Difference between revisions of "AIS-Decoding"

Revision as of 08:02, 12 October 2025

This paper focuses on NON Position-Report (1,2,3,18,19) / Static-Data (5/24) messages.

AIS-Decoders

Ais Decoder

• https://arundaleais.github.io/docs/ais/ais_decoder.html (WIN)

gpsdecode

• https://gpsd.gitlab.io/gpsd/gpsdecode.html
• nc 153.44.253.27 5631 | gpsdecode | grep '"type":8'

{"class":"AIS","device":"stdin","type":8,"repeat":0,"mmsi":257057800,"scaled":true,
"dac":200,"fid":10,"vin":"00000000","length":215,"beam":60,"shiptype":8440,"shiptype_text":"Illegal ship type value.",
"hazard":5,"hazard_text":"Unknown","draught":0,"loaded":0,"loaded_text":"N/A (default)",
"speed_q":false,"course_q":false,"heading_q":false}

{"class":"AIS","device":"stdin","type":8,"repeat":0,"mmsi":215349000,"scaled":true,"dac":1,"fid":27,"linkage":90,"sender":0,"rtype":5,"rtype_text":"Ship route plan","start":"00-00T24:60Z","duration":262143,"waypoints":[{"lon":7.107972,"lat":62.844255},{"lon":7.112132,"lat":62.848032}]}

{"class":"AIS","device":"stdin","type":8,"repeat":0,"mmsi":215349000,"scaled":true,"dac":1,"fid":29,"linkage":90,"text":"LESSREMMAN - ELNES (VIA RORVIK; OUTSIDE) CAPT YURI"}

• nc ssia-ais.erau.edu 4000 | gpsdecode | grep -e '"type":8' -e '"type":27'

{"class":"AIS","device":"stdin","type":27,"repeat":0,"mmsi":368429323,"scaled":true,"status":"Not defined","accuracy":true,"lon":-81.0,"lat":29.2,"speed":0,"course":511,"raim":true,"gnss":false}

{"class":"AIS","device":"stdin","type":8,"repeat":0,"mmsi":369493715,"scaled":true,"dac":366,"fid":56,"data":"256:a83746ce99bb9edbd3eebb88bb7dcecba01df41d94f9397136c0c97eb4af8d69"}

{"class":"AIS","device":"stdin","type":8,"repeat":0,"mmsi":369493715,"scaled":true,"dac":366,"fid":57,"data":"512:bf68e50cc47b8ae14771ed1a0c075bfb60f82bb9ffec80211e4aad32b4edac38b33a6b4280f403d0dff4069a452f9cd51dfc44285226e53d7f337377f15829d6"}

missing/problems

• Text Telegram does not decode!

{"class":"AIS","device":"stdin","type":6,"repeat":0,"mmsi":538007497,"scaled":true,"seqno":1,"dest_mmsi":212848000,"retransmit":false,"dac":1,"fid":0,"data":"96:8040494e05054d48120d612e"}

• also valid, 'Illegal ship type' decoded! see https://unece.org/fileadmin/DAM/trans/doc/2013/sc3wp3/ECE-TRANS-SC3-WP3-2013-05e.pdf

{"class":"AIS","device":"stdin","type":8,"repeat":0,"mmsi":257303700,"scaled":true,"dac":200,"fid":10,"vin":"00000000","length":114,"beam":36,"shiptype":8450,"shiptype_text":"Illegal ship type value.","hazard":5,"hazard_text":"Unknown","draught":150,"loaded":0,"loaded_text":"N/A (default)","speed_q":false,"course_q":false,"heading_q":false}

• does not decode!

