stations around the globe. In July 2014, ORBCOMM launched the first 6 OG2 satellites aboard a SpaceX Falcon 9 rocket from Cape Canaveral, Florida. Each OG2 satellite carries an AIS receiver payload. All 6 OG2 satellites were successfully deployed into orbit and started sending telemetry to ORBCOMM soon after launch. In December 2015, the company launched 11 additional AIS-enabled OG2 satellites aboard the SpaceX Falcon 9 rocket. This dedicated launch marked ORBCOMM's second and final OG2 mission to complete its next-generation satellite constellation. Compared to its current OG1 satellites, ORBCOMM's OG2 satellites are designed for faster message delivery, larger message sizes and better coverage at higher latitudes, while increasing network capacity. In August 2017, Spire Global Inc. released an API that delivers S-AIS data enhanced with machine learning (Vessels and Predict) backed by its 40+ constellation of nano-satellites. Correlation of data sources Correlating optical and radar imagery with S-AIS signatures enables the end-user to rapidly identify all types of vessel. A great strength of S-AIS is the ease with which it can be correlated with additional information from other sources such as radar, optical, ESM, and more SAR related tools such as GMDSS SARSAT and AMVER. Satellite-based radar and other sources can contribute to maritime surveillance by detecting all vessels in specific maritime areas of interest, a particularly useful attribute when trying to co-ordinate a long-range rescue effort or when dealing with VTS issues. VHF Data Exchange System Due to its growing use over time, in some coastal areas—e.g., the Singapore Strait, China's megaports, parts of Japan—there are so many vessels that the performance of AIS has been affected. As traffic density goes up, the system's range goes down, and the frequency of updates becomes more random. For this reason VHF Data Exchange System (VDES) has been developed: it will operate on additional new frequencies and will use them more efficiently, enabling thirty-two times as much bandwidth for secure communications and e-navigation. VDES is defined in ITU M.2092. Applications The original purpose of AIS was solely collision avoidance but many other applications have since developed and continue to be developed. AIS is currently used for: Collision avoidance AIS was developed by the IMO technical committees as a technology to avoid collisions among large vessels at sea that are not within range of shore-based systems. The technology identifies every vessel individually, along with its specific position and movements, enabling a virtual