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:
Mar. 25, 2008
Filed:
Mar. 10, 2005
Glen Kramer, Petaluma, CA (US);
Lawrence D. Davis, Petaluma, CA (US);
Edward W. Boyd, Petaluma, CA (US);
Ryan E. Hirth, Windsor, CA (US);
Ngo Thahn Ho, Arlington, TX (US);
Glen Kramer, Petaluma, CA (US);
Lawrence D. Davis, Petaluma, CA (US);
Edward W. Boyd, Petaluma, CA (US);
Ryan E. Hirth, Windsor, CA (US);
Ngo Thahn Ho, Arlington, TX (US);
Teknovus, Inc., Petaluma, CA (US);
Abstract
One embodiment of the present invention provides a system that decrypts downstream data in an Ethernet passive optical network (EPON). During operation, the system receives a data frame which is encrypted based on a remote input block and a session key, wherein the remote input block is constructed based on a remote cipher counter and a remote block counter. The system adjusts a local cipher counter based on a received checksum located in a preamble of the data frame, wherein the local cipher counter is substantially synchronized with the remote cipher counter. In addition, the system truncates the local cipher counter by discarding n least significant bits thereof. The system then constructs a local input block based on the truncated cipher counter and a local block counter for the received data frame. Next, the system decrypts the data frame based on the local input block and the session key.