Glossary/Links
Glossary
A
Active Termination
One or more voltage regulators to terminate voltage (ensures a uniform signal level over the entire bus).
ActiveX-Controls
(or ActiveX Control Elements).
A set of interfaces that accesses Windows resources: small additional modules, called controls, that can be embedded in a program. The module concept was standardized by Microsoft and dubbed ActiveX (for example, there is a calendar element that provides programs standard calendar functions, eliminating the need of programming them on your own).
ADR
(Astra Digital Radio).
Transmission procedure for digital radio stations that have been broadcasting since 1995 via ASTRA satellites. It is based on the data compression procedure Musicam / MPEG-1. The data rate is 192 Kbit/s (including error correction 256 Kbit/s). In addition, 9.6 Kbit/s are used as overhead to transmit Radio Data Signals (RDS), conditional access (access control for Pay Radio) and other signaling data.
ADSL
(Asymmetric Digital Subscriber Line).
"Asymmetric" form of DSL, in which data flows Downstream at a rate of >10 Mbit/s and Upstream at > 800 Kbit/s. Due to the different data rates involved, this form of data transmission is referred to as "asymmetric.".
Advanced Television Enhancement Forum
ATVEF.
Aliasing
Distortion of video images (or other analog information) as a result of digitalizing analog information or processing information by digital means with an insufficiently small sampling rate (Sampling). To reproduce the information properly, the sampling rate must be at least twice as large as the resolution of the original.
Active Box
Loudspeaker box with built-in power amplifier or output amplifier (also for loudspeakers with separate amplifiers for high, middle and bass frequencies).
@
The commercial a - also referred to as the "at" sign. It has become a symbol recognized by the world as a separator in e-mail addresses.
ANSI
(American National Standards Institute).
Anti-aliasing
Suppressing the effects of Aliasing by filtering out rough, 'step-like' edges or by smoothing the edges by mixing colors to form transitions (interpolation).
API
(Application Programming Interface).
Software interface for user programs that allows programs to access the operating system or user interface resources.
APS
(Automatic Programming System).
Automatically assigns all receivable television stations to the TV's preset positions when the TV is switched on for the first time.
Architecture
In terms of data processing or information technology: general term for the structure of all parts of a computer system (hardware and software).
AIR
(Area Infra Red).
A proposed method of extending the IrDA standard. An increase in the angle of departure to 120° often eliminates the need for direct visual contact between the infrared transmitter and receiver. At the same time the range increases to approx. 8 metres. At such large distances, however, the maximum data rate is reduced from 4 Mbit/s to 250 Kbit/s.
ASCII
(American Standard Code for Information Interchange).
Internationally used code for letters of the alphabet, digits and special characters: a data format that allows text to be exchanged between computers which have different operating systems. The original standard ASCII character set is based on a 7-bit code and has no special characters (ß, ö. ä. etc.) or formatting styles (bold, italics etc.). The introduction of an 8-bit code expanded the ASCII character set to include a number of special characters and block graphics symbols.
ASPI
(Advanced SCSI Programming Interface).
Standard to develop SCSI drivers. The ASPI manager ensures that all devices connected to the SCSI controller work properly.
Assistant
(also referred to as "Expert" or "Wizard").
A tool designed to help users create programs (e.g. databases).
Atapi
(AT-Bus Attachment Packet Interface).
Interface for AT-Bus hard disk but also for CD-ROM drives or CD recorders that 'understand' the IDE controller.
ATVEF
(Advanced Television Enhancement Forum)
Consortium of hardware manufacturers and program vendors interested in creating a single standard from various procedures of interconnecting TV and Internet under the name ATVEF (Advanced Television Enhancement Forum). ATVEF is also aimed at the home-network market, particularly because the interfaces defined in the standard proposals call for controlling much more than TVs and computers.
Audiovision
Combination of sounds and images.
B
Backbone
High-speed cable - for example, within the Internet- that interconnects subnetworks. Online service providers or Internet providers are connected either directly or indirectly to a backbone.
Back-end
The "side" of a client/server program that supplies data (typically a database server (Front-End).
Bandwidth
The maximum, usable frequency range (measured in Hertz) available for transmitting data: often - although not quite correct - used as a synonym for the data transmission rate.
Bandwidth on Demand
A component in the DECT-MMAP standard that provides the required channel capacity - dependent on the current service and data load.
BCI
(BatiBUS Club International).
The BatiBUS is a bus system developed jointly by Merlin-Gerin, Airelec, EDF and Landis & Gyr to control heating systems, air conditioning, lighting and other functions in buildings. More than 80 participants in the field of building services management systems now belong to the BCI, which was formed in 1998 and is a member of the Konnex Association (KNX).
BLER
(Block Error Rate).
Number of data blocks, contained in one or more errors at the lowest level of error correction.
Bluetooth
The Bluetooth consortium (www.bluetooth.com) introduced the open Bluetooth standard 1.0. in 1999 led by the founding companies Ericsson, Nokia, Toshiba, IBM, and Intel.
A Bluetooth system comprises the following: radio components (transmitter/ receiver, the associated electronics), a link controller (to set up communications, managing connections etc.), a link manager (to communicate with the terminal in which the Bluetooth module has been installed). Bluetooth devices automatically recognise one another and create an interconnected network. The data is transferred from one adapter to another at a carrier frequency of 2.4 GHz (ISM band). The signals do not have any preferred direction and therefore, in principle, can be received by any appliance. Bluetooth operates with spread spectrum modulation, combined with frequency hopping (1600 sudden frequency changes per second). Between 2.402 GHz and 2.480 GHz there are 79 useable hopping frequencies, each separated by 1 MHz. A distinctive ID plus data encoding ensures that units can only communicate with each other if this has been "authorised".
The maximum data rate is in the region of 750 kBit/s and the range is restricted to ten metres. However, the standard also allows for one hundred metres with increased transmitter power. The operating system has to satisfy certain requirements in order to fully exploit all the Bluetooth functions. These include the ability to recognise Bluetooth hardware, establish connections and perform secure data transmission. The first products to be equipped with Bluetooth hardware and software were introduced at the end of 1999. It is expected that by 2005 almost one billion units like these utilising Bluetooth technology will be in circulation.
Bookmark
A bookmark allows the user to find previously accessed pages on the Web by saving the relevant addresses (URLs). WWW addresses can be saved with any Browser currently available.
BPI
(Bits per inch).
Describes the data density on magnetic media in bits per inch.
BPS
(Bits per Second).
A unit to measure the data transmission rate, for example, the transmission path of a modem. The fastest modems operate today at 56,000 BPS. An ASCII letter consists of 8 bits; theoretically speaking, a 56-K modem can transfer 7,000 characters (nearly 2.5 pages of standard letter-size pages) per second.