{"class":"AIS","device":"stdin","type":8,"repeat":0,"mmsi":257605000,"scaled":true,"dac":265,"fid":1,"data":"512:02017cf22f19aa2bc00f83af410ade2bc2dffbf6bff7822bc50fd3bbbffee02bc00f9874c049812bc140019c3ffd542bc0a017a6fee9842bc0787ea28bd27600"}

Maritec online AIS decoder

• https://www.maritec.co.za/aisvdmvdodecoding

pyais

• https://github.com/M0r13n/pyais
• pipx install pyais
• pipx ensurepath
• nc 153.44.253.27 5631 | ais-decode --json | grep '"msg_type": 8'

missing/problems

• poor Msg:8 decoding. Only DAC:200 FI:10

{"msg_type": 8, "repeat": 0, "mmsi": 257057800, "dac": 200, "fid": 10, "vin": "00000000", "length": 21.5, "beam": 6.0, "shiptype": 8440, "hazard": 5, draught": 0.0, "loaded": 0, "speed_q": false, "course_q": false, "heading_q": false}

{"msg_type": 8, "repeat": 0, "mmsi": 215349000, "dac": 1, "fid": 27, "data": "FwFAGPP//3ggjnij9kTwQREIR+t9QIGPWI/RpYEAV0kfnN4B/oNCP0lbA/56ZH7oMAfMqQkAPXgPnOUSBujgIEAnJCF1QEOc0Uhdt0CLKQCQxYXBGjYZIXqkAkLbgkK4VwS3FHSHEE4JngLpEMz8"}

{"msg_type": 8, "repeat": 0, "mmsi": 215349000, "dac": 1, "fid": 29, "data": "FwUw4VOC2BYVIQEyChYkGAdIlCnI"}

others

• https://github.com/tbsalling/aismessages
• https://github.com/bcl/aisparser
• https://github.com/schwehr/libais
• https://github.com/dma-ais/AisLib

aisdecode

• https://github.com/madpsy/aisdecode/
• ./aisdecode-linux-amd64 -log-all-decodes decoded

AIS-catcher

• input: https://docs.aiscatcher.org/configuration/input/tcp/
• output: https://docs.aiscatcher.org/configuration/output/console/
• web view: https://docs.aiscatcher.org/configuration/output/web-viewer/
• AIS-catcher -t txt://153.44.253.27:5631 -o 5 -N 8101 GEOJSON false MESSAGE true REALTIME false

Papers

• https://gpsd.gitlab.io/gpsd/AIVDM.html
• https://www.e-navigation.nl/system-messages
• https://www.e-navigation.nl/asm/ais
• https://arundaleais.github.io/docs/ais/ais_message_types.html
• https://arundaleais.github.io/docs/ais/ais_decoder_binary.html

NMEA Examples

Samples are taken from AIS-Sources

Message type 1 (out of scope)

• https://www.e-navigation.nl/content/position-report

Message type 2 (out of scope)

• https://www.e-navigation.nl/content/position-report-0

Message type 3 (out of scope)

• https://www.e-navigation.nl/content/position-report-1

Message type 4

• https://www.e-navigation.nl/content/base-station-report

Message type 5 (out of scope)

• https://www.e-navigation.nl/content/ship-static-and-voyage-related-data

Message type 6

• https://www.e-navigation.nl/content/addressed-binary-message

DAC:0

• 6/0/54: !AIVDM,1,1,,,6@28nOP0R=Wr03H9q=6e2000,0*7F

DAC:1

• 6/1/0: !BSVDM,1,1,4,B,633`PP1:wRqP040004<d,0*09
  • https://www.e-navigation.nl/content/text-using-6-bit-ascii
• 6/1/2: !AIVDM,1,1,,A,6h2E3MECnED00480J00000000000,0*5E
  • https://www.e-navigation.nl/content/interrogation-specified-fms-within-iai-branch
• 6/1/3: !AIVDM,1,1,,A,6h2E:p<u:nj204<0@00000000000,0*78
  • https://www.e-navigation.nl/content/capability-interrogation-0
• 6/1/4: !AIVDM,1,1,,A,638fgJ00UBf204@0@2000020000002000000000,2*27
  • https://www.e-navigation.nl/content/capability-reply-0
• 6/1/40: !AIVDM,1,1,,A,63aGrPP0U@oD06P000,4*1B
  • https://www.e-navigation.nl/content/number-persons-board-0

DAC:200

• 6/200/3: !AIVDM,1,1,,A,602E3TprE>Mv<P<j00,4*4C

DAC:232

• 6/232/1: !AIVDM,1,1,,A,63P:`4l0SJP@>P7g6PGIGSjPJ0,4*4E

DAC:235

• 6/235/10: !AIVDM,1,1,,,6>jaws@00004>da7P000000,2*4A
• 6/235/10: !BSVDM,1,1,,A,6>jHDwh00000>db@P000010,2*55
  • https://www.e-navigation.nl/content/aids-navigation-monitoring-data

