Abstract: The present disclosure is directed towards a method of generating a modified permuterm index entry for use in a search for a keyword in a portion of an encrypted data collection, including identifying a keyword in one or more portions of an encrypted data collection; generating a permuterm index entry for the keyword, wherein the permuterm index entry comprises X values including a delimiting value inserted after the last value of the keyword, wherein the delimiting value marks the end of the keyword; generating a modified permuterm index entry for the keyword from the permuterm index entry, wherein the modified permuterm index entry comprises the first Y values of the permuterm index entry appended with a zero-or-more wildcard value, wherein Y is greater than zero and Y is less than or equal to X; and storing the modified permuterm index entry in a modified permuterm index.

Abstract: The present disclosure is directed towards a system, method, and computer readable storage medium for searchable encryption. A plurality of search terms are extracted from at least a part of a data structure. A keyed-hash value for each search term is calculated and stored in a list. The value of a bit in a predetermined position within each keyed-hash value is examined. If the value of the bit is a first value for ? of the keyed-hash values and a second value for ? of the keyed-hash values, wherein ? is a number greater or equal to two and the first value is different to the second value, then the set of keyed-hash values is split into two lists. Each list is assigned a search token value.

Abstract: The present disclosure is directed towards a system, method, and computer readable storage medium for searchable encryption. A plurality of search terms are extracted from at least a part of a data structure. A keyed-hash value for each search term is calculated and stored in a list. The value of a bit in a predetermined position within each keyed-hash value is examined. If the value of the bit is a first value for ? of the keyed-hash values and a second value for ? of the keyed-hash values, wherein ? is a number greater or equal to two and the first value is different to the second value, then the set of keyed-hash values is split into two lists. Each list is assigned a search token value.