Independent – loosely coupled with one another § Negotiable – Stories are what and why , not how ( 99% ). § Valuable – for the customer! § Estimateable – Effort/Cost of design, build, and test. § Small (sized appropriately) § Testable – pass or fail
what (reactions, behaviours, or services) the system should not do. b) services the system should provide, c) how the system should react to particular inputs, and d) how the system should behave in particular situations.
to user to search from various invoices. b) User should be able to mail a report to management. c) Users can be divided into groups and groups can be given separate rights. d) Move the ghost in the Pac-man video game
Constraints on the services or functions offered by the system, such as Standards to apply, development platform, timing constraints, constraints on the development process, etc. b) Quality attributes, such as performance specifications, robustness, usability, etc.
• Processed transactions/second • User/event response time • Screen refresh time Size • Mbytes • Number of ROM chips Ease of use • Training time • Number of help frames Reliability • Mean time to failure • Probability of unavailability • Rate of failure occurrence • Availability Robustness • Time to restart after failure • Percentage of events causing failure • Probability of data corruption on failure Portability • Percentage of target dependent statements • Number of target systems