Abstract: A network bus for interconnecting a plurality of medical devices is described in which the devices are provided with modules adapted to communicate along the bus. Some of the devices are capable of assuming control over the bus with network master modules. A self-configuring capability is provided with which several network master capable medical devices automatically determine which network master is to take over control over the network bus and each individually is capable of controlling and operating the network. Each network master capable device has an extended network management module with which automatic master selection is achieved. This is done by monitoring or observing network communications for particular objects. Once such an object has been detected, a network master capable device is automatically selected to take over control on the basis of its priority.