Worldwide AIS Message 12’s were collected via AISHUB’s raw data feed and entered into MYSQL. AIS Message 12 is an addressed Safety-Related Message.
This means we get the Senders and Addressee’s MMSI. This creates a kind of social infra structure that was looked into via Gephi. 12200 AIS Message 12 were collected and MMSi’s and Names from Message 5 and 24, so one can link MMSI to names. As names have to be hand entered into the AIS transceiver not all MMSI have names, or the identifying Message 5 or 24 were not yet received in AISHUB’s raw data feed.
First a Graph was made with Gephi selecting an inner join on all messages in MYSQL that had perfect (that means names were available for sender and recipient) logging.
We can see there are clusters between ships. Given, that AIS is largely a line of site VHF radio message, information islands obviously exist in worldwide data collection. Most inter ship connections with Message 12 are unidirectional and not looping (few are answered).
Concentrating on one node network we see that the HOEGH YOKOHAMA (MMSI:564734000, Callsign: S6TV, IMO: 9185451) , a Singapore registered Vehicle Carrier was the centre of a communication node network involving several ships.
Going back to our logged messages we find out, that the Hoegh Yokohama was running a test on how many vessels, were responding to a Message named “Test”. We can see that only the Nysted Maersk and the Am Tubarao responded. In the data we see that the Hoegh Yokohama did this on two dates and that the Nysted Maersk also communicated with the Mette Maersk with a similar message named “Test”. The Don Carlos another Singapore registered Vehicle Carrier then created a small sub network to pass the Test message on.
While this might not be a significant revelation, we can though see how communications between ships can be retraced and visualised, like social network interactions and bank account transfers.
If we take all Message 12 into a graph, we see that there are 3 few manned VTS in Asia and mostly Japan that dominate the graph and use Message 12 heavily to direct messages to specific ships. These messages mostly just say wither that the recipients entered an area or warns them that they co aground.
A vessel traffic service (VTS) is a marine traffic monitoring system established by harbour or port authorities, similar to air traffic control for aircraft.
These are: VTS 4310505 in Kobe Japan an MMSI of 999028 (possibly an AtoN [Aid to Navigation]) that automatically sends Messages if one leaves or enters the Yantai VTS area [no link found], VTS 4310703 on a Mountain Top close to the East China Sea, VTS 4310704 that controls the KANMON MARTIS , a small waterway between the Japanese Islands and VTS 4310606 also on the Japanese Coast.
Then there is an active VTS south of Cyprus (VTS 2129940) that has an isolated node network and SINGAPORE VTIS that sends collision course warnings to ships. Interestingly some of these VTS are not easy to find in a standard web search.
It’s also interesting that seemingly, besides Cyprus the main traffic here is in the Asian part of the Globe.