Computer/System Terms - R
radio frequency (RF) - (Method of classifying or measuring radio waves based on the number of cycles of a waveform per second, measured in Hertz (Hz) . The radio frequency spectrum range, at the low end, starts at 3 kHz (1000 cycles per second) and, at the high end, reaches 300 GigaHertz (Ghz) (1 billion cycles per second). Higher frequencies can carry more data, but are more subject to interference.)
radio-frequency choke (RFC) - (inductor coil designed to shield power supply lines from high-frequency signal interference)
radio frequency identification (RFID) - (Normally refers to a chip technology which provides information about the chip or what it is attached to, via radio waves. Originally, it was considered an alternative to BAR codes, for inventory tracking. The chip could be sewn into a piece of clothing or merchandise and a reader could scan the vicinity and use radio waves to locate and identify merchandise items until they were sold.)
radio frequency interference (RFI) - (The phenomenon in which a wireless signal is disrupted by a radio signal from another device or source of radio waves.)
RAID (redundant array of independent (or inexpensive) disks) Advisory Board (RAB) - (Organization formed in July 1992 to standardize, classify, and educate on the subject of RAID. The RAB no longer exists, but developed RAID specifications and a classification program.)
Rambus dynamic random access memory (RDRAM) - (memory chip manufactured by Rambus)
Rambus inline memory module (RIMM) - (plug-in memory board chips manufactured by Rambus)
Random Access Memory (RAM) - (integrated circuit for temporary storage of data and program instructions)
Random Access Memory disk drive (RAMdisk) - (virtual solid state drive)
Random Access Method of Accounting and Control (RAMAC) - (IBM computer disk storage system (1956))
Ransom Denial-of-Service (RDoS) - (Denial of service attack in which an attacker blocks or prevents access to a system, sometimes by encrypting data or blocking system operations, until a payment is made.)
Ransomware-as-a-Service (RaaS) - (An online software package sold in underground markets and/or forums using a subscription-based model, created by malware authors who develop ransomware code, package it as an online dashboard, complete with instructions, allowing for individual modification, and presented for sale or rent.)
Rapid Application Development (RAD) - (Software development model which relies on prototyping, user feedback, and the creation of workable models in stages, which are then refined as the full program is developed.)
Rate-Adaptive Digital Subscriber Line (RADSL) - (Type of high-speed digital subscriber line (DSL) which will adjust the transmission speed to match the quality and the length of the line.)
read-only memory (ROM) - (Data/routine written/burned into memory chip which can only be read, but not written to, edited, or overridden.)
read-only memory basic input/output system (ROM BIOS) - (procedure stored on memory chip)
Real-Time Blacklist Lookups (RBL) - (A service which uses the Domain Name System (DNS) protocol to do a reverse lookup to see if an IP address has been blacklisted (listed as an IP address blocked from access, usually as a source of malware or malicious conduct).)
real-time clock (RTC) - (clock chip for time/date settings)
real-time clock/nonvolatile random access memory (RTC/NVRAM) - (battery-powered clock chip for time/date settings)
Real-Time Streaming Protocol (RTSP) - (Protocol which communicates with a media server such as a video server and controls the playback of the server's media files.)
Real-Time Transport Protocol (RTP) - (Protocol providing a standardized packet format, used for delivering media-based data over networks, such as Voice over IP.)
Real-time Transport Protocol (RTP) Control Protocol (RTCP) - (protocol providing information on streaming multimedia sessions)
real use monitoring (RUM) - (tracking of actual individual user experience/activity)
reasonable expectation of privace (REP) - (legal standard)
Receiver Operating Characteristic (ROC) - (Evaluation method used in malware analysis in which true positive rates and false positive rates of detection systems are plotted against each other, resulting in an ROC "curve" or graphic picture of performance at various performance levels, intended to provide a predictive framework showing how a system is likely to perform.)
