Understanding Active and Passive Redundancy in System Design

Active Redundancy

Active Redundancy is when you have two or more things doing the same job at the same time. If one of them can’t do the job, the others steps in right away to keep running smoothly.

Example:

Think of a website with two servers working together. They both show the website to people. If one server has a problem, the other sever quickly takes over to make sure the website keeps running without any issues.

Passive Redundancy

Passive Redundancy is like having a backup that doesn’t do anything until it is needed. It stays quiet in background, ready to jump in and help only when there’s a problem.

Example:

In computer networks, you can have a spare or backup router. The backup doesn’t do any work until main router has a problem. When main one fails, the spare router starts working to keep the network connected.

In Computer Science, redundancy means having backups or duplicates of things to make sure your computer systems keep working even if something breaks. Imagine you have important files on your computer. If you only have them in one place and your computer crashes or the files get deleted, you’ll lose everything. But if you also keep copies of those files on an external hard drive or in the cloud, that’s redundancy.

Redundancy helps prevent big problems when things go wrong. It can be applied to different parts of a computer system, like having extra computer servers, multiple copies of data, or backup internet connections. This way, if one part fails, the redundant one takes over, and everything keeps running smoothly.