Browser
Software/user graphic interface for navigating, searching/surfing in the information pages of online services such as the World Wide Web. Browsers allow the user to access and display pages or documents that were written in Hypertext Markup Language (HTML). A browser also interprets mouse clicks on a Link.
Building automation
(home automation, residential system technology, residential wiring technology).
Describes the sum of all automating measures in buildings (including rented housing and private homes). Building automation makes it possible to control and regulate technical systems to ensure efficiency, primary energy savings, productivity and comfort.
C
Cache
A small, intermediate memory area to exchange or transfer data, for example, between the hard disk and central processing units. A cache accelerates hard disk access.
CALL
(terms from CTI):
Alternate call: allows the user to switch back and forth between two calls. Answer call: allows the user to take a call. Clear call: allows the user to terminate a call. Clear connection: allows the user to terminate an individual call. This service is required if the user wants to terminate a call to only one conference participant within a telephone conference. Consultation call: allows the user to consult (call) a third party while the second party is still on the line. Conference call: allows the user to converse with several parties on one line. The maximum number of conference members are limited by the PBX. Deflect call: forwarding an incoming call without having to actually answer the call. Make call: enables the user to set up a call. Make predictive call: a user program transfers one or more call numbers to the PBX. The PBX sets up the connection automatically but does not place the call to the extension until the party called has lifted the receiver. This function is only useful if the extension is in an ACD group, otherwise there is no guarantee that the call made will be answered. Monitor device: A PBX is requested to forward all events at a particular extension (device) to a file server. A caller with the number XXX-XXXX is assigned to the extension. Retrieve call: a caller has parked his call and terminates his current call. Retrieve call makes it possible to return to the first caller. Transfer call: allows the user to forward a call to another phone.
CASS
(Conditional Access Sub-System).
System of access authorization to (digital) TV and radio services that can only be descrambled (Descrambling), i.e. viewed or heard for certain user groups or if a service fee has been paid.
CCIR
(Comité Consultatif Internationale des Radiocommunications).
International consultative committee for radio and TV standards.
CCITT
(Comité Consultatif Internationale de Telegraphie et Telephonie).
An international consultative committee for international telecommunication protocol standards.
CD-DA
(CompactDisk-DigitalAudio).
Standard for audio CDs (defined in the Red Book drafted by Philips and Sony).
CEBus
(Consumer Electronics Bus).
Communications standard for home networks developed by the Electronics Industry Association (EIA) and the Consumer Electronics Manufacturer Association (CEMA).
Chip
Term for complex, integrated circuits that can contain several hundred thousands semi-conductor circuits (transistor/diodes etc.). By creating structures as small as one thousandth of a millimeter, higher levels of integration can be achieved.
Client/Server
Databases in a network are often administered by a central location by a server. Client software installed on the user's computer retrieves required data from the server.
Common Interface
An interface specified by DVB, e.g. as PCMCIA interface in Set-Top boxes to conncect a Conditional Access Module. This enables the user to add a decoder module to a generic set-top box with a common interface to receive the services/programs offered by a Pay-TV provider.
Conditional Access
In the framework of the European project DVB, a European transmission standard, DVB/MPEG-2, was passed. There are various systems (e.g. Irdeto, Beta, Conax, Cryptoworks, Seca, Syster Digital, Viaccess) used in Europe for the additional encoding required by Pay-TV channels (Conditional Access, CASS).
Constraints
Logical rules stored in a database. These rules check certain conditions at the table level, for example, whether a particular range of values was violated for numerical fields.
Cookies
Small files that are sent from a Web site to the user's Web browser and then stored on the user's hard disk. When the user returns to the Web site, the Web browser sends the information back to this site. This allows the user, for example, to display individualized elements that appear as soon as the URL is selected.
CRC
Cyclical Redundancy Check.
Checksum to correct errors that occur during data transmission.
CTI
(Computer-Telefon-Integration).
Describes the integration of telephones and computers. This enables solutions that go far beyond the limitations of a standard telephone. A classic example is using a telephone in combination with a PC database. CALL. (call commands).
Cyberspace
A term coined by William Gibson in his novel Neuromancer published in 1984. Today, it describes digital communications and Internet data space.
D
DAB
(Digital Audio Broadcasting).
System for digital terrestrial transmission of radio and multimedia data services. The MUSICAM system is used for data compression - from 1.411 Mbit/s to 192 Kbit/s.
Data Dictionary
Area of memory in which all information on a database and the accompanying programs are stored and managed. This includes information on tables, triggers, constraints, relations and indices.
Database
A term with several meanings: refers to a DBMS (Database Management System) as well as a file that contains, for example, customer addresses or other data. A database can combine several Tables into one file. Often only one table is allowed per database file for PC databases. In this case, the user can still create a link to other tables from various files (Referential integrity).
Data throughput
(Net data rate)
Transmission rate of the actual user data (excluding redundant data for error correction or data to delimit individual data blocks, e.g. Header). Specified in cps (characters per second).
Data header
Data structure at the beginning of a data packet Header.
Data packet
Data is generally transmitted within networks in the form of data packets. These packets contain the Header, the actual data (user data) and redundant data (CRC) for error correction on the receiving end.
Data rate
(also referred to as the 'data transfer rate').
This indicates the quantity of data transferred per unit of time in bit/s (bits per second).
Data record
Combines all the data for a specific table entry into a logical entity. Using a file-card box as an analogy, a record would be the equivalent of one file card.
DECT
(Digital Enhanced Cordless Telecommunication).
The cordless telephone represents the most common application of DECT standards. Wireless, digital communication DECT-MMAP operating at ISDN speed (64 Kbit/s) or faster is growing in significance. The effective radiated power specified for DECT of 250 mW provides an effective range of up to 50m in buildings and 300m outdoors. The voice signal is 32 Kbit/s. Germany uses the 1.9 GHz band, whereas other frequencies between 1 an 10 GHz, commonly between 1.5 and 3.6 GHz, are also used. The access method used by DECT known as TDMA (Time Division Multiple Access, time multiplex) allows up to 100,000 simultaneous users in a single cell.
DECT-MMAP
(DECT-Multimedia Access Profile).
A further development of the DECT standard as a "virtual cable" for mobile data devices; typically used for wireless Internet or Intranet access within the transmission range of the base station with data rates of up to 2 Mbit/s. The most important DECT-MMAP features include Service Negotiation, Dynamic Resource Management and Bandwidth on Demand.
Descrambling
(also decryption).
The reconstruction of encrypted TV programs. Usually a chip or module in a television set or peripheral device (decoder/descrambler). Pay-TV, Encryption,
Digital Video Broadcasting
DVB.
DiSEqC
(Digital Satellite Equipment Control).
