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Điều khoản Logistics AIS(Automatic Identification System)

Ngày đăng kíMAY 22, 2024

AIS(Automatic Identification System)
The logistics industry, a cornerstone of global commerce, is continually evolving with the integration of advanced technologies, and one such pivotal innovation is the Automatic Identification System (AIS). Originally developed to enhance maritime safety, AIS has transcended its initial purpose to become a crucial tool in the broader logistics sector. This system enables the automatic tracking of vessels through electronic data exchange with other nearby ships, AIS base stations, and satellites. It not only improves ocean navigation and safety by providing real-time locations of ships but also optimizes shipping routes and enhances cargo tracking capabilities. As we delve deeper into the functionalities and advantages of AIS in this blog, and how it facilitates seamless ocean logistics.
  1. 1) What is AIS?

    The Automatic Identification System (AIS) plays a crucial role in maritime safety and compliance, mandated by the International Maritime Organization (IMO) under SOLAS (Safety of Life at Sea) regulation V/19. This regulation specifies the types of navigational equipment ships must carry, tailored according to the type of ship. In a pivotal decision in 2000, the IMO revised this chapter to include the requirement for all ships to be equipped with AIS transponders that can automatically transmit vital information such as position, identification, and other details both to other ships and to coastal authorities.

    Specifically, the AIS requirement applies to all ships of 300 gross tonnage and upwards on international voyages, cargo ships of 500 gross tonnage and upwards not on international voyages, and all passenger ships regardless of size. This requirement took full effect by December 31, 2004, marking a significant milestone in maritime navigation safety protocols.

    Moreover, ships equipped with AIS are required to maintain the system in operation continuously, except in cases where international agreements, rules, or standards allow for the withholding of navigational information for security or other reasons. Exceptions to this mandate can be made by a flag State, which may exempt certain ships from carrying AIS.

    To ensure the effectiveness and reliability of AIS, performance standards were established as early as 1998. This regulatory framework not only enhances safety but also supports efficient maritime traffic management by ensuring seamless communication and tracking of vessels globally.

    The Automatic Identification System (AIS) is mandated to fulfill several critical functions in maritime safety and navigation, according to SOLAS regulation V/19. AIS systems are required to:

    1. Provide Vital Information
    AIS must automatically transmit important details such as the ship’s identity, type, position, course, speed, navigational status, and other safety-related information. This information must be sent to appropriately equipped shore stations, other ships, and aircraft, facilitating a comprehensive awareness of maritime activities in real-time.

    2. Receive Information
    AIS systems are also required to automatically receive similar information from other vessels equipped with AIS, ensuring that ships are mutually aware of each other's positions and movements.

    3. Monitor and Track Ships
    AIS helps in monitoring and tracking the movements of ships, enhancing the capability of maritime authorities and ship operators to manage traffic and respond to potential navigational threats more effectively.

    4. Data Exchange with Shore-Based Facilities
    AIS facilitates the exchange of navigational data with shore-based facilities, which is essential for port operations, traffic management, and maritime safety enforcement.

    The dissemination of AIS data has raised significant security concerns. At the seventy-ninth session in December 2004, the Maritime Safety Committee (MSC) of the International Maritime Organization highlighted potential risks associated with the public availability of AIS-generated data. The MSC expressed concerns that publishing AIS data on the world wide web, or elsewhere, could compromise the safety and security of both ships and port facilities.

    An image of ships carrying containers on the ocean. (Source: Firefly, Adobe)
  2. 2) How does AIS work?

    The Automatic Identification System (AIS) is a sophisticated maritime navigation safety tool that utilizes VHF radio and GPS technology to facilitate the automatic exchange of navigational information among ships and coastal stations. Here's how AIS operates in a step-by-step explanation:

    1. Position and Navigation Data Collection
    Each vessel equipped with an AIS transponder has a built-in GPS receiver. This GPS receiver determines the ship's exact position, speed, and course.

