Networking Interview Question

Categories: Hardware & Networking

Ques 1. What are the different types of VPN?

Ans. Few types of VPN are:

Access VPN: Access VPN is used to provide connectivity to remote mobile users and telecommuters. It serves as an alternative to dial-up connections or ISDN (Integrated Services Digital Network) connections. It is a low-cost solution and provides a wide range of connectivity.

Site-to-Site VPN: A Site-to-Site or Router-to-Router VPN is commonly used in large companies having branches in different locations to connect the network of one office to another in different locations. There are 2 sub-categories as mentioned below:

Intranet VPN: Intranet VPN is useful for connecting remote offices in different geographical locations using shared infrastructure (internet connectivity and servers) with the same accessibility policies as a private WAN (wide area network).

Extranet VPN: Extranet VPN uses shared infrastructure over an intranet, suppliers, customers, partners, and other entities and connects them using dedicated connections.

Ques 2. What are nodes and links?

Ans. Node: Any communicating device in a network is called a Node. Node is the point of intersection in a network. It can send/receive data and information within a network. Examples of the node can be computers, laptops, printers, servers, modems, etc.

Link: A link or edge refers to the connectivity between two nodes in the network. It includes the type of connectivity (wired or wireless) between the nodes and protocols used for one node to be able to communicate with the other.

Ques 3. What is the network topology?

Ans. Network topology is a physical layout of the network, connecting the different nodes using the links. It depicts the connectivity between the computers, devices, cables, etc.

Ques 4. Define different types of network topology

Ans. The different types of network topology are given below:

Bus Topology:

a. All the nodes are connected using the central link known as the bus.

b. It is useful to connect a smaller number of devices.

c. If the main cable gets damaged, it will damage the whole network.

Star Topology:

a. All the nodes are connected to one single node known as the central node.

b. It is more robust.

c. If the central node fails the complete network is damaged.

d. Easy to troubleshoot.

e. Mainly used in home and office networks.

Ring Topology:

a. Each node is connected to exactly two nodes forming a ring structure

b. If one of the nodes are damaged, it will damage the whole network

c. It is used very rarely as it is expensive and hard to install and manage

Mesh Topology:

a. Each node is connected to one or many nodes.

b. It is robust as failure in one link only disconnects that node.

c. It is rarely used and installation and management are difficult.

Tree Topology:

a. A combination of star and bus topology also know as an extended bus topology.

b. All the smaller star networks are connected to a single bus.

c. If the main bus fails, the whole network is damaged.

Hybrid:

a.It is a combination of different topologies to form a new topology.

b. It helps to ignore the drawback of a particular topology and helps to pick the strengths from other.

Ques 5. What is the DNS?

Ans. DNS is the Domain Name System. It is considered as the devices/services directory of the Internet. It is a decentralized and hierarchical naming system for devices/services connected to the Internet. It translates the domain names to their corresponding IPs. For e.g. interviewbit.com to 172.217.166.36. It uses port 53 by default.

Ques 6. What is the use of a router and how is it different from a gateway?

Ans. The router is a networking device used for connecting two or more network segments. It directs the traffic in the network. It transfers information and data like web pages, emails, images, videos, etc. from source to destination in the form of packets. It operates at the network layer. The gateways are also used to route and regulate the network traffic but, they can also send data between two dissimilar networks while a router can only send data to similar networks.