DAC:440

• 6/440/40 !AIVDM,1,1,,A,603l90P0u2@8KRPh<=m8ADQcf@:e9N@PwP0wP008000080000000,0*75

DAC:990

• 6/990/3 !AIVDM,1,1,,A,6>l4vWh0??VQurKe1?au8=jp1hU@@00010,4*1D

Message type 7

• https://www.e-navigation.nl/content/binary-acknowledge
• !AIVDM,1,1,,A,7b8Bp1N2BknWRf0,4*24

Message type 8

• https://www.e-navigation.nl/content/binary-broadcast-message

DAC:1

• 8/1/16: !AIVDM,1,1,,A,802At?00D000qFap02:lA0b@?3fw0001<:iFP2:rf0cCGp0w00,4*5E
  • https://www.e-navigation.nl/content/vts-targets-targets-derived-means-other-ais
• 8/1/27: !BSVDM,1,1,,B,83=Go200Fih7h1Sh00080000000000,4*0E
  • https://www.e-navigation.nl/content/route-information-0
• 8/1/29: !AIVDM,1,1,,,83t`?I@0G@:?>G1?6600,0*0B
• 8/1/29: !BSVDM,1,1,,A,83ku;wh0GAQB?7>1>PeP6B54B9;CD14P,0*10
• 8/1/29: !AIVDM,2,1,6,,83buRF00G@1jhjmemPC3B?2IPC1>4CPD?P?ED5B81B2?EBP7B51DPI1B=?ED8,0*6B !AIVDM,2,2,6,,0,4*65
  • https://www.e-navigation.nl/content/text-description-0
• 8/1/31: !AIVDM,1,1,,,8vjHWT@0Gh0TN1N>vCC0Qi0lnPAL`GFigwl?wnSwe7wvlOwwsAwwnSGmwvh0,0*57
• 8/1/31: !AIVDM,1,1,,,8vjHWR00Gh05I1NBtkC0gwvlFR06EuOwgrVWwnSwe7wvlOwwsAwwnSGmwvh0,0*09
• 8/1/31: !AIVDM,1,1,,,8vjHWQ00GwwJlAN>g;C0gwvlFR06EuOwgquOwnSwe7wvlOwwsAwwnSGmwvh0,0*7F
• 8/1/31: !AIVDM,1,1,,,8vjHWPh0Gh0f1aN<:SC0wwvlFR06EuOwgreGwnSwe7wvlOwwsAwwnSGmwvh0,0*13
• 8/1/31: !AIVDM,2,1,7,A,8>jHE700Gwr7HIVSwS;JPwtqFPC3b2o;gwl>0Dt1R9@1`b0PSb0>:gB;wvv00000,0*77 !AIVDM,2,2,7,A,001,0*20
  • https://www.e-navigation.nl/content/meteorological-and-hydrographic-data

DAC:103

• 8/103/56: !AIVDM,1,1,,,8000000Iv?JmFqtQ<6WvDdm4HwwhalETq?2Gq:wQ03,4*55

DAC:200

• 8/200/25: !AIVDM,1,1,,,8@1tMD@j6B2`00498L74Uc8I4WIp,0*38
  • https://www.e-navigation.nl/content/present-bridge-clearance
• 8/200/26: !AIVDM,1,1,,,8@1tMD@j6P2`0L04m00000000000,0*68
  • https://www.e-navigation.nl/content/water-level-message-2
• 8/200/55: !AIVDM,1,1,,,835NdJPj=hD000000000000,2*10
  • https://www.e-navigation.nl/content/number-persons-board-1

DAC:265

• 8/265/1: !BSVDM,2,1,3,B,83mme212@@5bNT`dbVhUP?wrgH0<IBF000ip0:U=9H?00QO03VpUP0wuI<0G,0*1C !BSVDM,2,2,3,B,;2F1sws2@0l79H000;m00q`UP5c6h8eWod0,2*27
  • https://www.e-navigation.nl/content/route-message-0

