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10/5/2009
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Business to business. A generic term relating principally to Internet-related services provided by one corporation for the use of other corporations or for communications between corporations.
Business to consumer. A generic term relating principally to Internet-related services provided by a corporation for use by individuals who are the end-consumers or for communicating to consumers.
In the early 1980s the telecommunications system of the USA was mainly in the hands of AT&T (American Telephone and Telegraph), then the world's largest company in terms of assets, employees and shareholders. The system was known as the Bell System after the bell-shaped trade mark symbol used for its operations. It was also colloquially known as 'Ma Bell' as it was omni-present, reliable and trusted. As part of an anti-trust settlement that AT&T reached with the Justice Department it disposed of its seven local operating companies in 1984 but retained the long-distance business plus Bell Laboratories and Western Electric. Part of Bell Labs became an R&D service organisation called Bellcore (later sold and trading as Telcordia) jointly owned by and serving the local operating companies. Most of the remainder of Bell Labs and Western Electric were subsequently to become Lucent Technologies. AT&T retaind the long-distance business.
The seven Regional Bell Operating Companies (RBOCs), each of which comprised more than one Bell Operating Company (BOC), were known as the Baby Bells and sometimes as the Seven Dwarves, as an allusion to Cinderella's helpers. They were Ameritech, Bell Atlantic, Bell South, Nynex, Pacific Bell, Southwestern Bell, US West. Many of these have subsequently merged with other companies or each other. The changes were a milestone in telecommunications history by changing the guiding philosophy of the new managements from being a utility with the prime objective of increasing telephone penetration to one of maximising profit. It set the scene for many other changes around the world ushering in a wave of de-regulation and competition and the privatisation of similar, but state-owned, organisations in other countries. See also Telco, privatisation, competition, de-regulation.
Strictly speaking this is an analogue term which defines the range of frequencies that can be conveyed over a communications channel. It is best understood in the context of radio frequencies where signals occupy a defined bandwidth out of a vast spectrum of frequencies.
It can be applied to the bearer medium or to the service. For instance an average length twisted-pair local-line can carry signals between 0 and more than 500 kHz whereas an end-to-end communications voice service over that pair is usually 0.3 - 3.4 kHz. Voice systems are therefore normally said to be narrowband, whereas the copper-pair is capable of much greater bandwidth.
The terms wideband and broadband are used to describe greater bandwidths but such terms are not well defined especially as they are mostly used nowadays to refer to digital systems. The use of bandwidth related to digital systems is an established convention but the term 'speed' is more correct - however the two have become inextricably confused. For instance it will be said that "broadband (or wideband) starts at speeds above XXXkbit/s" (where XXX changes over time depending on the technical capabilitites of the day).
This is a concept where the operator, or even user, can influence the amount of bandwidth available as required (more properly this is a variation in speed in a digital environment). This can be pre-determined through a booking system, be under customer control, or happen automatically in real-time. Pre-determined and temporary changes are not difficult to achieve, although administratively more complex. User-control provides a higher degree of complexity as the billing and network configuration aspects have to be controlled automatically. Real-time changes, such as an IP network narrowband voice call changing to a wideband call to download a video clip and then back again, provide even further degrees of complexity. A truly flexible network under user control remains in the holy grail category but progress continues to be made.
A term used in cellular wireless systems to cover the transmitting and receiving equipment and antenna that provides the link (air interface) to the customer device (invariably a mobile phone or PC/PDA). Sometimes more properly called the base transceiver station (BTS). A BTS will usually define a cell and be at or near the centre of it, with the size of the cell determined by the transmit power. It will have between 1 and 16 transceivers each of which represents a single RF channel.
The BSC monitors and controls several base stations (BTS) and may or may not be co-located with one of them. The BSC and BTS together form the base station subsystem (BSS).
This is a programming language that has been around since the early 1960s. It is, or was, relatively easy to learn for a beginner although with the passage of time the human desire for added complexity has resulted in several variants not all of which are compatible with each other. It was retrospectively said to stand for Beginners' All-purpose Symbolic Instruction Code.
