Let’s have some Network Security Interview Questions

Hello Folks 👋,

Parth, this side from BUG XS team. In this blog I am going to discuss about some commonly asked Network Security interview questions. You can find my other write-ups here.

Define protocol

• Protocol is a defined set of rules that decide how devices in a network will
  communicate, irrespective of their internal process, design, and structure.
• For example, File Transfer Protocol(FTP) helps transfer files between devices.

Factors that affect the performance of a network

• Factors:

1. Bandwidth: It is the amount of data that a medium can transfer.
2. No of users: The no of users is inversely proportional to bandwidth. i.e if there are 6 device in a network, each device will get 1/6th of total bandwidth.
3. Error rate: Noise and external interference might alter the data bits
   sent and lead to an error.

Difference between wired and wireless LAN

• In wired connection, Nodes are connected with the help of Ethernet cable.All the devices in a wireless network can be connected with the help of wireless signal.
• Data transfers at a faster rate in wired connections as compared to a
  wireless connection.

How to prevent ARP spoofing?

• Packet Filtering is the best way to prevent ARP Spoofing. It blocks the fishy packets coming from unknown source.
• software's like XArp can help to detect malicious packets.
• Last but not the least, use of HTTPS can help you to authenticate data.

How to prevent IP address spoofing

• Use of Access Control list to deny Private IP address: You can limit user to access files from server, other networks and increase the performance of the network.
• Filter traffic both the ways i.e traffic coming to the system and traffic going from the system. So that even the spoofed IP address wont send any sensitive data from the server to victim’s connection.

What are Dynamic IP and Static IP

Static IP:

• Static IP’s are provided by your ISP and they do not change at all.
• Device using Static IP can be traced easily because IP addresses are unique per system and they do not change.
• Maintenance cost is higher.

Dynamic IP

• They change every time to connect to the network. (Wired or wireless)
• It is very difficult to trace IP address because it changes , when you are connected to new network. For eg, every-time you change your WiFi connection or VPN connection IP is changed.
• Maintenance cost is less.
• Used when data needs high security.