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Glossary of Terms (1.10.1)

Access time
A measure of hard disk and CD-ROM performance which indicates how long the device takes to find and retrieve an item of data.

The processor is connected to the memory by two electrical paths or inter-connections. The 'address bus' is used by the processor to tell the memory which addresses, or locations in memory, it wants to write to or read from. The 'data bus' is used to actually transfer the data to or from memory.

AMS - Apricot Management Suite
This is the generic term for Apricot's suite of products that allow remote management. The products to include AMS are initially just Shogun, but all future high-end servers and possibly desktops are to include remote management capabilities.

'American Standard Code for Information Interchange' A code supported by just about every computer manufacturer to represent letters, numbers, and special characters.

Asynchronous SRAM
The architecture of a static RAM (SRAMs) is simpler than that of a DRAM. No two-stage addressing is required, nor is data refreshing necessary. SRAM is thus inherently faster. SRAMs can be divided in various ways: low power or fast SRAM, (with the threshold being an access time of 35ns); asynchronous and synchronous; and even CMOS and BiCMOS. Typical asynchronous and low power SRAM usage includes mobile terminals and embedded applications. Typical densities range from 64k (100 to 150ns) through to 4Mbit (55 to 100ns access times). High speed asynchronous SRAMs also exist, densities between 256k and 4M (1M x 4) having access speeds up to 15ns. With BiCMOS, the speeds are as fast as 6ns.

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'British Approvals Board for Telecommunications' Only BABT approved modems can be used legally in the UK. Approved devices are indicated by a green 'BABT Approved' circle: modems for which there is no approval are indicated by a red triangle.

Ball Grid Array (BGA)
Increases in device integration have yielded higher function and improved performance, but have also pushed I/O counts beyond the cost effective limits of traditional SMT and pin-in-hole packages. To meet these requirements, Ball Grid Array (BGA) provide the highest I/O to body size ratio available. Other types include Ceramic Ball Grid Array (CBGA), Ceramic Column Grid Array (CCGA), Tape Ball Grid Array (TBGA) and Plastic Ball Grid Array (PBGA).

How much 'stuff' you can send through a connection. Usually measured in bits-per-second.

The 'baud rate' of a modem is how many bits it can send or receive per second. Technically, 'baud' is the number of times per second that the carrier signal shifts value - so a 2400 bit-per-second modem actually runs at 600 baud, but it moves 4 bits per baud (4 x 600 = 2400 bits-per-second).

Bulletin Board System, a computerised meeting and announcement system that allows people to carry on discussions, upload and download files, and make announcements without people being connected to the computer at the same time.

The computer uses a very simple mathematical code called binary notation where all numbers are translated into small bits, either 1 or 0, which is akin to 'on' or 'off'. Digital or 'logic' circuits are either 'on' or 'off'. They can be switched extremely fast and thus perform complex calculations very efficiently. Each successive digit represents, in normal numbers, a multiple of 2, so the number 13 for example is 1101 (8+4+0+1)in binary. You only need to fully understand Binary if you design computers, or write programs (Software) for them.

'Basic Input / Output System', like the POST, this is built into the computer. It first tests the system then instructs the processor how the whole system is set up. It holds in its own memory a record of the system components and configuration.

A single pulse in a data stream. It can be either 'on' or 'off'. See also Binary and Mbytes.

A term used to describe the computer starting up its Operating system. The operating system is held in a reserved area on either a Boot floppy disk or the Hard disk. The BIOS instructs the processor on switch on how and where to find it.

Bits-Per-Second, a measurement of how fast data is moved from one place to another. A "28.8 modem" can move 28,800 bits-per-second.

A client program (software) that is used to look at various kinds of Internet resources.

By The Way, a shorthand appended to a comment written in an online forum.

This approach promises to further extend EDO DRAM performance. A typical requirement for fast memory is to refill a cache store following a 'miss'. This involves transferring a burst of data to fill a cache line. Placing a string of addresses on the bus to generate the burst has an associated delay. Far simpler is to increment an internal memory counter once the first address has been issued. Burst EDO does just this. Most burst EDO promise a page cycle time of 15ns (a 66MHz page frequency). This is the magic figure as it corresponds to zero wait state performance for Pentium class systems. Burst EDO is being positioned as a cheaper alternative to other more radical DRAM architecture's such as the synchronous technologies.

Not big and red, but sets of inter-connections, or data highways, on the system motherboard to transfer information between the processor and the other computer parts.

Bus Bars
In the Shogun and FT4200 these are insulated metal bars, two pairs of which carry DC power from the Uninterruptible Power Supply to the power distribution panel at the top of the electronics chamber. This panel then supplies power to the motherboard and associated components. There is a third set of 3 bars, located behind the motherboard cooling fan assembly, which provides power to the hard disk drives via the hard disk power distribution panel.

Equal to 8 bits of computer data.

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Cache DRAM
A Mitsubishi inspired architecture couples a static RAM cache store within a DRAM device. The memory is designed to act as a secondary cache to high end processors having an internal level one cache. The 16kbit SRAM is connected to the 4 or 16Mbit DRAM via a 128-bit bus, with data being transferred via data transfer buffers. The device offers speeds ranging between 10 and 20ns.

Cache Memory
This is a small amount of very fast access memory in between the processor and main memory. It prevents the processor having to wait for the comparatively slower main memory to provide it with its data. It usually holds the latest, or most often read, part of the information held in the main memory. Not all computer memory can be fast as the cache, due to the considerable cost.

'Computer Based Training' Programs which allow the computer to be used for individual training, particularly for training in software applications, allowing the user to progress at their own pace.

International Consultative Committee for Telegraphy and Telephony - an organisation that produces international standards for data communications. It has recently been replaced by the ITU-T.

'Compact Disk - Read Only Memory' The advent of compact disks was a great breakthrough for computers. Large programmes and huge amounts of information could be passed around in a small sized package, with a capacity of up to 640 Mbytes. One very good example is the multimedia Encyclopaedia. The only drawback is that without an expensive drive and special disks, you cannot write information on to the disk yourself.