System to control satellite receiver equipment. Conventional satellite equipment uses a 14/18 volt switching voltage to switch between polarization levels (horizontal or vertical). An additional 22-kHz frequency on the input voltage line signals the direction of the satellite antenna to specific orbit positions. In contrast, DiSEqC uses a universal control concept, since the 22-kHz signal not only switches equipment on and off but also samples frequencies. This allows a number of commands (including polarization switching) to be transmitted within the DiSEqC system. DiSEqC level 2 also features bi-directional communication. Thus, the satellite receiver sends commands to the peripheral components capable of logging on to the receiver: Plug & Play in satellite receiver technology.
Domain
In an Internet address, the domain names separated by dots are listed according to the protocol and service (e.g. "http://www"). An example is "ehome-berlin" (sub-domain) and "de" (top-level-domain). The top-level domain can contain a country code ("de" for Germany) or an abbreviation indicating the type of server (for example, com for commercial companies, org for organizations or edu for universities).
Domotik
Widespread industry solution designed to connect Bosch products (security, telecommunications, household appliances, heating systems, etc.) by means of an integrated residential wiring system. All electrically controlled devices are networked via the European Installation Bus (EIB) and controlled by a multimedia PC. Domotik can also be operated with the HomeAssistant multimedia program used for entering the various functions. HomeAssistant runs on standard multimedia PCs. The user-friendly graphic interface is to a large extent self-explanatory.
Download
Information (e.g. PDF files) or programs can be copied from a server (e.g. from the Internet) to the computer's hard disk or other data media. Common examples of downloaded data include drivers for hardware components or updates for software applications.
Downstream
The flow of data from server to client or from supplier/provider to subscriber/customer. Opposite of upstream.
Dropout
Error (on the magnetic coating of a magnetic tape or on other magnetic media) caused by dirt or surface damage. Dropouts can cause - depending on their size and severity - read errors or data loss.
DSL
(Digital Subscript Line).
General description (also referred to as "xDSL") for high-speed, broadband data transmission over copper wires (i.e. "twisted pair" cables), ADSL, HDSL.
DVB
(Digital Video Broadcasting).
Initially conceived as the European Launching Group (ELG) in 1991, the DVB project was founded in 1993. It comprises nearly 180 companies, institutions and organizations, equipment manufacturers, TV and radio stations, network providers, research institutions and authorities from 23 countries. "The objective of the DVB, a project financed solely from membership dues without significant subsidies, is the shared and coordinated development of systems and standards in order to make digital television in Europe possible by means of satellite, cable and terrestrial broadcasting (German Platform for HDTV and New Television Systems). Although DVB was originally set up as a European project, a number of companies from Japan, South Korea, Canada and the USA have since joined. DVB can be used for more than digital TV and radio broadcasting. This technology can be applied as a generic "data highway" offering transfer rates of up to 36 Mbit/s. As a result, there have been proposals to rename the system Digital Versatile Broadcasting instead of Digital Video Broadcasting. DVB encompasses the following standards:
DVB-S
System for satellite transmission with a 11/12 GHz bandwidth; it can be configured for various transponder bandwidths and transfer rates. The type of modulation is a four-phase shifting (QPSK, Quadrature Phase Shift Keying): at a constant amplitude, the modulated signal can assume one of four phase conditions of which each can transmit 2 bits of information (given a bandwidth efficiency of 2 Bit/s/Hs).
DVB-C
A standard compatible to DVB-S to distribute digital programs or services in a cable network. In order to convert the data transmitted from satellites to a channel-compatible 8 MHz bandwidth, QPSK must be transcoded into 64-QAM (Quadrature Amplitude Modulation with a bandwidth efficiency of [64 = 26] 6 Bit/s/Hz).
DVB-CS
A DVB-C or DVB-S adapted standard for cable or satellite-supported reception of DVB signals via community antenna systems.
DVB-T
Standard for terrestrial television: this transmission procedure uses a bandwidth efficiency comparable to DVB-C for 7-8 MHz terrestrial channels and is based on a COFDM system (Coded Orthogonal Frequency Division Multiplex). In this multi-carrier procedure, the channel spectrum is divided into several thousand subcarriers each of which are modulated with a part of the data stream.
DVB-MS
(Digital Multipoint Video Distribution System / MVDS)
uses microwaves for the terrestrial transmission of a larger number of TV channels directly to the audience. The microwaves are bundled and broadcast to receiver antennas that are positioned in the 'visible area' of the transmitter antenna. Although they pertain to terrestrial broadcasting, the DVB-MS specifications are based on those for DVB-S. That is why DVB-MS signals of standard DVB satellite receivers can be received via small rooftop antennas, but a corresponding MVDS frequency converter is used instead of the LNCs (Low Noise Converter).
DVB-MC
specification for MVDS (Microwave Multipoint Distribution Systems) in the frequency range below 10 GHz. The procedure that is also used on the ground is based on the standards defined for digital channel transmissions (DVB-C) and thus uses similarly equipped receivers/decoders. (DVB-MS and DVB-MC are also referred to as 'specifications for wireless broadband cabling').
DVB-SI
The Service Information System is designed to transmit data within the transport data stream. It is used for the self-configuration of the DVB decoder (set-top box), to design the user interface and to identify programs and services.
DVB-TXT
DVB specification to monitor Teletext (in special data packets).
DVB-CI
DVB 'Common Interface' - common interface for Conditional Access and other programs.
DVB-Subtitling
Tools for subtitles and displaying the graphics.
DVB-RCC
Specification for interaction channels (forward and backward channels) in broadband cable networks.
DVB-RTC
specification for interaction channels (backward channels) via telephone and ISDN.
DVB-NIP
network-independent protocols for interactivity (protocols that permit communication in form of a data stream).
DVB-IPN
Gateways from DVB to the telecom world
DVB developments
Further specifications and procedures are in preparation or being developed for data radio via DVB, synchronization of single-frequency-networks, interfaces between the DVB world and ATM or SDH networks, Digital Satellite News Gathering (DSNG) based on DVB, bi-directional communication in GGA and terrestrial networks, networking DVB terminal equipment, integration of HDTV and DVB.
Dynamic Resource Management
frequency-economic adaptation of the channel bandwidth to the current traffic load DECT-MMAP.
E
ECC
(Error Correction Code).
Redundant data that helps detect errors and eliminate them through recalculation. Hardware error correction for hard disks that takes place while the data is being transferred. ECC, On the fly.
ECMA
(European Computer Manufacteres Assoiation).
Association of computer manufacturers with the goal of defining common standards.
EDO-RAM
('Extended Data Out' RAM)
Fast computer memory.
EHS
European Home System.
EIB
European Installation Bus.
EIBA
(European Installations Bus Association).
