EAIS_IDD_v5_FINAL.pdf

Distribution Statement A: Approved for Public Release. Distribution is Unlimited.

Encrypted Automatic Identification System (EAIS) Interface Design Description (IDD)

25 July 2016

Submitted by:

M. W. Parsons, GS-13, USCG Date

Core Technologies Navigation Branch (CT-N1) System Engineer

Approved by:

M. V. Kempe, LCDR Date

Core Technologies Navigation Sensors (CT-N2) Section Chief

Approved by:

T. M. McClellan, CDR Date

Core Technologies Navigation (CT-N) Branch Chief

EAIS Interface Design Description Version 5 25 July 2016

Record of Changes

Change# Date Title or Brief Description Entered By

Original 04 Jun 14 C3CEN EAIS IDD v1.0 LT A.R. Reckley v2 27 Oct 14 Added IEC 61993-2 to references; clarified para 3.1.6.1; added para 3.3.1.2; added para

3.3.4.1.1; added para 5.3.1; added SOTDMA to msg 26 Comm State in Annex 2 para 2.1;

deleted “Text” from para 3.23.1.3

M. W. Parsons v3 N/A Version not released v4 N/A Version not released v5 25 Jul 16 Added FIDs 9-37 and complied with revision to USCG EAIS VDL Standard.

LCDR M. Kempe

Table of Contents

1. Scope 1

2. References 2

3. Interface Description 3

Annex 1 4

Annex 2 5

Annex 3 91

Annex 4 93

Annex 5 99

Appendix 1 100

Appendix 2 103

Appendix 3 108

Appendix 4 111

Appendix 5 112

EAIS IDD v5 Page 1

1. Scope

1.1. Identification

This Interface Design Description (IDD) specifies the interface characteristics of an Encrypted Automatic Identification System (EAIS) which meets Coast Guard requirements for Sensitive But Unclassified (SBU) Tactical Information Exchange and Display System (STEDS) and Blue Force Tracking (BFT).

1.2. Policy

This IDD meets COMDT (CG-761) operational requirements for STEDS and BFT.

1.3. System Overview

Coast Guard EAIS consists of an EAIS Transponder and an EAIS Presentation Interface (PI).

The EAIS Presentation Interface is typically an Electronic Chart System (ECS) or Electronic Chart Display Information System (ECDIS).

EAIS IDD v5 Page 2

2. References

Name/Number Version Date Title eNav Requirements

Mar 2012 eNav Coast Guard Requirements v1.2

COMD (G-OCC-1)

LTR 2000

Jul 2005 Operational Requirements for SBU Tactical Information Exchange and Display System

(STEDS)

IEC 61174 Mar 2010 Specifications for Chart Content and Display Aspects of ECDIS, Edition 6.0, IEC 61993-2 Ed.2 Oct 2012 Class A shipborne equipment of the AIS - Operational and performance requirements

NMEA 0183 Jun 2012 Standard for Interfacing Marine Electronic Devices (Ver.4.10)

NMEA 2000 Jan 2013 Edition 3.00 Includes the following documents:

Main Document Version 1.210 Appendix A Version 1.200 (Application Layer -included in Appendix B) Appendix B Version 2.000 (Database of Messages) Appendix C Version 1.200 (Certification Criteria and Test Methods) Appendix D Version 1.210 (Application Notes) Appendix E ISO 11783-3 Data Link Layer Appendix F ISO 11783-5 Network Management Appendix G ISO 11898 Controller Area Network Appendix H (3rd Party Applications w/ NMEA 2000 Certified 3rd Party Gateway)

ITU-R M. 1371-5 Feb 2014 "Technical Characteristics for a Universal Shipborne Automatic Identification System Using Time Division Multiple Access"

ITU-R M.1084 Mar 2012 Interim solutions for improved efficiency in the use of the band 156-174 MHz by stations in the maritime mobile service

TIA-102.AACA-A Sep 2014 Project25 Digital Radio Over-The-Air-Rekeying (OTAR) Messages and Procedures

EAIS IDD v5 Page 3

3. Interface Description

Annex 1 contains a technical description of the eAIS VDL when the AIS messages 25 & 26 are used to transport the Sensitive But Unclassified (SBU) Tactical Information Exchange and Display System (STEDS) Application Specific Messages (ASM).

Annex 1 is based on International Telecommunication Union (lTU) standard ITU-R M.1371-5.

Annex 2 contains the listing of the ASMs used with this IDD.

Annex 3 contains a technical description of NMEA-0183 messages required to integrate an

EAIS capable AIS Transponder with an EAIS capable Presentation Interface (PI) and vice versa. Proprietary NMEA-0183 messages are required for complete integration.

Please see the NMEA-0183 standard for NMEA-0183 messages.

Annex 4 contains a technical description of proprietary NMEA-2000/NMEA OneNet PGN messages required to integrate an EAIS capable AIS transponder with an EAIS capable Presentation Interface (PI) and vice versa. Standard NMEA-2000/NMEA OneNet PGN messages are used in the integration, but are not defined by this document. Please see the NMEA-2000/NMEA OneNet PGN standard for NMEA- 2000/NMEA OneNet PGN messages.

Annex 5 contains OTAR requirements for the PI.

Appendix 1 contains a listing of the asset types used with this IDD.

Appendix 2 contains an explanation of Search Pattern Definitions, along with nomenclature and designations.

Appendix 3 contains a listing of vessel, aircraft and submarine Target Descriptions for use with

Target of Interest ASMs.

Appendix 4 contains an explanation of the OTAR Primitive Field Descriptions Appendix 5 contains a listing of Key Name Codes used with OTAR Key names.

EAIS IDD v5 Page 4

ANNEX 1

EAIS Transponder Modes of Operation

Normal

When in this mode of operation, the AIS transponder defaults to operate in Autonomous & Continuous mode, unless switched to Assigned or Polled mode. The transponder sends and receives AIS messages and EAIS messages.

Receive-Only

When in this mode of operation the AIS transponder does not transmit any AIS messages, regardless of any commands received from base stations or interrogations from other vessels. The transponder operates exclusively on normal AIS frequencies and does not respond to base station or digital selective calling commands to change frequencies. The transponder receives AIS messages and EAIS messages, but transmits nothing (maintaining radio silence).

