Microsoft's New Binary File Formats: The EOOXMl XML Binary InfoSet

PlexNex: Analyzing the Microsoft Office Open XML License

• Whoa! Check out the Marbux commentary. This has already happened. In his blog titled, "The Formats of Excel 2007",
  
  XML expert Rob Weir demonstrates for us that MSOffice 2007 Excel has a new file format. Rob demonstrates that there are four file format choices in Excel; EOOXML, Legacy XLS binary, and two new binary extensions of EOOXML: "Excel Macro-Enabled Workbook" - xlsxm, and "Excel Binary Workbook" - xlsb.
  
  The new binaries are proprietary extensions to EOOXML. xlsb in particular looks to be something known as a XML Binary InfoSet.. XBiS is a compressed form of an XML file used in situations where bandwidth and device cpu constraints demand such an extreme. We can't be sure about xlsb, but it looks like a duck, walks like a duck, quacks like a duck and therefore....
  
  This must be some kind of record. EOOXML isn't yet 30 days old and Micrsoft has eXtended it with a proprietary binary representation not available to the rest of the world. And XBiS was designed so that implementations would be open and application and platform independent. But that's not what we see with Microsoft's xlsb.
  
  What Marbux is pointing out here is that only Microsoft has the legal rights to do this proprietary eXtension of EOOXML. Beat the drums. Sound the alarms. Hide the women and children. Nothing has changed. The longboats are fancier, there are more of them. The swords of the pillagers remain just as sharp. Their determination and drive just as strong.
  
  Some quick background references:
  

  Compression, XML, Binary Infoset - O'Reilly Digital Media Blog