Longer Cascades? Sample Clauses

Longer Cascades?. ≥ ≥ Xxxxx and Xxxxxx [16] suggested the cascade of ρ 1 evaluations of LRW2, and proved that for even ρ this construction is secure up to approximately 2ρn/(ρ+2) queries. Xxx et al. [18] proved that if the universal hash functions are replaced by random functions, security up to 2ρn/(ρ+1) is achieved. It is generally conjectured that the security of the cascade of ρ LRW2’s is 2ρn/(ρ+1) [16–18], but also for this larger cascade, nothing is known on the attack side, besides the trivial attack in 2n queries. Unfortunately, it does not seem possible to generalize the attack of Sect. 3 nor the security proof of Sect. 5 to larger cascades. As before, it is noteworthy that a cascade of ρ 1 evaluations of TEM can be attacked in approximately 2ρn/(ρ+1) queries [2].