Restricted

When in this mode of operation the AIS transponder only transmits EAIS messages, while no non-EAIS messages are sent. The transponder shall operate exclusively on normal AIS frequencies and shall not respond to base station or digital selective calling commands to change frequencies. The transponder continues to receive AIS messages and EAIS messages.

CRC Checksum Computation

When computing the 16-bit CRC checksum for the encrypted ASMs, this VDL utilizes the “reflected table driven” implementation, as described in RFC 1662 (Std 51), found at http://www.armware.dk/RFC/rfc/rfc1662.html. RFC 1662 describes the standards for High-level Data Control Link (HDCL). Appendix C.2 of that document lists the code to implement the “reflected table driven” algorithm.

The RFC 1662 code implements the 16-bit CRC as specified below.

Width: 16 bits

Polynomial: 1021

Initial CRC value (seed): FFFF

Input bytes (8 bits) are processed with bit 0 being treated as the most significant bit (MOB) and bit 7 being treated as the least significant bit

Final CRC is XORed with: FFFF

Output CRC (16 bits) is reflected.

The lower eight bits of the CRC are swapped with the higher eight bits of the CRC

The CRC is applied using all bits from the Function Identifier field up to but not including the CRC field;

this will be a multiple of 128-bits minus 16 bits.

EAIS IDD v5 Page 5

ANNEX 2

Legend:

In the message format tables in this chapter, red shading indicates the encrypted portions of the ASM, olive indicates message data governed by the Project25 OTAR guidance, and lavender shading indicates optional message data for various OTAR fields.

2.1 Message Acknowledgement

DAC: 366 FI: 9 (Encrypted) 10 (Unencrypted)

Published: 12 May 2016 Version: 0

Summary of changes:

Version 0:

This is an RTCM compliant update of the FID 2 message listed in the Oct 2014 EAIS IDD.

There are AIS Message 25 and 8 variants of this message. The encrypted message 8 is not implemented.

2.1.1 Introduction

This Message 25 payload is used to acknowledge reception of another message such as an Addressed TOI or Addressed Overlay.

2.1.2 Usage Notes

This message can be used to acknowledge receipt of other ASMs, and differs from AIS message 6 because it requires operator initiation.

Receipt of addressed as well as broadcast messages can be acknowledged.

Acknowledgement linkage back to the original message is based upon source MMSI, source FI, and source Message Linkage ID.

The AIS Message 25 variant should be used to acknowledge AIS Message 25/26 ASMs.

EAIS IDD v5 Page 6

2.1.3 Message 25, FID 9 (Encrypted) Format

Encrypted Message Acknowledgement (Message 25, Broadcast)

Parameter # of Bits

Description

St an da rd

M es sa ge

H ea de r

Message ID 6 Identifier for Message 25; always 25.

Repeat Indicator 2 Indicates how many times a message has been repeated. 0 – 3; 0 = default; 3 = do not repeat any more. Set to 0 (default).

Source MMSI 30 MMSI number of source station. Varies according to the transmitter ID.

Destination Indicator 1 0 = broadcast (no Destination ID field) 1 = Addressed (30 bit Destination ID field). Set to 0 (broadcast).

Binary Data Flag 1 0 = unstructured binary data (no Application Identifier bits used) 1 = binary data coded as defined by the 16-bit AI. Set to zero (unstructured).

Destination ID 0 MMSI number of destination station. Not used.

Spare 0 Not used.

B in ar y

A pp lic at io n

D at a (e nc ry pt ed

Function Identifier 6 Function identifier. Set to 9.

Version 3 Sequential number used to indicate the message version in steps of 1.

0 = test message = default; 1 – 7 = message version.

Set to zero.

Original Message Source 30 MMSI of the source of the message being acknowledged.

Original Message DAC 10 DAC of the message to be acknowledged. Set to 0 if no DAC (AIS message 25/26 messages).

Original Message FI 6 Functional Identifier of message being acknowledged. 0 – 63.

Original Message MLID 10 MLID of the source message to be acknowledged.

UTC Hour 5 UTC Hour of ACK.

0 – 23; 24 = UTC hour not available = default; 25 - 31 = reserved.

UTC Min 6 UTC Minute of ACK.

0 – 59; 60 = UTC minute not available = default; 61 - 63 (reserved for future use).

UTC Sec 6 UTC Second of ACK.

0 – 59; 60 = UTC second not available = default; 61-63 (reserved for future use).

Spare 30 Not used. Set to zero.

Checksum 16 16-bit CRC calculated as per EAIS Specification

Total bits 168 1 Slot Binary Message

EAIS IDD v5 Page 7

2.1.4 Message 8, FID 10 (Un-encrypted) Format

Unencrypted Message Acknowledgement (Message 8)

Description

St an da rd

M es sa ge

H ea de r

Message ID 6 Identifier for Message 8; always 8.

Repeat Indicator 2 Indicates how many times a message has been repeated. 0 – 3; 0 = default; 3 = do not repeat any more. Set to zero (default).

Source MMSI 30 MMSI number of source station. Varies according to the transmitter ID.

Spare 2 Not used. Set to zero.

B in ar y

D at a

Designated Area Code 10 Designated area code (DAC). This code is based on the maritime identification digits (MID). Set to 366 (US).

Function Identifier 6 Function identifier. Set to 10.

A pp lic at io n

D at a (u n-en cr yp te d)

Version 3 Sequential number used to indicate the message version in steps of 1.

0 = test message = default; 1 – 7 = message version. Set to zero.

Original Message Source 30 MMSI of the source of the message being acknowledged.

Original Message DAC 10 DAC of the message to be acknowledged. Set to 0 if no DAC (AIS message 25/26 messages).

Original Message FI 6 Functional Identifier of message being acknowledged. 0 – 63.

Original Message MLID 10 MLID of the source message to be acknowledged.

UTC Hour 5 UTC Hour of ACK.

0 – 23; 24 = UTC hour not available = default; 25 - 31 = reserved.

UTC Min 6 UTC Minute of ACK.

0 – 59; 60 = UTC minute not available = default; 61 - 63 (reserved for future use).

UTC Sec 6 UTC Second of ACK.

0 – 59; 60 = UTC second not available = default; 61-63 (reserved for future use).

