XDA: A file package format for electronic documents

New document formats (such as OOXML, XPS, ePub, etc.) commonly use XML documents for descriptions and package in ZIP format, keeping data description being separated with display description. However, facing the developing document applications, the well-known ZIP format shows many deficiencies. Zip does not support incremental edit with revisions, random access while downloading, more efficient XML compression algorithms or fine-grained security policy, etc. A file package format named XDA is introduced. New features are detailed including data linearization for streaming download, incremental edit, and flexible efficient compression and encryption. Experiments show advantages of these features for document applications.