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:
Aug. 17, 2010
Filed:
Dec. 27, 2007
Tobias Martin, Rabenau, DE;
Ralf Schaffelhofer, Darmstadt, DE;
Joerg Schwenk, Henfenfeld, DE;
Deutsche Telekom AG, Bonn, DE;
Abstract
A method for establishing a common key for a group of at least three subscribers includes using a publicly known mathematical number group and a higher order element of the group g∈G. In the first step, a message corresponding to Ni: =gmod p is sent by each subscriber to all other subscribers (Tj), (zi) being a random number chosen from the set (1, . . . , p-2) by a random number generator. In the second step, each subscriber (Ti) selects a transmission key kij:=(g)for each other subscriber (Tj) from the received message (g), with i≠j, for transmitting their random number (zi) to the subscribers (Tj). In the third step, the common key k is calculated as k:=f(z, z, . . . , zn) for each subscriber Ti.