Glossary and Definition of Terms in TETRA

 

Issue 3 February 2006

ACELP

Algebraic Codebook Excited Linear Prediction method for low bit rate voice coding and decoding

ADPCM

Adaptive Differential Pulse Code Modulation

AES

Advanced Encryption Standard

AI

Air Interface

Air Interface encryption

Encryption on the air interface – the vulnerable link between base station and terminal

Air Interface protocol

The protocol, which defines the way in which signals are transmitted between radio terminals and the system infrastructure

AKD

Authentication Key Distribution

AL

Ambience Listening, Supplementary Service in TETRA to allow an authorised user, e.g. a dispatcher, to remotely switch the MS into transmit mode and monitor its environment without the intervention of the MS user

AMR

Adaptive Multi-Rate, Codec, one which in the low-error environments operates at a higher bit rate to give higher quality speech, whilst in higher-error environments, when higher speech quality cannot be sustained, the codec reduces its operational bit rate.

Analysis-by-synthesis

Speech coding technique which aims to minimise the mean-squared error between the input analogue speech and its synthesised version

ANSI

American National Standards Institute, www.ansi.org

APCO

Association of Police Communications Officers

API

Application Programming Interface, published software interface specification for designing applications on top of some lower layer software

ARIB

Association of Radio Industries and Businesses, Japanese radio standardisation body, www.arib.or.jp/english/

ATSI

Alias TETRA Subscriber Identity

Authentication

A security mechanism in TETRA, based on the challenge -response between the MS and the infrastructure, in order to ensure the legitimacy of each party

AVL

Automatic Vehicle Location, service or application showing location of a vehicle, either in terms of its geographical coordinates or by its location on a map

BER

Bit Error Rate

BS

Base Station

C/N

Carrier/Noise power ratio

Carrier

A radio channel which could carry one or more communication channels

CCK

Common Cipher Key, used to protect group downlink calls in class 3 systems

CDMA

Code Division Multiple Access

CEPT

European Conference of Postal and Telecommunications Administrations (Conference Européenne des Administration des postes et des telecommunications), www.cept.org, see also www.ero.dk

Channel surveillance

Monitoring of signal strength against a pre-determined threshold level in order to decide if DMO may be allowed

CMCE

Circuit Mode Control Entity

CMD

Circuit Mode Data, a method for data transmission where a continuous connection is required for the lifetime of the session to transmit all the data in a complete burst as opposed to Packet Data where the data can be split into sections or ‘packets’

CMIS/P

Common Management Information System/Protocol

CNM

Central Network Management

CNMI

Central Network Management Interface

CODEC

also Codec – Combined Coder and Decoder

COMSEC

Communications Security

Conventional

Non-trunked radio communication where communication resources (RF channels and base station sites) are manually selected.

CORBA

Common Object Request Broker

Covert Secret, hidden

Usually refers to type of equipment, e.g. covert terminals, for use with agencies involved in surveillance and under-cover operations

CRC

Cyclic Redundancy Code (Block coding)

CVO

Clear Voice Override, switching from encrypted to clear voice

DCK

Derived Cipher Key, key produced as a result of authentication, used for uplink and one to one messages

DDI

Direct Dial In

DES

Digital Encryption Standard

DGNA

Dynamic Group Number Assignment, Supplementary Service defined in the TETRA standards which is used for dynamic management (creation and dissolution) of user talkgroups

Dialling

Exchange mechanism between User and Terminal; the act of selecting the called party

Discreet Listening

TETRA Supplementary Service enabling an authorised user like a dispatcher to covertly (secretly) monitor the calls in progress

DM Repeater

A radio device designed to retransmit each call and thus increase the operational area of Direct Mode terminals

DM Direct Mode

(DM or DMO), the facility for TETRA terminals to communicate directly with each other without using TETRA infrastructure

DMO

Direct Mode Operation, the facility for TETRA terminals to communicate directly with each other without using TETRA infrastructure

DMR

Digital Mobile Radio, an ETSI standard being developed for low tier conventional PMR applications.

