As recommended by Bob Jenkins, the original author of the ISAAC cryptographic random number generator algorithms, self-seeding ISAAC is a useful technique for increasing the cryptographic strength of the random numbers generated from a given ISAAC context; i.e., using random values generated by ISAAC to seed a new ISAAC context. This may not seem particularly valuable for one-off random values such as the session tokens generated in CL-ISAAC’s documented Quick Recipes, but when you need to generate millions of cryptographically-strong random numbers from a single context—such as for a One-Time Pad cipher—you notice the extra strength that self-seeding provides.
CL-ISAAC v1.0.4 is now available on GitHub, which includes the self-seeding context. It will be available in the April distribution of Quicklisp.
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