Network Redundancy Design

If there is a single point of failure and it fails...

Network redundancy is a simple concept to understand.

If there is a single point of failure and it fails, then… the world is on fire!

If there is a secondary point, then when the main point fails, there is still another means to stay alive. 

Network redundancy therefore is a process of additional or alternate instances of network devices, equipment and communication mediums being installed within the network infrastructure.  

It is a method for ensuring network availability in case of a network device or path failure and unavailability. It provides a means of network failover.

Most network redundancy planning is flawed

Until recently, our options for mitigating network outages have been limited.

Traditionally, most companies have taken the approach of replicating the primary wired link with a second or even third wired link, and to align each link with a different network provider.

The flaw with this approach is that the secondary cable, more often than not, is laid in the same physical trench as the primary, with both wires exposed to the same risks. These might be weather-related flooding or bushfire, or man-made interference from capital works.

Of course, there is always the option to install an additional wire through a different entrance, but the cost in both time and money is usually prohibitive, and therefore rarely utilised.