On the deception probability of authentication codes

The optimal strategy of deception to be followed by an opponent is described. Using this strategy an algorithm is developed to calculate the probability of P/sub D/ of deception for a given encoding function. On the basis of projective planes we construct some authentication codes to minimize P/sub D/. These codes have P/sub D/ smaller than the bound P/sub D/ /spl ges/ K/sup -1/2/ given here.<
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