Whether an MOF file was pushed (using Start-DSCConfiguration) or pulled (using a DSC pull server), the next step is the actual execution of the MOF file. If pushed, the execution happens interactively or in a PowerShell job depending on how you called the cmdlet. If pulled, the Local Configuration Manager (LCM) schedules and executes the MOF file without user input or oversight.
LCM is part of the DSC system installed on the target node and is responsible for receiving, coordinating, and executing configurations on target nodes. LCM itself is configurable using DSC and is flexible enough to allow multiple types of deployments.
The phases described earlier will be covered in much more detail in the upcoming chapters, so do not worry if some of it does not make sense.