Basic rate ISDN comprises two 64 kbit/s 'B' (bearer) channels and one 'D' (data) channel. Also known as basic rate access (BRA). See also Primary rate ISDN.
The number of times per second that a signal changes its value. The basic unit of a signal is the symbol and the Baud is the number of symbols per second. The Baud rate is the signalling rate but this is not necessarily the same as the bit rate. With a binary code the Baud rate and bit rate will be the same but not when coding systems are employed. For instance, a quaternary code will have 4-levels of transmission at half the binary symbol rate. That is, two bits are needed to express the four states, so the bit rate is twice the symbol (or Baud) rate. The Baud originated as a telegraphy term named after Emile Baudot (1845 - 1903) and was important in the days of Morse Code and teleprinters (including the Baudot 5 bit teleprinter code). It was designed for that period and is now rarely used in an era where symbols, bits and bytes dominate.
Bearer independent call-control (BICC)
As voice over IP became more important the ITU took the view that emulating existing services with a new protocol would not result in an identical service and that a reduction in services would not be acceptable to customers. However, the immediate needs of operators to relieve capacity with new and novel forms of networks led to work that would redefine the main signalling protocol for telephony networks, the ISDN User Part (ISUP) of Signalling System No 7 (SS7). The term the ITU coined for this was bearer-independent call control or BICC. Work started on ATM bearer versions with the aim of moving to IP bearers later. See also VoIP , SIP.
A type of telecommunications service that provides the capability for the transmission of signals between the two user to network interfaces. That is to say that the customer is free to make whatever use of the bearer channel in any desired way. Thus the higher layer functions (i.e. above ISO layer 3) are determined by the customer.
The area of billing is a specialised and important function within telecommunications OSS. In other industries billing is a lot simpler, and may be performed within enterprise resource planning (ERP) systems. The billing systems adopted depend on the billing approach of which there are many, including a separation of the ownership and operation of the network from the services offered to customers. The latter requires a network wholesaler to bill service providers for traffic over the network with any other services provided billed separately (see service provider and virtual service provider). Services can be usage based, subscription based, volume based or some combination. For example, private circuits (leased lines) are essentially a fixed price subscription based service independent of usage. Data services have a variety of approaches including pricing by bits (or Megabits) transferred. As a more detailed example, the functions performed in usage-based telephony billing include:
- Collection and pricing (or ‘rating’) of usage events
- Generation of customer bills. The charges for the bill arise from the usage events, setup and recurring charges associated with products, one-off charges, discounts, tax, etc.
- Formatting and despatch (by various means) of bills.
- Handling payments, adjustments and debt management.
See also usage mediation and volume-based billing.
Biometric methods automatically confirm the identity of a person using either a distinctive aspect of their appearance, for example a fingerprint or an iris pattern, or a unique action by that individual (such as a real-time electronically written signature or a spoken phrase). It meets the requirements of the third of the 3 level security mantra 'something you know, something you have and something you are or do'. Whilst biometric methods can replace the likes of passwords and keys whilst providing a higher security level they can contribute to even greater security as a part of a tiered approach.
A basic element of digital transmission. It stands for one binary digit - of which it is a contraction. There are two states: on or off, mark or space, 1 or 0 and numerous other ways of expressing it. The rate at which bits are transmitted is expressed in bits per second, or bit/s, but bps is used in North America. The information carried is related to the symbol rate or Baud. See also byte which is usually, but not always, 8 bits and is often used to express the capacity of storage media such as CD or DVD. Non-technical people sometimes get confused between bits and bytes, such as when downloading from the Internet where they forget to multiply the message showing the bytes/sec by eight to get the bits/sec. Also see Units and Symbols for various transmission hierarchies.
A measure of the quality of a circuit used for digital transmission expressed as the number of bits incorrectly received to the total number of bits received (e.g. 1 in 10^8).
The insertion of extra but redundant bits into a data stream to synchronise time-slots in switching operations. The presence of the stuffed bits is signalled to the receiver so that the stuffed bits can be removed to restore the original signal.
A technique invented and patented by British Telecom whereby a fibre is blown into a tube, typically in a cable, using the viscous drag on the surface of a specially packaged fibre.
