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:
Nov. 02, 2004
Filed:
Feb. 12, 1999
Markus Hakaste, Helsinki, FI;
Nokia Mobile Phones Limited, Espoo, FI;
Abstract
The invention relates to a method and arrangement for ciphering an information transfer connection. The invention can be advantageously applied in a TDMA (Time Division Multiple Access) cellular system offering broadband circuit switched services. An essential idea of the invention is that the information to be ciphered in a transmission burst is divided into at least two blocks ( ) and said blocks are ciphered in ways that are not identical with each other ( to ). Then the reliability of ciphering is better because the amount of information encoded using one and the same ciphering algorithm and key is smaller. In addition, the reliability of the ciphering can be varied by changing the number and/or size of the information blocks in a burst.