have been approved by the fishing vessel's state of registry and the functionality requirements. Normally an authority will specify specific approved equipment to ensure end to end system integrity and service level meeting the specific requirements applicable to the vessel type. For example, some systems require a user interface on the vessel, whilst others will have a simple black box transceiver with no user interface. VMS software and devices for the fishing vessel include: Absolute Software AMS Argonet-vms CLS AST Ltd Globavista/Bluefinger/Thales BlueTraker Boatracs CLS America - Thorium VMS Faria Free Port - Eye from a sky Fulcrum Maritime Systems - Vessel Tracking, Fleet Tracking, Fisheries Monitoring Honeywell Maritime Systems - Inshore Vessel Monitoring System Monicap Skymate SRT Marine System Solutions Thrane & Thrane VMS MetOcean Telematics iTrac VMS GMV Communications VMS units principally rely on global navigation satellite systems (GNSS) such as GPS for position and time information. LORAN may be a backup or complementary technology. These transceivers transmit data to monitoring systems generally using a variety of communication technologies including terrestrial & satellite AIS and conventional satellite systems from Inmarsat, Iridium, Argos, Orbcomm or Qualcomm. Increasingly nations are implementing a mixture of technologies with the largest vessels over 60 tons being required to use the expensive traditional satellites and smaller vessels to use AIS. Operated by Inmarsat plc, founded by governments but now commercial, Inmarsat has a constellation of geosynchronous communications satellites. Iridium uses a constellation of 66 Low Earth Orbit satellites to provide complete global coverage (including all ocean regions and both poles) with real-time coverage. Automatic Identification System – AIS is an IMO supported technology – provides low cost dual terrestrial and long-range satellite maritime data communications. It offers a base level of VMS functionality with global coverage at the lowest cost. Argos uses low Earth orbit European and US satellites in polar orbit, which is an especially appropriate orbit for vessels operating in high latitudes. Skymate uses Orbcomm LEO satellites, which is optimized for machine-to-machine communications, potentially at lower cost than voice-capable satellite systems. They operate in the VHF and UHF bands, and have demonstrated an AIS capability. Qualcomm provides access to the Iridium satellite systems. BlueTraker uses both GPRS and Iridium constellation to provide the biggest flexibility and the lowest communication costs. The BlueTraker is a stand-alone device fully integrated including the antennas, the communication modules and a back-up battery. It is also e-logbook