Last week Cisco Systems released the File Engine Series, network appliances that rely on technology based on software Cisco gained in its August 2004 purchase of Actona Technologies. The technology--called Wide Area File Service (WAFS)--lets far-flung corporate environments consolidate data that would otherwise reside at branch offices into their main data center.
Comprising three appliances (and a piece of management software), WAFS is implemented by placing a Cisco Edge File Engine appliance at each branch office and the core Cisco File Engine back at the primary data center, where it's directly connected to file servers or storage gateways. The software component, Cisco WAFS Central Manager, provides a single-point monitoring solution for the entire WAFS infrastructure. In a large infrastructure, WAFS Central Manager is installed on a dedicated appliance; in smaller environments, WAFS Central Manager can coexist with the core Cisco File Engine on one appliance.
Communications over the WAFS network occurs via standard file-system communications protocols: Common Internet File System (CIFS) for Windows networks and NFS for Unix networks. This means that the implementation is effectively invisible to the WAFS users; no software needs to be installed on any client or server computers to make the WAFS data accessible. Furthermore, all authentication mechanisms that a company uses to maintain control over who can access data are also transparent to the Edge File Engine, so that the company's existing security model isn't disrupted.
The Edge File Engine maintains a cached view of the centralized data storage. Through a combination of protocol caching, compression, and network-optimization techniques, the Edge File Engine can deliver any data it finds in that cached view at speeds near enough to actual LAN wire speed so as to be unnoticeable to end users.
An interesting feature that makes the WAFS technology possible is a technique called Policy-Based Pre-Positioning. By using this feature, an IT department can push needed files out to the Edge File Engines that reside in the branch offices. For example, the release of a new Windows service pack could be pushed out before business hours to all offices that had Windows client computers. By executing one command from the central console, you could make the software locally available to every branch office.
The WAFS solution is costly; the core File Engine lists for $12,500 and includes a license for 50 branch-office users. Additional licensing, in 50-user packs, is $4500. So, on the surface, when you look at just the implementation costs, WAFS is far more expensive than keeping a file server in each office. However, to accurately evaluate Cisco's solution, you need to weigh its hardware and software costs against the cost of supporting servers in branch offices, backing up their data, physically securing the data, and the overall administrative costs associated with maintaining different servers scattered throughout the corporate enterprise. When viewed in this light, Cisco's File Engine Series looks like a bargain for an IT department that's tasked with maintaining an infrastructure that includes many remote offices.
