Flashcards in Acronyms Deck (30)
Alternating Current-the flow of current reverses its direction periodically. Alternating current in a circuit is represented by the sine wave
Access Control List-permissions attached to an object that specify which users are granted access to that object and the operations it is allowed to perform.
Each entry in an access control list specifies the subject and an associated operation that is permitted.
Advanced Encryption Standard-symmetric-key block cipher algorithm and U.S. government standard for secure and classified data encryption and decryption.
The AES has three fixed 128-bit block ciphers with cryptographic key sizes of 128, 192 and 256 bits. Key size is unlimited, whereas the block size maximum is 256 bits.
All In One-computer that has every component within the same case as the monitor, except for peripheral components like the keyboard and mouse.
Automatic Private Internet Protocol Addressing-Microsoft’s terminology for address autoconfiguration in the Windows 98, ME, 2000 and XP OSs. APIPA allows a local area network (LAN) computer to give itself a unique IP address when Dynamic Host Configuration Protocol (DHCP) is unavailable.
APIPA is sometimes known as auto-IP.
Advanced RISC Machines-processor architecture based on a 32-bit reduced instruction set (RISC) computer. Licensed worldwide, the ARM architecture is the most commonly implemented 32-bit instruction set architecture. ARM architecture is implemented on Windows, Unix, and Unix-like operating systems, including Apple iOS, Android, BSD, Inferno, Solaris, WebOS, Plan 9 and GNU/Linux.
Address Resolution Protocol-low-level network protocol for translating network layer addresses into link layer addresses.
ARP lies between layers 2 and 3 of the OSI model, although ARP was not included in the OSI framework and allows computers to introduce each other across a network prior to communication.
Because protocols are basic network communication units, address resolution is dependent on protocols such as ARP, which is the only reliable method of handling required tasks.
American Standard Code for Information Interchange-is a method of encoding characters that is based on the order of alphabetic characters in the English language.
ASCII integer representations have printable and nonprintable subsets. Printable characters are normal characters, and nonprintable characters are characters used to represent keyboard keys, e.g., backspace, delete, and return.
Blue-Ray Disc Read Only Memory-Read-only is a designation for any object or construct which can no longer be altered after creation, it can only be read.
This can refer to both hardware and software constructs such as read-only memory chips like BIOS and CMOS and CD/DVD/Blu-ray-ROMs for hardware, and read-only files for software constructs. In either case the contents of the object when marked as read-only can no longer be changed, only accessed or read.
Basic Input/ Output System-is a preinstalled program used during startup on Windows-based computers. The CPU initially accesses the BIOS, after which the operating system is loaded.
The BIOS is built-in software that contains generic code required to control the keyboard, display screens, disk drives and other functions. The primary purpose of the BIOS is to set up hardware and further load and start an operating system. BIOS is placed in a nonvolatile ROM chip inside the computer, ensuring the availability of BIOS at all times and preventing accidental disk failure. The BIOS checks every hardware connection and locates the devices, after which the operating system is loaded into computer memory.
BIOS software is designed to work with the various devices that make up a complimentary system chipset. The BIOS library has certain functions used to operate and control system peripherals, which can be initiated by an external software.
Users using the BIOS user interface can perform functions such as:
Setting the system clock
Enabling and disabling certain system components
Selecting boot drives
Set password prompts for secured access to BIOS user interface function
Modern PCs have BIOS stored in rewritable memory, permitting contents to be rewritten or replaced. Such content rewriting is called flashing and is executed through a special program provided by system manufacturers.
Computer-Aided Design-is an application technology that uses computer software and machinery to facilitate and automate manufacturing processes. CAM is the successor of computer-aided engineering (CAE) and is often used in tandem with computer-aided design (CAD).
In addition to materials requirements, modern CAM systems include real-time controls and robotics.
CAM reduces waste and energy for enhanced manufacturing and production efficiency via increased production speeds, raw material consistency and more precise tooling accuracy.
CAM uses computer-driven manufacturing processes for additional automation of management, material tracking, planning and transportation. CAM also implements advanced productivity tools like simulation and optimization to leverage professional skills.
Compact Disc-molded plastic disc containing digital data that is scanned by a laser beam for the reproduction of recorded sound and other information.
Compact Disc Read Only Memory-is a storage device that can be read but not written to.
CD-ROM was a common convention for delivery of audio and other data through the years before small solid-state flash drives and other devices began to take over.
