Analog Subscriber Call Generator

The paper describes the development of the analog subscriber Call Generator (CG) for the SI2000 V5 switch node. It provides developers with the test environment without the use of external testing units. The proposed architecture assures effective tests of program layers above the driver of analog subscriber circuits. This was accomplished with minimal changes of the existing program code and application of the existing communication procedures. Compared to external testing units, the software Call Generator possesses some limitations. Because of the software nature of its operation, electrical interfaces on analog subscriber line circuits are not tested for proper operation. Also, usual audio checks of the connection are not performed. The call generator can be extended with this functionality, but this would demand greater changes of the existing program code and an additional use of digital signal processing resources. This would impose unnatural performance of the switch node under test. Testing without using external testing units represents the main achievement for the developer. For the CG operation, only an IP connection between the developer’s workstation and the tested switch node is required. Developers can control and monitor the execution of tests from their development workstation with any WWW (World Wide Web) browser.