Retiary organisation is an organizational method which needs a complex mapping or guidance system for navigation. In blood circulation, telephone networks or power distribution it means that many alternative routes are available to reach a destination passing through many nodes. To connect any two nodes needs a guide or map. In the human context each member of a network needs an address(or phone number) to find any other individual (node) in the net. In electronic devices the points in networks are also identified and accessed by unique addresses.