Mobile Equipment IDentity

Description

The Mobile Equipment IDentity (MEID) is a globally unique 56-bit identifier assigned to physical mobile devices, originally defined by 3GPP2 for CDMA2000 systems. In the context of 3GPP specifications, it is defined to support interworking and interoperability scenarios where a device or network element originating from a 3GPP2 ecosystem needs to be identified within a 3GPP network (e.g., LTE, 5G). The MEID is structurally different from the 3GPP IMEI; it is typically represented as a 14-digit hexadecimal number (or an 18-digit decimal equivalent) comprising a Regional Authority code, a Manufacturer code, and a serial number.

Within 3GPP architecture, the MEID is handled as an alternative equipment identifier, particularly relevant for devices that are dual-mode or for networks that have migrated from CDMA to LTE/5G. Protocols like the 3GPP TS 29.274 (GTPv2-C) and TS 24.229 (IP multimedia call control) specify how the MEID can be encapsulated and transported in signaling messages. For instance, in scenarios involving inter-RAT mobility or roaming between 3GPP and 3GPP2 networks, the MEID may be used by network functions to uniquely identify the equipment. It can be carried in information elements similar to how the IMEI is used, allowing core network entities like the MME, SGSN, or PCRF to process it.

Its functional role parallels that of the IMEI/MEI: equipment identification, theft prevention, and device management. A network operator can maintain an Equipment Identity Register (EIR) that supports both IMEI and MEID checks. When a device with an MEID attaches, the network can query the EIR to determine if the device is permitted on the network. This is crucial for maintaining security policies across heterogeneous device populations. The MEID's inclusion in 3GPP specs ensures that networks can seamlessly identify and manage legacy CDMA devices as operators converge their networks towards unified 3GPP standards, facilitating a smoother technological transition.

Purpose & Motivation

The MEID was created within the 3GPP2 domain to fulfill the same fundamental need as the IMEI in GSM/UMTS: providing a unique, permanent equipment identifier for CDMA handsets. Its adoption into 3GPP specifications was driven by the practical necessity of network convergence and inter-standard operation. As mobile operators began deploying 3GPP-based LTE networks and decommissioning older CDMA networks, there was a clear requirement for these new networks to recognize and manage the millions of existing CDMA devices that might access them, especially during transition periods or through roaming agreements.

This inclusion addresses the limitation of having separate, incompatible equipment identity schemes for different radio technologies, which would hinder unified security policies (like a single blacklist for all devices) and complicate device management for operators running multi-technology networks. By defining the MEID in 3GPP specs, the standards body enabled a bridge between the two worlds, allowing core network functions to handle equipment identity agnostically, whether it originates from a native 3GPP UE or a device from the 3GPP2 lineage. This supports fraud prevention, lawful interception, and accurate device analytics in a consolidated manner.

Key Features

• 56-bit unique identifier for mobile equipment, rooted in 3GPP2 (CDMA)
• Defined in 3GPP for interoperability and interworking scenarios
• Typically represented as a 14-digit hexadecimal number
• Used for equipment identification and EIR queries in multi-technology networks
• Carried in 3GPP signaling protocols (e.g., GTPv2-C, Diameter)
• Supports management of legacy CDMA devices in 3GPP networks

Evolution Across Releases

Defining Specifications