AIS Data Methodology

Oceanbolt’s algorithms are based on AIS data (Automatic Identification System) that captures information about vessels' position.

Oceanbolt collects raw AIS data from third-party data providers using:

satellite networks
terrestrial networks
vessel-mounted AIS receivers

Consuming and processing AIS Data

The AIS feeds received are the highest resolution NMEA messages and Oceanbolt maintains a set of proprietary algorithms for cleaning the signals (e.g. matching IMO number with MMSI number) before applying our vessel-centric tracking algorithms.

A raw AIS data stream contains two types of information:

dynamic data about a vessel’s location, speed, and direction
static voyage-related information such as destination, ETA, and draught

The dynamic information is automatically emitted by the vessel, while the static information is manually entered by the crew onboard the vessel. Oceanbolt has built a proprietary algorithm that cleans and merges these two data streams to minimize noise.

Processing frequency

Oceanbolt’s algorithms work in a streaming (rather than batch-processing) fashion. This ensures that every time an AIS message is received by Oceanbolt’s backend, it is processed and the related events form the basis for ongoing and historical voyages. Read about Oceanbolt’s cargo tracking methodology section for more information.

AIS Coverage

With the highest resolution coverage of AIS data, Oceanbolt achieves coverage of circa 98% of all IMO numbers on a daily basis. Specific AIS coverage statistics can be found on the Oceanbolt platform. Most of the 2% of vessels that are missing on a daily basis will be far away from shore (e.g. in the middle of the Pacific Ocean), where limited operational or economically relevant activity will typically take place. Oceanbolt maintains the latest observed position of vessels until the next position is observed to provide a complete view of the fleet with every vessel represented every day.

Fleet Growth Statistics from AIS

We build fleet growth statistics from empirically observed AIS data. When new vessels are delivered, their AIS stream goes live, and when vessels are scrapped, their AIS stream goes permanently offline (Oceanbolt has a logic for removing scrapped vessels).