Acronyms and Abbreviations

ACRONYMS AND ABBREVIATIONS

A

ARM (Advanced RISC Machine) <processor> (ARM, Originally Acorn RISC Machine). A series of low- cost, power-efficient 32-bit RISC microprocessors for embedded control, computing, digital signal processing, games, consumer multimedia and portable applications.

ATA (AT Attachment) The IDE interface is officially known as the ATA specification. ATA-2 (Fast ATA) defined the faster transfer rates used in Enhanced IDE (EIDE). ATA-3 added interface improvements, including the ability to report potential problems (see S.M.A.R.T.). Starting with ATA-4, either the word “Ultra” or the transfer rate was added to the name in various combinations. For example, at 33 MBytes/ sec, terms such as Ultra ATA and ATA-33 have been used. In addition, Ultra ATA-33, DMA-33 and Ultra DMA-33 are also found.

C

CFA (Computer Fraud and Abuse Act of 1986) The CFA was a significant step forward in criminalizing unauthorized access to computer systems and networks. The Act applies to “federal interest computers” which include systems used by the U.S. government, as well as most financial institutions. The Act makes unauthorized penetration or other damage to such systems a felony.

CHS Cylinder, Head, Sector A disc-drive system and method for generating logical zones that each have an approximate number of spare sectors, and that are used to translate logical block addresses.

CISC (Complex Instruction Set Computer) Pronounced “sisk.” The traditional architecture of a computer which uses microcode to execute very comprehensive instructions. Instructions may be variable in length and use all addressing modes, requiring complex circuitry to decode them.

D

DMA (Direct Memory Access) Specialized circuitry or a dedicated microprocessor that transfers data from memory to memory without using the CPU. Although DMA may periodically steal cycles from the CPU, data are transferred much faster than using the CPU for every byte of transfer.

DoD (Department of Defense) The military branch of the U.S. government, which is under the direction of the Secretary of Defense, the primary defense policy adviser to the President.

DSL (Digital Subscriber Line) A technology that dramatically increases the digital capacity of ordinary telephone lines (the local loops) into the home or office. DSL speeds are tied to the distance between the customer and the telco central office (CO). DSL is geared to two types of usage. Asymmetric DSL (ADSL) is for Internet access, where fast downstream is required, but slow upstream is acceptable. Symmetric DSL (SDSL, HDSL, etc.) is designed for short haul connections that require high speed in both directions.

DSLAM (DSL Access Multiplexer) A central office (CO) device for ADSL service that combines voice traffic and DSL traffic onto a customer's DSL line. It also separates incoming phone and data signals and directs them onto the appropriate carriers network.

E

EDC/ECC (Error Detection Code/Error Correction Code) A memory system that tests for and corrects errors automatically, very often without the operating system being aware of it. When writing the data into memory, ECC circuitry generates checksums from the binary sequences in the bytes and stores them in an additional seven bits of memory for 32-bit data paths or eight bits for 64-bit paths. When data are retrieved from memory, the checksum is recomputed to determine if any data bits have been corrupted. Such systems can typically detect and automatically correct errors of one bit per word and can detect, but not correct, errors greater than one bit.

Zeus Ultra DMA Solid State Drives

33