Total bits 132 1 Slot Binary Message

EAIS IDD v5 Page 8

2.2 Situation Report (SITREP) for Vessels and Aircraft

DAC: 366 FI: 11 (Encrypted)

Published: 12 May 2016 Version: 0

Summary of changes:

Version 0:

This is an RTCM compliant update of the FID 0 Message 25 listed in the Oct 2014 EAIS IDD. It also replaces the DAC 366, FI 56 Position Report from the same document.

There are AIS Message 25 and 8 variants of this message, but only Message 25 is implemented.

2.2.1 Introduction

The Situation Report Message is used to send the equivalent information to AIS Message 1 but removes less essential data to compress message size.

2.2.2 Usage Notes

This same report can be used for both vessels and aircraft.

Note: Only aircraft engaged in SAR (using SAR transponder) may transmit AIS.

The position report shall be transmitted once every 30 seconds when the unit has registered a speed over ground (SOG) of less than 3 knots for more than 3 minutes and once every 15 seconds when SOG is 3 knots or greater. Aircraft should transmit at 10-second intervals.

2.2.3 Message 25 Encrypted Format

Encrypted Situation Report (Message 25, Broadcast)

Description

St an da rd

M es sa ge

H ea de r

Message ID 6 Identifier for Message 25; always 25.

Repeat Indicator 2 Indicates how many times a message has been repeated. 0 – 3; 0 = default; 3 = do not repeat any more. Set to zero (default).

Source MMSI 30 MMSI number of source station. Varies according to the transmitter ID.

Destination Indicator 1 0 = broadcast (no Destination ID field) 1 = Addressed (30 bit Destination ID field). Set to zero (broadcast).

Binary Data Flag 1 0 = unstructured binary data (no Application Identifier bits used) 1 = binary data coded as defined by the 16-bit AI. Set to zero (unstructured).

Destination ID 0 MMSI number of destination station. Not used.

Spare 0 Not used.

EAIS IDD v5 Page 9

B in ar y A pp lic at io n D at a

(e nc ry pt ed

Function Identifier 6 Function identifier. Set to 11.

Version 3 Sequential number used to indicate the message version in steps of 1.

0 = test message = default; 1 – 7 = message version. Set to zero.

Time of Position - UTC Min 6 UTC Minute of the position.

0 – 59; 60 = UTC minute not available = default; 61 - 63 (reserved for future use).

Time of Position - UTC Sec 3 UTC Seconds of the position; 10-second resolution.

0 = 0 sec; 1 =10 sec; 2 = 20 sec; 3 = 30 sec; 4 = 40 sec; 5 = 50 sec; 6 = unknown = default; 7 = (reserved for future use).

Craft Flag 1 Indicates whether report is from a vessel or aircraft.

0 = vessel = default; 1 = aircraft.

Longitude 28 Longitude in 1/10,000 min (±180 degrees, East = positive, West = negative.

181 degrees = not available = default). Negative in 2’s complement.

Latitude 27 Latitude in 1/10,000 min (±90 degrees, North = positive, South = negative, 91 degrees = not available = default). Negative in 2’s complement.

Altitude 12 Altitude above sea level in 1m increments. Set to 0 for vessels.

0-4,000 m; 4001 = 4,001 m or higher; 4,002 = unknown = default.

COG 12

Course over ground in 1/10° increments.

0-359.9 degrees; 3,600 = not available = default; 3,601 – 4095 = reserved.

SOG 10

Speed over ground. Scale dependent on value of craft flag.

Aircraft: 0 – 1000 kts (1 kt increments); 1001 = 1001 kts or higher; 1002 = not available = default; 1003 – 1023 = reserved.

Vessel: 0 – 100.0 kts (0.1 kt increments); 1001 = 100.1 kts or higher; 1002 = not available = default; 1003 – 1023 = reserved.

Operational Status 4

Operational status of the craft reporting.

0 = unknown = default 1 = ops normal 2 = on scene as directed 3 = returning to port/land 4 = awaiting instructions 5 = Bravo at home port 6 = Bravo at port other than home 7 = Charlie, homeport 8 = Charlie, in repair 9-15 reserved.

EAIS IDD v5 Page 10

2.3 Static Data Report

DAC: 366 FI: 12 (Encrypted)

Published: 12 May 2016 Version: 0

Summary of changes:

Version 0:

This is an RTCM compliant update of the FID 0 message listed in the Oct 2014 EAIS IDD. It also replaces the DAC 366, FI 57 Static Data Report from the same document.

There are AIS Message 25 and 8 variants of this message, but only Message 25 is implemented.

2.3.1 Introduction

The Static Data Message is used to send the equivalent information to AIS Message 5 but removes less essential data to compress message size.

2.3.2 Usage Notes

The FID 11 static data report shall be transmitted once every 6 minutes.

The data is matched by MMSI to the corresponding FID 10 message to provide additional information.

EAIS IDD v5 Page 11

2.3.3 Message 25 Encrypted Format

Static Data (Message 25, Broadcast, Encrypted)

Description

St an da rd

M es sa ge

H ea de r

Message ID 6 Identifier for Message 25; always 25.

Repeat Indicator 2 Indicates how many times a message has been repeated. 0 – 3; 0 = default; 3 = do not repeat any more. Set to zero (default).

Source MMSI 30 MMSI number of source station. Varies according to the transmitter ID.

Destination Indicator 1 0 = broadcast (no Destination ID field) 1 = Addressed (30 bit Destination ID field). Set to zero (broadcast).

Binary Data Flag 1 0 = unstructured binary data (no Application Identifier bits used) 1 = binary data coded as defined by the 16-bit AI. Set to zero (unstructured).

Destination ID 0 MMSI number of destination station. Not used.

Spare 0 Not used.

B in ar y

A pp lic at io n

D at a (e nc ry pt ed

Function Identifier 6 Function identifier. Set to 12.

Version 3 Sequential number used to indicate the message version in steps of 1.

0 = test message = default; 1 – 7 = message version. Set to zero.

Asset Name 90 Maximum 15 characters 6-bit ASCII as per ITU 1371.

"@@@@@@@@@@@@@@@@" = not available = default.

The Name should be as shown on the station radio license.

Asset Type 10 Asset Type as per Appendix 1 of this VDL.

DTE 1

Data terminal equipment (DTE) ready.

0 = available, 1 = not available = default.

Spare 2 Not used. Set to zero.

