What is a VLAN trunk?

A point-to-point connection that transports traffic for several VLANs between two network devices is called a VLAN trunk.  In technical terms, it is also referred to as an 802.1Q trunk or VLAN trunk port, which enables the segmentation of a local area network (LAN) by enabling several VLANs to be carried over a single physical connection.

Q. 45: What is a VLAN hopping?

Attackers can access traffic on a different VLAN from the one they are connected to by using a technique known as VLAN hopping.  The ability of the attacker to access a network or its resources that they shouldn't have access to is known as a network attack.  Furthermore, this is typically accomplished by taking advantage of flaws in the VLAN or network configuration.

Q. 46: What is a VPN pass-through?

Devices can create outgoing VPNs thanks to a router function called VPN pass-through. Furthermore, its primary function is data forwarding between two endpoints, enabling safe data transfer between two networks. This specific feature technically supports both L2TP and PPTP protocols.

Q. 47: What is a VPN split-tunneling?

One feature that lets the user choose which traffic should go through the VPN tunnel and which should go around it is called VPN split-tunneling.  In this sense, programs that need a direct Internet connection or those with constrained bandwidth may find it useful.  Additionally, when connected to the VPN, users can access local resources like file sharing and printers.

Q. 48: What is a VPN load balancing?

To increase bandwidth and boost performance, network traffic is divided among several VPN connections using a technique known as VPN load balancing.  To distribute the load and improve overall performance, this strategy is implemented by directing traffic over several VPN connections.  Additionally, this is helpful for people who wish to access material from various locations or for enterprises that need to access globally scattered applications or resources.

Q. 49: What is a GRE tunnel?

Virtual private network (VPN) connections known as GRE (Generic Routing Encapsulation) tunnels employ the GRE protocol to establish a secure connection between two or more distant sites via the Internet or other networks.  Additionally, routers can exchange data over public networks like the Internet by using GRE tunnels to establish secure connections.

Q. 50: What is a VLAN ID?

A virtual local area network (VLAN) is identified on a network by its VLAN ID, which is a number that is allocated to it.   Furthermore, a network can be divided into several logical networks using this technique, which is commonly employed to divide various departments or functions inside an organization.