    2. Data Compilation
    The position and navigation data collected via GPS are then automatically combined with additional navigational information, such as the vessel's identity, type, and navigational status. This combination forms a comprehensive data set that represents the vessel’s current state and intent.

    3. Automatic Communication
    This compiled data is automatically transmitted at regular intervals via VHF radio signals from the vessel’s AIS transponder. There is no need for manual input from the crew for this data exchange, making it a seamless process.

    4. Reception by Other Vessels and Coastal Stations
    Nearby ships equipped with AIS and coastal stations receive this data. Each receiver has its own AIS transponder that can capture information from any other AIS-equipped vessel within VHF range.

    5. Display on Navigation Systems
    The received AIS data can be fed into a variety of display systems, such as chart plotters or PC-based charting software. These systems use the data to create a live, graphical display of maritime traffic in the vicinity, similar to a radar display.

    6. Enhancement of Radar Systems
    Although AIS operates independently of radar, it can be used to enhance radar systems. For vessels that are already equipped with radar, AIS data can provide additional information that might not be visible on radar, such as vessel identity and navigational status. Furthermore, because VHF radio waves can travel around bends and over obstacles, AIS can offer better coverage than radar in certain geographical conditions, improving overall navigational awareness.

    In summary, AIS enhances maritime safety by ensuring that ships are continually aware of each other’s positions and movements, thereby helping to prevent collisions and allowing for more informed decision-making on the water.

    Illustration of ships at sea connected by an automatic identification system. (Source: Firefly, Adobe)
  3. 3) AIS Types

    AIS transponders come in two main classes—Class A and Class B—each designed for different types of vessels and with varying functionalities. Here’s a breakdown of the differences between these classes: Class A Transponders Class A transponders are mandatory for larger vessels as outlined by international maritime regulations. They are typically required on:

    Ships of 300 gross tonnage and upwards engaged on international voyages.

    Cargo ships of 500 gross tonnage and upwards not engaged on international voyages.

    All passenger ships, regardless of size.


    Higher Broadcasting Frequency: Class A transponders transmit data every 2 to 10 seconds while the ship is moving and every 3 minutes while at anchor.

    More Comprehensive Data: They provide detailed information about the vessel, including position, course, speed, navigational status, and other safety-related information.

    Higher Power Output: This allows for a larger range of signal transmission, typically up to 20-30 nautical miles.

    Integration with Other Navigational Tools: Class A devices are integrated with external navigational sensors and shipborne navigational displays, offering advanced data interfacing capabilities.

    Best Suited For:

    Commercial shipping vessels

    Cruise liners

    Defense vessels


    Class B Transponders Class B transponders are designed for smaller vessels not covered by the mandates that require Class A transponders. They are used by:

    Lower Broadcasting Frequency: Class B transponders transmit data every 30 seconds when underway and every 3 minutes when at anchor.

    Less Detailed Information: While still providing essential information like position, course, and speed, Class B transponders transmit fewer details compared to Class A.

    Lower Power Output: This results in a shorter transmission range, generally about 5-10 nautical miles.

    Simplified Integration: Class B devices are typically easier to install and integrate with standard marine electronic equipment, making them more user-friendly for smaller vessel operators.

    Best Suited For:

    Leisure vessels

    Small fishing boats

    Non-international journey commercial vessels

    In summary, Class A transponders are designed for larger, commercial and passenger vessels requiring detailed navigational data for safety and compliance, while Class B transponders cater to smaller, non-commercial vessels needing basic navigational aids. Each class provides critical safety benefits appropriate to the needs and operational contexts of different types of maritime activity.

    Image of a ship carrying containers at sea (Source: Firefly, Adobe)
  4. 4) Considerations

    Indeed, gaps in AIS (Automatic Identification System) transmissions don't necessarily imply illicit activities or deliberate tampering. AIS is a robust tool designed to enhance maritime safety by providing real-time location and navigational data of vessels. However, there are several benign reasons why AIS signals might temporarily disappear, which are important for mariners and analysts to understand:

    Common Reasons for AIS Gaps

    Poor Coverage: AIS relies on terrestrial stations and satellites to pick up signals from ships. In areas where the network of stations is sparse or satellites have less frequent revisits, signals might not be captured consistently. This is common in remote areas or the high seas.