EAIS IDD v5 Page 12

5.4 Search Pattern Report

DAC: 366 FI: 13 (Encrypted) 14 (Unencrypted)

Published: 12 May 2016 Version: 0

Summary of changes:

Version 0:

This is an RTCM compliant update of the FID 2 message listed in the Oct 2014 EAIS IDD. The FID was changed to avoid confusion with ASMs used by the Saint Lawrence Seaway Corp.

There are AIS Message 25 and 8 variants of this message, but the encrypted Message 8 isnt implemented.

5.4.1 Introduction

The Search Pattern Report (SPR) communicates a search pattern from the SAR Mission Coordinator (SMC) to a Search UNIT (SRU) (either to transmit a pattern for action or to cancel a pattern) or from a SRU to the SMC (reporting acceptance or completion). Search plan nomenclature is included for reference in Appendix 2 of this IDD.

5.4.2 Usage Notes

The Search execution status is controlled by the Search Pattern Status field. A State

Diagram is shown in Figure 5 with the execution flow as follows:

o The pattern is initially sent from the MC to the action SRU with the Status set as 0

(direction to execute a plan).

o The SRU should respond with either:

Status set as 0 to indicate that the pattern was received and will be started

(identical pattern parameters).

Status set to 7 to say the pattern cannot be executed.

o If the SRU sends a status of 7 the MC needs to send a new pattern (followed up with communications between the MC and SRU to discuss WHY the pattern cannot be executed).

o Once the search plan is started the SRU shall send a message with status 1 with the time and position fields updated to reflect the actual commence search time and position.

o Once the pattern is complete the SRU should send the Search pattern report with a status of 2 and with the time and position fields updated to reflect time and position of completion.

o If the SRU needs to abort the plan prior to completion a message with status=3 should be sent with the time and position fields updated to reflect time and position when aborted plan.

o If the SMC wants to cancel a SAR pattern prior to completion then the message is sent with status = 3.

EAIS IDD v5 Page 13

Figure 1: SAR Plan Message State Diagram

The Message Linkage ID can be used to link additional text (e.g., a separate Linked Text message). However, the same source MMSI needs to be included in both the SPR and the Linked Text Message (LTM). This could be used to communicate a SAR pattern designation or additional notes about the pattern or search object.

A message version number is encoded as part of the message; if the received version number is different than what the display system has been programmed for, then the charting system should alert the user to the difference.

All headings are in degrees true.

All positions are in WGS 84 Datum.

If less than 10 characters, the remainder of the Case ID parameter should be filled with

“@” characters (set bits to 0); but, not shown on the presentation.

For the expanding square search the track spacing should equal the first leg length; to ensure this is true the value should be specified in the first leg length field and track spacing field set to 0.

For the Message 26 version, the 20 bits Communications State are added by the transmitter if transmission is initiated by a BBM sentence.

EAIS IDD v5 Page 14

5.4.2.1 Expanding Square Search (SS) Parameters

An expanding square search pattern uses the following parameters:

CSP

Initial heading Track spacing Direction of turns (L/R)

All turns are 90°, typically to starboard. Each even turn, increase the distance of the leg by 1 track space. See Figure 1 within Appendix 2 of this VDL. For this pattern track spacing and initial leg length are the same and both fields should be set to the same value.

5.4.2.2 Sector Search (VS) Parameters

A sector search pattern uses the following parameters:

CSP

Initial heading Leg length Number of legs (defined as the equal-length segments)

All turns are 120° to starboard, and all legs are of equal length. The legs are the equal length segments (from CSP to radius of the circle). It takes 9 equal length legs to complete one VS pattern (less than 9 legs can be specified if the full pattern is not desired). After completing 9 equal length legs (back to the CSP) the pattern can be repeated with a new initial heading 30° to starboard of the initial. So if the number of legs specified is greater than 9, after 9 legs, rotate the pattern 30° to the right and continue. After 18 legs, rotate the pattern another 30° to the right. See Figure 2 within Appendix 2 of this VDL.

5.4.2.3 Parallel Search (PS) Parameters

A parallel search pattern uses the following parameters:

CSP

Initial direction Leg length Track spacing First turn (L/R)

All turns are 90° – 2 turns in same direction then switch direction. Cross leg lengths are equal to track spacing. Go leg length, turn go track space, turn same direction go leg length, turn opposite direction go track space, turn same, etc. See Figure 3 within Appendix 2 of this VDL.

5.4.2.4 Creeping Line Search (CS) Parameters

The creeping line search is the same as the parallel search except that the search legs are oriented along the minor axis of the search area vice the major axis.

EAIS IDD v5 Page 15

5.4.3 Message 26, FID 13 (Encrypted) Format

SAR Pattern Report (Message 26, Broadcast, Encrypted)

Description

St an da rd

M es sa ge

H ea de r

Message ID 6 Identifier for Message 26; always 26.

Repeat Indicator 2 Indicates how many times a message has been repeated. 0 – 3; 0 = default; 3 = do not repeat any more. Set to zero (default).

Source MMSI 30 MMSI number of source station. Varies according to the transmitter ID.

Destination Indicator 1 0 = Broadcast (no Destination ID field used) 1 = Addressed (Destination ID uses 30 data bits for MMSI) Set to 0, broadcast.

Binary Data Flag 1 0 = unstructured binary data (no Application Identifier bits used); 1 = binary data coded as defined by using the16-bit Application identifier.

Set to 0, unstructured.

A pp lic at io n

D at a (e nc ry pt ed

Function Identifier 6 Function identifier. Set to 13.

Version 3 Sequential number used to indicate the message version in steps of 1.

0 = test message = default; 1 – 7 = message version. Set to zero.

Message Linkage ID 10

Identifier for the SAR Pattern Report. This number uniquely identifies a search pattern sent from a given SMC (MMSI) and is used to connect additional information with the search. Source MMSI and this ID uniquely identify the event.

Set to 0-1023 by message originator; 0 = not available = default.

Pattern Type 3 Type of search pattern:

0 = Expanding Square (SS) = default; 1 = Sector (VS); 2 = Parallel Line (PS); 3 = Creeping Line (CS); 4 – 7 = reserved.

Search Pattern Status 3

Code From MC From Action SRU

0 Search plan to be executed Search plan to be executed (concur w/ mission plan, and will take FORAC)

1 Reserved Search plan started (time and search position updated to actual CST and CSP)

2 Reserved Search plan completed. (time and point updated to reflect completion time and last position)

Search plan cancelled by

SMC

Search plan aborted (time and point updated to reflect aborted time and position)

Directions to divert from search plan at this position, execute new search plan.

