The newest thinking behind file virtualization is the concept of the File Area Network (FAN), which backers claim offers a better answer to extending complex and costly SAN and NAS infrastructures. But while there may be a general consensus as to what FANs should accomplish, there's a wide variety of views as to how they should operate.
Acopia Networks, for instance, offers as a basic approach a centrally managed file-based storage system with massive scalability to enable lifecycle management, content management and content-addressable storage. A key element in Accopia's approach is the Global Unified Namespace that offers a single access point in the storage infrastructure that preserves existing physical file systems but still provides access as a single shared entity.
Newcomer Attune Systems, on the other hand, wants to see more discovery, policy management and non-disruptive migration in the mix. It claims to have the only such system available for Windows in the form of the Maestro File Manager appliance.
Much of the development work on FANs is being led by the File Area Network working group, part of the Storage Networking Industry Association (SNIA). The group is still working out a meaningful definition that can be delivered to other storage industry standards committees. The group consists of the leading storage vendors, such as EMC, HP, IBM, Netapp, Brocade and Accopia. Another new firm, Njini Inc., recently joined the group, contributing its Information Asset Management metadata and file automation technology.
It would be a mistake to think of FANs as a replacement for SAN or NAS architectures. An adjunct is a more appropriate description. And if the powers-that-be ever do decide on exactly what a FAN is and how it should be implemented, it should go a long way toward bridging the gap between applications and file resources, and push storage scalability onto a global scale.