Compression and shipboard internet access

As long as real and flat-rate broadband satellite internet is not ubiquitous at sea, there will be a need to handle data traffic as efficient as possible. A detailed article in Digital Ship’s February newsletter (pdf, p.8-13) looks at the various compression methods that are being used in order to optimize the throughput for satellite internet. There are different ways of doing it, and systems deployed by KVH, Inmarsat, Iridium, Seawave, Accelerator from Expand Networks and Globalstar are being reviewed and explained.
“Much attention is given to the compression of data, processing documents and image files so they use the minimum data possible, to reduce the ship shore communications cost. The choice is not whether to compress, but how well and how easily it can be achieved.”
“While compression itself is important, preventing unwanted transmissions, repeat transmissions and making full use of available resources is perhaps even more important. Prevention coupled with superior compression remains the best approach to reducing costs.”
It furthermore discusses the future of shipboard internet access as well, ‘warning’ Inmarsat that it will have to match its offering to that of the VSAT service providers. And, if that happens, we might be surprised about the market uptake of these services. Another development putting pressure on Inmarstat is of course the Boeing announcement that they will introduce their Connexion service to the maritime market.
“According to Worldlink, internet access onboard vessels will not happen with MPDS, but will only happen when VSAT like tariffs are available from Inmarsat. “If you consider downloading the CNN front page is 200-300 kilobytes that’s about $12.0 at current going rates for MPDS,” comments Asad Salameh, CEO of World-Link. “No compression or caching is going to reduce this number enough so that a crew member can relax on the internet.”