Downlink

Transmissions from the base station to a radio terminal.

DQPSK

Differential Quaternary Phase Shift Keying

DSS 1

Digital Subscriber Signalling 1

E2E

End to End Encryption – Encryption of the total communication link (from one end to the other) without intermediate decryption, required for maximum security

ECC

Electronic Communications Committee, the telecommunications committee of CEPT, producing Decisions, Recommendations and Reports to harmonise European regulation, see www.ero.dk

EN

European Norm, a standard like TETRA approved through national voting procedure

Encryption key

A pseudorandom number used “to seed” a key-stream generator

Encryption

Method for coding/ scrambling the information (voice or data) so that it cannot be understood or deciphered without special equipment or software

EPT

ETSI Project TETRA (now changed to Technical Committee (TC) TETRA)

ERC

Earlier name for ECC, documents available via www.ero.dk

ERO

European Radiocommunications Office www.ero.dk

Es/No

Energy per symbol / Noise power spectral density

ETS

European Telecommunication Standard (ETSI document prefix)

ETS

European Telecommunication Standard, name of standards (earlier) produced by the European Telecommunications Standards Institute (ETSI) available via www.etsi.org

ETSI

European Telecommunications Standards Institute, www.etsi.org

EU

European Union, www.europa.eu.int

Excitation generator

Generates pulses of variable amplitudes (and maybe positions) to represent the actions of the lungs and vocal chords

FCC

Federal Communications Commission, (U.S. telecommunications regulator www.fcc.gov )

FDMA

Frequency Division Multiple Access

FEC

Forward Error Correction (Convolutional coding)

Free-running

A device not requiring any human intervention or control in order to function (e.g. free running DM repeater).

Frequency Efficiency DMO

A variant of DMO protocol that uses all four timeslots, thus enabling two conversations on a single carrier

FSSN

Fleet Specific Short Number, one of numbering mechanisms in TETRA

Gateway

A device which interfaces TETRA network with other private or public telecommunications networks, e.g. PSTN, ISDN

GCK

Group Cipher Key, a key used (in conjunction with CCK) to give crypto group separation between groups

GGSN

Gateway GPRS Support Node

GoS

Grade of Service, used to specify the level of access on a radio network.

GPS

Global Positioning System

GPRS

General Packet Radio Service

GTSI

Group TETRA Subscriber Identity

GW

Gateway

HTML

HyperText Mark-up Language

IDEA

International Data Encryption Algorithm

I/F

Interface

IEC

International Electro-technical Commission

IMSI

Individual Mobile Subscriber Identity

Infrastructure

Base stations, switches, links, and various management equipments – all forming the network of equipments that enable mobile radio terminals to operate over a particular geographical area

IOP

Interoperability (of TETRA equipment)

IP

Internet Protocol

IPR

Intellectual Property Rights

ISCTI

Istituto Superiore delle Comunicazioni e tecnologie dell’Informazione, the current certification body for TETRA IOP

ISDN

Integrated Services Digital Network

ISI

Inter-System Interface, open interface standard used to connect two TETRA networks together

ISO

International Standards Organisation

ITSI

Individual TETRA Subscriber Identity

ITU

International Telecommunications Union

ITU-T

International Telecommunications Union-Telecomms

KMC

Key Management Centres, an entity for remotely loading keys to user terminals

Keystream

Pseudorandom data derived from KSG, used to mix with plain text data to produce encrypted data stream

KSG

Key stream generator: produces key stream from inputs of encryption key and synchronisation vectors fed into the encryption algorithm

LAN

Local Area Network

Late Entry

TETRA Supplementary Service which allows a user who has, for example, just switched his/her MS or has finished another call, to join a call in progress between the members of the group he/she is also a member

Lawful Interception

Facility for telecommunications networks like TETRA to be monitored and calls intercepted by government agencies

