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Glossary of Telematics Terms

In this section of the website you will find a glossary of many of the terms used in the telematics industry.

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Second generation of mobile telephony systems using digital encoding. 2G networks support voice, low speed data communications, and short messaging services.


In mobile telephony, 2.5G protocols extend 2G systems to provide additional features such as packet-switched connections (GPRS) and enhanced data rate.


Third generation of mobile systems. Provide high-speed data transmission and supporting multimedia applications such as full-motion video, video-conferencing and Internet access.


Analogue refers to signals that can represent an infinite range of numbers, as opposed to digital which can only be distinct whole numbers. Analogue data often comes from measurements, like a sine wave. The sound a modem makes over the phone is analogue since it can be any of a number of different frequencies. The fixed-line networks usually transfer analogue data and fax. The GSM networks are Digital.


American Standard Code of Information Interchange. It uses 7 bits to represent all uppercase and lowercase characters, as well as numbers, punctuation marks, and other characters. ASCII often uses 8 bits in the form of bytes and ignores the first bit.

Automatic Crash Notification (ACN)

Vehicle onboard system designed to notify a designated call centre in the event of a significant collision, reporting the vehicle location, speed and severity of the crash, deployment of airbag(s) and other diagnostic information from onboard sensors (sometimes referred to as "Mayday systems"). An "Accelerometer" is often used to track the suddenness of the impact and activate notification when preset G-Force is achieved.

Automatic Vehicle Location (AVL)

The automated system and related technology of tracking vehicle locations. AVL systems utilise GPS technology coupled with wireless communication systems to provide a vast array of data to the home station and/or fleet operator. Also known as Telelocation in the European Union. Sometimes referred to as AVL GPS.


The difference between the upper and lower limits of a band. A range of radio, audio, or other frequencies. Since it is so limited, a modem must carefully change data into sounds that "fit" within this range. Similar to frequency spectrum. Bandwidth of a voice channel is 3000Hz-300Hz which equals 2700 Hz. Telephone lines have a bandwidth from 300 hertz to 3400 hertz.


A Binary digit. It is a number in base 2 (binary), which means that it can only be a 0 or a 1. It is used in the expression 'bits per second'. [See also byte].


Bits Per Second. The transmission speed of most modems is measured in baud or bps. Bps is literally the number of bits sent by the modem every second.


A group of 8 bits. It usually represents one character.


Wireless standard for short-range radio communications between a variety of devices such as PCs, headsets, printers, mobile phones, and PDA's. Range is dependent on power Class (class 1 = ~100m, Class 2 = ~10m, Class 3 = ~1m).


The receiver/transmitter a GSM phone connects to; the equivalent of the base station of a cordless phone. A cell can support a number of simultaneous calls.


A number that represents a larger group of numbers in order to check for errors in data transmission. It is commonly used when downloading a program, as well as in error control protocols. The checksum is the result of a mathematical equation, such as adding all the numbers in a block together (although it is usually more complex than that).


A group of important IC chips on a modem (or other computer peripheral) that are all made by the same manufacturer. While there are many companies that make modems, there are only a few that make the chips for them. Because the chip manufacturer is making the chips for many companies, they produce more chips, and the price of the chips is lower than if each company produced their own. This decreases the price of the modems on the market.


Compressor/DECompressor, the chip inside every digital GSM cellphone that allows the cellphone to transmit voice data at high efficiency and speed across the GSM cellular network. The CODEC will trip redundant voice data like when neither party is talking allowing more efficient use of scarce bandwidth.


Stands for Code Division Multiple Access, which is a mobile technology, operated in several countries including the USA and South Korea.


Container Tracking & Security: GPS and other technologies that enable the intermodal tracking of individual containers and integrity monitoring of transported goods including it’s quality (temperature, moisture etc) and it’s security via tamper detection.


Commercial Vehicle Telematics : Telematics installed in a commercial fleet as part of an overall fleet management GPS system.

Data Packet

Information about a vehicle or group of vehicles, or other non-voice data, transmitted via communication conduits (cellular, Internet, etc.) to the fleet management system computer.

Differencial GPS

using data from at least four (4) GPS signals, this method of GPS corrects for a designed random error to achieve a more precise location, usually within 2 meters. This system utilizes a fourth location signal from land based signal towers maintained by the US Coast Guard to enhance the accuracy of GPS for navigation on the waterways.


(Domain Name system) Name resolution software that lets users locate computers on a UNIX network or the internet (TCP/IP network) by domain name. The DNS server maintains a database of domain names (host names) and their corresponding IP addresses.

Dynamic IP Address

An IP address that is automatically assigned to a client station in a TCP/IP network, typically by a DHCP server. Network devices that serve multiple users, such as servers and printers, are usually assigned static IP addresses. (See static IP address).


Electrically Erasable Programmable Read-Only Memory.


