Glossary

The glossary contains terms and acronyms that are used in this document.

Access Point Name (APN)

The name of a gateway between a mobile network and another computer network, usually the Internet.

APN

Cat-M1

LTE-M User Equipment (UE) category with a single RX antenna, specified in 3GPP Release 13.

Cat-NB1

Narrowband Internet of Things (NB-IoT) User Equipment (UE) category with 200 kHz UE bandwidth and a single RX antenna, specified in 3GPP Release 13.

Check Digit (CD)

The last one-digit number of the International Mobile (Station) Equipment Identity (IMEI) code used for error detection.

CD

Classless Inter-domain Routing (CIDR)

A method for allocating IP (Internet Protocol) addresses.

CIDR

CS/PS Mode of Operation

A User Equipment (UE) mode of operation. The UE may either register to packet-switched services, circuit-switched services, or both based on the mode of operation. If both are registered, the mode of operation also contains a preference for either of them.

Discontinuous Reception (DRX)

A method in mobile communicaton to conserve the battery of a mobile device by turning the RF modem in a sleep state.

DRX

Dynamic Host Configuration Protocol (DHCP)

A network management protocol used for automatic and centralized management of IP addresses within a network.

DHCP

Electronic Serial Number (ESN)

A unique number embedded on a microchip for identifying mobile devices.

ESN

EPS Mobility Management (EMM)

The Evolved Packet System (EPS) Mobility Management (EMM) sublayer in the Non-access Stratum (NAS) protocol provides mobility service to the UE.

EMM

Evolved Packet System (EPS)

A connection-oriented transmission network in LTE (Long-term Evolution) consisting of an EPC (Evolved Packet Core) and an E-UTRAN (Evolved Terrestrial Radio Access Network).

EPS

Extended Discontinuous Reception (eDRX)

A method to conserve the battery of an IoT (Internet of Things) device by allowing it remain inactive for extended periods.

eDRX

Global Navigation Satellite System (GNSS)

A satellite navigation system with global coverage. The system provides signals from space transmitting positioning and timing data to GNSS receivers, which use this data to determine location.

GNSS

International Mobile (Station) Equipment Identity (IMEI)

A unique code consisting of 14 digits and a check digit for identifying 3GPP-based mobile devices.

IMEI

International Mobile (Station) Equipment Identity, Software Version (IMEISV)

A unique code consisting of 16 decimal digits and two software version digits for identifying 3GPP-based mobile devices.

IMEISV

International Mobile Subscriber Identity (IMSI)

A unique code, usually 15 digits, used for the identification of a mobile subscriber and consisting of an Mobile Country Code (MCC), Mobile Network Code (MNC), and MSIN (Mobile Subscription Identification Number).

IMSI

International Reference Alphabet (IRA)

A seven-bit coded character set for information exchange.

IRA

Maximum Transmission Unit (MTU)

The largest packet or frame that can be sent in a single network layer transaction.

MTU

Mobile Country Code (MCC)

A unique three-digit part of an IMSI code identifying the country of domicile of the mobile subscriber. MCC is used together with the Mobile Network Code (MNC).

MCC

Mobile Equipment (ME)

The physical UE consisting of one of more Mobile Termination (MT) and one or more Terminal Equipment (TE).

ME

Mobile Network Code (MNC)

A code identifying the telecommunications network. The code is defined by ITU-T Recommendation E.212, consists of two or three decimal digits, and is used together with the Mobile Country Code (MCC).

MNC

Mobile Station International Subscriber Directory Number (MSISDN)

A number consisting of a maximum of 15 digits identifying a mobile subscriber by mapping the telephone number to the Subscriber Identity Module (SIM) card in a phone.

MSISDN

Mobile Termination (MT)

A component of the Mobile Equipment (ME) performing functions specific to management of the radio interface. The R interface between TE and MT uses the AT command set. The IMEI code is attached to the MT.

MT

Non-access Stratum (NAS)

In telecom protocol stacks, the highest stratum of the control plane between the core network and UE. The layer is used to manage the establishment of communication sessions and for maintaining communications with the UE as it moves.

