Suresh D Mahanty

US Patent:

60700122, May 30, 2000

Filed:

May 22, 1998

Appl. No.:

9/083020

Inventors:

William H. Eitner - Milpitas CA
Suresh D. Mahanty - Mountain View CA

Assignee:

Nortel Networks Corporation

International Classification:

G06F 9445
G06F 900
G06F 15177

US Classification:

395712

Abstract:

A method and system for updating a software subsystem while services are being provided by the software subsystem is provided. Initially, instructions are processed from a primary software subsystem loaded at a first base address associated with a primary storage unit. A secondary software subsystem is downloaded at a second base address associated with a secondary storage unit while the primary software subsystem is being executed. The secondary software subsystem typically contains an updated version of the primary software subsystem. To install the updated software subsystem, the first base address associated with the primary storage unit is swapped with the second base address associated with the secondary storage unit. Execution continues using the updated software subsystem without a significant interruption in service.