Abstract-Many contemporary Internet protocols are extensible. Extensions may introduce new functionality, alter the format of protocol messages, affect basic functionality or even modify the protocol modus operandi. Model based testing of extensible protocols faces a number of problems, the most challenging one is that extensions altering basic functionality require changes in the protocol model. It is highly desirable to have a flexible protocol's model which would let test developers to extend the model without rewriting existing parts of the model. The article presents the method for model based conformance testing for extensible Internet protocols which satisfies this requirement. Each extension is specified in a separate unit, the method presents facility to combine those units into entire model for testing the protocol's implementations. The method uses Java language to formalize the requirements. As an example of the method application article presents test suite development for a number of SMTP extensions.

Abstract-The method for testing electronic mail protocols in the Internet to conform to the standards based on formal specifications is presented. The method is based on automated testing technology UniTESK in which functional requirements are formalized as pre-and postconditions and test sequence is generated on-the-fly from finite state machine (test state machine) traversal. The method is illustrated by the test suite development for SMTP and POP3 protocols using JavaTESK -a specification extension of Java language.