A software program that is used to contact and obtain data from a Server software program on another computer, often across a great distance. Each Client program is designed to work with one or more specific kinds of Server programs, and each Server requires a specific kind of Client.

Client/server network
An advanced form of server networking where the intelligence (processing program) is split, or 'distributed' between the client workstation, which handles the user interface, and the server back-end, which carries out the heavy tasks such as database searching.

Clock speed
One of the factors which affect the performance of the computer, it is measured in megahertz (usually abbreviated to MHz). The higher the clock speed, the faster the processor runs.

'Complementary Metal-Oxide Semiconductor' A special RAM chip which is used to store setup information for the computer. See also BIOS.

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Data compression
A method of reducing the amount of storage space taken up by files on disk. Files are compressed by replacing identical information (such as spaces) by special characters.

DDE - Dynamic Data Exchange
Microsoft Windows internal function for allowing co-operating applications to pass variables in real time between each other.

Device driver
A small program which controls a device or resource and provides communication between the device or resource and the computer's operating system.

Diagnostic Codes
Special codes, expressed as hexadecimal numbers, which appear on the (Shogun) front panel LCD . These codes may indicate errors or problems with the system, but can also indicate a perfectly normal sequence of events. The document, Diagnostic Codes Reference Guide, provides a definition for each code.

DIMM (Dual In-line Memory Module)
168-pin DIMMs are designed to a new industry standard using functionally unique contacts on both sides of the card. Both 3.3 V and 5.0V versions are currently available. Constructed with 4 to 64Mb DRAMs, their capacity is 8 to 128MB with future DIMMs planned to 512MB when assembled with 256Mb DRAM technology. They are 5.25 inches wide and vary in height ranging from 1 to 1.5 inches. Data busses have 64, 72 or 80 data bits. Eight buffered Presence Detect pins provide speed and density information while two additional Identity pins provide bus size and self-refresh information.

Disk Subsystem
The area of the hard disk chamber inside the Shogun which houses all of the hard disks drives. The subsystem will accommodate up to 20 drives in five modules. it also includes a cooling fan assembly, containing 2 fans, at the rear.

Desktop Management Interface.
This is a new industry standard defined by the DMTF (Desktop Management Task Force), a consortium of vendors including Compaq, DEC, HP, IBM, Dell, Microsoft, Intel & Apricot, which provides a software standard for PC manageability. The idea is for the PC to provide information which can be used for hardware and software asset management/ software distribution etc.

DRAM (Dynamic RAM)
DRAM is not the best, but it's cheap, does the job, and is available almost everywhere you look. DRAM data resides in a cell made of a capacitor and a transistor. The capacitor tends to lose data unless it's recharged every couple of milliseconds, and this recharging tends to slow down the performance of DRAM compared to speedier RAM types.

Drive Chamber
The area inside the Shogun, on the opposite side from the electronics chamber, which contains the removable media drives, System Management Controller board, hard disk cooling fans and the disk subsystem.

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Electronic Mail, messages, usually text, sent from one person to another via computer. E-mail can also be sent automatically to a large number of addresses (Mailing List).

Extended Capabilities Port operation.

'Extended Data Output' A type of RAM memory which is much faster when compared with conventional memory, to the point where its enhanced performance eliminates the need for a cache on Pentium™ 75 systems.

Extended Data Out (EDO) DRAM improves on the access speeds of FPM (Fast Page Mode) devices. The column address control pin of FPM DRAM is de-asserted prior to each issued column address, clearing the output data bus (placing it in high impedance). This imposes a setup and hold time in which the output data must be read before deactivating the control pin. EDO overcomes this by latching the output data, enabling the read to take place after the column control pin is deasserted, speeding up the overall process.
EDO shares a common manufacturing procedure with FPM, offering enhanced performance at a minimal additional cost. EDO is expected to supersede FPM DRAM. For a 50ns read access time, EDO has a typical page cycle time of 20ns, equivalent to a page frequency of up to 50MHz.

Electrically erasable EPROM, having a two-transistor cell is most expensive but is also the most flexible. It can be written to in-system and at a byte level, requiring no prior erasing. Moreover, EEPROM can be overwritten up to 1 million times. There are two EEPROM types: parallel and serial. Parallel EEPROMs have capacities up to 4Mbit (x8) and are used where large amounts of non-volatile data are required to be regularly updated. Serial EEPROMs, in contrast, have much smaller capacities and are used in myriad applications where 'personal preference' information is required. Examples include prestored frequencies for a car radio.

'Extended Industry Standard Architecture' is compatible with ISA but delivers higher performance via a 32 bit wide bus.

Electronics Chamber
The area of the interior of Shogun which contains the motherboard and associated cables and power distribution panels.

EM - Event Manager
The System Management Controller (SMC) includes a range of pre-programmed responses to AC power failure, inappropriate use of the Front Panel controls, overheating etc., each one called an Event. The Event Manager is a set of Operating System specific services which respond to these events in accordance with a script defined by the network manager or server operator.

Enhanced DRAM
Enhanced DRAM (EDRAM) is a proprietary design from Enhanced Memory Systems, a Ramtron subsidiary. The 512k x 8 device improves the performance of the DRAM by incorporating internally a static RAM cache. This provides a 15ns access speed. The SRAM block is either 2k or 8k, while the DRAM is 4Mbit. For the 2k cache, an extremely wide 256byte internal bus enables the cache to be filled from DRAM in a single 35ns access.

Enterprise network
A network covering the whole organisation - built from LANs often connected over a WAN.

Enhanced Parallel Port compatible operation.

Programmable non-volatile memory can be categorised in terms of cost versus performance. EPROM uses a single transistor cell and is relatively the cheapest (compared to EEPROM and flash). However, it is least flexible. It cannot be programmed in-system and requires UV light to be erased. EPROM usage falls into two categories: low power and more speed intensive applications. EPROMs are used when system code is unlikely to require updating. Capacities range from 16k up to 16Mbit with access speeds from 45 to 200ns.

