Security, Accuracy and Privacy in Computer Systems - James Martin
Reasonableness Test: For example. a charge of $500 might be reasonable on a corporations electricity bill but not on an individuals bill. Consistency Test: In an airline booking to Chicago the trans action may be checked to ensure that the flight number in it does in fact go to Chicago. Special Tests: Dates may be checked to ensure that the month is between I and l2. that the day is between l and 28, 29, 30, or 31. depending upon the month. Self Checking Numbers: The extra digit is derived arithmetically from the other digits.