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:
Oct. 14, 2008
Filed:
Dec. 19, 2001
Eric Klingler, Monroe, WA (US);
Jeffrey Tedeschi, Woodinville, WA (US);
Eric Klingler, Monroe, WA (US);
Jeffrey Tedeschi, Woodinville, WA (US);
AT&T Mobility II LLC, Atlanta, GA (US);
Abstract
Disclosed embodiments include a method for synchronizing a cryptosystem. In one embodiment, the method uses existing control data that is transmitted as part of a connection establishment process in a wireless communication system. In one embodiment, messages that are normally sent between a base station and a remote unit during the setup of both originating and terminating calls are parsed to detect a particular control message that indicates the start of telephony data transmission. Detection of this message indicates a point at which encryption/decryption can begin, and is used to synchronize the cryptosystem. Synchronizing a cryptosystem involves generating an RC4 state space in a keyed-autokey ('KEK') encryption system. In one embodiment, Lower Medium Access Channel ('LMAC') messages are used according to a wireless communication protocol. This is convenient because the LMAC messages are passed through the same Associated Control Channel (“ACC”) processing that encrypts and decrypts the telephony data.