The most common networking scheme. Uses CSMA/CD to control sharing of the cable. Runs over thin coax (cheapernet, thin Ethernet), thick coax (yellow hosepipe), or unshielded twisted pair (UTP or 10BaseT) cable. Thin coax is the cheapest way to link workstations for workgroup computing, but UTP in conjunction with hubs is increasingly being seen as the most robust and flexible solution.

'Enhanced Video Graphics Array' Screen resolutions in excess of VGA and SVGA, offering 1024 x 768 and above. See also VGA.

Expansion slots
Slots provided inside the computer to allow you to plug in expansion cards to provide new functions and capabilities. The slots may be Industry Standard Architecture (ISA), Extended Industry Standard Architecture (EISA), Micro Channel Architecture (MCA), VESA Local Bus (VL bus) or PCI.

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Frequently Asked Questions, FAQs are documents that list and answer the most common questions on a popular subject.

Fast Page Mode DRAM
DRAM consists of an array of cells, each comprising a transistor capacitor pair. To read or write data, DRAM is addressed first with a row and then a column address. Performing a read drains the cell content, however. This requires that on completion, time is spent writing the data back to the cell. In turn, the bit lines through which data is read need to be pre charged before a subsequent access can occur. The most prevalent DRAM type is fast page mode (FPM). FPM improves data access by passing the entire row (page) data to the sense amplifiers following the row address. Data in the page is then selected by strobing in the column addresses. A further performance benefit is that the write back of data and precharging is delayed until a new row address is issued. Typical page access speeds for FPM DRAM are 30ns for 50ns read access time device. This corresponds to page frequencies of up to 33MHz. FPM DRAM, at 4 and 16Mbit, is used as PC main memory store. However, FPM is increasingly failing to satisfy system requirements.

Fast SCSI-2
Although the same as SCSI-2, the data rate was doubled to 10Mbit/s. But it required more complex terminators, called active terminators. The maximum cable length was still 6m.

Fast-wide SCSI-3
A single, wide 68-pin connector enables mixed data to be transferred between wide and narrow deviceson the same bus after they have completed a negotiation process.

'Fibre Distributed Data Interface' One standard for high speed networks based on fibre-optic technology. Operates a dual ring, and can tolerate one failing, which makes it robust, so is often used to connect other networks.

The use of light (often laser) travelling down a fine glass fibre to carry information. Inherently immune to interference - allows faster communication than copper, over longer links.

File server
A computer providing a file store in server networking. A Novell server is, usually, a file server. Since the processing program is running on the workstation, there is a potential for heavy network traffic as large amounts of data are transferred to the workstation for processing.

Fire Wall
A combination of hardware and software that separates a LAN into two or more parts for security purposes.

This is a type of software that is 'embedded' in ROM inside the computer to test and start the system off when you switch the power on. See details in POST and BIOS.

Originally, flame meant to carry forth in a passionate manner in the spirit of honourable debate. "Flames" most often involved the use of flowery language and "flaming" well was an art form.

Flame War
When an online discussion degenerates into a series of personal attacks against the debaters, rather than discussion of their positions. A heated exchange.

Flash memory
Flash memory is a non-volatile memory technology and is of considerable interest to manufacturers. Flash is based on a single transistor cell architecture and resides between EPROM and EEPROM in terms of cost and flexibility. It, too, can be programmed in system and at a byte level, although it must be erased first; the erasure being performed in sectors or blocks. The main two applications being tackled by flash is solid state mass store and s an EPROM replacement for code execution. Flash comes in single and dual voltage versions, has varying erasable sector sizes, and its typically densities range from 256K to 16Mbit (a x8), with typical access speeds between 80 to 150ns.

Floppy disk
Now all new disks are 3.5 inch in size. Although in a hard plastic outer case, the disk inside is still 'floppy' or flexible, as can be seen if you slide back the metal window on one. DO NOT touch the surface. Even a small fingerprint will ruin the delicate surface permanently. Modern disks have a capacity of 1.44 Mbytes. Most software is supplied on this format, but popular now is the CD-ROM disk which has a capacity of 640 Mbytes.

FPSC - Front Panel System Controller
This is a term used in the Apricot System Management Application (SMA) that refers to both the System Management Controller (SMC) and the Front Panel board. (The front panel board includes the diagnostic LCD, buttons, power and battery LEDs and infra-red receiver).

Front Panel
The panel on the front of the Shogun that consists of the diagnostic codes LCD, the Power, Standby, Reset and Control buttons as well as the UPS and Power LEDs.

File Transfer Protocol, a very common method of moving files between two Internet sites. FTP is a special way to login to another Internet site for the purposes of retrieving and/or sending files. There are many Internet sites that have established publicly accessible repositories on material that can be obtained using FTP, by logging in using the account name "anonymous", thus these sites are called "anonymous ftp severs".

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The technical meaning is a hardware or software setup that translates between two dissimilar protocols. Another meaning of gateway is to describe any mechanism for providing access to another system.

Also known as Gbyte or GB. A byte is a collection of 8 bits in a data stream. (Giga = 1,000,000,000). Remember that Binary notation goes up in multiples of 2, so a Gigabyte is actually 1,024 Megabytes or 1,024 x 1,024 x 1024 bytes = 1,073,741,824 bytes.

A widely successful method of making menus of material available over the Internet.

'Government OSI Profile' OSI is an important standard because governments won't buy kit unless it supports OSI, as specified in a GOSIP. Unfortunately, the various GOSIPs, as published by the UK, US and Japanese governments, for example, are all slightly different.

There are many definitions of Groupware, emphasising different aspects of the concept.

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Hard disk
This is a small sealed unit fitted inside your computer that is used to store all your programs and data. It spins at high speed, has several layers and many of its components are microscopic and delicate. Its capacity can seem huge at first, but if you are not careful it seems to fill up all too fast. A typical IDE size is about 1 Gigabyte but network or office SCSI hard disks may be several times this.

Hard Disk Drive Module
The metal framework inside the disk subsystem which houses four hard disk drives. The Shogun can accommodate up to five of these modules, providing a maximum of 20 drives.

A catch-all term used to describe the whole computer system.

