The FREE Cybersecurity Glossary by Thor Pedersen!

Arbitrary Code Execution: A security vulnerability that allows an attacker to run unauthorized code on a system or network. It can lead to a full system compromise and is a critical threat to cybersecurity. Examples include exploitation through software vulnerabilities such as buffer overflows or injection flaws.

Arbitration: In the context of data transmission, arbitration is the process used to determine which device has control over the communication line at any given time. In a network where multiple devices may need to transmit data simultaneously, an arbitration mechanism ensures that only one device transmits at a time to avoid data collisions. This process is particularly crucial in bus networks or other shared-medium networks where the possibility of data collision is high.

Architecture: The overall design and structure of a system, including the components, relationships, and interfaces between them. In the context of information security, architecture refers to the design of an organization's security infrastructure and the ways in which it protects against various threats and vulnerabilities. Examples of security architecture include network architecture, application architecture, and data architecture.

Archive Bit: A flag or attribute associated with a file or directory that indicates whether it has been modified since the last time it was backed up. The archive bit is commonly used in backup software to identify which files need to be copied or transferred to a storage device.

Area Border Router (ABR): A router that connects different OSPF (Open Shortest Path First) areas within a network. It is used to connect different OSPF areas and allow for communication between them. Examples include routers in a large enterprise network or a service provider network.

Arithmetic Logic Unit (ALU): A fundamental building block of a central processing unit (CPU) in a computer system. It performs arithmetic and logical operations on the data stored in the system's registers or memory. Its functions include addition, subtraction, multiplication, and division, along with bitwise operations and comparisons.