Expand Introduces WAFS for Windows Server Consolidation

by Alex Woodie

With the era of server consolidation in full swing, most people agree this strategy can bring real benefits to data center operations. However, with fewer local resources available for use, organizations need to ensure that wide area network (WAN) links can handle the increased bandwidth demands that result when applications are centralized. Expand Networks, a manufacturer of network compression and acceleration devices, this week launched a new range of wide area file services (WAFS) products aimed at decreasing WAN traffic following consolidation of Windows servers.

Figures from Gartner show that server consolidation is on the mind of practically every CIO, and that many of them are acting on it. According to Gartner, 60 percent of enterprises have a server consolidation project underway, and another 28 percent are looking into consolidation. "The economic benefits of consolidation are very real," says Joe Skorupa, a Gartner research director, "but can only be reaped if application performance delivered to remote users remains satisfactory."

During a server consolidation project, the WAN becomes one of the key elements to maintaining satisfactory application performance. It's pretty obvious when you think about it: applications are no longer running on the local server, but on the much larger centralized server. This provides very real benefits to administrators and operators, who no longer must spend their resources maintaining dozens or hundreds of far-flung local servers. But instead of utilizing the nearly unlimited bandwidth of a 100-Mbps LAN, application I/O now must travel over the T-1s, T-3s, or frame relay links that make up a WAN. The capacity of a T-3, the granddaddy of WAN links with 45Mbps of capacity, pales in comparison to even the most basic Ethernet LAN, with 100 Mbps of capacity.

This sudden reliance on WAN links is where Expand Networks new line of Accelerator (Expand Networks' product nomenclature) offerings comes into play. While Expand's network accelerator devices previously delivered performance improvements by a factor of four-to-five times on WAN capacity, and its software could provide quality of service (QoS) packet-shaping to keep bandwidth hogs like FTP in check, applications served over a WAN using an Accelerator still can not achieve the same level of performance as the same applications hosted on a local server over a LAN.

"Even if you have enough bandwidth through compression, and use QoS packetshaping, you still have a problem using that bandwidth because the applications are chattering like a ping-pong ball--it takes a long time to complete a transaction," says Ariel Shulman, the vice president of product management at Roseland, New Jersey-based Expand Networks.

Expand's solution to this bandwidth problem is a new line of WAFS-enabled Accelerator devices. These devices include the same tried-and-true compression and QoS packetshaping capabilities that users have come to expect from Expand. In addition to these capabilities, the devices feature large hard drives and a Linux-based operating system, which are used to provide local file-storage and file-, print-, DNS-, and DHCP-serving capabilities.

Instead of using the WAN to send files from the central server to remote users, files are cached locally on the new line of Accelerator devices. This dramatically increases application response time, and enables users in remote offices to continue working even during server and network outages, Expand says.

Shulman says organizations gain productivity improvements by replacing their remote Windows servers with Expand's Linux-based WAFS devices, and using the Expand View software to centralize administration of the devices.

"You're telling me to take out 200 servers and put in 200 accelerators. What did I gain? We know it's much easier to manage 200 Expand devices than 200 servers," he says. "If you wanted to upgrade to Windows 2000, it's a heavy kind of task. You can ask the ExpandView Server to do that for you, and it can even be done in off hours."

The basic term for this approach is called WAFS, while the specific protocol that Expand uses to accomplish this is the Common Internet File System (CIFS), a file-sharing protocol developed by Microsoft. "The equivalent to CIFS in the Unix world is called NFS. We currently don't support NFS, although we may be adding this," Shulman says. "At end of the day, most employees in the branch offices are not supporting Unix. They're using Windows."

By the end of September, Expand expects to start shipping its first three WAFS devices. These include the Accelerator 4920 Series, which has a 160GB hard drive, provides a total throughput of up to 2Mbps, is designed to support up to 10 remote sites, and should sell for about $4,500. The 6910 Series will be geared for the smaller regional data center, support WAN speeds of up to 10Mbps, utilize a 500 GB hard drive capacity, and sell for $12,000. The 6940 Series will be geared for large data centers, support up to 200 remote sites, support WAN speeds of up to 20Mbps, have a 500 GB hard drive, and sell for about $20,000. All three devices are currently in beta tests. For more information, visit www.expand.com.