Indicates unit has diverted from search plan at this position

Direction to resume search plan at this position

Indicates the unit has resumed search plan at this position

6 Reserved Reserved for future use 7 Reserved Unable to execute search plan

EAIS IDD v5 Page 16

A pp lic at io n

D at a (e nc ry pt ed

R ef er en ce T im e UTC Day 5 UTC Day

1 – 31; 0 = UTC day not available = default.

UTC Hour 5 UTC Hour.

0 – 23; 24 = UTC hour not available = default; 25 - 31 = reserved.

UTC Min 6 UTC Minute.

0 – 59; 60 = UTC minute not available = default; 61 - 63 (reserved for future use).

Action SRU MMSI 30 MMSI of the Action SRU. This varies according to the MMSI of the desired unit. 0 = unknown = default;

Case ID Number 30

Case ID. Maximum 5 characters 6-bit ASCII as defined in ITU 1371-5, Table 47.

“@@@@@” = not available = default.

If less than 5 characters, the remainder of the parameter should be filled with “@” characters (set bits to 0); but, not shown on the presentation.

Se ar ch P oi nt

Longitude 25 Longitude in 1/1000 minute. (±180°) East = positive (as per 2’s complement); West = negative (as per 2’s complement); 181° = not available = default.

Latitude 24 Latitude in 1/1,000 minute (±90°) North = positive (as per 2’s complement); South = negative (as per 2’s complement); 91° = not available = default.

Initial Heading 9 Direction of the first leg.

0 – 359 degrees; 360 = not specified = default;

361 – 510 = reserved; 511 = not to be used.

First Leg Length 12

Length of the first leg (lengths of succeeding legs depend upon the type of pattern) in 0.1 NM increments.

0 = not specified = default; 0.1 – 400.0 NM;

4001-4094 = reserved; 4095 = not to be used.

No. of Legs 10 Total number of legs (search and cross) to execute.

0 = not specified = default; 1 – 1000 legs;

1001-1022 = reserved; 1023 = not to be used.

Track Spacing 9 Track spacing in 0.1 NM increments.

0 = not specified = default; 0.1 – 50.0 NM;

501 – 510 = reserved; 511 – not to be used.

First Turn Direction 1 Direction of first turn.

0 = port; 1 = starboard = default.

Search Altitude 7 Altitude for search pattern in 50 ft increments.

0 = sea level; 50 – 6000 ft; 121 = not specified = default; 122 – 127 = reserved.

Search Speed 9 Speed to execute the search pattern in 1kt increments.

0 = not specified = default; 1 – 500 kts;

501 – 510 = reserved; 511 – not to be used.

Search Area Width 11 Total width of search area in tenths of NM 0 = unknown = default; 0.1 – 200.0 NM; 2001-2047 reserved.

Search Area Length 11 Total length of search area in tenths of NM 0 = unknown = default; 0.1 – 200.0 NM; 2001-2047 reserved.

Spare 11 Zero padding for AES encryption byte boundaries. Set to zero.

EAIS IDD v5 Page 17

Fo ot er

Spare 4 Four extra bits added to ensure the message ends on a byte boundary.

Set to zero.

Communications State Selector 1

0 = SOTDMA communication state follows 1 = ITDMA communication state follows

Communications State 19 SOTDMA communication state (see ITU 1371-5 § 3.3.7.2.1, Annex 2), if communication state selector flag is set to 0, or ITDMA communication state (§ 3.3.7.3.2, Annex 2), if communication state selector flag is set to 1.

Total bits 320 2 Slot Binary Message

EAIS IDD v5 Page 18

5.4.3 Message 8, FID 14 (Unencrypted) Format

Unencrypted SAR Pattern Report (Message 8, Broadcast)

Description

St an da rd

M es de r

Message ID 6 Identifier for Message 8; always 8.

Repeat Indicator 2 Indicates how many times a message has been repeated. 0 – 3; 0 = default; 3 = do not repeat any more. Set to zero (default).

Source MMSI 30 MMSI number of source station. Varies according to the transmitter ID.

Spare 2 Not used. Set to zero.

B in ar y

D at a

Designated Area Code 10 Designated area code (DAC). This code is based on the maritime identification digits (MID). Set to 366 (US).

Function Identifier 6 Function identifier. Set to 14.

A pp lic at io n

D at a (u ne nc ry pt ed

Version 3 Sequential number used to indicate the message version in steps of 1.

0 = test message = default; 1 – 7 = message version. Set to zero.

Message Linkage ID 10

Identifier for the SAR Pattern Report. This number uniquely identifies a search pattern sent from a given SMC (MMSI) and is used to connect additional information with the search. Source MMSI and this ID uniquely identify the event.

Set to 0-1023 by message originator; 0 = not available = default.

Pattern Type 3 Type of search pattern:

0 = Expanding Square (SS) = default; 1 = Sector (VS); 2 = Parallel Line (PS); 3 = Creeping Line (CS); 4 – 7 = reserved.

Search Pattern Status 3

Code From MC From Action SRU

0 Search plan to be executed Search plan to be executed (concur w/ mission plan, and will take FORAC)

1 Reserved Search plan started (time and search position updated to actual CST and CSP)

2 Reserved Search plan completed. (time and point updated to reflect completion time and last position)

3 Search plan cancelled by

SMC

Search plan aborted (time and point updated to reflect aborted time and position)

Directions to divert from search plan at this position, execute new search plan.

Indicates unit has diverted from search plan at this position

Direction to resume search plan at this position

Indicates the unit has resumed search plan at this position

R ef er en ce T im e UTC Day 5

UTC Day 1 – 31; 0 = UTC day not available = default.

UTC Hour 5 UTC Hour.

0 – 23; 24 = UTC hour not available = default; 25 - 31 = reserved.

UTC Min 6 UTC Minute.

0 – 59; 60 = UTC minute not available = default; 61 - 63 (reserved for future use).

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Action SRU MMSI 30 MMSI of the Action SRU. This varies according to the MMSI of the desired unit. 0 = unknown = default;

Case ID Number 30

Case ID. Maximum 5 characters 6-bit ASCII as defined in ITU 1371-5, Table 47.

“@@@@@” = not available = default.

If less than 5 characters, the remainder of the parameter should be filled with “@” characters (set bits to 0); but, not shown on the presentation.

