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:
Feb. 08, 2011
Filed:
Jul. 27, 2006
Daniel Christian Biederman, San Jose, CA (US);
Haichuan Tan, Santa Clara, CA (US);
Senthil Arumugam, San Jose, CA (US);
Howard Borchew, Saratoga, CA (US);
Daniel Christian Biederman, San Jose, CA (US);
Haichuan Tan, Santa Clara, CA (US);
Senthil Arumugam, San Jose, CA (US);
Howard Borchew, Saratoga, CA (US);
Cisco Technology, Inc., San Jose, CA (US);
Abstract
Disclosed are, inter alia, methods, apparatus, data structures, computer-readable media, mechanisms, and means for maintaining consistency among timestamp counters distributed among multiple devices. When timestamp counters are distributed among multiple physical devices, variances in their timestamp values can occur, such as, but not limited to those cause by variances among clocks in these different devices, different routing delays, different components, etc. These differences may be same, but still not allow high enough precision, especially as packet and processing rates continue to increase (which also causes clocking rates of devices to increase). One implementation distributes a time advance signal to each of these devices, which each device independently uses to determine when to advance its timestamp counter in response to its clock signal. These timestamps may be generated according to IEEE 1588 Standard for a Precision Clock Synchronization Protocol for Networked Measurement and Control Systems; and/or Physical Layer Transceivers (PHYs) may be disposed in each of the different physical devices.