While useful, revocation checking can leak potentially sensitive information. In particular, third parties of dubious trustworthiness discover two things: (1) the identity of the party posing the query, as well as (2) the target of the query. The former can be easily remedied with techniques such as onion routing or anonymous web browsing. Whereas, hiding the target of the query is not as obvious. Arguably, a more important loss of privacy results from the third party’s ability to tie the source of the revocation check with the query’s target. (Since, most likely, the two are about to communicate.) This paper is concerned with the problem of privacy in revocation checking and its contribution is two-fold: it identifies and explores the loss of privacy inherent in current revocation checking, and, it constructs a simple, efficient and flexible privacy-preserving component for one well-known revocation method.
Category / Keywords: cryptographic protocols / privacy-preserving protocols, revocation, implementation Date: received 20 Feb 2006, last revised 20 Jun 2006 Contact author: gts at ics uci edu Available format(s): Postscript (PS) | Compressed Postscript (PS.GZ) | PDF | BibTeX Citation Version: 20060621:003118 (All versions of this report) Short URL: ia.cr/2006/066 Discussion forum: Show discussion | Start new discussion