Paper 2004/124
Universally Composable DKG with Linear Number of Exponentiations
Douglas Wikström
Abstract
Many problems have been solved by protocols using
discrete-logarithm based threshold cryptosystems. Such protocols
require a random joint public key for which the secret key is shared
among the parties.
A multiparty protocol that generates such a key is called a DKG
protocol. Until now no DKG protocol is known to be universally
composable.
We extend Feldman's original verifiable secret sharing scheme to
construct a DKG protocol, and prove that it is universally
composable. Our result holds in a common random string model under the
Decision Diffie-Hellman assumption. We stress that we do not need any
trapdoor for the common random string.
Our protocol is optimistic. If all parties behave honestly, each party
computes only
Note: Preliminary version.
Metadata
- Available format(s)
- PS
- Category
- Public-key cryptography
- Publication info
- Published elsewhere. Unknown where it was published
- Keywords
- threshold cryptography
- Contact author(s)
- dog @ nada kth se
- History
- 2004-05-26: received
- Short URL
- https://ia.cr/2004/124
- License
-
CC BY
BibTeX
@misc{cryptoeprint:2004/124, author = {Douglas Wikström}, title = {Universally Composable {DKG} with Linear Number of Exponentiations}, howpublished = {Cryptology {ePrint} Archive, Paper 2004/124}, year = {2004}, url = {https://eprint.iacr.org/2004/124} }