As the size of data storing arrays of disks grows, it becomes vital to protect data against double disk failures. A popular method of protection is via the Reed-Solomon (RS) code with two parity words. In the present paper we construct alternative examples of linear block codes protecting against two erasures. Our construction is based on an abstract notion of cone. Concrete cones are constructed via matrix representations of cyclic groups of prime order. In particular, this construction produces EVENODD code. Interesting conditions on the prime number arise in our analysis of these codes. At the end, we analyse an assembly implementation of the corresponding system on a general purpose processor and compare its write and recovery speed with the standard DP-RAID system.
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