Electronic Toll Collection: a technology that electronically debits the accounts of registered car owners for tolls that are due without requiring them to stop.


Fleet Management System: Vehicle telematics (GPS tracking and diagnostics, driver management, fuel and emissions management) for a company’s vehicle fleet.


Essentially the European version of GPS, this system is currently under development. It will ultimately consist of 21 to 28 satellites in a mid-Earth orbit (MEO) and between 3 and 8 satellites in geosynchronous (GEO) orbit, which may use signals from GPS.

General Packet Radio system (GPRS)

Packet switching technology where information is transmitted in short bursts of data over an IP-based network allows continuous connection to data networks in support of many kinds of applications, including messaging and rapid data transfer.


Using street address or block address data to determine the latitude and longitude of that address.


A GeoFence is a geographic boundary that can be defined for the purpose of monitoring an asset or vehicle. It could be used in conjunction with a vehicle security tracking system that records all entry and exit of assigned vehicles from GeoFence boundaries and can alert the system users when these "events" occur.


Is a shorter name for Geographic Information. Geographic information is created by manipulating geographic (or spatial) data (Geodata) in a computerised system. systems can include computers and networks, standards and protocols for data use and exchange between users within a range of different applications. Typical applications are land registration, hydrology, cadaster, land evaluation, planning or environmental observation.


Comes in many different forms, such as maps or images taken from the air or from space, i.e., remote sensing data. Geodata may be stored in a database, which may possibly have special extensions for storing, handling, and manipulating spatial data. Geoinformation is the useful output, produced by analysing data with a kind of computer program called a "geographic information system", or GIS. The environment in which a GIS operates (machines, people, networks) is called a "spatial information system", and is designed and created to respond to the strategic spatial information needs of people or organisations.

Geographic Information systems (GIS)

A combination of the geospatial data systems and software designed to support transportation routing and logistics, generally for a municipality or regional area.

Global Orbiting Navigation Satellite system (GLONASS)

A Russian space-based navigation system comparable to the American GPS system, GLONASS is comprised of 21 satellites in 3 orbital planes, with 3 on-orbit spares.

Global Positioning system (GPS)

A technology that uses signals and data from multiple satellites to determine a location anywhere on Earth. It is a radio positioning system which provides location information via satellite, enabling the accurate pinpointing of GPS equipped vehicles and other objects.


This stands for General Packet Radio Services. It is a GSM Packet Based bearer for the delivery of data services. With GPRS you only pay for the amount of information you download rather than the duration of the connection.


Stands for Global system for Mobile communications and is an international standard which allows you to use one phone and one number worldwide. GSM is a digital technology and therefore the call quality is of a very high standard, calls are always clear, and the network is very secure. GSM enables clients to cross international boundaries with just one phone number.


A unit of frequency, which equals cycles per second.


High Speed Datalink Packet Access, protocol used in so called 3G cellular networks.


The International Standards Organisation, the body responsible for setting world technical standards. It is based in Geneva, Switzerland.


International Telecommunications Union, based in Geneva, Switzerland.

Intelligent Transportation systems (ITS)

A general term for many technology systems used in highway, rail and other transit to improve mobility, reduce accidents, and improve transportation overall, i.e. electronic toll collection systems, synchronized traffic signals.


Global network of networks, using a common set of standards (e.g. the Internet Protocol), accessed by users with a computer via a service provider.

IP Internet Protocol

The packet data protocol used for routing and carriage of messages across the Internet and similar networks.


Internet Service Provider. A company that provides access to the Internet.

IP address

(Internet Protocol address) The address of a computer attached to a TCP/IP network. Every client and server station must have a unique IP address. Client workstations have either a permanent address or one that is dynamically set. IP addresses are written as four sets of numbers separated by periods; for example,



Local area network. A network allowing the interconnection and intercommunication of a group of computers on a single site, primarily for the sharing of resources and exchange of information (e.g. email).

Lone Worker Device

Soon to be a government requirement in some countries (i.e. Canada by 2007), One example of a lone worker device is an RFID-based handheld that will be required for workers that spend any time alone during the day. This device requires the lone worker to physically acknowledge ‘pings’ (vibrations or beeps) by pressing a button on the handheld every predefined interval. If that worker fails to respond to 2 or more pings, it communicates via RFID back to the telematics unit which sends a notification of the lone worker’s GPS co-ordinates. Emergency buttons are also available on lone worker devices.


Location Based Service: Information services accessible with mobile devices through the mobile network and utilizing the ability to make use of the location of the mobile device.


Light Commercial Vehicle : the formal term in the European Union for goods vehicles with a maximum allowed mass (MAM) of up to 3.5 tonnes. In general language, this kind of vehicle is usually called a van.


Less than Truck Load: the transportation of relatively small freight that is larger than the goods handled by parcel carriers and less than full truckload carriers.


