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Linux users may have been pleased to find that Adobe has finally made available a new version of its Acrobat Reader, with accessibility features, a much slicker interface than Acrobat 5.x and new and other spiffy features. However, there are a few other features that Linux users should be aware of. A company called Remote Approach is promising to alert PDF publishers as to the "reach and use of their materials." We were curious to find out how Remote Approach was going to make good on its promise, given that PDF has largely been seen as a one-way medium. To find out, we created a test account and uploaded a PDF to be "tagged" by Remote Approach, and then downloaded the modified document to see whether Remote Approach could log our use of the document.
Remote Approach's reporting did not work when we viewed the document with Kpdf, Xpdf and Adobe Reader 5.0.10. It also failed using Apple's "Preview" application on Mac OS X. The document was still viewable with no apparent glitch in other PDF readers, but the reporting function did not work. However, when we opened the file using Adobe Acrobat Reader 7, Remote Approach started logging views from our IP address. After doing a little research, we found that Adobe's Reader was connecting toeach time we opened the document. The information is submitted over port 80 using HTTP, so it is unlikely that a home or office firewall would, in a normal configuration, block the activity, unless the firewall administrator is attempting to block Web browsing.