LNM

Local Network Management

LPC

Linear Predictive Coding

LS

Line Station, a fixed, wireline user terminal, as distinct from a mobile radio terminal, connected to a TETRA network, providing services and facilities available to a mobile user but without the need to be in the operational range of the system

LSI

Line Station Interface

MAC

Medium Access Control

Master DMO terminal/radio

The radio that initiates a DMO conversation and, in the absence of the synchronisation signal from the infrastructure, is acting as a control of the synchronisation timing

MCC

Mobile Country Code, (part of TETRA Number Identity)

ME

Members Enquiry, consultation process in TETRA interoperability specification work

MELPe

Mixed Excitation Linear Predictive, enhanced, the voice codec type adopted by NATO.

MGCK

Modified Group Cipher key, the key used for downlink group calls when GCKs are used. Formed from GCK modified by CCK

MII

Ministry of Information Industry (of the Peoples Republic of China) www.mii.gov.cn

MM

Mobility Management

MMI

Man-Machine-Interface

MNC

Mobile Network Code, (part of TETRA Number Identity)

MOPS

Million Operations Per second

MOS

Mean Opinion Score

MPT1327

Analogue trunking standard defined by UK DTI

MS

Mobile Stations are TETRA radio terminals, including hand-held, mobile and fixed ones

MS-PD

Multislot Packet Data, IP data service using multiple timeslots

MTBF

Mean Time Between Failure

MTTR

Mean Time To Repair

NATO

North Atlantic Treaty Organisation, www.nato.int

NMS

Network Management Subsystem

Number

Decimal digits dialled by the user, decimal representation of air-interface addresses as seen by the user i.e. user visible number

OTAR

Over The Air Re-keying. TETRA facility which allows for change of the encryption keys in the terminals to be done remotely over the air

PAMR

Public Access Mobile Radio

PCM

Pulse Code Modulation

PCN

Personal Communication Network

PD

Packet (Mode) Data, a mode of data transmission where data message is split into small ‘chunks’ or packets, transmitted packet-by-packet to the end destination (without a need for dedicated connection in between, as for circuit data), and assembled again in the correct order

PDN

Public Data Network

PDO

Packet Data Optimised, another variant of the TETRA standards set originally developed, which was not taken up by the market, largely because of its marginal advantage in terms of efficiency of packet-data communications when compared to V+D TETRA combined with a significant disadvantage of not offering the voice service

PEI

Peripheral Equipment Interface, standard interface defined in TETRA for connecting a data terminal to a TETRA radio terminal

PMR

Private Mobile Radio

Portable Radio

An older term for a hand-held radio

PPP

Point to Point Protocol

Priority

A service that in case of system congestion offers one or more levels of “call queue jumping”, to those users who are allocated it, on the basis that their communication needs or requests are deemed to be more important. The highest priority call is an Emergency call.

PSS 1

Private integrated Signalling System No. 1

PSTN

Public Switched Telephone Network

QAM

Quadrature Amplitude Modulation, scheme used in TETRA Release 2 for the TETRA Enhanced Data Service (TEDS)

QoS

Quality of Service

Roaming

Facility for offering an MS a service inside a visiting network, i.e. not its own home network

SAR

Specific Absorption Rate

SAP

Service Access Point

SCK

Static Cipher Key, used for protecting Direct mode transmissions where no authentication is possible, for class 2 systems and as a fallback key for use on base stations disconnected from the SwMI

SCN

Switching Control Node

SDS

Short Data Service

SDS

Short Data Service, a service in TETRA standards to deliver short data messages between user terminals. A message is composed of a number of characters and/or numerals, up to a pre-determined maximum

SFPG

Security and Fraud Prevention Group

Secret key (k)

The unique key embedded securely in the terminal, which is used for authentication

SIM

Subscriber Identity Module: A module used for storing personalization information of the user that can be moved from one terminal to another

Slave DMO terminal/radio

The receiving participant radio in a DMO conversation.

