The case for mixed-media NAS towers
Imagine a network-attached storage (NAS) tower that combines CD-ROM and DVD drives, hard disks, tape drives, removable storage, and other types of SCSI devices in a a customized array designed specifically for enterprise or workgroup applications. The platform would be flexible and scalable, managed by a Web interface and would support all network protocols simultaneously.
By Charles Kronauer
Sound like a pipe dream? Well, for the most part, the technology to create mixed-media NAS towers is available today. However, the time frame for actual product delivery is still in question.
Network-attached CD-ROM servers established NAS devices as viable components in local area networks. Their rapid market acceptance was, in part, due to the unique set of benefits network-attached CD-ROMs offer. Applications that distribute historical information, graphics, and other "fixed" data helped fuel the market growth.
According to Disk/Trend Inc., a storage market research firm in Mountain View, CA, more than half of all CD-ROM towers shipped in 1997 were network-attached, as opposed to host-attached. And by 2001, Disk/Trend expects network-attached solutions to account for more than 80% of CD-ROM tower shipments.
Hard-disk caching in CD NAS towers is the technological step that could make mixed-media NAS towers a reality. Disk caching makes it possible to copy CD or DVD content to a hard disk co-located within the tower. The copied data is accessible directly over the network from the hard disk, providing tremendous speed benefits to users accessing the data.
Thin servers pave the way
Thin-server technology will also play a key role in the evolution of mixed-media storage towers. By embedding network functionality in peripheral devices and bypassing general-purpose file servers, device performance can be optimized by dedicating devices to single tasks. This also simplifies device implementation.
Thin-server technology has also proven that the physical location of data storage (and/or data delivery) devices is almost irrelevant. They can be located in a workgroup, next to an application server in the data center, or in a branch office. What`s more, thin-server-based NAS solutions already exist for a variety of media types. Over the past year, low-cost NAS solutions have been introduced for disk arrays and for removable media devices such as tape libraries and Jaz drives.
Advances in thin-server technology have created a new mode of thinking. Users now know that it`s possible to plug multiple types of devices into the network with little effort.
In theory, with a thin-server approach, it shouldn`t matter what type of tower a drive resides in or what other drives reside with it; towers are just repositories for a mixture of drives--CD, DVD, disk, tape, removable, etc.
So, it`s not a stretch to think that mixed-media network towers are just around the corner. Yet the question remains, When will plug-and-play mixed-media NAS servers become available?
The answer: When the market demands it. It`s clear that NAS can be successful when a specific use is identified, such as the way CD NAS now dominates fixed-data distribution over networks.
But despite bright market predictions for the future, NAS products for alternative media types have not enjoyed the rapid market growth of CD-ROM.
Thin-server technology makes it possible to combine many media types in a single package. Yet, until a specific set of benefits and applications are identified for mixed-media towers, they will probably be relegated to niche markets.
Mixed-media tower benefits
Access to data on various types of optical and magnetic media already exists today. File servers, CDs, tape backup, and even networked removable media drives reside in different locations, "networked" in different ways. But the migration from such single-media NAS solutions to mixed-media towers will result in a number of benefits:
1) Simplified connectivity. With a thin-server architecture, various types of drives work together. There is one network connection, one installation procedure, one network management tool, and one IP address. This type of mixed-media tower solution could be fully operational within minutes of taking it out of the box.
2) Customized solutions. A mixed-media tower can be easily tailored to specific work flows or applications and modified as storage requirements change. Drives show up as nodes on the network. They can then be made into mapped drives or implemented as a set of applications launched from a Web browser with a single mouse click.
3) Scalability. The configuration of network storage towers (e.g., swapping a CD-ROM drive for a tape drive) can be easily changed according to users` needs. With thin server-enabled towers, drives can be hot-swapped in minutes.
4) Flexibility. Because it bypasses the file server, a NAS tower can be placed anywhere on the LAN, reducing network traffic across the backbone. Support for removable media allows for portability and physical security of data, and the single tower device reduces space requirements.
5) Simplicity. Non-technical staff can easily set up and maintain most NAS solutions, including mixed-media NAS towers. Plus, networked storage does not have to be a major capital purchase, as it would be if you added a fully functional file server and server-attached drives.
Despite the potential benefits, the ultimate success of mixed-media NAS towers will likely be determined by application requirements. For example, mixed-media NAS towers could be used to support file servers, acting as primary storage repositories. Or, they could be used for backup or archival applications, simultaneously using various types of media.
Because mixed-media towers will be Web-enabled, they could fill the role of Intranet servers. Hard disks would be used for the interface and parts that need to be changed, and CD or DVD drives would serve up corporate data, images, parts lists, etc.
And a mixed-media tower could be the perfect "data center in a box" for corporations that want an easy way to roll out new applications to branch offices.
Charles Kronauer is the senior product marketing manager for storage at Axis Communications, in Redmond, WA.