HDD Module Backplane
A series of small circuit boards on the back of the hard disk drive module. They are connected together by a SCSI interface cable and are semi-rigid to help overcome excessive vibration that can sometimes occur. All hard disks in the Shogun are connected to the module backplane.

Heterogeneous network
Networks, or internetworks, built up from different types of hardware running different network operating systems and using different network protocols. The norm, in the real world, and an environment with which groupware must cope.

Home page
Your starting point as a Web publisher. From here you can make links to more of your own pages, or to anyone else's.

Any computer on a network that is a repository for services available to other computers on the network.

Hot pluggable
A term which refers to the ability to remove and fit a hard disk drive easily without switching the server off. The technology involved in this feature prevents the loss of data stored on a drive which might need replacing. See also Apricot Instructor - Apricot & RAID.

HyperText Markup Language, the coding language used to create Hypertext documents for use on the World Wide Web.

HyperText Transport Protocol, the protocol for moving hypertext files across the Internet.

A central point for linking network segments in a star formation. Depending on how much you pay, allows easy addition of extra segments, reshaping of the existing segments into different logical structures, automatic isolation of faults and collection of information for automated network management.

Another feature of Web pages; allows users to move from one Web page to another at a single mouse click, irrespective of where the pages are stored.

Generally, any text that contains "links" to other documents - words or phrases in the document that can be chosen by a reader and which cause another document to be retrieved and displayed.

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'Integrated Drive Electronics' A term applied to Hard disks that are fitted into the majority of desktop computers. The drive has a board built into its casing that does a lot of the work for the processor. It controls both the way the disk is written to and read from, as well as having circuitry to communicate with the system's data BUS.

'Institute of Electrical and Electronic Engineers' An American standards-making body, responsible for many networking standards.

In My Humble Opinion, a shorthand appended to a comment written in an online form, IMHO indicates that the writer is aware that they are expressing a debatable view, probably on a subject already under discussion.

Insight BBS
A bulletin board service offered by Mitsubishi Electric's PC Division to allow the easy exchange of messages and information between our Group Technical Services Division and users of the service. Also, it allows the uploading and downloading of software and files between users of the service. Other features include up to the minute product news, technical bulletins and much more information regarding Apricot computers.

Insight Classic CD
A major element of Apricot's on-going Customer Support programme, Insight Classic CD brings together a wealth of technical and other information in a single media source, the CD-ROM. From this one definitive point of reference, the user now has immediate computer access to an increasing storehouse of information which includes System Hardware reference data, software upgrades, drivers, the complete library of Intermediate Product Bulletins, and much more. Issued on a quarterly basis, Insight Classic CD gives more information, more flexibility and more convenience, without the need for the user to maintain and update a manual, paper-based system. This product is a must for the ASC (Apricot Service Centre) and maintenance organisations.

Intel 430FX PCIset
The Intel 430FX PCIset enables the full potential of Pentium processor based systems. The 430FX includes several architectural innovations to provide high performance. In addition, the 430FX also supports new memory technologies like EDO DRAMs and pipelined burst SRAMs. With EDO DRAM support, the 430FX delivers high memory performance (X-2-2-2) and its pipelined burst SRAM support delivers high performance second-level cache (3-1-1-1). The 430FX's advanced architecture provides greater than 100 MB/s PCI data streaming, enabling a new class of applications. The new level of performance of the 430FX PCIset combine to run today's Windows* applications up to 30% faster than today's systems on the market.

Intel 450GX PCIset
The 450GX PCIset is targeted to OEMs and motherboard manufacturers designing and manufacturing Pentium Pro processor servers that deliver superior performance and upgradability through multiprocessing. The 450GX comprises of four components: a PCI Bridge, a Data Path (DP), a Data Controller (DC), and Memory Interface Component (MIC). Options for QFP (Quad Flat Pack) or BGA (BallGrid Array) packaging are available on the PCI Bridge and the DP. BGA permits OEMs and motherboard manufacturers to use less space in their design and offer greater manufacturing robustness. The 450's high reliability and scalability is obtained through Error Checking and Correction (ECC) from the Pentium Pro processor data bus out to memory and parity protection on the Pentium Pro processor address and control bus and all PCI signals. In addition, single-bit error correction is provided thereby avoiding downtime due to this error. Scalability is ensured through upgradable memory of up to 4Gbytes with 4-way interleaving for X-1-1-1 clock, data bursts.

A plug connector where a cable from a peripheral can connect to the system unit.

Interlaced display
A method of increasing the resolution of a monitor by scanning every other line of the display in one pass and then going back and filling in the missing lines. Causes the screen to flicker more than a non-interlaced display.

Probably the world's biggest network (excepting the public telephone system), a network of networks. Originally it was ARPANET, a network designed to link US military and academic resources but its scope is now worldwide.

Building up large networks by connecting smaller ones together, sometimes over large distances.

The Intranet is the use of Internet technologies within a company deployed on an internal network based on open Web technology.
Intranets exist only within organisations while the Internet is a global network open to all.
Intranets are closely related to the Internet, they share the same software and network equipment, and speak the same computer language.
Intranets run on private networks within companies and between their branch offices, fenced off from the outside Internet by "firewalls" that allow employees to look out, but keep others from looking in.
Intranets combine text, graphics and even video to distribute news, answer employee questions, update personnel records and connect far-flung workers.

IP Number
Sometimes called a "dotted quad". A unique number consisting of 4 parts separated by dots, e.g. Every machine that is on the Internet has a unique IP number. Most machines also have one or more Domain Names that are easier for people to remember.

Internet Relay Chat, basically a huge multi-user live chat facility. Anyone can create a "channel" and anything that anyone types in a given channel is seen by all others in the channel.

