Testing Web services by XML perturbation

The eXtensible Markup Language (XML) is widely used to transmit data across the Internet. XML schemas are used to defile the syntax of XML messages. XML-based applications can receive messages from arbitrary applications, as long as they follow the protocol defined by the schema. A receiving application must either validate XML messages, process the data in the XML message without validation, or modify the XML message to ensure that it conforms to the XML schema. A problem for developers is how well the application performs the validation, data processing, and, when necessary, transformation. This paper describes and gives examples of a method to generate tests for XML-based communication by modifying and then instantiating XML schemas. The modified schemas are based on precisely defined schema primitive perturbation operators