DAC:316

• 8/316/0: !AIVDM,2,1,2,A,8000wQA?0000AkDp3@@i3kPC180TRA1iH=L;,0*6C !AIVDM,2,2,2,A,8888880,2*26
  • FI:0=?
• 8/316/1/3: !AIVDM,2,1,6,,8030osA?0@>U:jPPPB38jnsuPTt6m2Oa@02U:jPPPB38knsvSTt0DRnA@02U:,0*55 !AIVDM,2,2,6,,jPPPB38nnsvA4so@Soi@02U:jPPP<<F<nsUvTr?DT?0@00,2*4C
  • https://www.e-navigation.nl/content/water-level-message
• 8/316/2/1: !AIVDM,2,1,7,,8h3Owj1?0P6U:eC<CO<hknsuq4t54P2222222220<DhTp7BVp004hLtl60MD5,0*23 !AIVDM,2,2,7,,8@T4qBbTP0HD@E84j0dUH4hTsBbg00,2*35
  • Lockage Order Message (Seaway)
• 8/316/2/2:
  • Estimated Lock Times Message (Seaway)
• 8/316/32/1: !AIVDM,1,1,,,8030osA?80440@0,2*44
  • https://www.e-navigation.nl/content/version-message-seaway

DAC:366

• 8/366/56: !AIVDM,1,1,,A,85PH6liKf6Q7K<r9gds1gL<QTaI;JIo2nl4dvMdmQehw06ElF7ba,0*49
  • https://www.e-navigation.nl/content/position-report-payload
• 8/366/57: !AIVDM,2,1,0,A,85PH6MiKfI>IpPLg>bvJf?8GTtIr1CQirolq>IQglM<sIhDlpEA2P`otmk=7,0*5A !AIVDM,2,2,7,A,88888888880,2*23
  • https://www.e-navigation.nl/content/static-data-payload

DAC:755

• 8/755/43: !AIVDM,1,1,,B,8i2r`;Btrpk:58a34`8,1*38

Message type 9

• https://www.e-navigation.nl/content/standard-search-and-rescue-aircraft-position-report
• !AIVDM,1,1,,A,91b55vRCQvOo4PLLww<3cGh20@Br,0*79
• !AIVDM,1,1,,B,91b55vRCQvOo25fM003Cc5P200SE,0*51

Message type 10

• https://www.e-navigation.nl/content/coordinated-universal-time-and-date-inquiry
• !AIVDM,1,1,,B,:3mrMf0o9r40,0*08
• !AIVDM,1,1,,B,:8152F@q@7r0,0*53

Message type 11

• https://www.e-navigation.nl/content/coordinated-universal-time-and-date-response
• !AIVDM,1,1,,,;025>TAvVT;>lPtmTbN3h9O02000,0*73

Message type 12

• https://www.e-navigation.nl/content/addressed-safety-related-message
• <

Message type 13

• https://www.e-navigation.nl/content/safety-related-acknowledge
• !AIVDM,1,1,,A,=7@Ri<k12pI3A8H78,1*36

Message type 14

• https://www.e-navigation.nl/content/safety-related-broadcast-message
• !BSVDM,1,1,,B,>>M5?si<59B1@E=@,0*5A
• !BSVDM,1,1,,B,>>OS:i@lt:04=@UHF20,2*33

Message type 15

• https://www.e-navigation.nl/content/interrogation
• !AIVDM,1,1,,,?3:4?B0rG3D4D00,2*18

Message type 16

• https://www.e-navigation.nl/content/assigned-mode-command
• !AIVDM,1,1,,B,@6STUk004lQ206bCKNOBAb6SJ@5s,0*74

Message type 17

• https://www.e-navigation.nl/content/global-navigation-satellite-system-broadcast-binary-message
• !AIVDM,2,1,7,,A@1tMD@9Ddpb80@05NIn1@0005P7wq;v1Pl0Q@0q3P2B08@?wvP0LAGw9?uu5,0*4F !AIVDM,2,2,7,,gwP03dN08;w4:bb,0*73

Message type 18 (out of scope)

• https://www.e-navigation.nl/content/standard-class-b-equipment-position-report

Message type 19 (out of scope)

