Networking Interview Questions and Answers

This tutorial lists frequently asked networking interview questions and their answers. You can use this collection to prepare for any entry-level networking interview.

What is a password?

A password is a secret word used to prove a user's identity in the authentication process. If a resource is password protected, you can access it only after providing the correct password.

What is the UAC?

It is a security feature on Windows systems that prevents unauthorized applications from running without user permission.

At which port does HTTP operate?

HTTP operates at port 80.

At which port does HTTPS operate?

The HTTPS operates at port 443.

What is DHCP?

DHCP stands for Dynamic Host Configuration Protocol. Every node on an IP network needs an IP address to communicate with others. Assigning and managing IP addresses becomes difficult if a network has many hosts. DHCP solves this issue. It automatically provides and manages IP addresses on hosts.

What is DNS?

DNS stands for Domain Name System. It maps a name with a numeric address. Electronic devices (such as computers and phones) use numeric identities (phone numbers and IP addresses) for addressing. DNS maps these numeric identities with names.

What is an encoder?

Any device or software that prepares data for transmission is considered an encoder.

What is a decoder?

Any device or software that converts the encoded data to its actual format is considered a decoder.

What does the Physical layer define?

The physical layer defines the standards and protocols for the media and devices used to connect the devices physically in the network. It addresses only those equipment and technology that work with electronic signals, such as NICs, connectors, repeaters, and cables.

It does not cover any device that handles data in other formats besides the signal (analogue and digital) format. For example, Hubs and Switches are both used to connect multiple computers. A switch handles data in the frame format, while a Hub handles data in the signal format. Because of this, a Hub is a physical layer device, while a switch is a Data Link layer device.

In which layers of the OSI model does Ethernet work?

Ethernet works in the first two layers of the OSI model. These layers are the Physical layer and the Data Link layer.

What is the term packet defined in the OSI model?

The term packet expresses the encapsulated data transmitted and received at the network layer.

What is the POP?

POP (Post Office Protocol) is a protocol. The client computer uses it in the email system to retrieve emails from the email server.

Based on the network relationship, how many types of networks are there?

Based on the network relationship, there are two types of networks: peer-to-peer and client/server.

What is the encapsulation?

Encapsulation is the process of packing data for transportation.

What is a peripheral?

A peripheral is a device or hardware that is added to a computer to add additional functionality or to improve existing functionality.

What does the 10Base5 stand for?

In 10Base5 architecture, 10 stands for speed, Base stands for Baseband transmission and five stands for 500 meters distance.

Which standards define Gigabit Ethernet?

IEEE802.3z and IEEE802.3ab standards specify Gigabit Ethernet.

What does the standard IEEE802.3z define?

IEEE802.3z standard defines the following Gigabit Ethernet implementations: -

1000BaseSX (1000Mbps speed, MMF Fiber optical cable, 550Meter maximum distance)
1000BaseLX (1000Mbps speed, SMF Fiber Optical cable, 3Kilometers distance)
1000BaseCX (1000Mbps speed, coaxial cable, 25meter distance)

What does an access method describe?

An access method describes how a computer transmits data in the network.

What are the differences between different Ethernet architectures based on speed, distance, and cable?

The following table compares Ethernet architectures based on speed, distance, and cable.

What is the maximum distance limit of a UTP cable?

The distance limit of a UTP cable is 100 meters.

Which cable is required to build a 100BaseT network?

To build a 100BaseT network, UTP (CAT-5) cables are required.

How much distance does an SMF (single-mode fibre) cable support?

An SMF cable supports a maximum distance of 2 km.

Which connector connects a Thinnet cable with NIC?

The BNC (British Naval Connector) connector connects the Thinnet cable with the NIC.

Which connector connects a Thicknet cable with NIC?

The AUI (Adapter unit interface) connector connects the Thicknet cable with the NIC.

How is a straight-through UTP cable made?

In a Straight-through UTP cable, all pins match on both sides. Pin-1 connects with Pin-1; Pin2 connects with Pin2, and so on. Each pin on one side connects with the same number of the pin on another side.

What are the two most common network types based on the geographical location?

LAN (Local Area Network) and WAN (Wide Area Network).

What is the difference between point-to-point topology and point-to-multipoint topology?

In a point-to-point topology, one system connects with another system directly. In point-to-multipoint topology, all systems connect through a centralized device.

Where is Mesh topology used?

Mesh topology is used in WAN networks to build alternative paths between networks.

What is the main advantage of Mesh topology?

It creates redundant links between nodes that keep the network alive till the last active link.

Why a system cannot monopolize the Token Ring LAN?

Each system gets the token only for a specific period. Once that period has expired, it must have released the token.

What are the differences between TFTP and FTP?

TFTP (Trivial File Transfer Protocol) uses the UDP protocol for data transmission. It neither uses an authentication process before transmission nor uses any mechanism to ensure data integrity throughout the transmission.

FTP (File Transfer Protocol) uses TCP protocol for data transmission. It uses an authentication process before transmission and several mechanisms to ensure data integrity throughout the transmission.

TFTP is only for use in private networks between known devices. Using it in the public network is not safe.
FTP is for both public and private networks. You can use it on both networks.

What is the 10BaseFL architecture?

The 10BaseFL is the extended version of the 10BaseT architecture. It uses fibre optic cable instead of UTP cable. Administrators use it to build the backbone network.

What are the similarities and differences between 100BaseTX and 100BaseFX?

Similarities: - Both architectures use Baseband technology for data transmission and provide a maximum speed of 100Mbps.

Differences: - 100BaseTx uses UTP (CAT-5) cable while 100BaseFX uses fibre optical cable.

What are the differences between the STP cable and the UTP cable?

STP cable has an additional layer of insulation on each pair of twisted wires that protects the quality of signals in the wires. On the positive side, STP cable is more reliable. On the negative side, it is more expensive than a UTP cable.

What are the differences between the single-mode fibre optic cable and the multimode fibre optical cable?

SMF (Single Mode Fiber) cable uses a single ray of light to carry the signals. In contrast, MMF (Multimode Fiber) cable uses multiple rays of light to carry the various signals simultaneously.

What is the Crosstalk?

Crosstalk is the interference between adjacent wires.

What is the distance limit of 10Base2 Ethernet?

Theoretically, it supports 200 meters distance. Practically, it supports only 185 meters. It uses ThinNet coaxial cable that has a distance limitation of 185 meters.