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Software Quality Assurance In e-Navigation
Developing Standards to Harmonize Ship and Shore e-Navigation


Dr. Seojeong Lee

Dr. Lee Alexander

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e-Navigation is a current international initiative that is intended to facilitate the transition of maritime navigation into the digital era. Defined by the International Maritime Organization (IMO) as 'the harmonized collection, integration, exchange, presentation and analysis of maritime information onboard and ashore by electronic means to enhance birth-to-birth navigation and related services, for safety and security at sea and protection of the marine environment,' e-Navigation is not a new system but a concept of operation.

Three outcomes are envisioned by IMO. The first is that shipboard navigation systems will benefit from the integration of onboard ship sensors, supporting information, standard user interface, and a comprehensive system for managing guard zones and alerts. Core elements include high-integrity electronic positioning, use of electronic navigational charts, and an analysis capability to reduce human error. The second is that the management of vessel traffic and related services from shore will be enhanced through better provision, coordination and exchange of comprehensive data in formats that will be more easily understood and utilized. The third is a communications infrastructure designed to enable authorized seamless information transfer onboard ship, between ships, between ship and shore, and between shore authorities.

Realizing these goals will not be easy. In particular, there are some significant challenges associated with digital data and software quality, including the use of both existing and new forms of digital data and the software required to operate the various types of e-Navigation-related systems and equipment. Most likely, software-related issues will become a significant challenge for achieving harmonized shipborne and shore-based e-Navigation. For this to occur, an established means/process for software quality assurance (SQA) is needed.

Implementing e-Navigation will require connection and integration between existing onboard navigational systems, as well as shoreside equipment. Navigation and communications equipment must be able to reliably indicate that they are functioning correctly. If redundancy is being used to provide resilience, the system should be able to transfer automatically to an alternative source, and provide an appropriate indication to the user. In addition, information concerning the source and authenticity of the data, and the current software in use, will be needed.

When using increasingly complex systems, there is the expectation that there will be greater functional capability with no loss in reliability. However, the opposite result can often occur. One example of the importance of software quality assurance is the reported anomalies that have occurred with electronic chart display and information systems (ECDIS). Due to the complex nature of ECDIS, i.e., a mix of hardware, software, sensor inputs and data, the cause of the anomalies are not always apparent. However, software is usually a factor. As reported to IMO in 2011, the International Hydrographic Organization (IHO) expressed concern that there was no specific obligation for ship operators to keep software up-to-date for increasingly sophisticated computer-based systems. As a result, in 2012 IMO issued a draft Safety of Navigation Circular on 'Operating Anomalies Identified within ECDIS.' In addition, IMO is looking into developing a policy on the working-life validity of software-driven electronic navigation equipment.

ISO Standards
One way to achieve consistency and uniformity is to conform to relevant international standards. In particular, there are significant benefits when there is compliance with standards established by the International Organization for Standardization (ISO). ISO has adopted software quality standards for avionics, automobiles and medical equipment/devices.

Safety-critical systems are those in which defects could have a detrimental impact on humans, the environment or assets. Depending on software functionality requirements, these systems are expected to verify specific qualities, including reliability, availability, security and safety.

ISO has published several standards related to software quality with regard to product, development process and quality-in-use. ISO/IEC 9126-1 classifies software quality as a structured set of characteristics. Each quality characteristic and associated subcharacteristics (e.g., attributes) needs to be measured (i.e., metrics).

Reliability is a set of attributes that relate to the capability of software to maintain its level of performance under stated conditions for a given period of time. Usability is a set of attributes that describe the intended use, and that this use meets the needs of intended users. Efficiency is a set of attributes dealing with the relationship between the level of software performance and the amount of resources required. Maintainability is a set of attributes that describe what is necessary to maintain required software performance. Portability is a set of attributes dealing with the capability of software to be transferred from one environment to another. To continue this article please click here.

Dr. Seojeong Lee is an associate professor at Korea Maritime & Ocean University. She has published papers on software development issues related to navigation and communication systems, such as AIS and NAVTEX, including their applications on smart devices. She participates in the e-Navigation committees of the International Maritime Organization and International Association of Lighthouse Authorities.

Dr. Lee Alexander is a research affiliate professor at the Center for Coastal and Ocean Mapping at the University of New Hampshire. He serves on several international committees dealing with electronic charting, AIS and e-Navigation. He has published numerous papers and reports on navigation-related technologies, and is a co-author of a textbook on electronic charts.

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