When vendors provide products, they want to ensure not only that their products are compliant with certain protocols but also that the products can work together in harmony in complex, multi-vendor environments, with other products. It is essential to ensure that all interfaces provided by their product are compatible with interfaces of other products and they can effectively communicate together. A QA engineer has to verify that different types of devices can interoperate. Using its inherent flexibility, Twister can be used to control different devices using specialized agents on each device to configure each one. Some devices can be configured using a command line interface (CLI), others a graphical user interface (GUI) or even using Simple Network Management Protocol (SNMP). Twister can handle any of these situations and is a great tool for interoperability testing.