Virtualization has moved beyond applications themselves to software that makes those applications run faster over a network.

WAN (wide-area network) acceleration vendor Certeon has introduced aCelera, an application-acceleration platform that comes without hardware and is designed to run on servers virtualised with VMware and with Microsoft's upcoming Hyper-V technology.

Like other application accelerators, aCelera shortens response times for applications that have to run over networks, namely between central and branch offices. But aCelera does it without a dedicated appliance. The software is designed to run on standard x86 hardware in one or more virtual machines, so it can share resources with an enterprise's overall computing infrastructure.

This allows for scaling up application acceleration as needed and also avoidedrequiring users to buy a specialised device for each end of a WAN connection, vice-president of marketing at Certeon, sa Gareth Taube, said.

Many large enterprises are looking to server and storage virtualisation to become more efficient and keep more IT gear at central sites. Centralisation helps drive the need for WAN acceleration as branch-office employees rely on far-away data centers to run their applications. Certeon, a venture-capital-backed startup in Massachusetts, is turning that technology to its advantage and claims to be the first to do so.

Certeon claims aCelera can cut the time required for applications to respond over WANs by 95 per cent. The Linux-based software is compatible with VMware ESX and ESXi.

There are other software-based acceleration products that could run on virtualised servers, but they weren't created with virtualisation in mind or certified to work with VMware as aCelera was, according to Forrester Research analyst, Rob Whiteley.

Virtualisation has proved so useful for boosting efficiency and easing management that it's moved beyond traditional server workloads to include functions such as firewalling, intrusion prevention and now WAN acceleration, Whiteley said. Certeon's move may help break the constraints of cost and complexity that have forced enterprises to limit WAN acceleration to just a few key locations, he said.

"It has had some challenges in reaching a more mainstream audience," Whiteley said.

Although aCelera costs $US2495 and up per site, dedicated appliances commonly cost twice that, he said. And as long as there is a virtualised server at the site capable of running aCelera, all the IT department has to do is download the software to it, Whiteley said. He believes dedicated appliances will become the exception over time.

VMware can automatically scale up and reallocate aCelera's needed resources up to the point where more virtual machines need to be added for it, said Shawn Cooney, director of research at Certeon. Then, by adding more virtual machines, administrators can increase the acceleration capacity as much as needed for certain times of the day or month when application traffic over the WAN will be especially high, he said.

Flexibility would be a key benefit of a virtual WAN accelerator, analyst at Current Analysis, Michael Brandenburg, said.

With dedicated appliances, you had to buy toward what you might possibly need, versus what your typical traffic was, Brandenburg said.

Certeon is pricing aCelera per user, with the basic price covering a certain number of users at a site. The software is available now for VMware and will be available for Hyper-V when that system comes out, which Certeon expects in July. In the future, the company hopes to make aCelera work with other virtualisation platforms such as Xen and KVM (Kernel-based Virtual Machine), Taube said.

The company will also continue to sell its earlier hardware appliances.