The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 24, 1997
Filed:
Sep. 15, 1995
James P Gray, Chapel Hill, NC (US);
Stephen M Matyas, Poughkeepsie, NY (US);
Mohammad Peyravian, Cary, NC (US);
Gene Tsudik, Thalwil, CH;
International Business Machines Corporation, Armonk, NY (US);
Abstract
The security provided by encryption of ATM cells is enhanced by testing each cell for low data content level. If a cell has a low data content, its contents are nevertheless compressed and the resulting string is used to replace the original data. A length character and a randomly generated number which are added to the freed-up byte positions in the data field of the cell. The entire, modified data field is encrypted before the cell is transmitted. At a receiving system, a compression indicator is checked to determine whether the cell contains original or compressed data. If necessary, the length field and the random number are stripped and the remaining cell data is decompressed before the cell data is decrypted.