The IrDA physical layer specification defines communication over a distance of 1 metre, with a minimum +\- 15 degree cone from the centre of the transmitting device. The specification also defines the wavelength of the transceiver. The physical link layer is based on the common asynchronous serial port, with a few adaptations. The serial port is set to "8N1", i.e. one start bit, eight data bits, no parity, and one stop bit. The infrared transmitter is off during the idle/"space"/1 state and -- in a deviation from wired serial signalling -- on only 3/16 of the active/"mark"/0 bit period. This reduced "on" period drops the power needed to transmit and moves the emitted spectrum toward a higher frequency where it is easier to separate from other IR sources.
Note that while serial ports are capable of full-duplex communication, the IrDA interface is limited to half-duplex operation due to interference from the reflected transmit signal.

'Industry Standard Architecture' The first attempt at expanding the PC using 16 bit expansion slots, otherwise known as ISA slots. See also Bus, VESA, PCI.

Integrated Services Digital Network, basically a way to move more data over existing regular phone lines.

Internet Service Provider, an institution that provides access to the Internet in some form, usually for money.

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The device which contains typewriter keys (letters, numbers and symbols) together with function keys for shortcuts and various program functions.

Also known as Kbyte or KB. A byte is a collection of 8 bits in a data stream. (Kilo = 1,000). Remember that Binary notation goes up in multiples of 2, so a Kilobyte is actually 1,024 bytes. A kilobyte can be roughly compared to half a page of A4 text.

Knockout Panel
A small metal blanking panel which covers the centre spine opening for the hard disk module data connector. this panel must be removed when a module is installed for the first time in the Shogun's hard disk chamber.

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'Local Area Network' A data network that serves a limited geographical area such as a building or a campus.

Legacy system
The information technology which an organisation already has in place (often implies mainframe or mini-computer systems).

LIF socket
Sockets 1 and 2 are LIF (Low Insertion Force) sockets which require a tool to remove the processor.

LOC Technology
Included as standard or available as an option, this in-built, independent security system from Mitsubishi Electric's PC Division ensures that without the correct user identification and password, your system is rendered useless. The optional infra-red KeyLOC security card is used like an electronic key. In conjunction with the user identification and password features, the security system forms an unbeatable defence against even the most determined data thief.

Local bus
A method of overcoming the bottleneck caused by connecting high speed devices such as hard disks and graphics controller cards via the comparatively slow ISA bus. The local bus is a high speed 32 bit wide bus which allows high speed high bandwidth devices to bypass this bottleneck. See also VESA Local Bus, PCI.

Noun or a verb.
Noun: the account name used to gain access to a computer system. Not a secret (contrast with Password).
Verb: the act of entering into a computer system, e.g. "Login to the WELL and then go to the GBN conference."

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Maillist (or Mailing List)
A (usually automated) system that allows people to send e-mail to one address, whereupon their message is copied and sent to all of the other subscribers to the maillist. In this way, people who have many different kinds of e-mail access can participate in discussions together.

'Metropolitan Area Network' A network extending over a limited area, such as a city. Usually based on fibre-optics technology.

Masked ROM
A masked ROM (MROM) comprises an array of transistors which are programmed during manufacturing. The advantage of MROM is the small cell size compared to other non-volatile memories. MROM is used to store unchanging code and data. Densities go up to 16Mbit with x8/x16 organisations, having access times between 100 to 200ns.

or more correctly Megabytes. A byte being a collection of bits, usually 6 or 8, in a data stream. Mega = 1,000,000 (and kilo = 1000). CAREFUL now remember Binary notation goes up in multiples of 2, so a megabyte is actually 1,024 Kilobytes.

The computer uses special circuits to hold parts of the program and the data it may need for the program, in readiness for use. All information in this memory will be lost when you switch off, you must remember to save all your work before you do so.

Mission critical
Workgroup computing buzzword for the sort of data or services without which your organisation couldn't function.

MMX™ media enhancement technology is Intel's most recent processor enhancement.

This is a device for translating the digital output of a computer into a form that can be transmitted on a telephone line, two-way of course. They can be internal or external.

The device on which computer output is displayed. Sometimes referred to as a VDU (Visual Display Unit) or Screen.

The first WWW browser that was available for the Macintosh, Windows, and UNIX all with the same interface. "Mosaic" really started the popularity of the Web.

Mosys Multibank DRAM
A recent DRAM architecture from Mosys features multiple internal banks of DRAM (Synchronous-like). The DRAM has a 32-bit logical data, 16-bit physical data interface, transferring the two words on each edge of the clock (Rambus-like). Samples of an 8Mbit device having 32 internal banks are being manufactured by Siemens. The 8Mbit device is clocked at 166MHz, equating to a bandwidth performance of 664bytes per second.

The large, main board in the computer which has on it virtually all the main electronics, the processor, the memory, the ports, the IDE connections, the controls etc.

Not the furry kind, although often referred to as a rodent, but a small mechanical device sitting on the table that moves a cursor on the screen. It also has buttons that can be used to start or stop events, run programs, control an electronic paintbrush, etc.

The ability of a computer to perform more than one task simultaneously.

The capability of allowing several users to perform the same task and access the same information simultaneously.

A broad term used to describe almost anything added to a computer to make it perform a new task. Audio, TV, modem, scanner, and a great deal more.

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The etiquette on the Internet

A WWW browser and the name of a company. The Netscape™ browser was originally based on the Mosaic program developed at the National Center for Supercomputing Applications (NCSA).

A method of connecting two or more computers together to enable them to send information to each other, or to work together on a single project. If there are just a few in one building it is a Local Area Network (LAN), but if a modem to one or more other sites is used it is usually called a Wide Area Network (WAN). You can log on to one in particular with the use of a modem, called the INTERNET, a network of communications now reaching indescribable size, with huge amounts of data, based on many computers worldwide.

The name for discussion groups on Usenet.

NOS - Network Operating System
The chosen operating system running on the Shogun.

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On-line Battery Pack
The removable part of the (Shogun) Uninterruptible Power Supply which maintains power to the system when a power failure occurs. Under normal conditions the mains electricity keeps the battery pack fully charged, even when the system is switched off. There is enough power in the battery to keep a fully laden Shogun system (i.e. equipped with 20 hard disk drives) operational long enough to shut the server down. With fewer drives this operation time will be longer.