Se ar ch P

Longitude 25

East = positive (as per 2’s complement); West = negative (as per 2’s complement); 181° = not available = default.

Latitude 24 Latitude in 1/1,000 minute (±90°) North = positive (as per 2’s complement); South = negative (as per 2’s complement); 91° = not available = default.

Initial Heading 9 Direction of the first leg.

0 – 359 degrees; 360 = not specified = default;

361 – 510 = reserved; 511 = not to be used.

First Leg Length 12

Length of the first leg (lengths of succeeding legs depend upon the type of pattern) in 0.1 NM increments.

0 = not specified = default; 0.1 – 400.0 NM;

4001-4094 = reserved; 4095 = not to be used.

No. of Legs 10 Total number of legs (search and cross) to execute.

0 = not specified = default; 1 – 1000 legs;

1001-1022 = reserved; 1023 = not to be used.

Track Spacing 9 Track spacing in 0.1 NM increments.

0 = not specified = default; 0.1 – 50.0 NM;

501 – 510 = reserved; 511 – not to be used.

First Turn Direction 1 Direction of first turn.

0 = port; 1 = starboard = default.

Search Altitude 7 Altitude for search pattern in 50 ft increments.

0 = sea level; 50 – 6000 ft; 121 = not specified = default; 122 – 127 = reserved.

Search Speed 9 Speed to execute the search pattern in 1kt increments.

0 = not specified = default; 1 – 500 kts;

501 – 510 = reserved; 511 – not to be used.

Search Area Width 11 Total width of search area in tenths of NM 0 = unknown = default; 0.1 – 200.0 NM; 2001-2047 reserved.

Search Area Length 11 Total length of search area in tenths of NM 0 = unknown = default; 0.1 – 200.0 NM; 2001-2047 reserved.

Spare 1 Set to zero.

Total bits 280 2 Slot Binary Message

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5.5 Trackline Report

DAC: 366 FI: 15 (Encrypted) 16 (Unencrypted)

Published: 12 May 2016 Version: 0

Summary of changes:

Version 0:

This is an RTCM compliant update of the FID 3 message listed in the Oct 2014 EAIS IDD. The FID was changed to avoid confusion with previously published message definitions.

There are AIS Message 25 and 8 variants of this message, but the encrypted message 8 is not implemented.

5.5.1 Introduction

The Trackline Report (SPR) communicates a search pattern from the mission controller to a SRU (either to transmit a pattern for action or to cancel a pattern) or from a SRU to the MC (reporting acceptance or completion).

5.5.2 Usage Notes

The SAR execution status is controlled by the SAR Pattern Status field. A State Diagram is shown in Figure 5 with the execution flow as follows:

o The pattern is initially sent from the SMC to the action SRU with the Status set as 0

(direction to execute a plan).

o The SRU should respond with either:

Status set as 0 to indicate that the pattern was received and will be started

(identical pattern parameters).

Status set to 7 to say the pattern cannot be executed.

o If the SRU sends a status of 7 the SMC needs to send a new pattern (followed up with communications between the MC and SRU to discuss WHY the pattern cannot be executed).

o Once the search plan is started the SRU shall send a message with status 1 with the time and position fields updated to reflect the actual commence search time and position.

o Once the pattern is complete the SRU should send the SAR pattern report with a status of 2 and with the time and position fields updated to reflect time and position of completion.

o If the SRU needs to abort the plan prior to completion a message with status=3 should be sent with the time and position fields updated to reflect time and position when aborted plan.

o If the SMC wants to cancel a SAR pattern prior to completion then the message is sent with status of 3.

The Message Linkage ID can be used to link additional text (e.g., a separate Linked Text message). However, the same source MMSI needs to be included in both the SPR and the Linked Text Message (LTM). This could be used to communicate a SAR pattern designation or additional notes about the pattern or search object.

A message version number is encoded as part of the message; if the received version number is different than what the display system has been programmed for, then the charting system should alert the user to the difference.

Positions are in WGS 84 Datum.

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If less than 10 characters, the remainder of the SRU designation parameter should be filled with “@” characters (set bits to 0); but, not shown on the presentation.

To allow the SRU to transmit the message it should be kept to a maximum of 3 slots, which equates to a maximum of 7 additional waypoints for unencrypted and 6 for the encrypted version.

A trackline search pattern is specified by the waypoints (Lat/Long).

If pattern type is polygon then the track connects back to the CSP.

The Trackline Report is sent as several short message segments that need to be assembled by the recipient. The segments are identified by segment number and list the total number of segments (1 of 3, 2 of 3 etc.).

The first Trackline Report segment contains the information about the type of pattern and search parameters. All succeeding segments just contain waypoint information.

5.5.3 Message 26, FID 15 (Encrypted) Format

Encrypted Trackline Report Segment 1 (Message 26, Broadcast)

Description

St an da rd

M es sa ge

H ea de r Message ID 6 Identifier for Message 26; always 26.

Repeat Indicator 2 Indicates how many times a message has been repeated. 0 – 3; 0 = default; 3 = do not repeat any more. Set to zero (default).

Source MMSI 30 MMSI number of source station. Varies according to the transmitter ID.

Destination Indicator 1 0 = Broadcast (no Destination ID field used) 1 = Addressed (Destination ID uses 30 data bits for MMSI) Set to 0, broadcast.

Binary Data Flag 1 0 = unstructured binary data (no Application Identifier bits used); 1 = binary data coded as defined by using the16-bit Application identifier.

Set to 0, unstructured.

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Function Identifier 6 Function identifier. Set to 15.

Version 3 Sequential number used to indicate the message version in steps of 1.

0 = test message = default; 1 – 7 = message version. Set to zero.

Message Linkage ID 10

Identifier for the SAR Pattern Report. This number uniquely identifies a search pattern sent from a given SMC (MMSI) and is used to connect additional information with the search. Source MMSI and this ID uniquely identify the event.

Set to 0-1023 by message originator; 0 = not available = default.

Message Segment 5 Number of this message segment; sequential number. Recipient will need to receive all segments and put in order sequentially. 0 – 31. Set to 0.

Number of Segments 5 Total number of segments comprising the complete Trackline Report (Total = N+1). N = 0- 31.

Pattern Type 2 Type of search pattern:

0 = Trackline Search Pattern or route = default; 1 = Polygon; 2-3 = reserved.