recovery point objective (RPO) - (The acceptable amount of data loss measured in time or the amount of data loss that is acceptable or the maximum amount of data that can be lost for an organization, after which the business cannot recover or would suffer significant loss. Put another way, the objective is to find alternatives which will prevent data loss or which will serve as some form of backup, so that loss does not reach the recovery point, beyond which the irreparable loss will occur.)
recovery time objective (RTO) - (A restoration projection based on the maximum amount of time an organization can be down due to a disaster or an incident.)
red, green, and blue (RGB) - (color system)
reduced instruction set computer (RISC) - (high-output chip)
Redundant Array of Independent (or Inexpensive) Disks (or Devices) (RAID) - (Computer storage technology in which data is simultaneously written to several physical disks, providing a data backup system if one of the disks fails.)
Redundant Array of Independent Tapes (RAIT) - (interconnected tape drive storage)
region code enhancement (RCE) - (video player disc copying control system)
region of interest (ROI) - (digital images)
Regional Bell Operating Companies (RBOCs) - (Name for the seven regional telephone companies formed in 1984 from the breakup of American Telephone and Telegraph (AT&T), which had held a monopoly on phone service in the U.S. until that time.)
regional Internet registries (RIRs) - (Organizations which manage, distribute, and register public Internet resources within their region.)
regional playback control (RPC) - (world geographic region disc-playing prevention system)
registration authority (RA) - (A component of, or delegated function, more often used in larger organizations, which serves the certificate authority (CA), a trusted organization (or server), which maintains and issues digital certificates within a public key infastructure (PKI) system. The registration authority serves as a kind of broker for the certificate authority, by establishing and confirming the identity of an individual, initiating the certification process, and performing certificate life-cycle management functions, before forwarding the request to the certificate authority, which then issues the certificate.)
Relative Attack Surface Quotient (RASQ) - (Relative attackability or likely opportunities for attack against software in comparison to a baseline.)
Remote Access Server (RAS) - (A Microsoft Windows Server feature that allows Microsoft Windows clients to remotely access a Microsoft Windows network. Predecessor to Microsoft Routing and Remote Access Server (RRAS).)
Remote Access Service (RAS) - (Hardware and software that allows remote users from outside a network to connect to the internal network, as if they were physically located inside the network. Remote access service handles connection, identification, authentication, and authorization processes.)
Remote Access Tools (RAT) - (Generic term for programs or software which allow a person to access and control a computer, server or system remotely. Can be used legitimately by administrators to monitor or observe user behavior, to edit and enter data, or even to instruct users. Can also be used maliciously and installed through a "Trojan Horse" embedded in a game or other program, and then to run invisibly in the background. Can be used to install other tools, such as key loggers, remote controllers, and password finders.)
Remote Access Trojan (RAT) - (Malicious program that runs on a system and allows intruders to access and use a system remotely. Characterized or distinguished from other malware by the use of a "Trojan horse" method of attack, in which they are disguised as a legitimate program, such as a game, which users are tricked into downloading from a malicious website. Once loaded on a victim's system, they allow an attacker to download or upload files, send commands, monitor user behaviors, install zombie software, activate a webcam, take screenshots, and alter or delete files.)
Remote Administration Tool (RAT) - (Software programs that give an administrator or user the ability to access and control a tech device remotely, including computer screens and keyboard functions and data entry.)
Remote Authentication Dial-In User Service (RADIUS) - (A network protocol that provides client/server authentication and authorization, and audits remote users. Used by Internet service providers (ISPs) to authenticate customers, often through a user name and password system, before they are allowed access to the Internet.)
Remote Desktop Protocol (RDP) - (A Microsoft Windows protocol that allows a user to view and control the desktop of a remote computer.)
Remote File Inclusion (RFI) - (A type of attack in which an attacker attempts to force an application to execute code from a remote site.)
remote login (rlogin) - (UNIX command allowing remote access)
Remote Procedure Call (RPC) - (A mechanism that allows a program running on one computer to execute code seamlessly on a remote system.)
remote shell (rsh) - (An application which allows commands to be executed on a computer from a remote user.)
