Patent · US Expired

Maintaining consistency of database replicas

US6098078A · kind A · utility

245Cited by
8References
32Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 23, 1996
Grant dateAug 1, 2000
Priority date
Expiry dateDec 23, 2016

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S707/99954
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A method and apparatus for maintaining consistency in databases among data processors of a computer network involves an improved epidemic protocol involving the generation of database version vectors for database replicas. Overhead of the protocol grows linearly with the number of data items being copied during an update propagation, not with the number of data items as in typical epidemic protocols. Since this number is less than the total number of data items in the database, the present protocol promises significant reduction in overhead. A log record is generated including at least the name of the updated data item. The log record has an associated time stamp for the updated data item name in one embodiment or an associated version vector value in another. In the event of out-of-bound copying, an auxiliary log record is maintained.

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