Q: What is a File Area Network?
A: A FAN is a systematic approach to file-related advances occurring throughout today's enterprises. A FAN is about applying methodology and repeatable architectural framework to disparate IT activities.

Q: What makes up a FAN?
A: The building blocks of FAN architecture today are defined as:

• Storage devices
• File serving devices/interfaces
• File systems
• File namespace
• Clients (desktops, workstations, and so on)
• Connectivity between client and namespace
• File enhancement services-admin/end user

Q: Why is the FAN concept so important?
A: The explosion of file data and corresponding technology requires a coherent strategy to ensure interoperation within and between all file components in the enterprise.

Q: What are the technologies that are driving the FAN?
A: The majority of these technologies can be classified as follows:

• Wide Area File Services (WAFS)
• WAN optimization and application acceleration
• Distributed and clustered file systems
• Network File Management (NFM)/file virtualization
• File/document management software
• File classification software
• File data placement/movement controls

Q: Why do customers need a FAN?
A: FANs help to improve enterprise flexibility and agility by:

• Making file location and movement transparent to users
• Providing deterministic and opportunistic file migration
• Eliminating downtime and helping to ensure business continuance and disaster recovery

FANs also help reduce Total Cost of Ownership (TCO) by:

• Consolidating branch office IT infrastructure
• Eliminating the cost of remote data backup
• Centralizing file storage

FANs also contribute to improved compliance by:

• Simplifying centralized file access management
• Intelligently migrating files based on ILM policies
• Maintaining file management and security protocols during WAN optimization

Q: What does Brocade provide in the way of FAN infrastructure?
A: Brocade provides solutions based on point products, architectural best practices, and services. Key solution areas include file migration, replication, and consolidation in both data centers and branch office environments.

Q: What is different between SANs and FANs?
A: While there are definite correlations between FANs and SANs in their basic concepts, services, and customer benefits, the components are very different. In a SAN, the core component is a fabric, while the core component in a FAN is a namespace. The key difference with a FAN is how information is presented rather than the physical device relationship.

Q: What is a namespace?
A: The presentation, access, and general organization (directory structure) of any given file system's data is referred to as the namespace. The namespace is one of the foundations needed to define and build a FAN.

Q: Are there different types of namespaces?
A: There essentially are three types of namespaces:

• Non-shared namespaces are user-level presentations of information corresponding to a file system image tied to a physical machine with no sharing of information across multiple file system images.
• Shared namespaces-such as those from Rainfinity, Acopia, NeoPath, and Microsoft DFS-represent a subset of an enterprise's physical file presentation environment that has been federated so that information can be shared across multiple homogeneous devices.
• Global unified namespaces, as provided in Brocade Tapestry StorageX, are heterogeneous, enterprise-wide abstractions of all file-level information-open to dynamic customization based on administrator-defined parameters.

Q: How do SAN, NAS, and FAN fit together, or do they?
A: Most of the leading file servers and NAS devices have Fibre Channel (SAN) storage on the back end. In addition, all storage approaches have block data formats at their core, and all of these block storage spaces are managed in some way by some sort of file system, whether it is NTFS, UFS, or a database management system. So ultimately, the distinction of SAN and NAS is becoming obsolete. SANs provide management for data in its block form to and from the storage and file server/NAS, while the file servers/NAS (part of the FAN) serves it out to the FAN, and the FAN provides management, delivery, and virtualization to and from the user.

Q: What essential services are delivered with a FAN?
A: In addition to basic storage services, FANs can support such services as:

• Migration: Move files non-disruptively underneath shared namespaces or global unified namespaces.
• Replication: Non-disruptively replicate data between resources and geographies.
• Placement: Place file-level data on a physical device based on its attributes.
• Access continuity: Allow non-disruptive access to abstracted file-level information.
• Information classification: Enable content-level indexing of all information that then supports policy-based controls, access, and retention.
• FAN extension: Extend access to the FAN across geographies supporting wide area connectivity into its namespaces.