If your shared key is significantly larger then the plain text and the key is sufficiently random than using the key as a rotating shared key is non trivial or nearly impossible to break.

http://en.wikipedia.org/wiki/One_time_pad is a similar choice which you may want to look at, the advantage for these is that they require little processing power to compute.

In reply to Re^2: Encryption using perl core functions only by neosamuri
in thread Encryption using perl core functions only by redhotpenguin

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