This document discusses the numbering format for M2M devices. It notes that the numbering format follows E.164 standards with a 12 digit number excluding the top level country code. The number is broken down into an access code, service trunk code, provider identification code of 6 digits, and device identification number of 4 digits. Each provider identification code can support up to 100,000 device identification numbers for a total block capacity of 1 billion numbers.