We introduce the concept of forward-secure signatures with untrusted update, where the key update can be performed on an encrypted version of the key. Forward secure signatures with untrusted update allow us to add forward security to signatures, while still keeping passwords as a second factor of security. We provide a construction that has performance characteristics comparable with the best existing forward-secure signatures. In addition, we describe how to modify the Bellare-Miner forward secure signature scheme to achieve untrusted update.
Category / Keywords: public-key cryptography / Publication Info: An extended abstract is to appear in ACM CCS 2006. Date: received 30 Aug 2006 Contact author: xb at boyen org Available format(s): PDF | BibTeX Citation Version: 20060831:090528 (All versions of this report) Short URL: ia.cr/2006/297 Discussion forum: Show discussion | Start new discussion