Expand Networks has developed a VMware-packaged virtual version of its Compass WAN accelerator appliance.

The company reckons that virtualisation will be key to getting WAN acceleration into many of the enterprises that haven't yet picked it up. In particular, Expand said it will help it target the growing market for server-based computing and VDI, or virtual desktop infrastructures, as well as offering a cheaper solution for branch offices.

The virtual WAN optimisation controller, or VWAN, also ties into the virtual datacentre concept - which is seeing companies use virtual machines to increase server utilisation, cut energy and software licensing costs, and simplify system management - said Expand CTO Efi Gatmor.

"Our modular and open architecture enables us to provide a full virtual solution that doesn't rely on specific hardware," he claimed. "In line with this trend, our VWAN optimisation roadmap supports the enterprises' strategy for moving to a pure virtual datacentre infrastructure.

"Initially, our VWAN optimisation deployment will be done on VMware ESX and VMware Server. In the future, other virtualisation platforms will be supported."

Expand is the latest of several companies who have seen virtualised appliances as a significant opportunity.

Gatmor acknowledged that there are performance overheads involved in running WAN acceleration in a virtual machine, especially in the area of I/O, but said these can be overcome by using shared or networked storage.

The VWAN package is planned to be available in the third quarter, he said, adding that it would give Expand "flexibility in pricing."

Expand did a deal last year with 3Com to run its WAN accelerator software, which is Linux-based, on the latter's MSR routers.