Fast Infoset

What Does Fast Infoset Mean?

Fast Infoset (FI) is an international standard that details a binary-encoding information format as an Extensible Markup Language (XML) alternative. FI is engineered to support optimized serialization more efficiently than XML, which is based on text.


FI is officially known as International Telecommunications Standard Sector (ITU-T) Rec. X.891 and International Standard for Organization/International Electrotechnical Commission (ISO/IEC) 24824-1.

Techopedia Explains Fast Infoset

According to the FI standard, a data model is specified with the following components:

  • Document information
  • Document format/type declaration items
  • Character-related information
  • Notation-related information
  • Namespace-related information
  • Element-related information
  • Attribute information items
  • Processing instruction information
  • Unexpanded entity reference information
  • Comment information
  • Unparsed entity information

FI may be viewed as an XML gzip, even in cases where FI optimizes document size and computer resource usage. Like gzip, no information is lost during XML/FI conversion.


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