Microsoft Dynamics AX 2009 introduces a new batch framework that supports server-based batches without the need for a client. All new batch jobs in Microsoft Dynamics AX 2009 use the new batch framework. Most existing batch jobs from previous releases are being migrated to the new framework. Client-side batches are supported in Microsoft Dynamics AX 2009 but are not recommended.
From AX 2009, we don’t need to run a client to run scheduled jobs, if you specify that the batch job runs on server. The batch job runs on server by default unless the developer overrides the runImpersonated method and make it return false.
The old client-based batch processing is still in AX 2009 for backward compatibility and will be removed in future versions. The old client-based batch system, that was based on a dedicated client, cannot be replaced in some situations. For example, due to some technical problems that the compiler cannot be run on the server tier, which means the task to run a scheduled compilation or cross-reference update must be run on client-tier.