The use of this NANP numbering resource is to communicate with both fixed and Mobile Devices, some of which may be unattended. This resource may be used for applications enabling machines, which would include but not be limited to wireless devices and appliances, the ability to share information with back-office control and database systems and with the people that use them. Service is limited only by terminal and network capabilities and restrictions imposed by the service provider.
5XX-NXX codes are in the format 5XX-NXX-XXXX. 5XX-NXX codes, each subsuming a block of 10,000 numbers, are assigned to service providers.