ACM-DRM 2010 Paper

A paper, co-written with Alexandre Karlov of Nagravision SA and titled “An efficient public-key attribute-based broadcast encryption scheme allowing arbitrary access policies“, has been accepted for presentation at the ACM-DRM 2010 workshop (list of accepted papers), which will be held in conjunction with the 17th ACM-CCS in Chicago (USA) on October 4th, 2010. The final version of our paper is not ready yet, but here is at least its abstract:

We describe a new public-key and provably secure attribute-based broadcast encryption scheme which supports complex access policies with AND, OR and NOT gates. Our scheme, especially targeting the implementation of efficient Pay-TV systems, can handle conjunctions of disjunctions (CNF) by construction and disjunctions of conjunctions (DNF) by concatenation, which are the most general forms of Boolean expressions. It is based on a modification of the Boneh-Gentry-Waters broadcast encryption scheme in order to achieve attribute collusion resistance and to support complex Boolean access policies. The security of our scheme is proven in the generic model of groups with pairings. Finally, we compare our scheme to several other Attribute-based Broadcast Encryption designs, both in terms of bandwidth requirements and implementation costs.

On the funny side, the DRM field looks like to adopt more and more zero-knowledge techniques: the first e-mail received from the program committee is a good illustration thereof (the ambiguity has then been corrected very quickly by the PC chairs):

Dear Pascal Junod:

Thank you very much for submitting your paper "An efficient public-key attribute-based broadcast encryption scheme allowing arbitrary access policies" to ACM-DRM 2010. We are very pleased to inform you that your submission was not among the selected ones.

Please revise your paper according to the reviewers's comments (see below). You should prepare your camera-ready version according to the ACM proceedings format ( You will be contacted by Lisa Tolles (Sheridan Printing) with detailed instructions and guidelines. The deadline for submitting your revised version is August 16 (this is a firm deadline).

Yours sincerely,

Hongxia Jin, Marc Joye ACM-DRM 2010 Program Chairs


Remember about the following recurrent scenario: you are writing some paper using \LaTeX with one or several colleagues, you edit the paper on your side and you would like to send the updated version to the others, emphasizing the changes you made in such a manner that your colleagues can quickly figure out what was updated. You can rely on the *nix common tool diff, or on the diff-ing capabilities of your preferred text editor. This is what I did until recently.

A colleague of mines had the excellent idea to show me the latexdiff tool, which is freely available on CTAN. Here is a small sample of its capabilites: let’s assume that I received the following LaTeX document (text shamelessly stolen from Wikipedia), rendering to

After several corrections, the final version should sound something like

Using the simple command

latexdiff uncorrected.tex corrected.tex > diff.tex

we get the following:

latexdiff will definitively be part of my toolbox from now on!