公开(公告)号：GB2508599A

公开(公告)日：2014-06-11

申请号：GB201221757

申请日：2012-12-04

Applicant: IBM

Inventor： VISEGRADY TAMAS ,  WERNER KLAUS ,  JORDAN MICHAEL J ,  HOCKER MIKE D

IPC: G06F9/445

Abstract: A system for downgrading (migrating from a later version to an earlier version) a software module [fig. 1; 18] is disclosed, where the software module comprises an application or firmware [fig. 1, 14] and a compatibility database [fig. 1; 16] specifying dependencies and compatibilities between different versions, revisions or editions of the software module. Downgrading the module comprises retrieving status information from the software module (such as metadata indicating the version), identifying a compatible intermediate version 68 between the current version 64 and target version 60, implementing 66 the intermediate version, and completing the download. The intermediate version may be a later edition of firmware (v2) and an earlier edition/format of persistent data or database (v1) (the later firmware edition being able to process both the later and earlier formats of data). Subsequently, the data is downgraded to a compatible format 58 before the firmware is downgraded. The persistent data might comprise the compatibility database.