Patent · US Expired

Multiprocessor system with interactive synchronization of local clocks

US7340630B2 · kind B2 · utility

14Cited by
11References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 8, 2003
Grant dateMar 4, 2008
Priority date
Expiry dateOct 9, 2024

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04J3/0638
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

A multiprocessor computer system comprises multiple data processors, each with an internal clock for providing time stamps to application software. The processors take turns as synchronization masters. The present master transmits a “request” time stamp (indicating the time of transmission according to the local clock) to the other (“slave”) processors. Each slave processor responds by returning a “response” time stamp (indicating the time of transmission of the response according to the local slave clock) of its own along with the received request time stamp. The master calculates clock adjustment values from the time of receipt of the responses and the included time stamps. This allows asynchronous clocks to be synchronized so that application time stamps can be validly compared across processors.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.