In this paper we investigate the security of the server aided
RSA protocols RSA-S1 and RSA-S1M proposed by Matsumoto, Kato and Imai
resp. Matsumoto, Imai, Laih and Yen. We prove lower bounds for the
complexity of attacks on these protocols and show that the bounds are
sharp by describing attacks ... more >>>

Many Boolean functions have short representations by OBDDs (ordered
binary decision diagrams) if appropriate variable orderings are used.
For tree-like circuits, which may contain EXOR-gates, it is proved
that some depth first traversal leads to an optimal variable ordering.
Moreover, an optimal variable ordering and the resulting OBDD
can ... more >>>