부산대학교 도서관

Communication and positioning protocols for underwater acoustic sensor networks are widely covered in the scientific papers during the last decade and partly implemented in a few proprietary and open-source networking frameworks. The different protocols to be combined in a stack running on an acoustic modems' hardware and thus to solve various tasks of practical interest. This paper presents a novel framework for underwater acoustic sensor networks and positioning systems, designed as lightweight yet efficient and easily extensible tool. Evologics intelligent Networking Software Framework (EviNS Framework) follows a paradigm of event driven programming, each module is explicitly defined in form of a pushdown automata and is driven purely by discrete events generated internally by event handles, by timers or externally by interface processors. The task of the interface processor is to provide the mechanism to receive and parse this data, and pass it to the module. The task of the module is to handle this event, update the state and pass back to the interface processor tuples, to be converted to the appropriate format and delivered via the appropriate interface. The framework has relatively moderate system requirements and can be run directly on the EvoLogics acoustic modems' hardware or can be used with the DMACE a real-time emulator of EvoLogics underwater acoustic modems. The emulator provides a fully-featured emulation of the data-link layer and includes a phenomenological simulator of the physical layer that accounts for signal propagation delays, multipath propagation, data packet collisions, packet synchronization errors and bit errors with a user-defined bit error rate. EviNS along with the DMACE builds comprehensive set of tools for development, testing, deployment and operation of a great variety of communication and positioning solutions for underwater acoustic sensor networks (UASN). Open source modules supporting other acoustic modems can be added by the modem suppliers or keen developers. The paper explains the reasons of the programming language choice and its implications on the framework features. The frameworks architecture is presented with several implementation examples of known MAC protocols for UASN.