Integrity aspects in presentation of ships position in onborad information systems

Electronic Chart Display and Information System became nowadays the main equipment for presentation of marine ship's position and perform of basic navigational tasks. There are new information systems under development like Marine Decision Support System. All systems require constant information about position of own ship and other objects in the vicinity. Information is gathered from onboard navigational systems. Integrity of that information is crucial for taking its full advantage and presentation in onboard information systems.