To design our protocol, we first present a new, optimally resilient statistical asynchronous verifiable secret sharing (AVSS) protocol with n = 3t+1, which significantly improves the communication complexity of the only known optimally resilient statistical AVSS protocol of Canetti et al. Our AVSS protocol shares multiple secrets simultaneously and incurs lower communication complexity than executing multiple instances of an AVSS protocol sharing a single secret. To design our AVSS protocol, we further present a new asynchronous primitive called asynchronous weak commitment (AWC), which acts as a substitute for asynchronous weak secret sharing (AWSS), which was used as a primitive for designing AVSS by Canetti et al. We observe that AWC has weaker requirements than the AWSS and hence can be designed more efficiently.
The common coin primitive is one of the most important building blocks for the construction of an ABA protocol. The best known common coin protocol of Feldman et al. requires multiple instances of an AVSS protocol sharing a single secret as a black-box. Unfortunately, this common coin protocol does not achieve its goal when the multiple invocations of AVSS sharing a single secret is replaced by a single invocation of an AVSS protocol sharing multiple secrets simultaneously. Therefore in this paper, we extend the existing common coin protocol to make it compatible with our new AVSS protocol (sharing multiple secrets). As a byproduct, our new common coin protocol is much more communication efficient than the existing common coin protocol.Category / Keywords: cryptographic protocols / Publication Info: Few of the results in the paper appeared in PODC 2012 and PODC 2009 Date: received 17 Jan 2011, last revised 11 Jul 2012 Contact author: partho_31 at yahoo co in, partho31@gmail com, arpitapatra10@gmail com, arpita@cs au dk Available format(s): PDF | BibTeX Citation Version: 20120711:102934 (All versions of this report) Short URL: ia.cr/2011/031 Discussion forum: Show discussion | Start new discussion