The EIB-Association, is a widespread manufacturer association dedicated to establishing the EIB standard. Over 100 manufacturers and more than 8,000 licensers throughout Europe offer nearly 5,000 EIB components.
E-IDE
(Enhanced Integrated Drive Electronics).
Advanced development of the IDE standard offering higher data transfer rates and support for newer drives.
e-Mail
Electronic messages that can be quickly sent throughout the world via Internet or other networks. E-mail is one of the most frequently used applications on the Internet. In addition to text, multimedia data can be sent as an "attachment."
ESPRIT
European Strategic Program for Research and Development of Information Technology.
Ethernet
Technology for local networks based on the CSMA/CD protocol. In conjunction with IEEE 802.3, data rates of up to 10 Mbit/s can be achieved. The new IEEE standard 802.3ae slated for ratification by 2002 allows for data rates up to 10 Gbit/s.
European Home System
(EHS)
EHS was created under the auspices of the EU project ESPRIT (European Strategic Program for Research and Development of Information Technology). It uses electrical wiring as the installation bus and offers a data throughput of up to 2.4 Kbit/s. A separate two-wired cable can also be used instead of an electrical cable. This increases the potential data throughput to a max. of 48 Kbit/s. EHS and EIB are to be united into a common standard.
European Installation Bus
(EIB)
Network technology for residential wiring. EIB is designed for two-wire cable only. EIB versions for electrical cables as well as wireless systems for radio and infrared - as a functional prototype - have recently become available. The Siemens "Instabus" complies with the guidelines of the EIB standard as well as Domotik developed by Bosch. The version EIB.net can also use normal data networks in accordance with IEEE 802.2 with transfer rates of up to Ethernet 10 Mbit/s. The extension EIB.net 'i' allows forwarding, for example via the normal IP router and thus the EIB connection via the Internet. Maximum EIB data transfer rate is 9.6 Kbit/s.
Eutelsat
(European Telkommunikation Satellite Organisation)
A European agency founded in Paris in 1977 to manage satellite communication services.
Extranet
Segment of the Intranet which can be accessed by authorized third parties (e.g. customers or suppliers). It uses Internet technology to establish communications between various company locations.
F
FAQ
(Frequently Asked Questions, "häufig gestellte Fragen"). Many Homepages and nearly all Newsgroups offer FAQ lists to answer questions frequently asked by users. To save time, it is often sufficient to refer to the list of FAQs to determine whether specific questions have already been answered.
Fast-SCSI
Transmission protocol compliant with SCSI-2 that allows data transmission of up to 10 Mbyte/s on a 8-bit bus.
FAT
(File allocation table) [Data medium].
The data table at the beginning of a partition used in operating systems such as DOS and Windows 95/98. The data table stores the information on where files are located on the disk.
Field
The smallest unit in a Record. Each field has a specific data type which contains, for example, text, dates, currencies etc.
File allocation table
FAT.
Firewall
Protects local networks from unauthorized access by intruders on the Internet.
FireWire
IEEE 1394.
Firmware
Commands stored in a ROM chip to control the hard disk. This data can usually be updated (flashing the ROM).
Frame
Frames make it possible to divide the Browser window into several sections and independently configure and control their contents. Thus, a fixed menu can be shown in one frame while scrolling text, images or animations can be displayed in another.
Free-TV
TV programs that are not scrambled and can be received free of charge. Free-TV is the opposite of 'Pay-TV'. In Germany, all analog stations - with the exception of 'Premiere' - are free-TV stations. In the past few years, most digital TV stations have also become Free-TV stations. As of early 1998, 34 channels were offered via the Astra satellite alone. These included broadcasts in English (CNN International, Travel TV, Cartoon Network), French (arte, TV5, Fashion TV), Spanish (Andalucía TV, TV Catalunya Internacional), Dutch (Wereldomroep TV, Cartoon Network), Italian (RAI uno), Polish (Atomic TV, Shopping TV) and Arabic (RTM, ESC 1).
Front-End
refers to a part of a program that allows user uses to access the database (see counterpart Back-end).
Full-duplex
Transmission protocol for the simultaneous transfer of data and signals in both directions.
G
GIF
(Graphic Interchange Format)
H
HAVi
(Home Audio-Video Interoperatibility). The goal of the HAVi consortiums (Grundig, Hitachi, Matsushita Panasonic, Philips, Sharp, Sony, Thomson und Toshiba) is the development of a home network architecture for the (consumer) electronics and multimedia industries. Philips represents the eight companies as a primary contact for licensing issues. According to the HAVi version 1.0b standards (can be downloaded as a PDF file from www.havi.org), user programs are capable of detecting and controlling HAVi-compatible equipment of different manufacturers. These programs can also control individual components within various systems independent of their physical location. The HAVi standards refer to a IEEE 1394-supported, digital AV-environment. The key specifications include components used for exchanging messages and events via IEEE1394, the registration and detection of device capabilities via the network and the management of digital AV streams and devices. Available features include a security system for virus protection, a component that supports functions such as pre-programmed (audio/video/data) recording as well as standard programming interfaces for controlling equipment functions.
HDSL
(High data rate DSL)
Transmission procedure capable of a transmission rate of 1,544 ->Kbit/s (T1) or with 2,048 ->Kbit/s (E1) with pulse-code modulation via dual copper wires.
HDTV
(High Density TeleVision).
High-resolution television (i.e. doubled horizontal and vertical resolution).
Header
Contains information about the type and/or meaning and/or structure of the subsequent data packet. Since the header forms the beginning of a data packet, it can also be used to mark the end of the previous data structure.
HiperLAN
(High Performance Radio Local Area Network, High Performance Radio Mobility in LANs).
(High Performance Radio Local Area Network, High Performance Radio Mobility in LANs).
The European ETSI standard for wire-less local networks. Based on the assumption that wire-lessLAN will expand wired LANs or to some extent replace them, the HiperLAN specification is based on existing LAN hierarchies. A similar standard (IEEE 802.11) has also been specified in the USA. HiperLAN Type 1 specifies a wire-less Ethernet with data rates of approx. 20Mbit/s in the 5 GHz frequency range. The HiperLAN Type 2 is a European standard for broadband radio communication with a limited range (up to approx. 100 metres).
Data rates of up to approx. 54 Mbit/s have been attained. The system operates on frequencies in the 5 GHz range. Typical application scenario: wire-less communication within company buildings (business environment) and the creation of wire-less networks consisting of consumer electronics equipment or computers and peripherals in private homes (home environment) for the transmission of multimedia applications (audio, video; text, data).
