Microsoft delivered a beta of its Windows Azure Online Backup service back in March 2012. Late last week, officials shared more on the updated version of that service, which the company is calling a "preview."

Windows Azure Online Backup is a cloud-based backup service that allows server data to be backed up and recovered from the cloud. Microsoft is pitching it as an alternative to on-premises backup solutions. It offers block-level incremental back ups (only changed blocks of information are backed up to reduce storage and bandwidth utilization); data compression, encryption and throttling; and verification of data integrity in the cloud, among other features.

The beta of the Azure Online Backup service only worked with Windows Server 2012 (then known as Windows Server 8). The newly released Azure backup preview also works with the near-final release candidate build of Windows Server Essentials 2012 , which is Microsoft's new small business server. The final version of Windows Server Essentials 2012 is due out before the end of this year.

The Azure backup service also supports the Data Protection Manager (DPM) component of the System Center 2012 Service Pack 1. Microsoft made available the beta of System Center 2012 Service Pack 1 on September 10, and has said the final version of that service pack will be out in early 2013.

Alongside the new preview of the backup service, Microsoft also released an updated preview build of the Windows Azure Active Directory Management Portal. This portal is the vehicle for signing up for the Windows Azure Online Backup service and how administrators can manage users' access to the service.

Microsoft officials said they had no comment on when Microsoft plans to move Windows Azure Online Backup from preview to final release.

Speaking of System Center 2012 Service Pack 1, there are a number of new capabilities and updates coming in this release. SP1 enables all System Center components to run on and manage Windows Server 2012. SP1 adds support for Windows Azure virtual machine management and is key to Microsoft's "software defined networking" support. On the client-management side, SP1 provides the ability to deploy and manage Windows 8 and Windows Azure-based distribution points.

The Configuration Manager Service Pack 1 component -- coupled with the version of Windows Intune due out in early 2013 -- will support the management of Windows RT and Windows Phone 8 devices .