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Strategy Bridge

Systems Engineering Glossary

Term Definition

Streamlining, adapting, or otherwise changing an established approach or process to address a specific application.

Technical Performance Measures

Specific non-cost/ non-schedule metrics chosen to provide early insight into the expected performance against requirements as a predictor of system Measures of Performance (MOP).

Technology Readiness Level (TRL)

A graded scale of technology maturity levels useful in assessing technical risk and implementation viability.


A verification (or validation) technique involving instrumentation under controlled conditions to assess whether an entity meets specified requirements (or operational capabilities).

Test Case

A test case is a set of controlled conditions or variables that are executed to determine whether a system under test satisfies requirements.

Test Lead

The person responsible for planning the test life cycle activities and deliverables, providing technical focus to the test team, and developing and managing to the schedule.

Test Plan

A document describing the detailed approach for performing testing at each test level.  It defines the detailed set and sequence of specific test cases to be executed, the organizational roles and responsibilities, and associated test schedules.

Test Procedure

The detailed information and steps required to perform a test.  The test environment, to include hardware, software, data, scripts, and their version and configuration is documented, along with the evaluation criteria necessary to prove a requirement was satisfied.

Test Readiness Review (TRR)

A review to evaluate and confirm that an entity is ready for a test and the test procedures are under configuration control.


A process to show the relationships (upwards and downwards in a requirements hierarchy) between sources, decomposition, and implementation of requirements.

Trace Deficiency

A trace deficiency exists when a requirement statement cannot be fully traced back to its authorizing source (orphan), or has no path for realization (childless parent).


A visible relationship among two or more logical entities, for example, requirements.

Trade Study

A process to evaluate system alternatives against specific evaluation criteria in order to select the best solution.


The decision-making actions to select the best alternative among multiple options.


The process of moving from one life cycle stage or level of the system hierarchy to another.  The term is often used to refer to the shift from the development environment to the operational environment.