The data telemetry system disclosed is a complete data communications systems suitable for use by utilities such as electric companies, gas companies and water companies which can be used for meter reading and load management at individual subscribers premises. Elements of the system can also be used as a power load carrier in a premise specific local area network (LAN). With the system is disclosed, all 10,000 subscribers per exchange can be serviced. It will be understood that data can be multiplexed between a central office location and remote subscribers for any suitable purpose with the data system as disclosed. A packet switching structure is disclosed having eight to thirty-two bytes in the data message. This packet is routed between the utility and remote subscriber with routing headers being added and deleted as required by the network modules. Each successive layer of the multiplexing and switching hierarchy submultiplies the aggregate 10,000 channel capacity into fewer channels. Both time and space division switching and multiplexing are used.