• Publications
  • Influence
How to share a secret with cheaters
  • M. Tompa, H. Woll
  • Mathematics, Computer Science
    Journal of Cryptology
  • 1 August 1988
TLDR
This paper demonstrates that Shamir's scheme is not secure against certain forms of cheating, and a small modification to his scheme retains the security and efficiency of the original and preserves the property that its security does not depend on any unproven assumptions such as the intractability of computing number-theoretic functions.
Algorithms for the Certified Write-All Problem
TLDR
New upper bounds on the complexity of the certified write-all problem with respect to an adaptive adversary are proved and it is shown that for any $\epsilon > 0$, there exists an $O(p^{1+\ep silon})$ work algorithm for the p-processor $p-memory cell write- all.
Optimal time randomized consensus—making resilient algorithms fast in practice
TLDR
This paper presents an optimally fast and highly resilient shared-memory randomized consensus algorithm that runs in only O(log n) expected time if @or less failures occur, and takes at most O(*) expected tim~ for any j.
Random self-reducibility and zero knowledge interactive proofs of possession of information
  • M. Tompa, H. Woll
  • Computer Science
    28th Annual Symposium on Foundations of Computer…
  • 12 October 1987
TLDR
It is shown that any "random self-reducible" problem has a zero knowledge interactive proof of this sort, and new zeroknowledge interactive proofs are exhibited for "knowledge" of the factorization of an integer, nonmembership in cyclic subgroups of Zp*, and determining whether an element generates Zp*.
Wait-free parallel algorithms for the union-find problem
TLDR
This paper gives a wait-free implementation of an efficient algorithm for union-find and shows that the worst case performance of the algorithm can be improved by simulating a synchronized algorithm, or bysimulating a larger machine if the data structure requests support sufficient parallelism.
How to Share a Secret with Cheaters
TLDR
It is demonstrated that Shamir's scheme is not secure against cheating, and a small modification to his scheme retains the security and efficiency of the original, and preserves the property that its security does not depend on any unproven assumptions such as the intractability of computing number-theoretic functions.
Reductions among Number Theoretic Problems
  • H. Woll
  • Computer Science, Mathematics
    Inf. Comput.
  • 1 March 1987
TLDR
An overview of reductions among the problems of integer factorization and the discrete logarithm problem gives an overview of new reductions from squarefreeness to Euler's function φ ( n ), and a probabilistic polynomial time reduction from order modulo a prime power.