MARAD, the U.S. Maritime Administration released results of its study of electronic seal technologies, noting, "all RF based e-seals operate using the same basic underlying technology." However, "there are widely divergent solutions in terms of how the technology is applied. E-seals from different manufacturers use not only different communication frequencies but also widely different communication protocols, reader infrastructure architectures, and tamper detection methods." The six-month study was sponsored by MARAD and the U.S. Department of Transportation (DOT) as the Cargo Handling Cooperative Program (CHCP). CHCP included industry members from transportation companies, terminal operators, port authorities, analysts, and technology providers.
CHCP tested All Seal by All Set Tracking, DataSeal by Hi-G-Tek, eSeal by eLogicity, MacSema + Navalink by CGM, and SmartSeal by Savi.
In a joint press release, Savi, Hi-G-Tek, and E.J. Brooks expressed their disappointment that details validating the performance of lower-frequency tags contained in Annex B were not reflected in the report's Executive Summary. The lower-frequency seals demonstrated a significantly stronger signal and ability to propagate or transmit data around metal objects to fixed readers, according to Savi. Higher-frequency seals were limited to more line-of-sight transmission. For this reason, the three companies said they have concentrated on 433 MHz as the frequency of choice for their future products.
"The 433.92 MHz band has become the de facto standard for the U.S. Department of Defense, including for tracking assets in last year's Iraqi war, and it has also been successfully deployed in the global Smart and Secure Tradelanes initiative," said Fraser Jennings, vice president of standards and regulatory activities for Savi Technology. The government report pointed out, "If there is to be any sort of interoperability of devices used by the various carriers and shippers in the industry then it is critical to develop a set of standards that will allow communication between seals and readers from various manufacturers."
"Beyond simply specifying a frequency at which seals should operate, it will be absolutely necessary to establish standards for data, communication protocols, seal placement, and reader placement," the report continued. "These standards will have to allow seals from a variety of manufacturers to be reliably interrogated by readers systems from all other manufacturers at the facilities of all stakeholders. At the same time standards must be open enough to provide for a competitive marketplace and to allow for future innovation and evolution."
A copy of the report appears on the Maritime Administration's Web site: www.marad.dot.gov