A standard for a short-range wireless technology using the 2.4 Ghz ISM (industrial and scientific and medical) band. It uses a fast frequency hopping radio technique to change its operating frequency 1600 times a second. This enables it to carry on working in areas of high interference. It can support voice and or data at up to 723kbit/s.
See Future applications of Bluetooth, BTTJ, Vol 21 No3.
Bridges connect multiple similar Local Area Networks (LAN) to form a virtual single LAN. They are protocol independent and don't look at the data or change it in any way.
A term of variable meaning where the only consensus is that it is not narrowband - which in turn is usually taken to mean voice or low-rate data. Sometimes also known as wideband. The transition from narrowband to broadband depends on context and today is generally accepted as being in the range 64 kbit/s to 2 Mbit/s - notwithstanding that it is theoretically incorrect to refer to digital speed as a bandwidth. To add to the lack of clarity, the transition zone between narrowband and broadband is sometimes known as midband. One day, when everyone has a 500 kbit/s service and others are queuing-up to get their half-gigabit service, today's broadband will be redefined as narrowband.
A broadband service is typically delivered over ADSL over copper pairs, cable-TV systems, optical fibres or wireless access systems.
A service requiring transmission channels capable of supporting rates greater than primary rate ISDN (1.5 Mbit/s USA standard and 2 Mbit/s European standard).
Building and extending networks
The global telecommunications network is mankind's largest single structure and building a new part of it, or extending an existing part, is not to be undertaken lightly. There are many considerations to be taken into account, hopefully many of which are covered in this encyclopedia (in due course), but of the many try standards, requirements management, systems engineering, design, business planning and strategy, business case, project management, management systems (OSS), and systems integration.
Traffic which arises in bursts - particularly applied to data networks where traffic can vary from a very low level to a very high level that approaches the maximum capacity of the channel.
One of the basic forms of networks. Some examples of classic forms of a bus network are Ethernet, the PCI and ISA buses in a PC, and the IEEE488 bus (General Purpose Interface Bus - GPIB) to connect and control programmable instruments. In all cases, standard interface specifications allow the interworking of devices from different vendors.
A proposal to do something, such as building or extending a network, that requires financial authorisation and the allocation of resources. It states the business benefit of proceeding and the financial implications including current account and capital expenditures, cash flow, the payback period, labour requirements and any other relevant details. The business benefit is usually expressed as a financial benefit such as increased revenue and profit, but non-financial reasons such as safety, legal or regulatory compliance can be the driver and the case will then include the costs and effects on profitability. A business case is generally written in a non-technical way with the emphasis on financial aspects so that it can readily be understood by general managers and accountants.
A period of uninterrupted time, nominally 1 hour, during which the traffic in a telecommunications system is at its maximum level.
A term used extensively in the computer industry for a collection of bits treated as a single entity. A byte can have any number of bits. Eight is the most common, and can be assumed as the default, resulting from the early use of 8 bits in the widespread ASCII code. Unicode uses 16 bit bytes. A 4 bit byte is sometimes called a nibble and a 2 bit byte a crumb. An octet is 8 bits, and an 8 bit byte is sometimes called an octet. The abbreviation for byte is B.
The byte is typically used as a measure of storage capacity (both available and used). For example, a file will be measured in bytes or kB and the capacity of a compact disc might typically be 700 MB. It is also used as a transmission rate to show the speed of a file download (bytes/second) - but the true measure of transmission speed is the bit with which it can sometimes be confused.
Confusion has also arisen with multiples of the byte, such as a kilobyte. In the early days of computing people started using kilobyte to mean 2^10 which is actually 1024 bytes. This was a misuse of the SI prefix kilo. The problem was extended with the use of the term Megabyte. This could mean 2^20 (1,048,576 bytes), 10^6 Bytes (1,000,000) or even 1000 kilobytes (1,024,000 as used for floppy discs). To avoid this confusion a set of special prefixes has been determined by the International Electrotechnical Committee (IEC) - see units and symbols. Nevertheless confusion still exists and the proper prefixes are rarely used.
See Java
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