US Patent 7510090 Rack-mounting system for improving redundancy

A rack-mounting system includes a rack with a number of shelves for mounting electronic modular components. At least two modular components are mounted on each shelf, each component with width approximately equal to W/n, where W equals the width of the shelf and n equals the maximum number of modular components to be mounted on a single shelf. Each modular component is fully self-contained, stand-alone, and operates with full independence of the other self-contained, stand-alone components. At least two modular components have the same function. Means is provided for switching out a defective component and switching in a standby component that performs the same function, thus enhancing redundancy.