In telecommunications and anywhere else, redundancy is a secondary system that backs up a primary system. Redundancy is designed to prevent a failure of service and loss of data. This can include anything from the simple backing up of data to multiple instances of hardware. If you have an external hard drive and back-up all of your data to it, the external hard drive is redundant to your system drive(s), and the backed-up data is redundant to your system data. Think of redundancy as a copy (clone) of the original.

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