The world of enterprise IT is changing - from server to desktop and everywhere in between.

You've heard the buzzwords: service architectures, loosely coupled applications, virtualisation, serialisation, network storage, network processing. These are just some of the ways in which the way we do IT are changing - a change that will have as much effect on the way businesses work as the arrival of the desktop PC.

I'm Simon Bisson, a technology journalist and consultant who's been writing about these issues for a long time now - and with the real world experience of designing and building large-scale loosely coupled systems: from telecom research labs to the early days of national ISPs, and from photo hosting platforms to telecom service platforms. It's been a long road from the early '90s to today - and a lot is happening around the world.

A lot of what I've been writing recently in my pieces for The Guardian and elsewhere has been about what I'm calling a "phase change in Enterprise IT". It's that point where all these changes are coming together to change the way we design and deliver IT. It's a place where hardware is abstract, where the OS and storage are virtual, where UI becomes contextual, and where process and service mean much more than applications.

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