TD is our own test design supporting system. It eliminates unevenness of testing qualities among testers by making implicit experience and know-how of skilled testers apparent and by integrating them into the system. TD loads about 800 of standard check points for systems based on our large amount of test results.
CAT accumulates automatically standardized knowledge for every version and can apply test cases among projects.
With CAT, since you can control versions of test design data, it is easy to see their changes such as additions and deletions of the data among their versions.