SNDCP

Sub Network Dependent Convergence Protocol

SNMP

Simple Network Management Protocol

SSI

Short Subscriber Identity, part of TETRA Subscriber Identity

STANAG

Standardisation Agreement [NATO]

Standard DMO

Direct Mode Operation using two out of the four timeslots available in a frame (one for uplink and other for downlink), thus enabling a single conversation on the carrier

Status Messages

Words or concise phrases selected from a pre-determined list that is resident in the terminal, which are transmitted as a simple code reference, and then de-coded by the receiving device and displayed as the word message, e.g. “At the scene”

Status Service

mechanism to deliver short messages between user terminals in compact form by transferring only an integer number with textual interpretation provided by the terminals, e.g. 09 could be interpreted as ‘off-watch’, and 08 as “at the scene”.

SwMI

Switching and Management Infrastructure

TC

Technical Committee, an ETSI body formed to develop standards such as TETRA

TCP

Transmission Control Protocol

TCP/IP

Terminal Control Protocol/ Internet Protocol

TDMA

Time Division Multiple Access

TDMA

Time Division Multiple Access, a technology for delivering digital wireless service that works by dividing a radio frequency into time slots and then allocating slots to multiple calls. In this way, a single frequency can support multiple, simultaneous, communication channels.

TEA1/2/3/4

TETRA Encryption Algorithm(s) 1,2,3 and 4

TEK

Traffic Encryption Key End to end keys used to protect the user traffic payload

Temporary/permanent disabling

The process by which the network disables terminals which have been reported as lost or stolen or have fallen into unauthorised hands.

Terminal

also radio terminal or a mobile radio terminal or a TETRA mobile station (MS) – a hand-held, mobile of fixed radio unit connected to the TETRA system via air interface

TETRA MoU Association

The TETRA MoU Association founded in 1994 to support promotion of ETSI TETRA standard worldwide, now known as the TETRA Association

TETRA V+D

TETRA Voice + Data, the suite of TETRA standards normally referred to as “TETRA”

TETRA

Terrestrial Trunked Radio, the ETSI standard for digital trunked radio communications (earlier known as Trans-European Trunked Radio and before that MDTRS Mobile Digital Trunked Radio System)

TIA

Telecommunications Industry Association, a U.S. standardisation body, www.tiaonline.org

TIP

TETRA Interoperability Profile, a test specification produced under the TETRA Association for testing TETRA equipment from different suppliers

TM

Trunked Mode

TMN

Telecommunications Management Network

TMO

abbreviation standing in for Trunked Mode Operation, as distinct from DMO, direct mode operation

TNP 1

TETRA Network Protocol 1

Trunked Radio Communications

A computer controlled communications system, which allocates communication channel for a call (either voice or data) from a “common pool” of available channels, and at the end of that call, returns them to the same “pool” to be reallocated for another call.

TS

Time Slot

TSI

TETRA Subscriber Identity

TTR

TETRA Association Technical Report, publication series for TETRA interoperability specifications

UDP

User Datagram Protocol

UMTS

Universal Mobile Radio System

Uplink

Connection from radio terminal to the base station

V. 24

ITU-T Recommendation V. 24

V. 28

ITU-T Recommendation V. 28

V+D

Voice plus Data

VATSI

Alias TETRA Subscriber Identity allocated in the visiting Network

VGTSs

Group TETRA Subscriber Identity(ies) allocated in the visiting Network

Vocoder

Voice coder

WAP

Wireless Application Protocol, open protocol for delivery of Internet content over radio path in a condensed format

WG

Working Group, usually a small team formed as part of an ETSI TC to produce a specific ETSI deliverable

WML

Wireless Mark-up Language

X.121

ITU Recommendation – Numbering Plan for Data Networks

X.25

ITU-T Recommendation X. 25

X.75

ITU-T Recommendation X. 75

 

A downloadable PDF version of the Glossary of Terms and Definitions used in TETRA can be provided by ‘clicking’ Glossary of Terms & Definitions