Subject: [Trans] fyi: Bandwidth-efficient Transparency Logs via Append-only Authenticated Dictionaries (AAD)

From: =JeffH <[email-masked]>
Date: Fri, 22 Jun 2018 08:09:16 -0700

of possible topical interest. I could not find the paper, perhaps it is 
not published as yet...

From: security-seminar <[email-masked]>
Date: Thursday, June 21, 2018 at 9:16 PM
To: <[email-masked]>
Subject: Tuesday, June 26 -- Aline Tomescu: Bandwidth-efficient 
Transparency Logs via Append-only Authenticated Dictionaries

    Bandwidth-efficient Transparency Logs via Append-only
                  Authenticated Dictionaries

                         Alin Tomescu

                    Tuesday, June 26, 2018
                        Talk at 4:15pm
                          Gates 463A, Stanford, CA

Abstract:

Transparency logs enable anyone to audit a potentially malicious
service, paving the way towards a more ac- countable Internet. For
example, Certificate Transparency (CT) enables domain owners to
audit Certificate Authorities (CAs) and detect impersonation. Yet
to achieve their full potential, transparency logs must be easily
auditable by everyone. Specifically, everyone should be able to
verify both (non)membership of log entries and that the log remains
append-only. Unfortunately, current transparency logs either provide
small-sized (non)membership proofs or small-sized append-only proofs,
but never both. In this paper, we formalize and instantiate a new
primitive called an append-only authenticated dictionary (AAD) that
addresses this gap. Our construction provides succinct proofs for both
(non)membership and append-only checks, solving an open problem in
the authenticated data structures literature. We believe AADs can
help scale transparency logs and add more accountability to today?s
Internet.

Bio:

Alin is a PhD candidate at MIT focusing on public-key distribution
for HTTPS and secure messaging. His interests lie at the intersection
of theory and practice: he enjoys applied cryptography and building
systems.Recently, Alin worked on Catena, a system that leverages
the Bitcoin blockchain to prevent equivocation attacks on public-key
directories. In the past, Alin has worked on privacy-preserving file
systems, private social networking and secure email. Alin's other
interests include cryptocurrencies, anonymous networks and distributed
systems in general.