The intention is to operate HiperLAN2 together with the mobile radiotelephony standard GSM as a WAN (Wide Area Network) and with Bluetooth as a PAN (Personal Area Network). HiperLAN supports the transmission of packets of data through several stations as well as the transmission of time-critical and also of asynchronous, non time-critical packets of data. HiperLAN-compatible equipment operates in the frequency range of 5.15 GHz to 5.3 GHz. In the future there are also plans to make use of the carrier frequency range between 17.1 GHz and 17.3 GHz.
Home Automation
Building automation.
Home-Banking
Online banking, for example, enabling balances to be checked or transfers to be made, at any time of day or night.
Homepage
Starting page, i.e. page 1 of a Web site (WWW). It usually contains a table of contents and links to other areas or pages on the site.
Home Phoneline Networking Alliance
Consortium promoting the use of telephone lines for data transfers of up to 10 megabits per second without restricting parallel telephone usage (members: AMD, Compaq, 3COM, IBM, Intel and Lucent).
HomeRF
A wire-less local network making use of two protocols: DECT for four speech channels and IEEE 802.11 for data.
Home-Shopping
A service that enables users to shop online from home, browse catalogues, compare products from various suppliers on the screen and subsequently to order them by clicking on a mouse or by telephone.
HomeWay
Multimedia cabling system offered by Corning for apartments, houses and home-offices. The system requires only one cable and a universal wall receptacle for telephone, fax, PC, TV, home automation and multimedia programs. The multimedia cabling system consists of a control center, a broadband cable and a standard wall socket.
All external wiring is connected to the control center. A broadband cable networks all rooms, and the wall socket provides connections for multimedia terminal devices. In terms of design, the sockets are tailored to the various switch programs. Their modular structure ensures that all services are available at any point in the residence. The inserts can be easily replaced if the socket is to be used in another way, for example, for a cable TV connection in another room. An integrated component of HomeWay is home automation based on the already available Instabus EIB (European Instabus). HomeWay also meets the specifications recommended by major providers including ASTRA, Deutsche Telekom and property management .
HTML
Abbreviation for "Hypertext Markup Language" - the language of the World Wide Web. HTML makes it possible for documents to appear virtually identical on all computer systems regardless of the software and hardware used. A voluntary consortium (W3) regularly proposes new standards to maintain this compatibility.
HTTP
(Hyper Text Transfer Protocol)
The Protocol regulates the transmission of hypertext files on the Internet. HTTP is the foundation to transmit HTML pages on the Web.
Hyperband
In the service channel network, the frequency used for distributing TV stations (300 - 470 MHz). It is the range of choice for digital transmissions according to DVB-C.
I
IEEE
(Institute of Electrical and Electronic Engeneers).
IEEE 1394
The IEEE standard for high speed data transmission on a local cable network (LAN). This standard is also used for home networks (HAVi). The data rate is 100, 200 or 400 Mbit/s, depending on the design. Originally developed by Apple, the P-1394 bus technology became the industry standard in 1995 as IEEE 1394/1995 - also known as "Firewire". In 1997 Sony introduced its "i.Link" logo as the designation for standardised IEEE-1394 interfaces.
IEEE 802.11
The IEEE standard for a local radio network (wire-lessLAN).
IEEE 802.11b defines a local radio network operating in the 2.4-GHz frequency range with a data rate of 11 Mbit/s and can be used as a cable-less system for interconnecting various items of equipment and, for example, for providing internet access for several portable computers within a radio range of up to 100 m. The new IEEE 802.11a standard is intended to provide a maximum data rate of 54 Mbit/s in the 5-GHz carrier frequency range.
IES
Integrated Reception System.
IMode
This system has already been introduced in Japan and is now available in Germany too, by E-Plus. It enables particular internet content to be shown on the displays of specially designed mobile phones. iMode uses the programming language cHTML (Compact HTML), a subset of HTML, which is used for programming web pages
Infranet
Communication structure for networking equipment in the household or in other applications such as petrol stations, restaurants, medicinal technology or agriculture (a supplement to Internet and Intranet).
Integrated Reception System
(IRS)
With the structure of the IES - promoted by the satellite operator ASTRA and, for example, implemented by WISI - existing distributor and communication structures (cable, terrestrial systems, telephone) can be supplemented through community Sat-reception. The accompanying wall socket combines antennas and telephone connections.
Intelligent Home
(Intelligent Home, Smart Home, Digital Home, Networked House).
House or apartment with a cabled or wireless intelligent network used to control signals for Building automation or transmit multimedia signals. The forerunners of today's modern concepts: Professor Ken Sakamura's Tron house in Tokyo in the 80's and Chriet Titulaer's Huis van de Toekomst in Rosmalen (Holland).
Intelsat
(International Telecommunications Satellite Organisation)
An organization of over 150 member countries promoting intercontinental telecommunications via satellite.
Interleave / Interleaving
1. Multi-level, interleaved storage of user data to simplify error correction. Interleaving is also used for digital television (DVB) as a means of splitting code. Bytes from a defined number of successive data packets are selected in memory in such a way that the successive bytes originate from various data packets. Through this interleaving, which is reversed in the receiver, transmission errors that have corrupted a longer section of the digital data stream are parsed into single errors that are easier to correct.
2. Arranging the sectors in a similar way on a hard disk cylinder.
Internet
Worldwide conglomeration of data networks. Initially intended for military use, the Internet was increasingly used for exchanging research data among universities and institutes. Today, online service providers and network providers have made the Internet available to everyone.
Intranet
Internal (corporate) network using Internet technology such as TCP/IP.
IP
(Internet Protokol), TCP/IP
IP adress
Address of a single computer on the Internet. The IP address consists of four numbers from 0 to 255, each separated by dots (example: 123.27.1.155). In order to make this system more practical for users, IP addresses are converted into alphanumeric names.
ISDN
(Integrated Service Digital Network).
A digital network that integrates several different services.
IRC
(Internet Relay Chat).
A communication platform that allows users to synchronously communicate (chat) with other IRC users online via keyboard.
IRC-Op
IRC operators who administrate the IRC servers on an international level. These operators have access to additional commands unavailable to normal users.
IRD
(Integrated Receiver/Decoder).
Receiver/Decoder unit for digital data or TV services. IRD describes the same device internationally known as "Set-Top box", "Digital Decoder".
IrDA
A wire-less, point-to-point, infrared-based connection. This attains a maximum data rate of 4 Mbit/s with a maximum range of 1.5 m. To enable communication between units they must be within sight of one another and the angle of sight along the centre axis may not exceed 15°.
ISAPI
(Internet Server API).
Programming interface for Internet server programs that use the Microsoft Internet Information Server (MIIS) in conjunction with Windows NT.
ISM-Band
(Industrial, Science, Medical).
A frequency range of 2400-2483.5 MHz, which is reserved for industrial, scientific and medical applications. Also used for short distance radio networks (Wire-lessLAN, Bluetooth).