    Signal Collision: In heavily trafficked areas, such as busy ports or popular maritime routes, the VHF frequencies used by AIS can become congested. This can lead to signal collisions where multiple AIS transmissions interfere with each other, similar to the difficulty of making a mobile phone call in a crowded area.

    Weather Conditions: Severe weather can affect the reliability of AIS transmissions. High seas, heavy rain, or strong winds might disrupt the signal transmission or reception capabilities of AIS equipment.

    GPS Jamming: Although less common, GPS jamming can occur, which disrupts the GPS signals that AIS devices rely on to determine a vessel's position. This can be due to environmental factors, technical malfunctions, or intentional interference.

    Importance of AIS and Limitations
    While AIS is an invaluable tool for enhancing maritime safety through improved situational awareness, it should not be the sole source of information for navigation or collision avoidance. The system complements other navigational aids like radar, visual sightings, and navigational charts. Reliance solely on AIS can be misleading, especially if the data is incomplete or temporarily unavailable.

    Best Practices for Navigators

    Cross-Verification: Mariners should use AIS in conjunction with other navigational tools and sensors to verify and supplement the information received from AIS.

    Situational Awareness: Continuous monitoring of the surroundings through visual and radar observations remains crucial, especially in situations where AIS data might be incomplete or missing.

    Training and Experience: Understanding the limitations and proper use of AIS is essential for all maritime personnel. Training should emphasize that while AIS enhances navigational capabilities, it does not replace the critical judgment and decision-making skills of the ship’s crew.

    In summary, AIS gaps are often caused by technical or environmental factors and do not necessarily indicate wrongdoing. Mariners should be aware of these gaps and not rely exclusively on AIS for navigational decisions, continuing to apply comprehensive maritime skills and tools for safe navigation.

    Illustration of ships at sea connected by an automatic identification system. (Source: Firefly, Adobe)
  5. The transformation of AIS (Automatic Identification System) from a fundamental collision avoidance tool to a critical element in global supply chain management. As AIS technology is adopted more broadly across different vessel types, and as satellite coverage and data integration improve, AIS is set to revolutionize how shipments are tracked from origin to destination.

    Key Points for Future Development in AIS Utilization:

    Enhanced Satellite AIS Coverage: Improving satellite coverage to ensure more consistent and global AIS data availability will help in monitoring vessels in the most remote areas of the world’s oceans, filling current gaps in coverage.

    Integration with Other Data Sources: By synchronizing AIS data with other maritime data systems, stakeholders can gain a holistic view of maritime operations, enhancing decision-making processes and operational efficiencies.

    Addressing Data Quality Issues: Efforts must be made to enhance the accuracy, timeliness, and completeness of AIS data. This involves not only technological advancements but also adherence to data transmission standards and regulations.

    Promoting Information Sharing: Encouraging an environment where data is freely shared among shippers, carriers, and regulatory bodies can mitigate risks and enhance transparency within global supply chains.

    Development of Advanced Analytics: Leveraging technologies like machine learning, blockchain, and IoT sensors in conjunction with AIS data can lead to more sophisticated analysis and forecasting tools, thereby enhancing risk management and operational predictability.

    The evolution of AIS is pivotal for the future of maritime logistics. As part of a broader suite of digital transformation tools, AIS can provide unprecedented insights and efficiencies in shipping and supply chain management. For shippers, carriers, and technology providers, the focus should be on collaboration to refine data quality, expand capabilities, and ultimately, drive a new era of logistic transparency and efficiency. The integration of AIS with emerging technologies promises to foster a new level of supply chain intelligence, making it a cornerstone of global trade facilitation and security.