Nicolas Prigent describes Powershell Desired State Configuration:
The management and maintenance of servers quickly becomes complex without standardisation. PowerShell allows us many ways of responding to different problems and occasionally bypassing certain restrictive techniques. The danger is that we end up with a plethora of scripts in order to manage a server, all more complicated than the other, and this works. We do much better with a standard way of automating a task
DSC gives us a declarative model for system configuration management. What that really means is that we can specify how we want a workstation or server (a ‘node’) to be configured and we leave it to PowerShell and the Windows Workflow engine to make it happen on those target ‘nodes’. We don’t have to specify how we want it to happen.
DSC is great for keeping servers and server configurations in sync.