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Technical Report

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Technical Report Number



We construct a bump-in-the-wire (BITW) solution that retrofits security into time-critical communications over bandwidth-limited serial links between devices in legacy Supervisory Control And Data Acquisition (SCADA) systems, on which the proper operations of critical infrastructures such as the electric power grid rely. Previous BITW solutions do not provide the necessary security within timing constraints; the previous solution that does is not BITW. At a hardware cost comparable to existing solutions, our BITW solution provides sufficient security, and yet incurs minimal end-to-end communication latency.


This technical report is the extended version of the paper to appear in IFIP SEC 2008 under the same title. An earlier version of the paper appeared as Dartmouth Computer Science Technical Report TR2007-603.