Expand Networks is expanding its WAN acceleration and WAFS boxes to the fattest yet - its latest Accelerator 7940 appliance has 3TB of storage built-in. The company said that this will help large organisations in their server consolidation.

It's all about bringing more data back to the relative safety of the data centre, said Chris Williams, Expand's chief marketing officer.

"It was driven by our customers wanting to centralise the data from hundreds or even thousands of remote offices," he said. "It doesn't change the need for a box at each end of the link, but it means the data centre needs fewer boxes."

The 7940 is a 2U rackmount device, with redundant power supplies, six hot-swappable 500GB hard drives, and Expand's modular Compass operating software. The drives can be configured as RAID, and the device can support up to 16GB of RAM and a second processor.

A neat trick is it stores all its system data on a bootable flash memory card - if the box dies, you swap the card into a spare unit and it will boot with your original configuration intact, Expand claimed.

At just under $25,000, the 7940 costs $6000 more than Expand's next largest device, which only has one 500GB drive.

The 7940 can handle up to 45Mbit/s of WAN throughput, Williams said, allowing it to support T3, E3 or DS3 links.

That, contended Jeff Aaron, product marketing director at rival WAN optimiser Silver Peak, is where the 7940 still isn't ready for big server consolidation projects.

He said that being able to handle the 155Mbit/s throughput of an OC-3 line (as his company's NX appliances are claimed to do) is a key requirement.

"Several vendors have the ability to accelerate the basic TCP protocols, so that's not where the excitement is going to be," he added.

"It's going to be how do you bring all that back to the data centre, for example on an OC-3, and it's going to be how you handle data centre to data centre issues such as backup over a 45 to 155Mbit/s pipe."

Find out more: IDG's WAN Optimisation Conference is on 26th September 2006 in London.