Open systems
Used in a couple of senses:
1) Most commonly refers to non-proprietary IT, such as UNIX, which isn't under the control of one single vendor.
2) An IT environment where any product from any vendor will run straight out of the box on any machine of adequate power. In this sense the proprietary MS-DOS environment is closer to an open systems environment than any UNIX environment.

Operating System
This is used to Boot the computer, telling the processor how and where to put programs, where to find them, how to use them, etc., based on the configuration it reads from the BIOS.

'Open Systems Interconnection' The overall name of the International Standards Organisation's attempt to standardise connectivity between different computers.

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Pass Through - Enables Console Redirection
A function of Apricot's System Management Application (SMA) that allows the system manager to remotely view the power-on screen of the Shogun. This also allows for the remote operation of booting from the System Management Interface Card's NVRAM allowing remote operation of the Shogun Configuration Utility (SCU) as well as upgrading various flash BIOS chips throughout the system.

A code used to gain access to a locked system. Good passwords contain letters and non-letters and are not simple combinations such as "virtue7". A good password might be: Hot$1-6

'Peripheral Component Interface' is one of the data bus connections for types of extra or expansion boards that fit inside the computer. This is the latest standard to emerge.

PCMCIA (Personal Computer Memory Card International Association) is an association of nearly 500 companies sharing a computer industry background. Their aim is to set standards for non-proprietary PC Card™ technology providing expansion options for, primarily, notebook and portable computers. The very nature of portable computer systems dictates the requirement for ever smaller and lighter expansion options including memory, storage and I/O cards. See Apricot Instructor - PCMCIA.

Portable Document Format, based on Adobe's Postscript page description language, PDF allows complex documents to be exchanged, regardless of the applications, operating systems and fonts involved.

Peer-to-peer network
A network structure where all the linked workstations are equivalent and share resources on an equal basis. The printer you are using, for example, may be physically connected to the workstation being used by another member of the team. See also client/server networking.

Picture elements or dots which make up the picture you see on the screen. Screen resolution is expressed as the number of pixels wide x number of pixels high, e.g. VGA = 640 x 480.

Plug and Play
See Apricot Instructor - Plug and Play.

Two commonly used meanings: "Point of Presence" and "Post Office Protocol". A "Point of Presence" usually means a city or location where a network can be connected to, often with dailup phone lines. So if an Internet company says they will soon have a POP in Birmingham, it means that they will soon have a local number in Birmingham and/or a place where leased lines can connect to their network. A second meaning, "Post Office Protocol" refers to the way e-mail software gets mail from a mail server.

are connections at the rear of the system, there will be ports for a printer, monitor, mouse, keyboard and serial ports for things like a modem.

'Power on self test', a routine inside the computer BIOS to test all the system components when you switch on. It will report any faults it finds on to the screen. This is held in the system ROM.

Power Distribution Board
A special circuit board which distributes power from a single source, i.e. the power supply unit, to several components. For example, the power distribution board at the top of the electronics bay (Shogun) draws power from the UPS and distributes it to the motherboard and associated components.

Point to Point Protocol, most well known as a protocol that allows a computer to use a regular telephone line and a modem to make TCP/IP connection and thus be really and truly on the Internet.

This is the bit that does most of the work in a computer. It runs software programs, it controls the system, instructing all the main system parts exactly what to do and when to do it. Most current systems use the Pentium™ processor from Intel.

'Public Switched Telephone Network' The voice-grade telephone network, the biggest electronic network the world has seen.

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'Redundant Array of Independent Disks' This technology provides a high level of data safety and integrity by enabling the storage of the same data on more than one hard disk. It then manages the data in such a way as to prevent data loss if one hard disk should fail or become corrupted. See also Apricot Instructor - Apricot & RAID.

'Random Access Memory'. All the main memory in the system is of this type. Any, or all of it, can store data which can be updated, as and when the processor requests.

Rambus DRAM
Rambus offers a novel proprietary synchronous DRAM standard. Rambus DRAMs (RDRAM) interface to an extremely high bandwidth but narrow 8-bit wide channel. The interface is clocked at 250MHz, with data transferred on both clock edges. A RDRAM is a 64-bit logical, 8-bit physical device. RDRAM uses its internal sense amplifiers as a cache to hold the entire column content of a column. RDRAMs have been adopted for some graphics systems. The technology is also being proposed as one approach to achieve a unified memory architecture. RDRAM variants include 4.5, 8, 16, and 18Mbit (2M x 9) densities.

Refresh rate
See Screen refresh rate.

Removable media drives
Refers to those drives whose storage media are removable from the drive itself. Typical examples are floppy disk, CD-ROM and tape drives.

See Screen resolution.

'Read Only Memory' can be used to describe both the area of memory used by the BIOS and a CD-ROM. As it suggests, it is readable, but the data cannot be changed.

A special-purpose computer (or software package) that handles the connection between 2 or more networks. Routers spend all their time looking at the destination addresses of the packets passing through them and deciding which route to send them on.

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A desirable feature of groupware, and other systems, where you can start with a basic system and enhance it into something more powerful, without any need to replace your environment and working practice on the way.

Scanners are devices which convert paper-based information into computer data. Photos, illustrations and logos can all be scanned in and stored on your computer's hard disk.

Screen refresh rate
A feature of the monitor, this describes the rate at which the screen image is refreshed or re-displayed. The higher the refresh rate, the less flicker will be noticeable when viewing the screen. See also Interlaced display.

Screen resolution
Screen resolution is expressed as the number of pixels wide x number of pixels high, e.g. VGA = 640 x 480.

'Small Computer System Interface' This tends to be used in larger professional systems and is used to 'Daisy chain' 2 or 3 hard disks, CD-ROMs, Scanners, Tape drives, etc., on to one single electronic interface in the system. A good SCSI control card is quite expensive, especially for just a single SCSI hard disk on it, but up to seven devices can be connected to this same interface giving an access advantage that can be enormous, along with some claims of comparative ease to fit and set up.