• https://www.e-navigation.nl/content/extended-class-b-equipment-position-report

Message type 20

• https://www.e-navigation.nl/content/data-link-management-message
• !AIVDM,1,1,,,D01tMD@FLNfr<`f017@O6D8PN00,2*1A
• !AIVDM,1,1,,,D05J8jP?TN?`fpNfp0,4*6E
• !AIVDM,1,1,,,D030osj<TvfqsINfqt1N9ItaN96,2*21
• !AIVDM,1,1,,,D030ow03Hg6D>e?6DF8g6D0,2*19
• !AIVDM,1,1,,A,D7OertARHNfp00O6EPlNfqmtO6D,2*05
• !AIVDM,1,1,,,D02Q:dQRpNfp00N000,4*7F
• !AIVDM,1,1,,,D01vI7iGtS6EHpS6EI<S6D0,2*2E

Message type 21

• https://www.e-navigation.nl/content/aids-navigation-report
• !AIVDM,1,1,,,E>jN6L<Sc;pP000000000000000@7ctH>fwT000003iP10,4*09
• !AIVDM,1,1,,,ENjNi4pV7ab@294V64W3h84`2P0@=3n;?R3t@00003vN10,4*61
• !AIVDM,1,1,,,ENjAaDG2d:9@9ba@Fh24`bRh22hOmq?2:OvK@<7hGkP>2S1EPCU1KChr<JAh,0*6A
• !AIVDM,1,1,,,ENjOsr0tg@6a9Qh;2W4QRP000000L;g4<wpI000000N010,4*68
• !AIVDM,1,1,,,ENk`snv`5@@@@@@@@@@@@@@@@@@=Hbqv;fPcH00003vP000,2*48
• !AIVDM,1,1,,,E>nlfRNQRW:97h=3h0W:2`:Ra:7erKB:n6Veh00003W010,4*77 !AIVDM,2,2,6,,jPPPB38nnsvA4so@Soi@02U:jPPP<<F<nsUvTr?DT?0@00,2*4C
• !AIVDM,1,1,,B,ENk`sE<Hph@@@@@@@@@@@@@@@@@=7UIQ8889h00003vP000,2*36
• !AIVDM,1,1,,A,E>lt;w9QRc11W00000000000000Dten:n39q@00003vP10,4*43
• !AIVDM,1,1,,,ENj7=GrPV0R=40gQ0W5PP000000A0@2w<HI=000003v000,4*35
• !AIVDM,1,1,,,ENj7=IaWR0ah;0a70hI00000000104rL<Fe0000003v000,4*31
• !AIVDM,1,1,,,ENj7=IIWR0ah;0a70hHP00000000wu3N<Fqth00003v000,4*34
• !AIVDM,1,1,,,ENj7=JqWR0ah2VTW2P0000000000wo`V<=kUP00003v000,4*3E

Message type 22

• https://www.e-navigation.nl/content/channel-management
• !AIVDM,1,1,,,F030osj2N2P6aoabhe47C6L20000,0*44

Message type 23

• https://www.e-navigation.nl/content/group-assignment-command
• !AIVDM,1,1,,,G01tMD0:08pu0?lQhg600000;00,2*59
• !AIVDM,1,1,,,Gh2E3502qdv@054isVb00000000,2*05

Message type 24 (out of scope)

• https://www.e-navigation.nl/content/static-data-report

Message type 25

• https://www.e-navigation.nl/content/single-slot-binary-message
• !AIVDM,1,1,,,I8LgAM@00000k=6DDLil`0O5;K02,0*30
• !AIVDM,1,1,,,I8Lg9gh00000k=6DDLifD0O4JF02,0*19
• !AIVDM,1,1,,,I8LgAM@00000k=6DNLila0O5;I02,0*39
• !AIVDM,1,1,,B,I5Hfm`iWdrBeAk4,1*6A

Message type 26

• https://www.e-navigation.nl/content/multiple-slot-binary-message-communications-state
• J

Message type 27

• https://www.e-navigation.nl/content/long-range-automatic-identification-system-broadcast-message
• !AIVDM,1,1,,B,K5OG92wu2Cj8E0Ot,0*37
• !AIVDM,1,1,,B,KoOis@Sm4`uL40Ot,0*78