System X Zero Downtime

1994 Successful lead engineer for development of System X (Public Telephone Exchange) projects

Background

System X was the public digital telephone exchange used throughout the UK. The major client was BT. I was employed as software engineer designing and developing software for the DSSS Central Software subsystem of the System X.

A specific enhancement required was for Zero Downtime. When a new release of software was installed, System X had to be brought offline during the update. This meant that the general public could not make telephone calls during this period.

Challenge

As a new member of the team, I had to prove my expertise as a software engineer learning new computer languages and understanding new platform architecture. I had to provide a solution to ensure that a software update could be performed without customers losing a service.

Actions

I liaised with other departments within GPT to provide a solution for the problem. I created a change request and subsystem design document describing the proposed solution. This involved a complete restructuring of existing code and a definition of new message sequencing to allow a system update to be performed without the system being brought offline. I presented my solution to various departments within the System X development teams.

Result

The project was successfully provided as part of a general System X release. No problems were reported when the release went live.

Meaning

This was the first of many projects that I was recognised a senior software engineer and team leader. I was subsequently a member of many working groups to design new functionality based on the System X architecture. I provided departmental presentations to introduce new projects, e.g. ISDN.