This was the original SCSI specification to standardise the asynchronous transfer of data between devices. A byte was transmitted by the source device which then waited for an acknowledge signal from the destination before transmitting the next byte. In practice a data rate of 2Mbit/s was achieved, which was fast compared with the maximum hard disk speed of 625Kbit/s. The cable could only be 6m long with a maximum of seven devices, plus the card, on the bus.

This used a synchronous system with a fixed-speed bus. It improved the data transfer rate to 5Mbit/s over an 8bit SCSI channel. The synchronous data transfer allowed large blocks of information to be transfered without requiringa separate acknowledge signal to be received for each byte. The number of packets without an acknowledge signal was negotiatedby the two devices at the beginning of the transfer. The maximum cable length was still 6m.

SCU - Shogun Configuration Utility
This program is used for setting the Motherboard, PCI and EISA card settings. This is supplied both on a bootable floppy disk or on the non-volatile RAM (NVRam) on the System Management Interface Card (SMIC). To access this copy of the SCU, press F2 when prompted at start-up.

Security System
A system of audible and visual alarms that warns of unauthorised access to the interior of the Shogun or tampering with the front panel controls.

Security Token
The implement which activates the alarms after the (Shogun) security system has been enabled. The removable media drive bay door key is the security token. When the door is closed and locked with the key, the system will sound the alarm when it detects a security violation.

Server networking
A network structure in which a specialised machine is used to provide resources (such as a file store) to the connected machines. Generally, unlike in peer-to-peer networking, the server or servers are the only shared resources and resources attached to individual workstations are not shared. However, some server networks have peer-to-peer features too. A special form of server networking is Client/Server.

SIMM (Single In-line Memory Module)
One type of small, standard, printed circuit boards containing memory chips that are used to build up the computer's RAM memory. See also DIMM.

SIN number
'System Identification Number' Part of the Apricot Security System, which has been certified to UKL1 under the UK Government's IT Security and Evaluation scheme and was available on some earlier products. The Security Identification Number (SIN), which is a five digit number, is shown on a label stuck to the motherboard. Before draining CMOS, it is absolutely essential that the SIN number is known, otherwise it will not be possible to enter the number on power-up and the board will be unusable. If CMOS memory is drained, the system will ask for the SIN number to be input when the system is next powered on. Beware that on a secure system the SIN number label may have been removed and kept in a safe place by the customer. If the SIN number is lost, the only course of action is to return the board to Apricot, together with proof of ownership. This service will be chargeable.

Single Connector Attachment - SCA
The Single Connector Attachment (SCA) eliminates the need for expensive paddle cards by incorporating all SCSI, power and address pins into a single 80-pin housing. All pin positions are defined with respect to each other, as well as with the drive itself, permitting a blind mating between the connector and the system. Reliability is alos increased by eliminating the cabling which always is subject to failure.

Serial Line Internet Protocol, a standard for using a regular telephone line (a "serial line") and a modem to connect a computer as a real Internet site. SLIP is gradually being replaced by PPP.

SMA - System Management Application
Apricot's Microsoft Windows based application that allows the remote management of the Shogun product.

SMC - System Management Controller
An Apricot interface board, located above the hard disk drives at the rear of the system. This board includes diagnostic processor, serial port, NVRAM and clock, that monitors all aspects of the Shogun system and environment and reports status/errors through the external serial port or via the NOS.

Switched Multimegabit Data Service, a new standard for very high-speed data transfer.

SMIC - System Management I/F Controller
This is an Apricot ISA adapter that allows the System Management Controller, via a serial link, to interrogate the motherboard and any boards plugged into it. The SMIC also contains a NVRAM that, if requested, will act as a boot disk, giving a menu on reset that allows the running of the SCU or upgrading of various BIOS chips. This is accessed either remotely or by pressing F2 at start-up.

SNMP - Simple Network Management Protocol
This is a TCP/IP associated protocol that defines the way remote management information from any product can be sent via the network and interrogated via any SNMP compliant management application. Apricot's implementation of SNMP on the Shogun is a MIB 1-2 compliant driver that is loaded in the NOS and broadcasts management variables for retrieval via third party management applications.

SO-DIMM - Small Outline Dual In-line Memory Module
A memory device that consists of a PCB board with a row of contact points on both sides of the PCB and several memory chips, usually DRAM, attached to the PCB. The PCB board provides the connection between the multiple memory chips and the computer system in a single component versus the numerous components required when using individual chips. The term generally refers to the 72-pin SO DIMM module based on a JEDEC specification

Supplied on Floppy disk or CD-ROM to load onto your computer to tell the processor inside how to control and execute the tasks you require the computer to perform. Written in a programming language and then put in a digital form on to one or more disks.

Standby Mode
When the (Shogun) system has been powered down using the Standby button under normal conditions, it is said to be in Standby Mode. in this mode, the system is switched off, but the mains electricity still keeps the UPS battery pack fully charged.

Structured cabling
Cabling an organisation so that extending the network and moving networked workstations around is comparatively simple. A little more expensive to start with than cabling to your specific current needs, but rapidly pays for itself in an organisation which depends on its network - re-cabling is extremely expensive and disruptive. Usually, structured cabling implies UTP cables feeding into hubs.

'Super Video Graphics Array' A screen resolution of 800 x 600 pixels. See also VGA.

Synchronous DRAM
Synchronous DRAM (SDRAM) is a fundamental architectural development to address the increasing gap between the data demands of micros and what DRAMs can supply. Although not intrinsically faster than standard DRAM; SDRAMs improve overall system performance. SDRAM latches some or all of the address, data and control signals within the memory device, thereby freeing the microprocessor from having to retain signal information during interaction between the two. SDRAM variants include pipelined and multi bank. Pipelined DRAMs decouple some of the internal stages, column address devode, pre amplification, and I/O drive operations, for example. De coupling the operations allows several accesses at different stages of completion to take place. Multi bank SDRAMs use multiple internal memory banks, enabling refreshing and precharging to occur during a separate bank access. SDRAMs offer cycle times of 10ns (100MHz). This is beyond the performance of Burst EDO. SDRAMs are being used in graphics systems. It is also being targeted as the main memory for high end computer system, and for set-top box applications. SDRAMs are relatively expensive due to the silicon overhead of the additional control circuitry. Typical configurations for SDRAM are 16Mbit with 4M x 4, 2M x 8, and 1M x 16 data bus widths.

