By Dave Simpson
Next month, FineGround Inc. is expected to begin shipments of a wide area file services (WAFS) appliance, putting the company in competition with other WAFS vendors such as Cisco (via its acquisition of Actona Technologies), DiskSites, Riverbed, and Tacit Networks.
WAFS appliances, including FineGround’s Velocity-FS, promise LAN-like file access speeds over WANs, as well as reduced bandwidth requirements through the use of protocol (e.g., CIFS/NFS) optimization. WAFS appliances allow companies to consolidate storage from remote offices (as well as mobile users) into data centers, thus reducing management overhead and costs. Files are delivered to remote users as though the files were local.
The Velocity-FS WAFS appliance transforms CIFS requests to HTTP file requests and vice versa.
According to Arun Taneja, consulting analyst and founder of the Taneja Group (which coined the WAFS term), a key differentiator of FineGround’s Velocity-FS versus other WAFS implementations is that it only requires an appliance at the data center, as opposed to requiring appliances at both the data center and each remote location. FineGround refers to this as “data center-only” WAFS.
Although this approach cuts costs, it will in most cases not provide the same level of performance that is available with a dual-appliance approach that includes caching at remote sites, according to Taneja. (FineGround’s Velocity-FS does not provide caching, as do most other WAFS appliances.)
However, FineGround officials argue that for many applications, and the company’s target markets, the single-appliance approach will provide adequate performance.
“The performance issue comes down to application requirements, file sizes, number of file changes, read/write ratios, and other factors,” says Taneja.
Another potential drawback of not having WAFS appliances at remote sites is that you can’t layer storage services on the appliances at branch offices, a feature offered by WAFS vendors such as Riverbed and Tacit.
FineGround’s WAFS appliance front-ends the data-center file and storage infrastructure, sitting in front of storage resources such as RAID arrays, NAS filers, and standard Windows file servers.
FineGround’s Velocity-FS supports the CIFS protocol, as well as Microsoft’s Distributed File System (DFS). NFS support is in development and might be available when the appliance ships in late June, according to Jay Mellman, FineGround’s vice president of marketing. Most other WAFS appliances support both CIFS and NFS.
WAFS appliances can significantly reduce file access times, which are otherwise bogged down by the inherent latencies associated with WANs. For example, Chris Smith, manager of computer services at PMC-Sierra, which is testing a Velocity-FS appliance, says that in one application file access time was reduced from 80 seconds (using native CIFS over a WAN) to 15 seconds with the WAFS appliance.
In general, FineGround claims a 3.3x to 6.6x improvement in file-access time over a 100Mbps T1 link, and a 2x to 9.2x improvement over T1 links, versus native CIFS.
In addition to CIFS and DFS, Velocity-FS supports Microsoft’s Active Directory and Windows NT LAN Manager (NTLM) rights management.
Velocity-FS appliance is priced from $20,000 and depends on the number of concurrent users.
Tacit + Microsoft
Also on the WAFS front, Tacit Networks last month announced an extended partnership with Microsoft that includes joint marketing and technology collaboration, including WAN file serving, file-level caching, and centralized file consistency technologies. Tacit’s WAFS appliance is based on Microsoft’s Windows Storage Server 2003. (A Linux version is also available.) Other WAFS appliances, such as Cisco’s, are available only with Linux implementations.
Greg Grodhaus, Tacit’s chairman and CEO, notes that the advantage of a Windows-based WAFS appliance is that you get all the Windows security and storage features, including end-to-end security, Kerberos authentication, Server Message Block (SMB) packaging, management tools, etc.
For more information, go to www.mi crosoftstoragepartners.com. For case studies on WAFS users, see “Users adopt WAFS for WAN file transfers,” InfoStor, October 2004, p. 12.