My previous post gave an overview of the graph visualisation techniques I've been using recently. Here's a more in-depth look at a program watermarked with the dynamic graph watermarking algorithm (as implemented in Sandmark). Is it stealthy? The short answer is 'no'. Here's why...
I've recently been working on visualising program slices using graphs.
Software watermarking by providing a means to identify the owner of a piece of software and/or the origin of the stolen software. The hidden watermark can be recognised or extracted, at a later date, by the use of a recogniser or extractor to prove ownership of stolen software. It is also possible to embed a unique customer identifier in each copy of the software distributed which allows the software company to identify the individual that pirated the software - this is known as fingerprinting. A software watermark should allow an author to prove ownership of a piece of copied software but how can the author demonstrate extraction of a watermark to a judge in a court of law?
There are two general types of software watermarking: static and dynamic. The latter stores the watermark in the execution or a data structure of a program. Execution path watermarking encodes the watermark in the sequence of branches taken during execution. A version of this algorithm has been implemented in Sandmark. How effective is execution path watermarking? Is it better than static watermarks, which are highly susceptible to semantics-preserving transformation attacks?
I recently completed the artist automaton model by cardboard model company cool4cats. This model is extremely clever in it's design - turn the handle and the artist actually draws. He doesn't draw exactly what he sees; he obviously has a dirty mind. The model kit is comprised of 20 A3 sheets of printed card. Each part is numbered, and marked with cut & fold lines and the model comes with a detailed step-by-step instruction booklet.
I attended the IEEE World Congress on Internet Security in London this week which is "an international forum dedicated to the advancement of the theory and practical implementation of security on the Internet and Computer Networks." The conference was held near Heathrow Airport, London. The conference was overall very interesting with some interesting people & good talks relating to my area of research, as well as other security topics. Disappointingly there was a low attendance and the conference could have been much better if more people had attended.
I completed my PTLLS micro-teach assessment yesterday; this involved teaching a 30-minute lesson with my peers as the students. I decided to choose a subject from my area of current teaching - the binary number system. I teach binary numbers to my 2nd years but had to make a few changes to the format to suit the PTLLS class.
Yesterday, I built a small Stirling engine from a cardboard kit. The kit included 4 cardboard pages of pre-punched parts, metal base plates & plastic side strips, a foam displacement piston, a few metal rods & plastic bearings and a latex glove. The kit is very well made and the instructions are fairly clear but there are few pictures.