Mobile Data Terminal: is a computerized device used to communicate with a central dispatch office. Mobile data terminals feature a screen on which to view information and a keyboard or keypad for entering information, and may be connected to various peripheral devices.


Mobile Resource Management systems are productivity enhancement software, hardware and services used to support the activities of mobile workers and include technologies such as AVL GPS, Internet, hosted software and wireless data networks.


Memorandum of Understanding, the GSM body that overseas GSM standards and implementation around the world. It comprises operators and some manufacturers.


The Navstar Global Positioning system (GPS) is a space-based constellation of orbiting satellites providing navigation data to military and civilian users all over the world. This system is maintained by the U.S. Military and provides the foundation for almost all commercial GPS systems in use in the United States.


Network Address Translation. This allows an organisation to present itself to the Internet with far fewer IP addresses than there are nodes on its internal network. The NAT technology, which is typically implemented in a router, converts the private IP addresses (such as in the range) of the node on the internal private network to one IP address or of several IP addresses for the public Internet. It changes the packet headers to the new address and keeps track of each session, so that when the packets come back from the Internet, it performs the reverse conversion to the IP address of the client machine. NAT also serves as a firewall by keeping internal addresses hidden from the outside world.



Personal Communication Services (PCS 1900 or GSM 1900). The North American GSM service operating on 1900 MHz as opposed to the European standard of 900 MHz.


Personal Navigation Device: A portable electronic product, which combines a positioning capability (such as GPS) and navigation functions. Also known as a PNA, a Personal Navigation Assistant.


The term that describes payment in advance for airtime.




Pay As You Drive: Telematic automobile insurance sometimes known as usage-based insurance whereby the costs of motor insurance are dependent upon vehicle usage, particularly distance traveled. Pay As You Drive™ is a trademark of Norwich Union in England and Progressive in the US.


Power Line Carrier – where power and communication share a single wire.


Power Line Carrier communications standard designed specifically for heavy duty vehicles. Uses the SAE J1587 standard.


Reverse - Geocoding

Using latitude and longitude data from the GPS receiver to determine the exact street address or block address.

Roam / Roaming

The ability to use networks overseas and cross geographical boundaries whilst using a single number and a single phone.

Serial Transmission

A method of transmitting data in which bits are sent sequentially.


Supply Chain Management is the process of planning, implementing and controlling the operations of the supply chain as efficiently as possible. Supply Chain Management spans all movement and storage of raw materials, work-in-process inventory, and finished goods from point-of-origin to point-of-consumption. Also known as Service Chain Management.


Subscriber Identity Module. This is a Smart Card installed in every GSM handset. Within the GSM application the three primary roles of the SIM are access control to the network (authentication & ciphering), service personalisation (SMS, advice of charge, etc.), network branding and advertising (graphics printed on SIM card). The new generation of Phase 2+ SIMs will enable services such as virtual cash, mobile banking, ticket reservations etc.


Short Message Service will display a pager-like 160 character message in the LCD panel on the phone. Your phone must support SMS.

Selective Availability

Prior to May 2000, the US military intentionally degraded the accuracy of GPS signal data for civil and commercial purposes as a protective measure. The Department of Defence retains the right to restrict signal accuracy in the interest of US national defence.

Static IP Address

A permanent IP address that is assigned to a node in a TCP/IP network. Servers and routers are usually assigned static IP addresses, while client stations are often assigned dynamic IP addresses from a DHCP server each time they come online. (See Dynamic IP address).

Telematics Service Provider

An organisation that provides a range of telematics services, including vehicle tracking, trailer tracking, mobile data and RFID


Or 'Telecoms' Conveyance over distance of speech, music and other sounds, visual images or signals by electric, magnetic or electromagnetic means.


Universal Mobile Telecommunications system, Protocol used in some so called 3G and 3.5G cellular networks.


Vehicle Area Network, where the telematics device acts as a Wi-Fi access point for laptops, PDA’s, etc. around the vehicle.


Voice over Internet Protocol. A technology that allows users to send calls using Internet Protocol, using either the public Internet or private IP networks.


Wide area network. A network allowing the interconnection and intercommunication of a group of computers over a long distance.

Wireless LAN or WiFi (Wireless Fidelity)

Short range wireless technologies using any type of 802.11 standard such as 802.11b or 802.11a. These technologies allow an over-the-air connection between a wireless client and a base station, or between two wireless clients.

Wireless Hot Spot

When a service vehicle is parked within 200m of their local garage, workstation, etc.. it makes sense to provide them an 802.11a/b/g “hot spot” that their telematics device connects to, giving them fast, free, and secure access to their local network removing the need to use the expensive cellular (or satellite) network. More and more companies are finding that the majority of the technician’s internet time is spent near their home location. If the telematics unit has Wi-Fi, wireless hot spots reduce unnecessary airtime charges.



Low power short-range wireless communication protocol, intended to be less expensive than Bluetooth.