J
Java
Full network capable, object oriented and platform-independent programming language used to create Web-independent programs (developed by Sun Microsystems).
Javascript
Programming language (not the same as Java) which expands the possibilities of HTML. JavaScript allows the user to integrate functions such as graphic effects, animated menus, ticker tapes etc. in Web pages (developed by Netscape).
JINI
(Java Intelligent Network Infrastructure).
Sun Microsystems introduced JINI technology in the summer of 1998. It is based on Java and can "spontaneously" network connected devices. In other words, devices that are dynamically connected to the network are immediately detected throughout the entire network.
JINI regulates the communication between computers and other devices in the network and allows peripherals to be connected to the network without special configurations and used immediately. The self-identifying devices transmit their technical specifications and eliminate the need for "manual" driver selection. In contrast to Ethernet systems, JINI automatically allocates resources.
JPEG
(Joint Photographic Experts Group).
One of the most popular graphic formats. The JPEG format frequently used in digital photography compresses large or color-intensive pictures to a fraction of their original size. This reduces storage requirements and file transfer time (i.e. on the Internet).
K
Konnex
(Konnex Association, abbreviated: KNX).
An association of equipment manufacturers, service providers and other companies and institutions with an interest in home automation/building service management systems. Konnex links the resources of EIB (European Installation Bus), EHSA (European Home Systems Association) and BCI (Batibus Club International).
L
Lag
The delay caused by high traffic congestion or other overloading between IRC servers or Internet provider sites resulting in slow communications.
Link
In the World Wide Web, a link allows the user to branch from one Web page to another. Links are usually displayed as underlined text on HTML pages. Clicking on these links makes it possible to "surf" the World Wide Web.
LNS
(LonWorks Network Services).
LNS allows the user to integrate LON systems into the Internet and Ethernet installations via gateways.
Local Control Network
(LCN)
An installation bus developed by Issendorff GmbH for residential and functional buildings. Conventional installation elements such as switches, pushbuttons, sensors etc. are replaced or supplemented by "intelligent" modules. All modules in the building are connected to an additional wire in the installation cable (actually a 4-wire electrical cable that uses an added wire as a data channel). The data transfer rate is 9.6 Kbit/s.
LON
(Local Operating Network)
LonWorks
LonWorks
The field bus system originally developed by Echelon Corporation (Palo Alto, California) for production control. According to company information, it is the field bus system most widely used in the world for Building automation (reference installations in Germany: Reichstag Building and Debis administration offices in Berlin). This technology was developed in 1988 and launched on the German market in 1991.
In a LON (Local Operating Network), every bus participant, or "network node", has its own microprocessor or "neuron processor." The separate network nodes work independently and do not communicate with other nodes until it becomes necessary. A LON can be operated with two-wire cables, coaxial cable, electrical cables or as a wireless system. Depending on the transmission path, the data rate is 10 Kbit/s (electrical cable) up to a theoretical maximum value of 1.2 Mbit/s (1,200,000 bits per second).
According to press reports, integration into known data networks - for example, through cooperation with the Internet specialist Cisco - is the most widespread configuration. Using LNS (LonWorks Network Services), LON systems can be integrated via gateways into Ethernet installations and the Internet.
LonWorks Network Services
LNS.
Lookup-Service
(also known as "spontaneous networking" because each device is detected immediately as soon as it is connected to the network). A component of the JINI system architecture that registers every active JINI device in the network together with its technical characteristics in a table and makes it available to authorized users (example: a handheld computer that has been registered in the look-up service detects available printers, free memory space on a hard disk in a desktop computer, or an Internet connection).
M
Message
Messages or Private Messages refers to messages sent to one or more IRC participants. These messages can only be read by the recipient and the sender.
Micro-payments
[Electronic Commerce].
Payments in the penny range. Because of their "micro" value, the transaction costs must be considerably lower than, for example, credit card payments.
Microwaves
Frequencies in the range above 3 GHz (Gigahertz = billion Hertz). Microwaves can also be used to distribute digital TV services and are sometimes referred to as "wireless cable."
MPEG
(Motion Picture Experts Group).
A common workgroup - Working Group 11 (WG11), also known as the international MPEG laboratory - of the International Standards Organization (ISO) and the International Electrotechnical Commission (IEC). MPEG was founded in 1988 by over one hundred companies to negotiate proposals and define standards in specific expert groups (requirement or system groups).
MR Head
(Magnetoresistive heads).
Write/Read head in hard disks that can supply a stronger signal level when reading data from the disks due to a magneto-resistive element.
Multi Channel Feed
Data compression, encoding and modulation processes are optimized for minimum bandwidths in Digital Video Broadcasting (DVB) resulting in a relatively large number of transmission channels. This is why a program can be transmitted through several channels by several cameras simultaneously. Viewers can view the event from a selected camera angle (and not necessarily from the perspective of the director). Typical applications include simultaneous broadcasts of Formula 1 racing events from inside different vehicles, from a helicopter or from the pit lanes. Symbols displayed on the screen show the viewer which button to press and which perspective will be shown.
Multimedia Home Plattform
(MHP)
The MHP software package is the open, technical solution for all new multimedia programs and services within the framework of the DVB standard (digital television). MHP connects radios, the Internet, TVs and computers. Essentially, a standard system for all services. With MHP, the DVB project has a uniform standard for the software interface (Application Programming Interface, API) of universally applicable DVB receivers. By implementing the standardized software interface (DVB-J) based on the program language Java, all services and programs can be implemented in set-top boxes in the future. As an interface available to all program and service providers, MHP opens the door to manufacturing receivers that are compatible with all current and future standards. MHP will be implemented in DVB receivers and multimedia PCs.
MUSICAM
(Masking pattern adapted universal subband integrated coding and multiplexing).
Complies with MPEG-1 Audio, Layer II. It reduces the data rate of audio signals from 1,411 Mbit/s (audio CD) to 192 Kbit/s.
N
Newsgroups
The "blackboards" of the Internet. Includes thousands of public information and discussion forums sorted according to topic. Participants can read and submit messages.
NICAM
A transmission mode employed in various countries for two digital audio signals (stereo or bi-language) in the analog TV channel.
NTSC
(National Television System Committee).
US TV signal with 60 Hz vertical frequency, a 4:3 screen format and a resolution of 767 x 575 pixels.
NVoD
(Near Video on Demand).
A TV program broadcast in, for example, 20 minute intervals on additional channels. Audiences can then watch a program practically at any time starting within the 20 minute time frame.
O
ODBC
(Open Database Connectivity). Interface defined by Microsoft for database systems. With an ODBC driver installed on a PC, the user can access other formats such as dBase, Paradox or Access.
OOP
Abbreviation for object-oriented programming. This program philosophy was made popular through Smalltalk, Object Pascal and C++.