Remote Terminal Unit (RTU) - (A special-purpose data acquisition and control device designed to support Supervisory Control and Data Acquisition (SCADA) "remote" deployments in industrial environments. RTUs are field devices that often support a variety of communications mediums.)
Report Program Generator (RPG) - (IBM programming language)
Representational State Transfer (REST) - (Cloud-based API (Application Programming Interface) governing the transfer of data in cloud-based applications. REST applies to the components, connectors, and data conduents for many web applications used on the Internet, and utilizes a stateless, cacheable, client-server protocol, almost always via HTTP.)
Request for Comment(s) (RFC) - (Semi-formal request, usually in the form of a memorandum, asking for input, criticism, or suggestions about a proposed action.)
Request for Proposals (RFP) - (product/service/bidding procurement process)
Requirements Traceability Matrix (RTM) -
Réseaux IP Européens Network Coordination Centre (RIPE NCC) - (Regional Internet Registry (RIR) for European countries, which maintains a database of company information about their Internet presence.)
research and development (R&D) -
Restrictions on Hazardous Substances (RoHS) - (European Community directive)
return on investment (ROI) - (A measure of the earning power of an investment, normally expressed as a ratio or percentage, calculated by dividing net income or income earned by the amount invested. Can be used at a company level, or at a division level to evaluate performance, or even at an asset level, to compare earnings or returns expected or earned from any given asset.)
return pointer (RP) - (programming instruction/execution)
Reverse Address Resolution Protocol (RARP) - (local server IP (Internet Protocol) address lookup)
revolutions per minute (RPM) - (speed measure)
Rich Text Format (RTF) - (Microsoft word processing file interchange format)
risk assessment (RA) - (A method of identifying vulnerabilities and threats and assessing the possible impacts to determine where to implement security controls.)
risk management (RM) - (The process of identifying and assessing risk, reducing it to an acceptable level, and ensuring that it remains at that level.)
Risk Management Framework (RMF) - (A security framework developed by the National Institute of Standards and Technology (NIST) providing guidelines, expectations, and recommended practices related to information security management in federal government agencies and systems and organizations dealing with federal agencies.)
risk management process (RMP) - (organizational threat analysis)
Rivest-Shamir-Adelman (RSA) - (Names of the three creators of the first asymmetric algorithm, in 1978, that implemented signing and encryption: Ron Rivest, Adi Shamir,and Leonard Adleman. RSA is also the name of the company they formed which provides security products and solutions for enterprise environments.)
Rock Ridge Interchange Protocol (RRIP) - (industry consortium standard for compact disc read-only memory extensions)
Role-Based Access Control (RBAC) - (A method of access security that determines the system access an individual is granted based on their role in the organization.)
root-mean-square (RMS) - (alternating current voltage measurement)
Routing Information Protocol (RIP) - (router communication/path calculation)
Routing and Remote Access Server (RRAS) - (A Microsoft Windows server feature that allows Microsoft Windows clients to remotely access a Microsoft Windows network.)
Rule-Based Access Control (RAC) or (RBAC) - (Access control model in which access is based on specific rules that govern the level of access and the amount of access granted, such as a rule imposing a time of day or days of the week access restriction, where a user would not be expected to access a database at midnight or on Saturday or Sunday.)
rule-based-role-based access control (RB-RBAC) - (access based on defined rules)
Rules of Behavior (ROB) -
run-length encoding (RLE) - (image file compression method)
run length limited (RLL) - (high-density disk encoding/storage method)
Runtime Application Self-Protection (RASP) - (A security technology that works to detect and protect against application attacks in real time.)
Russian Business Network (RBN) - (Criminal syndicate of individuals and companies that was based in St. Petersburg, Russia, but by 2007 had spread to many countries through affiliates for international cybercrime.)