NAS

Non-access Stratum (NAS) Signalling Low Priority Indication (NSLPI)

Used by the network for NAS-level mobility management congestion control.

NSLPI

Non-volatile Memory (NVM)

Memory that can retrieve stored information even after having been power-cycled.

NVM

Packet Data Network (PDN)

A network that provides data services.

PDN

Packet Data Protocol (PDP)

A packet transfer protocol in wireless GPRS (General Packet Radio Services) and HSDPA (High-speed Downlink Packet Access) networks.

PDP

Packet Data Protocol (PDP) Context

In UMTS (Universal Mobile Telecommunications System) and GPRS (General Packet Radio Service), the record that specifies UE access to an external packet-switched network.

Personal Identification Number (PIN)

An optional security feature in mobile devices used for identifying a user. PIN is a numeric code which must be entered each time a mobile device is started.

PIN

Personal Unblocking Key (PUK)

A digit sequence required in 3GPP mobile phones to unlock a SIM that has disabled itself after an in correct personal identification number has been entered multiple times.

PUK

Power Saving Mode (PSM)

A feature introduced in 3GPP Release 12 to improve battery life of IoT (Internet of Things) devices by minimizing energy consumption. The device stays dormant during the PSM window.

PSM

Pre-shared Key (PSK)

A password authentication method, a string of text, expected before a username and password to establish a secured connection. Also known as a "shared secret".

PSK

Privacy Enhanced Mail (PEM)

A public key certificate defined in the X.509 cryptography standard and used to privately transmit email.

PEM

Protocol Configuration Options (PCO)

An element of NAS message used for transferring parameters between the UE and the P-GW (Packet Data Network Gateway).

PCO

Protocol Data Unit (PDU)

Information transferred as a single unit between peer entities of a computer network and containing control and address information or data. PDU mode is one of the two ways of sending and receiving SMS messages.

PDU

PS Mode of Operation

A UE mode of operation. The UE registers only to EPS services.

Public Land Mobile Network (PLMN)

A network that provides land mobile telecommunications services to the public. A PLMN is identified by the MCC and MNC.

PLMN

Quality of Service (QoS)

The measured overall performance of a service, such as a telephony or computer network, or a cloud computing service.

QoS

Reference Signal Received Power (RSRP)

The average power level received from a single reference signal in an LTE (Long-term Evolution) network.

RSRP

RP-SMMA

A message sent by the User Equipment to relay a notification to the network that the mobile has memory available to receive one or more short messages.

Serial Number (SNR)

A unique six-digit number part of the IMEI code identifying each equipment within each Type Allocation Code (TAC).

SNR

Signal-to-Noise Ratio (SNR)

The level of signal power compared to the level of noise power, often expressed in decibels (dB).

SNR

Software Version Number (SVN)

Part of the IMEI code identifying the revision of the software installed on a mobile device.

SVN

Subscriber Identity Module (SIM)

A card used in UE containing data for subscriber identification.

SIM

System in Package (SiP)

A number of integrated circuits, often from different technologies, enclosed in a single module that performs as a system or subsystem.

SiP

Terminal Adapter (TA)

A device that connects a UE to a communications network. In mobile networks, the terminal adapter is used by the terminal equipment to access the mobile termination using AT commands.

TA

Terminal Equipment (TE)

Communications equipment at either end of a communications link, used to permit the stations involved to accomplish the mission for which the link was established.

TE

Tracking Area Code (TAC)

A unique code used to identify a tracking area within a particular network.

TAC

Tracking Area Update (TAU)

A procedure initiated by the UE when moving to a new tracking area in the LTE (Long-term Evolution) system.

TAU

Type Allocation Code (TAC)

The initial eight-digit part of an IMEI code used for identifying the model of a mobile phone.

TAC

Universal Integrated Circuit Card (UICC)

A new generation SIM used in UE for ensuring the integrity and security of personal data.

UICC

Universal Subscriber Identity Module (USIM)

A card used in UE containing data for subscriber identification.

USIM

User Equipment (UE)

Any device used by an end-user to communicate. The UE consists of the Mobile Equipment (ME) and the Universal Integrated Circuit Card (UICC).

UE