Synchronous SRAM
Synchronous SRAM (SSRAM) is mostly used as level two cache for 486, Pentium and PowerPC. As with SDRAMs, being self-timed, the devices increase overall system performance. For level two cache, SSRAM operate in a burst mode, with data accesses overlapped internally for burst fills. Here the most popular parts are the 1Mbit (32k x 32 and 32k x 36) with 2M and 4M versions to come. Burst mode SRAM are further divided into pipelined and (non-pipelined) 'flow through' versions. Flow through does not have an output register while the pipeline variant does. Highest performance SSRAMs are pipelined. SRAM bandwidth performance is from 66MHz upwards.

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A leased-line connection capable of carrying data at 1,544,000 bits-per-second. At maximum theoretical capacity, a T-1 line could move a megabyte in less than 10 seconds.

A leased-line connection capable of carrying data at 45,000,000 bits-per-second.

Tape drive
A device, which may be internal or external, into which magnetic tapes can be placed to copy information to or from your computer. Normally used to backup and restore information from or to your hard disk.

Transmission Control Protocol/Internet Protocol, this is the suite of protocols that defines the Internet. Originally designed for the UNIX operating system, TCP/IP software is now available for every major kind of computer operating system.

Working outside the office (usually at home) and communicating with the office by phone. Lends itself to workgroup computing solutions.

The command and program used to login from Internet site to another.

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Ultra SCSI
The SCSI-3 specification also contained proposals to double the data transfer rate on the bus, again to 20Mbit/s on a narrow channel and 40Mbit/s on a wide channel. This improvement was given the name Fast20 by Ansi and is often called ultra SCSI. Ultra SCSI also specifies that the bus width must be constant. The maximum cable lengths are reduced to 3m with 4 devices and 1.5m with eight devices.

Universal Serial Bus (USB)
The Universal Serial Bus is specified to be an industry standard extension to the PC architecture with a focus on Computer Telephony Integration (CTI), consumer, and productivity applications. The following criteria were applied in defining the architecture for the Universal Serial Bus:

Ease of use for PC peripheral expansion
Low-cost solution that supports transfer rates up to 12 Mbs
Full support for the real-time data for voice, audio, and compressed video
Protocol flexibility for mixed-mode isochronous data transfers and asynchronous messaging
Integration in commodity device technology
Comprehend various PC configurations and form factors
Provide a standard interface capable of quick diffusion into product
Enable new classes of devices that augment the PC's capability

UPS - Uninterruptible Power Supply
A device which is designed to maintain DC electricity supply to the system for a limited period in the event of a mains power failure. This period gives you enough time to log users of the network and shut the system down without the danger of loss or corruption of data and programs.

UPS Circuit Breaker Switch
A switch on the backplane of the Shogun which isolates the power supply from the mains electricity. This switch should always be set to Off when any service procedure or other exceptional intrusion into the machine is carried out.

Uniform Resource Locator, the standard way to give the address of any resource on the Internet that is part of the World Wide Web (WWW).

A world-wide system of discussion groups, with comments passed among hundreds of thousands of machines. Not all Usenet machines are on the Internet, maybe half. Usenet is completely decentralised, with over 10,000 discussion areas, called newsgroups.

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'Value Added Network' A wide area network (WAN) supplied by a third party and offering services to users above and beyond simple connectivity.

The Video Electronics Standards Association was set up to standardise video and monitor functionality, such as standard resolutions and colour depth combinations, standard programming interfaces, etc. See also VESA Local Bus.

VESA Local Bus
One of the two local bus architectures for attaching high speed devices to the system. The bus is 32 bits wide and runs at 33MHz. Also known as VL bus. See also Local Bus.

'Video Graphics Array' is a graphics standard of video output for modern high resolution monitors, but most manufacturers, like Apricot, have extended this to Super VGA or to Enhanced VGA, giving fine resolution up to 1024 x 768 on capable monitors. (This makes text very small on a screen unless your monitor is 15 inch or larger). 800 x 600 is a common and popular setting for most users.

Video RAM
Random Access Memory which is provided specifically for the purpose of manipulating the video display. The number of colours and maximum screen resolution is governed by the amount of Video RAM in the system.

A piece of code which can attach to a program and make further copies of itself. May or may not cause malicious (or accidental) damage but is a serious nuisance, particularly in a connected environment where you depend on IT. Various anti-virus programs are available, but should always be supplemented with effective backup procedures.

This type of RAM sits on the better class of graphics display adapters. Unlike its general-purpose cousin dynamic RAM (DRAM), VRAM has dual ports--a design that can read and write data at the same time and is thus faster than DRAM.

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'Wide Area Network' A data network that serves a wide geographical area, which could be global, by the use of modems to link local networks together.

This doubled the width of the SCSI bus to 16bit so two bytes can be transfered at a time, and the data rate became 20Mbit/s. It required two cabled and connectors for each drive and was rapidly replaced by fast-wide SCSI-3.

Originally use to distinguish powerful UNIX terminals from PCs, but now used to describe any networked computer when it isn't particularly relevant whether it has the PC architecture or not.

World Wide Web (WWW)
Part of the Internet, it is a set of inter-connected non-commercial communications networks.

WRAM (Windows RAM)
WRAM, a revolutionary dual-ported memory, is up to 50% faster than the fastest types of VRAM, and can be clocked at 50 MHz resulting in a frame buffer bandwidth of 960 MB/sec. Its two ports allow both the input of graphic drawing data and output of screen refresh data to be processed simultaneously, doubling its data bandwidth.

'What You See Is What I See' - the guarantee that all users of a shared object have the same view of it, which is pretty useful to collaborative working.

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ZIF socket
Sockets 3, 4 and 5 are ZIF (Zero Insertion Force) sockets which allow the insertion and removal of the processor via a lever which locks or unlocks the processor in the socket.

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Computing for a Connected World