LH*s: a high-availability and high-security scalable distributed data structure

Abstract

LH*s is high availability variant of LH*, a Scalable Distributed Data Structure. An LH*s record is striped onto different server nodes. A parity segment allows one to reconstruct the record if a segment fails. The insert or key search time is about a msec on a 10 Mb/s net, and about 100 /spl mu/s at 1 Gb/s net, assuming the segments in the distributed RAM. The file size depends only on the distributed storage available, i.e., a RAM file can reach dozens of GB in practice. Data security is enhanced, as every site contains only partial and typically meaningless data. The price to pay is 20-50% more storage for the file than for an LH* file, and some additional messaging, especially for the scan search.