Compact Disc Rewritable-refers to an optical CD that may be written and rewritten multiple times. CD-RW allows for data erasing during each rewritable session. However, data cannot be changed during CD-RW sessions. Some CD-RW discs have a multisession feature, in which additional data may be written at a later time if extra space is available.
Central Processing Unit-is the unit which performs most of the processing inside a computer. It processes all instructions received by software running on the PC and by other hardware components, and acts as a powerful calculator.
The CPU is placed into a specific square-shaped socket found on all motherboards by inserting its metallic connectors or pins found on the underside. Each socket is built with a specific pin layout to support only a specific type of processor.
Since modern CPUs produce a lot of heat and are prone to overheating, they must be kept cool with appropriate fans or ventilation systems, and covered with heat sinks and thermal paste.
To control instructions and data flow to and from other parts of the computer, the CPU relies heavily on a chipset, which is a group of microchips located on the motherboard.
Create, Read, Update, Delete-refers to the four major functions implemented in database applications.
The CRUD functions are the user interfaces to databases, as they permit users to create, view, modify and alter data. CRUD works on entities in databases and manipulates these entities. Any simple database table enforces CRUD constraints.
For instance, a simple student database table adds (creates) new student details, accesses (reads) existing student details, modifies (updates) existing student data such as subjects, and deletes student details when students leave the school.
The commands corresponding to these operations in SQL are INSERT, SELECT, UPDATE and DELETE. INSERT adds new records, SELECT retrieves or selects existing records based on selection conditions, UPDATE modifies existing records and DELETE removes tables or records.
Cascading Style Sheets-standard (or language) that describes the formatting of markup language pages. CSS defines formatting for the following document types:
HyperText Markup Language (HTML)
Extensible HyperText Markup Language (XHTML)
Extensible Markup Language (XML)
Scalable Vector Graphic (SVG)
XML User Interface Language (XUL)
CSS enables developers to separate content and visual elements for greater page control and flexibility. A CSS file is normally attached to an HTML file by means of a link in the HTML file.
Direct Current-flows in the same direction continuously. An example of direct current would be the current provided by a battery. In order to calculate the current flow through a conductor, PC use direct current
data definition language (DDL) is a computer language used to create and modify the structure of database objects in a database. These database objects include views, schemas, tables, indexes, etc.
This term is also known as data description language in some contexts, as it describes the fields and records in a database table.
Commonly used DDL in SQL querying are:
CREATE: This command builds a new table and has a predefined syntax. The CREATE statement syntax is CREATE TABLE [table name] ([column definitions]) [table parameters]. CREATE TABLE Employee (Employee Id INTEGER PRIMARY KEY, First name CHAR (50) NULL, Last name CHAR (75) NOT NULL).
ALTER: An alter command modifies an existing database table. This command can add up additional column, drop existing columns and even change the data type of columns involved in a database table. An alter command syntax is ALTER object type object name parameters. ALTER TABLE Employee ADD DOB Date.
DROP: A drop command deletes a table, index or view. Drop statement syntax is DROP object type object name. DROP TABLE Employee.
distributed denial-of-service (DDoS) is a type of computer attack that uses a number of hosts to overwhelm a server, causing a website to experience a complete system crash. This type of denial-of-service attack is perpetrated by hackers to target large-scale, far-reaching and popular websites in an effort to disable them, either temporarily or permanently. This is often done by bombarding the targeted server with information requests, which disables the main system and prevents it from operating. This leaves the site's users unable to access the targeted website.
DDoS differs from a denial-of-service (DoS) attack in that it uses several hosts to bombard a server, whereas in a DoS attack, a single host is used.
Double Data-Rate-advanced version of synchronous dynamic random access memory (SDRAM). SDRAM waits for clock signals before responding to control inputs. DDR uses both the falling and rising edges of the clock signal. The difference between SDRAM and DDR is not the speed, but rather how many times data is transmitted with each cycle. DDR transfers data twice per clock cycle, whereas SDRAM sends signals once per clock cycle. The same frequencies are used for both. However, DDR uses both edges of the clock, whereas SDRAM uses only one. DDR is outdated but is still in use, such as for the output of analog-to-digital converters. Updated DDR versions are DDR2 and DDR3.
DDR is also known as dual pumped rate, double pumped rate or double transition rate.
