Letter: A

Access controls define who can view or use systems, files or workflows based on set permissions. They restrict unauthorized access and help enforce security policies and compliance.

An active-active cluster uses multiple nodes that run at the same time to process workloads. It improves uptime by balancing traffic and removing single points of failure.

Ad-hoc file transfer is a one-time, user-initiated file exchange without predefined workflows. It allows quick sharing but still requires security controls like encryption and access limits.

AES is a widely used symmetric encryption standard that protects sensitive data in transit and at rest. It replaced older methods like 3DES due to stronger security and better performance.

Air-gapped networks are systems physically isolated from external connections. This separation prevents remote access and helps protect highly sensitive data.

ANSI X.9 is a set of financial industry standards that define secure electronic transactions. It covers areas like encryption, key management and financial messaging.

Antivirus scanning checks files for malware before or after transfer using known threat patterns. It helps protect systems and ensures files are safe to use or share.

AS3 is a file-based protocol that sends EDI data over FTP or FTPS using a store-and-forward model. It allows partners to retrieve messages asynchronously instead of relying on real-time delivery.

AS1 is an EDI protocol that sends encrypted and signed messages over email using SMTP and S/MIME. It supports secure business data exchange with non-repudiation.

AS2 is an HTTP-based protocol for securely transmitting EDI data over the internet. It uses encryption, digital signatures and receipts to confirm delivery and protect message integrity.

AS4 is a web services-based standard for secure B2B data exchange using SOAP and ebMS 3.0. It supports reliable messaging, scalability and interoperability across enterprise systems.

An API is a set of rules that allows software systems to communicate and exchange data. It enables automation, integration and workflow execution across platforms.

Audit logging captures system events like file transfers, logins and configuration changes. It provides visibility for monitoring activity, investigating issues and meeting compliance requirements.

An audit trail is a time-ordered record of actions taken within a system or workflow. It shows who did what and when to support accountability and traceability.

Auto scaling automatically adjusts system resources based on workload demand. It helps maintain performance during spikes while reducing unused capacity during low activity.