Operating system
Software that controls and checks a computer's basic functions and logical devices. An operating system manages, for example, the resources and processes, input/output controls, file system and the user interface.
OSD
(On Screen Display).
A screen menu providing user instructions and simplifying operation.
P
PALplus
A system introduced in 1994 that is backward compatible to the PAL standard system for analog transmission of TV programs in the 16:9 Widescreen format aspect ratio. Coordinated by Germany's ZDF network, PALplus was developed by a consortium of industrial companies, TV stations and research institutes. On conventional screens (4:3 format), PALplus programs appear in the letterbox format with black strips along the upper and lower edges of the screen.
PASC
(Precision Adaptive Subband Coding).
Similar to MUSICAM. Coding and data compression process for audio signals. It offers a data rate of 384 Kbit/s and is used for DCC (Digital Compact Cassettes).
Pay-TV
Subscription television. Audio and video signals can only be received (unscrambled) after a fee has been paid to the program provider Encryption.
PCMCIA
(Personal Computer Memory Card Industry Association).
Originally designed as a memory expansion card for laptop computers, this interface is used today for miniature modems or for digital TV descrambling systems.
PIP
(Picture In Picture = 'Bild im Bild')
An additional picture displayed within the TV picture. This system is used to simultaneously view a second TV channel or monitor the image by a remote camera.
PLC
(Powerline Communications Forum).
A consortium founded in 1997 by members of the telecommunications industry and energy suppliers. This group tests applications and services supplied to homes via electrical cables to determine their feasibility and efficiency PowerLine, MediaFusion.
Plug-Ins
Small, supplemental programs that can be downloaded free of charge from the Internet. Plug-ins add new functions to the Web browser making it possible, for example, to view new multimedia information on the Web.
Plug & Play
Procedure to automatically configure computer expansion devices or cards.
PowerLine
Systems that use the electrical network for data transfer PLC, MediaFusion.
PRML
(Partial Response Maximum Likelihood).
Digital procedure to interpret the data stored as analog information on magnetic data media.
Protocol
Rules that define how data is transmitted through "data highways", in online networks and between components within a computer.
Proxy server
[Internet] Proxy servers function similarly to Cache memory. They increase "surfing speed" by caching pages previously visited on remote computers. If a Web page is to be opened, the proxy server will first check if the page is available on the hard disk. If so, the page is loaded by the proxy server. Proxy servers reduce the traffic on the data highway.
Pulse width modulation
PWM.
PWM
Pulse width modulation. PWM is a standard means of encoding data read by a laser beam from optical media (CD, DVD).
Q
QAM
Quadrature Amplitude Modulation. Digital modulation procedure. QAM is used, for example, for digital TV broadcasting via broadband cable.
QPSK
(Quadrature Phase Shift Keying).
Digital modulation procedure. QPSK is used, for example, for TV broadcasting via satellite.
R
Regulating authority
[Telecommunications]. Until December 31st, 1997, the Federal Ministry for Post and Telecommunications (BMPT) regulated the telecommunication market in Germany. This ministry regulated charges, defined legal standards and issued licenses. The ministry was disbanded in January 1998 and replaced by the regulating authority for post and telecommunications.
Referential integrity
For databases, referential integrity in its simplest form means that when a record is deleted by a main table, all related subordinate records in other tables will also be automatically deleted.
Relational database
A database which does not have a pre-defined link structure. This allows the user to create new relationships between tables dynamically, i.e. during the course of operation. (For example, link customer names with invoices using the customer ID number).
Residential system technology, residential wiring technology
Building automation.
Resource Manager
A component of the HAVi system capable of managing a number of operations. It resolves conflicts between devices, coordinates the programming of scheduled events (such as timer recordings on a digital recorder) and monitors the network to determine if reserved devices are still in place.
Runtime module
Allows the user to execute a database program without requiring the entire database development system required to create the program.
S
Sampling
Scanning analog signals in which samples of the current amplitude are taken at the sampling frequency and digitized. The quality of the digital signal depends on the sampling frequency (twice as high as the frequency of the digitized analog signal).
Scrambling
Encryption of TV images to make them unrecognizable. In reference to Pay TV, programs that are scrambled can only be received by subscribers who have agreed to pay a fee for the program and have a descrambling unit (decoder) connected to their TVs.
SCSI
(Small Computer System Interface).
Standardized interface for connecting peripheral devices to a PC.
Search engine
Databases containing information on documents available in the World Wide Web, i.e. the "reference works" or "indices" of the Internet. Search engines are created manually or automatically by computers.
SGRAM
(Synchronous Graphics RAM).
High-speed video memory for video signals.
Server
Computer in a network that makes resources available to connected computers (clients), programs, storage space, printers etc. (Client/Server, Video-Server).
Service Negotiation
A component in the DECT-MMAP standard to negotiate the minimum and maximum data rates for a particular service.
SES
(Société Européenne des Satellites). Company that operates Astra satellites.
SET
(Secure Electronic Transaction).
Payments are encrypted and sent via a (trusted) third party - a bank for example - checked, and customer identity verified
Shareware
Programs that can be copied for testing purposes. Users who decide to use the program are required to register the software and pay a fee to the author. Shareware programs can often be used without restriction - based on the presumption that users are honest - sometimes, however, they are limited in function or expire after a certain period of time.
SIG
Bluetooth Special Interest Group, with over 1,500 member companies and organizations.
Simulcrypt
Several CA systems (CASS) are transmitted simultaneously in a program packet. A decoder with one CA system suffices for reception. Example: a Seca or Viaccess decoder is required for the French ABsatPacket.
SMPTE
(Society of Motion Picture an Television Engineers).
SMPTE has developed a time code under the same name for controlling the synchronization of images and sounds.
SoD
(Service on Demand). VoD.
SQL
(Structured Query Language).
A universal query language for databases; it is used primarily for databases in banks or in similar multi-user systems.
Symbol
A data block consisting of a defined number of bits (the most well known example of a symbol is a byte consisting of 8 bits).
T
Table
Combines identical records in columns (fields) and rows (records).
TAPI
Abbreviation for "Telephony Application Programming Interface", the Windows telephony interface developed by Microsoft, CTI.
TCP/IP
(Transmission Control Protocol/Intemet Protocol).
Technical basis to transmit data on the Internet. This Protocol divides the contents of a Web page into small packets and sends them along different paths, if necessary, to the receiver where TCP/IP then reassembles the packets in their original order.
Transaction
A transaction ensures that any modification to a database is carried out either completely, i.e. for all records, or not at all.
Transponder
[Satellite transmission technology].
Combination of a receiver that receives signals from a terrestrial station (uplink) and a transmitter that beams down the signals as a satellite TV program to the earth (downlink). The term is a combination of transmitter and responder.