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Search Pattern Status 3

Code From MC From Action SRU

0 Search plan to be executed Search plan to be executed (concur w/ mission plan, and will take FORAC)

1 Reserved Search plan started (time and search position updated to actual CST and CSP)

2 Reserved Search plan completed. (time and point updated to reflect completion time and last position)

Search plan cancelled by

SMC

Search plan aborted (time and point updated to reflect aborted time and position)

Directions to divert from search plan at this position, execute new search plan.

Indicates unit has diverted from search plan at this position

5 Direction to resume search plan at this position

Indicates the unit has resumed search plan at this position

R ef er en ce T im e UTC Day 5 UTC Day

1 – 31; 0 = UTC day not available = default.

UTC Hour 5 UTC Hour.

0 – 23; 24 = UTC hour not available = default; 25 - 31 = reserved.

UTC Min 6 UTC Minute.

0 – 59; 60 = UTC minute not available = default; 61 - 63 (reserved for future use).

Action SRU MMSI 30 MMSI of the Action SRU. This varies according to the MMSI of the desired unit. 0 = unknown = default;

Case ID Number 30

Case ID. Maximum 5 characters 6-bit ASCII as defined in ITU 1371-5, Table 47.

“@@@@@” = not available = default.

If less than 5 characters, the remainder of the parameter should be filled with “@” characters (set bits to 0); but, not shown on the presentation.

Se ar ch P

Longitude 28

East = positive (as per 2’s complement); West = negative (as per 2’s complement); 181° = not available = default.

Latitude 27 Latitude in 1/1,000 minute (±90°) North = positive (as per 2’s complement); South = negative (as per 2’s complement); 91° = not available = default.

Search Altitude 7 Altitude for search pattern in 50 ft increments.

0 = sea level; 50 – 6000 ft; 121 = not specified = default; 122 – 127 = reserved.

Search Speed 9 Speed to execute the search pattern in 1kt increments.

0 = not specified = default; 1 – 500 kts;

501 – 510 = reserved; 511 – not to be used.

Spare 59 Zero padding for AES encryption byte boundaries. Set to zero.

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Fo

Set to zero.

Communications State Selector 1

0 = SOTDMA communication state follows 1 = ITDMA communication state follows

Communications State 19 SOTDMA communication state (see ITU 1371-5 § 3.3.7.2.1, Annex 2), if communication state selector flag is set to 0, or ITDMA communication state (§ 3.3.7.3.2, Annex 2), if communication state selector flag is set to 1.

Encrypted Trackline Report Segment 2-32 (Message 26, Broadcast)

Description

St an da rd

M es sa ge

H ea de r

Message ID 6 Identifier for Message 26; always 26.

Repeat Indicator 2 Indicates how many times a message has been repeated. 0 – 3; 0 = default; 3 = do not repeat any more. Set to zero (default).

Source MMSI 30 MMSI number of source station. Varies according to the transmitter ID.

Destination Indicator 1 0 = Broadcast (no Destination ID field used) 1 = Addressed (Destination ID uses 30 data bits for MMSI) Set to 0, broadcast.

Binary Data Flag 1 0 = unstructured binary data (no Application Identifier bits used); 1 = binary data coded as defined by using the16-bit Application identifier.

Set to 0, unstructured.

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Function Identifier 6 Function identifier. Set to 15.

Version 3 Sequential number used to indicate the message version in steps of 1.

0 = test message = default; 1 – 7 = message version. Set to zero.

Message Linkage ID 10

Identifier for the SAR Pattern Report. This number uniquely identifies a search pattern sent from a given SMC (MMSI) and is used to connect additional information with the search. Source MMSI and this ID uniquely identify the event.

Set to 0-1023 by message originator; 0 = not available = default.

Message Segment 5 Number of this message segment; sequential number. Recipient will need to receive all segments and put in order sequentially. 0 – 31. Set to 0.

Number of Segments 5 Total number of segments comprising the complete Trackline Report (Total = N+1). N = 0- 31.

Se ar ch P

East = positive (as per 2’s complement); West = negative (as per 2’s complement); 181° = not available = default.

Latitude 27 Latitude in 1/1,000 minute (±90°) North = positive (as per 2’s complement); South = negative (as per 2’s complement); 91° = not available = default.

Search Altitude 7 Altitude for search pattern in 50 ft increments.

0 = sea level; 50 – 6000 ft; 121 = not specified = default; 122 – 127 = reserved.

Search Speed 9 Speed to execute the search pattern in 1kt increments.

0 = not specified = default; 1 – 500 kts;

501 – 510 = reserved; 511 – not to be used.

Spare 12 Zero padding for AES encryption byte boundaries. Set to zero.

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Fo

Set to zero.

Communications State Selector 1

0 = SOTDMA communication state follows 1 = ITDMA communication state follows

Communications State 19 SOTDMA communication state (see ITU 1371-5 § 3.3.7.2.1, Annex 2), if communication state selector flag is set to 0, or ITDMA communication state (§

Total bits 192 2 Slot Binary Message

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5.5.1 Message 8, FID 16 (Unencrypted) Format

Unencrypted Trackline Report Segment 1 (Message 8, Broadcast)

Description

St an da rd

M es de r

Message ID 6 Identifier for Message 8; always 8.

Repeat Indicator 2 Indicates how many times a message has been repeated. 0 – 3; 0 = default; 3 = do not repeat any more. Set to zero (default).

Source MMSI 30 MMSI number of source station. Varies according to the transmitter ID.

Spare 2 Not used. Set to zero.

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Designated Area Code 10 Designated area code (DAC). This code is based on the maritime identification digits (MID). Set to 366 (US).

Function Identifier 6 Function identifier. Set to 16.

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Version 3 Sequential number used to indicate the message version in steps of 1.

0 = test message = default; 1 – 7 = message version. Set to zero.

Message Linkage ID 10

Identifier for the SAR Pattern Report. This number uniquely identifies a search pattern sent from a given SMC (MMSI) and is used to connect additional information with the search. Source MMSI and this ID uniquely identify the event.

Set to 0-1023 by message originator; 0 = not available = default.

Message Segment 5 Number of this message segment; sequential number. Recipient will need to receive all segments and put in order sequentially. 0 – 31. Set to 0.

Number of Segments 5 Total number of segments comprising the complete Trackline Report (Total = N+1). N = 0- 31.

