Expand Networks last week announced new models of its WAN compression devices with capacity that can be upgraded gradually so customers don't need to keep buying new hardware.Expand Networks\u00a0last week announced new models of its WAN compression devices with capacity that can be upgraded gradually so customers don't need to keep buying new hardware.The two new boxes, Accelerator 4810 and Accelerator 6810, fill gaps in the company's product line that forced some customers to buy higher-capacity devices than they needed. Now customers can buy a device that more closely fits their current needs and leaves the option to buy more capacity later.Customers must buy at least two of the Expand devices and place one at each end of a WAN link that they want to speed up. The devices sit between LANs and WAN routers and compress traffic destined for WAN locations that also have Expand devices. The Accelerators can compress at different rates to match the bandwidth available on the line, so a 256K bit\/sec Accelerator would be suitable for a 256K bit\/sec line. Expand says its equipment boosts network throughput between 100% and 400%.Before the two new boxes were introduced, Expand's Accelerator 1800 topped out at 256K bit\/sec, and the lowest speed of the company's next-sized box, the Accelerator 4800, was 2M bit\/sec. If a customer wanted to support a 512K bit\/sec link, he had to buy a 2M bit\/sec 4800. Now he could buy a 512K bit\/sec 4810 for about $5,000 less and still have the option to increase its capacity by paying a licensing fee.O'Reilly Auto Parts in Springfield, Mo., has installed Accelerator 6810s at its headquarters and its back-up data center in Dallas to speed up a 12M bit\/sec frame relay line between the two that was running at capacity, says Dave Steinle, systems management team leader for O'Reilly. Now the connection runs at 75% to 80% of capacity, staving off the need for a bigger connection.Without the Expand gear, the company was facing an additional 6M bit\/sec in bandwidth at a cost of $2,700 per month, Steinle says. With transaction data ever increasing, he says he expects that O'Reilly will have to buy more bandwidth at some point. When it does, he says Accelerator 6810s can be upgraded to handle the additional traffic.Expand competes mainly against Peribit, whose gear is similar in function. But the companies say they use different methods to reduce traffic. If customers don't want to buy a dedicated compression device, they can implement compression on their routers, an option that might affect route performance.Accelerator 4810 ranges in speed from 256K to 6M bit\/sec and in price from $4,000 to $20,000. Accelerator 6810 ranges from 2M to 45M bit\/sec and from $15,000 to $45,000.