Twouser

Twouser is a term encountered in discussions of multi-user system design and access control. In its broadest sense, twouser refers to a system, mode, or policy that requires involvement of two distinct user identities to authorize or participate in a given operation. The concept is often described as dual-authentication or two-person control, and is used to improve accountability and security in sensitive workflows.

Usage and scope: The term is not a standardized formal concept; it tends to appear in design documents, security guidelines, or product discussions to denote a two-person requirement rather than a single-user action. It can apply to high-risk financial operations, governance processes, or collaborative tasks where mutual verification is desirable.

Implementation: Typical approaches include dual authentication (two separate logins or tokens), role separation where each user has distinct privileges, and explicit workflow steps that require approvals from both parties. Auditing and tamper-evidence are common, ensuring an action can be traced to both users. Privacy and latency are considerations, as multiple identities increase friction.

Examples: A database transaction that requires two approvals before commit; a corporate expense system requiring two signatories; collaborative document workflows where two editors must confirm changes.

Limitations: It can impede efficiency and may not be suitable for all tasks; proper design is required to avoid deadlocks or privacy issues; compatibility with existing authentication systems is a consideration.