Around ten thousand of New Zealand’s most remote households connect to the public switched telephony network (PSTN) via customer multi-access radio (CMAR). Although copper loops connect up these neighborhoods of between ten and sixty houses, the loops are disconnected from major fibre optic backbones because of the cost of running cable across rough territory. These systems provide excellent voice service, but data service is limited to 14,400 bits per second – or around 0.1% of the capacity of a modern ADSL connection.
The diagram below illustrates a typical CMAR topology. It shows a local copper loop linking houses, an outstation linking the loop to a radio tower, and a radio linking network connecting the system back in to a regional centre with fibre optic network access.