to solve heterogeneity issues in electronic document exchanges.

The Portable Document Format was developed by Adobe Systems Inc. Even though it is supported by nearly every application on any machine, plain text ASCII has failed to become popular because it does not allow text formatting, image embedding and other features that are key to an efficient communication. The diversity of platforms, formats and applications has called for a common technology to overcome those differences and produce universally readable documents to be exchanged without limitations. The number of files that are published and exchanged through the Internet is constantly growing and electronic document exchange is becoming more and more popular among Internet users. One of them is relevant to the scientific community and it pertains to the ability to overcome the blind review process of a paper, revealing information related to the anonymous referee (e.g., the IP address of the referee). There are several applications of such an issue. From a PDF document, it is possible to retrieve any text or object previously deleted or modified, extract user information and perform some actions that may be used to violate user privacy. This paper investigates the Portable Document Format and shows that it is not immune from some privacy related issues that affect other popular document formats. PDF documents are also credited with being more secure than other document formats such as Microsoft Compound Document File Format or Rich Text Format. It allows reliable reproductions of published materials on any platform and it is used by many governmental and educational institutions, as well as companies and individuals. The Portable Document Format (PDF) was developed by Adobe in the early nineties and today it is the de-facto standard for electronic document exchange.

Adobe Acrobat 9 Pro Extended Portable