Pattern Type 2 Type of search pattern:

0 = Trackline Search Pattern or route = default; 1 = Polygon; 2-3 = reserved.

Search Pattern Status 3

Code From MC From Action SRU

0 Search plan to be executed Search plan to be executed (concur w/ mission plan, and will take FORAC)

1 Reserved Search plan started (time and search position updated to actual CST and CSP)

2 Reserved Search plan completed. (time and point updated to reflect completion time and last position)

3 Search plan cancelled by

SMC

Search plan aborted (time and point updated to reflect aborted time and position)

Directions to divert from search plan at this position, execute new search plan.

Indicates unit has diverted from search plan at this position

Direction to resume search plan at this position

Indicates the unit has resumed search plan at this position

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R ef er en ce T im e UTC Day 5 UTC Day

1 – 31; 0 = UTC day not available = default.

UTC Hour 5 UTC Hour.

0 – 23; 24 = UTC hour not available = default; 25 - 31 = reserved.

UTC Min 6 UTC Minute.

0 – 59; 60 = UTC minute not available = default; 61 - 63 (reserved for future use).

Action SRU MMSI 30 MMSI of the Action SRU. This varies according to the MMSI of the desired unit. 0 = unknown = default;

Case ID Number 30

Case ID. Maximum 5 characters 6-bit ASCII as defined in ITU 1371-5, Table 47.

“@@@@@” = not available = default.

If less than 5 characters, the remainder of the parameter should be filled with “@” characters (set bits to 0); but, not shown on the presentation.

Se ar ch P

East = positive (as per 2’s complement); West = negative (as per 2’s complement); 181° = not available = default.

Latitude 27 Latitude in 1/1,000 minute (±90°) North = positive (as per 2’s complement); South = negative (as per 2’s complement); 91° = not available = default.

Search Altitude 7 Altitude for search pattern in 50 ft increments.

0 = sea level; 50 – 6000 ft; 121 = not specified = default; 122 – 127 = reserved.

Search Speed 9 Speed to execute the search pattern in 1kt increments.

0 = not specified = default; 1 – 500 kts;

501 – 510 = reserved; 511 – not to be used.

Spare 1 Set to zero.

Total bits 232 2 Slot Binary Message

Unencrypted SAR Trackline Report Segment 2-32 (Message 8, Broadcast)

Description

St an da rd

M es de r

Message ID 6 Identifier for Message 8; always 8.

Repeat Indicator 2 Indicates how many times a message has been repeated. 0 – 3; 0 = default; 3 = do not repeat any more. Set to zero (default).

Source MMSI 30 MMSI number of source station. Varies according to the transmitter ID.

Spare 2 Not used. Set to zero.

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Designated Area Code 10 Designated area code (DAC). This code is based on the maritime identification digits (MID). Set to 366 (US).

Function Identifier 6 Function identifier. Set to 16.

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Version 3 Sequential number used to indicate the message version in steps of 1.

0 = test message = default; 1 – 7 = message version. Set to zero.

Message Linkage ID 10

Identifier for the SAR Pattern Report. This number uniquely identifies a search pattern sent from a given SMC (MMSI) and is used to connect additional information with the search. Source MMSI and this ID uniquely identify the event.

Set to 0-1023 by message originator; 0 = not available = default.

Message Segment 5 Number of this message segment; sequential number. Recipient will need to receive all segments and put in order sequentially.

1 – 31.

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Number of Segments 5 Total number of segments comprising the complete Trackline Report (Total = N+1). N = 0- 31.

Se ar ch P

East = positive (as per 2’s complement); West = negative (as per 2’s complement); 181° = not available = default.

Latitude 27 Latitude in 1/1,000 minute (±90°) North = positive (as per 2’s complement); South = negative (as per 2’s complement); 91° = not available = default.

Search Altitude 7 Altitude for search pattern in 50 ft increments.

0 = sea level; 50 – 6000 ft; 121 = not specified = default; 122 – 127 = reserved.

Search Speed 9 Speed to execute the search pattern in 1kt increments.

0 = not specified = default; 1 – 500 kts;

501 – 510 = reserved; 511 – not to be used.

Spare 2 Set to zero.

Total bits 152 1 Slot Binary Message

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5.6 Text Message

DAC: 366 FI: 17 (Encrypted)

Published: 12 May 2016 Version: 0

Summary of changes:

Version 0:

This is an RTCM compliant update of the FID 3 message listed in the Oct 2014 EAIS IDD. It also replaces the DAC 366 FID 55 message from the same document.

There are AIS Message 6, 8 and 26 variants of this message, but only message 26 is implemented.

5.6.1 Introduction

This Message is used to send encrypted text messages.

5.6.2 Usage Notes

The Message 26 Text Message format provides for both a broadcast and addressed text message. Message addressing, when required, shall be performed using the Destination Indicator and Destination ID fields inherent to the Message 26 structure.

The text may be up to 141 6-bit ASCII characters (up to 846 bits).

5.6.3 Message 26 Addressed Format

Encrypted Text Message (Message 26, Addressed)

Description

St an da rd

M es sa ge

H ea de r

Message ID 6 Identifier for Message 26; always 26.

Repeat Indicator 2 Indicates how many times a message has been repeated. 0 – 3; 0 = default; 3 = do not repeat any more. Set to zero (default).

Source MMSI 30 MMSI number of source station. Varies according to the transmitter ID.

Destination Indicator 1 0 = broadcast (no Destination ID field) 1 = Addressed (30 bit Destination ID field). Set to 1 (addressed).

Binary Data Flag 1 0 = unstructured binary data (no Application Identifier bits used) 1 = binary data coded as defined by the 16-bit AI. Set to zero (unstructured).

Destination ID 30 MMSI number of destination station. Not used.

Spare 2 Not used, Set to zero.

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Function Identifier 6 Function identifier. Set to 17.

Version 3 Sequential number used to indicate the message version in steps of 1.

0 = test message = default; 1 – 7 = message version. Set to zero.

Message Linkage ID 10

A source-specific running number, unique across all binary messages equipped with Message Linkage ID. Used to connect the additional information in this Text Message with another ASM. The Message Linkage ID and the source MMSI uniquely identify the sent message. 1 – 1,023; 0 = not available = default.

ACK Flag 1 Acknowledgement Flag; used to indicate…