Devices

A device is piece of hardware that uses wireless services. Each device contains a physical card called a SIM (subscriber identity module) that enables the device to communicate wirelessly. Each device is associated with a single account. Within Control Center, the terms device and SIM are used interchangeably. Several other terms are also used to describe a device: ICCID, MSISDN, IMSI, terminal, and even subscriber.

Here are some more related definitions.

Device Terms and Definitions

Term	Definition
SIM	A SIM is a physical card within a device that enables the device to communicate wirelessly. Each SIM has a status that describes its readiness for use (for example, Inventory, Test Ready, Activated, and Retired; see SIM Status Values). Unless there is a particular reason to distinguish between a SIM card and a device, the documentation uses the term device.
ICCID	ICCID is the primary unique identifier for a SIM in Control Center. Like a serial number, the ICCID is typically printed on the SIM card itself and cannot be changed.
MSISDN	An MSISDN is a phone number associated with a device. Over a period of time, you can use the same phone number for multiple devices, for instance, if you retire the original device for a newer model. Consequently, Control Center does not use the MSISDN to uniquely identify a device.
IMSI	An IMSI is a unique identifier that associates a SIM card with a particular mobile network. This code is composed of a country code, a mobile network code, and a mobile subscription ID number.
Subscriber	Subscriber is a billing term that identifies a device using a rate plan. Control Center invoices use this term when referring to devices. In general, for the sake of clarity and consistency, the documentation uses the term device rather than subscriber. However, there are places in the user interface where the term Subscriber is used. In those situations, the documentation uses the same term.