Data is secured in a computer network to transparently establish and
manage a separation of user-based communities of interest based upon
crypto-graphically separated, need to know, security levels. Data from a
source document, data object or data stream is filtered to form subsets
of extracted data and remainder data based upon security levels for the
communities. Extracts are stored in assigned memories. Full or partial
plaintext reconstruction is permitted only in the presence of assigned
security clearance for the community of the inquiring party. Encryption,
corresponding to security levels, establishes separation of secured data.
The information processing system uses a data filter to extract security
sensitive words, data objects, etc., a distributed storage system and a
compiler is used to reconstruct plaintext based on security clearance.
Multiple level encryption in one document is also available.