Abstract
Model-based Testing (MBT) is an approach for generating test cases automatically from abstract models of the system under test (SUT). The resulting test cases are also abstract and they have to be concretized before being applied to the SUT. This task is typically delegated to the test adaptation layer. The test adaptation is usually created manually which is tedious and error prone. In this paper, we present an approach in which we take advantage of an existing test execution framework for implementing the test adaptation between an on-line MBT tool and the SUT. The approach allows the reuse of message libraries and automatic concretization/abstraction of tests in on-line testing. In addition, we also discuss ways to automate the building of the test adaptation from other artifacts of the testing process. We exemplify our approach with excerpts from a telecom case study.