Redundant Network Design: How It Keeps Your Network Always Online

[johny899]

Have you ever had a situation where a web application becomes unresponsive? I have, and in many cases it was due to there not being a backup pathway. This is why we want to implement a redundant network design to provide reliable continued function of our network in the event of a failure. Now let me break it all down simply.

What Is A Redundant Network Design?​

Think of it as having two or more pathways for your data; if one path is blocked, the data simply reroutes down the open path. I once designed a little office network that just had one router, when it failed the whole network came to a standstill. That is the purpose of redundancy, to keep a single network failure from bringing the entire service down.

Key Aspects of Redundancy​

Redundant networks are far more than just conduits for empty cables. They usually come complete with the following:

• Two more routers, and switches - if one fails, one will take its place.
• Two internet connections - if the first internet service provider fails, it does not take your network down with it.
• Back up power (battery) supply to see devices through until the power is restored.
• Load balancers to equalize traffic so that one device is not overloaded.

Major cloud services like AWS or, Google Cloud hardly ever go offline, at least not all of them--this is redundancy at work!

How It Keeps The Network Available​

Multiple network paths equal network availability, even if one of the paths goes down. For example, if one switch goes down, another switch will still push the traffic to its intended destination. Users have no idea this is going on. From what I've seen, when a company has redundant networks, it has far fewer outages.

An Example

A company that only has one internet connection. When that internet connection goes down, employees are unable to email or utilize online resources because there is no redundancy. Now imagine, this company has two different internet connections and two failover devices, then when one of the internet connections, switches, or the internet router goes down, they can still operate reliably as before. THAT is the benefit of having redundant network design.

Final Thoughts​

In a network design, redundancy might feel like unnecessary work, but in the end it is beneficial. More lines to the internet, more backup devices, and even smart traffic management will keep a network running in the event of a failure. This is why many large websites do not go down, their common factor is redundancy. So if you want your network to remain running, this is not an option, it is a dead serious goal.