“A program obfuscator would be a powerful tool for finding plausible constructions for just about any cryptographic task you could conceive of,” said Yuval Ishai, of the Technion in Haifa, Israel.
Precisely because of obfuscation’s power, many computer scientists, including Sahai and his colleagues, thought it was impossible. “We were convinced it was too powerful to exist,” he said. Their earliest research findings seemed to confirm this, showing that the most natural form of obfuscation is indeed impossible to achieve for all programs.
Then, on July 20, 2013, Sahai and five co-authors posted a paper on the Cryptology ePrint Archive demonstrating a candidate protocol for a kind of obfuscation known as “indistinguishability obfuscation.” Two days later, Sahai and one of his co-authors, Brent Waters, of the University of Texas, Austin, posted a second paper that suggested, together with the first paper, that this somewhat arcane form of obfuscation may possess much of the power cryptographers have dreamed of.
“This is the first serious positive result” when it comes to trying to find a universal obfuscator, said Boaz Barak, of Microsoft Research in Cambridge, Mass. “The cryptography community is very excited.” In the six months since the original paper was posted, more papers have appeared on the ePrint archive with “obfuscation” in the title than in the previous 17 years.
Gary Edwards on 09 Sep 10A while back I included the following as one of the areas of interest of the PDF/D Consortium: Structured Documents and Single Sourcing: improving round-trips to document softwareWhat did I mean by Structured Documents? For years Solid Documents has been converting PDF files to Word documents with a focus on retaining format and layout to allow customers to repurpose the content. While this is a great solution for a large amount of customers, it is not the only type of reconstruction that is interesting. PDF is by nature a "document" format: the layout is in the form of pages. Content also needs to exist in alternate formats like a continuously flowing stream. Use cases for continuously flowing content include:conversion to HTML to reflow for form factors other than "pages"conversion to content management systems where structure is more important than layout and formattingconversion for alternate readers for people with disabilities (text to speech, etc)Reconstruction for these use cases focuses more on the structure of the document than on the layout and formatting. For example, we need to take unstructured PDF files and recognize columns, tables, lists, headers and footers, etc. This allows us to organize the content in a logical structure. Ultimately, we'll recognize topics and sections too so that we can produce logical hierarchies from plain old non-tagged PDF files. One great example of where conventional PDF pages are not the most appropriate way to read a document are on small screens of handheld devices. For example, the typical Blackberry has a 3"x2" screen with a resolution something like 320x240 pixels.
