VMware, facing increased pressure from rivals Microsoft and Citrix Systems, will announce new products this week intended to let customers extend their use of virtualization beyond servers and into all corners of the data center, including storage and network equipment.

The new products, to be described at the company's VMworld conference in Las Vegas this week, are scheduled for release in 2009 and are an effort to build what VMware calls a "virtual data center operating system." VDC OS is not a product itself but a set of capabilities that will appear in updated releases of VMware's Infrastructure 3 software and other products.

"The VDC OS aggregates all hardware elements -- servers, storage and networking -- into a unified single resource. You take piece parts of the data center and let them act as a single big computer that can be allocated on demand to any application that needs the resources," said Bogomil Balkansky, VMware senior director of product marketing.

VMware thinks customers can use virtualization to transform their data centers into more flexible cloud-computing environments like those offered by Amazon and Google. Among the new software to be announced this week is vCloud, which will allow customers to export virtual environments -- including virtual machines and their attached policy information -- onto the servers of third-party cloud providers.

It's an ambitious plan that analysts say VMware needs to pursue to maintain a technology lead over rivals. VMware built an early lead in server virtualization but has been under pressure since Microsoft rolled out its own hypervisor earlier this year, and with Citrix expected to soon update its competing XenServer product.

Many questions are likely to go unanswered this week, including how the products will be priced and packaged and a timetable for delivery beyond simply "next year." Paul Maritz, VMware's new CEO, is due to unveil the new products and direction in a speech at VMworld Tuesday morning.

The new products can be broken roughly into two categories: software that works at the virtual machine level for improving application performance and availability and infrastructure products for managing the wider data center.

On the infrastructure side is vNetwork, which Balkansky said will allow customers to configure a single "virtual switch" for a pool of virtualized servers, instead of having to configure individual switches for each host computer. VMware will announce a product jointly developed with Cisco Systems to let network administrators configure the virtual switch from within Cisco's network management tools.