U
Ultra-SCSI
Extension of Fast-SCSI that allows a data rate of up to 20 Mbyte/s by doubling the clock frequency.
Ultra-Wide-SCSI
Extension of Wide-SCSI, that allows a data rate of up to 40 Mbyte/s by doubling the clock frequency.
Universal LNB
[Satellite transmission technology].
A receiver unit located in the focal point of a parabolic antenna (dish-shaped or satellite antenna). LNB (Low Noise Block Converter) is also used to describe an LNC (Low Noise Converter). In the LNB, the signals received from a satellite are converted into a lower frequency range before they are forwarded per cable to the satellite receiver in or next to the TV set. The term 'Universal' indicates that the LNB can be used for both analog TV (10.7-11.7 GHz) and digital TV (11.7-12.75 GHz) frequencies.
Universal Plug and Play
(UPnP).
Windows 9x and Windows 2000 offer "Plug & Play" technology to automatically detect all compatible devices within a PC. "Universal Plug & Play" is designed to expand this technology to include devices in an (external) network. Once devices are connected to a network supporting Universal Plug and Play, they automatically configure themselves, which eliminates the need for set-up and configuration. UPnP detects the devices along with the relevant product characteristics including communication protocols. For example, a camera can automatically detect a printer in the network, determine its ability to print in color, and print a photo.
Universal Serial Bus (USB)
The Universal Serial Bus developed by Intel and based on a star topology can connect up to 127 devices on different levels to a PC and replaces earlier interface standards. Each device forms the end or point of a star. Direct communication between connected USB devices is not possible. Control is provided by a USB controller that functions as a host. The complicated process of reserving address ranges and interrupts has been eliminated. Only the USB controller requires an interrupt from the BIOS. Thanks to the hot-plugging function, any number of devices can be switched on, plugged into different sockets or removed while the PC is in operation. The USB host detects the change and renumbers the device addresses. Windows 98 is the first operating systems to fully support the Universal Serial Bus.
In version 1.1, the USB operates at a maximum data rate of up to 12 Mbit/s. Version USB 2.0 will offer data rates that are 20 times faster, i.e. 240 Mbits per second, and will be backward compatible. Devices are connected with a four-wire cable with standardized plugs that are polarized to prevent them from being plugged in the wrong direction. The cable can also supply current, if necessary, to connected peripheral devices. The devices are chained to the bus via passive hubs which can also be integrated into separate USB devices such as keyboards or monitors. The maximum cable length between hub and peripheral is five meters.
Intel introduced a USB system 2.0 early in the year 2000 that offers a maximum data rate of 480 Mbit/s - 40 times faster than version 1.1 (For more information, see: www.usb.org).
UPnP
Universal Plug and Play.
Upstream
The data flow from a client to a server or from a subscriber/customer to a provider; the opposite of Downstream.
URL
(Universal Resource Locator).
Address for Internet pages. A URL consists of a server name, possibly a directory name or full pathname, and the document title (example: www.ehome-berlin.de/index/main.html).
V
VESA
(Video Electronics Standards Association).
Video on Demand
VoD.
Video-Server
Hard disk storage for video signals with computer-controlled file management. In contrast to magnetic tape cassettes, this type of storage offers fast random access to specific scenes or images. In conjunction with Video on Demand (VoD), proposed video servers will provide storage capacity for hundreds, or possibly thousands, of video clips and films. Instead of Gigabytes, these storage capacities are being measured in Terabytes (1 Terabyte = 1024 Gigabyte).
visiomatic® Home System
The visiomatic® Home System provides unique functionality, while at the same time refusing to add superfluous gimmickry. The monitoring and control of home automation, security technology, entertainment electronics, communications technology, telematics and infotainment are provided on a single user interface which utilizes clear design and simple terms and symbols to make management of all of the technologies more simple. The base is an intelligent software with a large number of interfaces, while the general system comprises a powerful industrial controller which has been designed for around-the-clock operation 365 days a year.
visiPad®
The visiPad® displays are touch screens, design highlights, operating elements, televisions and telephones, all wrapped up in one device.
visiSoft
The visiSoft® is the intelligent core of the visiomatic® Home System. The ergonomic user interface of the software enables to operate intuitively all of the integrated functions without any previous knowledge.
VoD
Procedure in which TV programs can be directly accessed by a subscriber via a back channel of a video server. The transmission which requires special switching equipment with distributed structure and bi-directional channels from and to the subscriber is enabled after the payment has been made. Similar services are discussed, such as Audio on Demand, Software on Demand and others that are outlined under the heading: SoD (Service-on-Demand).
Voice mail
Similar to E-mail, voice mail is a message sent or received within a network as audio data.
VRAM
(Video Random Access Memory).
High-speed video memory.
VRML
(Virtual Reality Modeling Language).
A programming language to display 3-D spaces on the Internet. VRML allows the user to design virtual landscapes or 3-D games. Current browsers are capable of displaying such data. Numerous browser plug-ins offer 3-D functions.
W
Widescreen
TV screen format with an aspect ratio of 16:9 (width/height). This adapts to the perspective of human vision in which the horizontal range is wider than the vertical range. Widescreen images reduce eye strain, particularly for larger screen formats. From a technical standpoint, the 16:9 format can be implemented in conventional analog TVs (PALplus) as well as digital TVs (DVB).
Wi-Fi
(Wireless Fidelity).
The inofficial designation for wireless networks conforming to IEEE 802.11.
Wide-SCSI
Transmission protocol compliant with SCSI-2 that defines an extension of the bus width to 16 bit and thus requires special cables and plugs. Wide-SCSI is normally used together with Fast-SCSI and is capable of data transmission of up to 20 Mbyte/s.
WirelessLAN
(Wireless Local Area Network).
A (wireless) local radio network operating in the 2.4 GHz frequency range in accordance with the IEEE 802.11b standard, with a data rate of 11 Mbit/s, this is a system for interconnecting various items of equipment without the need for cables, providing internet access, for example, for several portable computers within a radio range of up to 100 m.
WRAM
Window-RAM. Special type of VRAM with high bandwidth used by Matrox, Number Nine and other video card manufacturers.
X
Xanadu
Bill Gates' networked home uses a variety of methods for electronic house control. According to press reports, the house has over one hundred PCs connected to thousands of sensors and activators used to regulate lighting, air and temperature. They also use chip cards to identify the whereabouts of people in each room. Once the person has been identified, their music and video preferences can be pre-selected.
Xpresso
A processor designed for the Java-Engine by Zucotto Systems. It is used for broadband access to handheld devices via an integrated Bluetooth connection. The Xpresso core is formed by Sun architecture (KVM, Kernel Virtual Machine) around which the proprietary data slice (service layer in Consumer Electronics) was programmed.
Y
Z