Dynamic Host Configuration Protocol-Dynamic Host Configuration Protocol (DHCP) is a network management protocol used to dynamically assign an IP address to any new node entering the network. DHCP permits a node to be configured automatically, thereby avoiding the necessity of involvement by a network administrator.
DHCP does the following:
Manages the provision of all the nodes added or dropped from the network
Maintains the unique IP address of the host using a DHCP server
Sends a request to the DHCP server whenever a client/node, which is configured to work with DHCP, connects to a network. The server acknowledges by providing an IP address to the client/node.
Dynamic Host Configuration Protocol is also known as RFC 2131.
Dual Inline Memory Module-ine Memory Module (DIMM) mean?
A dual inline memory module (DIMM) is a small-scale circuit board that holds memory chips on the motherboard. DIMM incorporates a series of memory called dynamic random access memory (DRAM), which provides primary storage, the main memory that continually reads and executes stored instructions or data directly to the CPU.
DIMM is an attempt to improve on the earlier single inline memory module (SIMM), which used matched pairs. DIMM uses only one circuit board, thus increasing memory speed and storage. DIMM also has a much smaller circuit board and easier insertion compared to SIMM.
Dynamic Link Layer- a shared program module with ordered code, methods, functions, enums and structures that may be dynamically called by an executing program during run time. A DLL usually has a file extension ending in .dll. Other file extensions are .drv and .ocx.
DLLs were developed by Microsoft and work only with the Windows operating system (OS).
Data Leak Prevention-refers to the identification and monitoring of sensitive data to ensure that it's only accessed by authorized users and that there are safeguards against data leaks. Major insider threats as well as more stringent state privacy laws triggered the adoption of DLP in 2006.
Data Manipulation Language- is a family of computer languages including commands permitting users to manipulate data in a database. This manipulation involves inserting data into database tables, retrieving existing data, deleting data from existing tables and modifying existing data. DML is mostly incorporated in SQL databases.
DML resembles simple English language and enhances efficient user interaction with the system. The functional capability of DML is organized in manipulation commands like SELECT, UPDATE, INSERT INTO and DELETE FROM, as described below:
SELECT: This command is used to retrieve rows from a table. The syntax is SELECT [column name(s)] from [table name] where [conditions]. SELECT is the most widely used DML command in SQL.
UPDATE: This command modifies data of one or more records. An update command syntax is UPDATE [table name] SET [column name = value] where [condition].
INSERT: This command adds one or more records to a database table. The insert command syntax is INSERT INTO [table name] [column(s)] VALUES [value(s)].
DELETE: This command removes one or more records from a table according to specified conditions. Delete command syntax is DELETE FROM [table name] where [condition].
Domain Name Service or Server-type of name server that manages, maintains and processes Internet domain names and their associated records. In other words, a DNS server is the primary component that implements the DNS (Domain Name System) protocol and provisions domain name resolution services to Web hosts and clients on an IP-based network.
Denial of Service-type of attack where the attackers (hackers) attempt to prevent legitimate users from accessing the service. In a DoS attack, the attacker usually sends excessive messages asking the network or server to authenticate requests that have invalid return addresses. The network or server will not be able to find the return address of the attacker when sending the authentication approval, causing the server to wait before closing the connection. When the server closes the connection, the attacker sends more authentication messages with invalid return addresses. Hence, the process of authentication and server wait will begin again, keeping the network or server busy.
A DoS attack can be done in a several ways. The basic types of DoS attack include:
Flooding the network to prevent legitimate network traffic
Disrupting the connections between two machines, thus preventing access to a service
Preventing a particular individual from accessing a service.
Disrupting a service to a specific system or individual
Disrupting the state of information, such resetting of TCP sessions
Another variant of the DoS is the smurf attack. This involves emails with automatic responses. If someone emails hundreds of email messages with a fake return email address to hundreds of people in an organization with an autoresponder on in their email, the initial sent messages can become thousands sent to the fake email address. If that fake email address actually belongs to someone, this can overwhelm that person's account.
DoS attacks can cause the following problems:
Interruption of network traffic
Digital Subscriber Line-technology that transports high-bandwidth data over a simple telephone line that is directly connected to a modem. This allows for file-sharing, and the transmission of pictures and graphics, multimedia data, audio and video conferencing and much more. DSL uses the analog medium, which is reliable and prevents interruptions and heavy packet loss. DSL is fast and provides low user subscription rates.