Catch the next wave: 2Gbps FC SANs

Next-generation Fibre Channel SANs could benefit database/transaction servers, disaster-recovery applications, and imaging environments.


The next wave in the evolution of storage area networks-2Gbps SANs-is already being embraced by early adopters. Those companies consist primarily of rich-media environments, including video post-production and streaming media.

But rich media is just a beachhead for more mainstream adoption. The motivations that moved rich-media companies to deploy 2Gbps SANs are the same forces driving many enterprise environments today: improved network performance, increased throughput, future scalability, and return on investment.

High-performance 2Gbps SANs are not just for niche applications. Rich-media environments provide a bellwether for the benefits of 2Gbps SANs in more-common enterprise environments.

Surf the SAN

Deploying a SAN is like learning to surf. The first time out, most surfers don't paddle into the swell of big waves. Instead, they start small, practice how to handle the board, strengthen their muscles, and learn by observing the movements of more-advanced surfers.

The same is true of SANs. Most companies start small, with relatively simple SAN islands that provide immediate results, while learning to mimic the moves of the early adopters. Eventually, just as most surfers want to ride the big waves, many SAN sites want to deploy large SANs that consolidate storage for hundreds, even thousands, of heterogeneous servers. But this takes time, experience, and learning cycles.

The first steps can be painful. In the early days of SANs, rich-media companies prematurely tackled medium-sized waves and wiped out. These companies-which include nonlinear editing, streaming media, video-on-demand, and streaming audio markets-paddled out again and gradually gained enough experience to learn how to successfully deploy and manage medium-sized SANs.

Rich-media companies persisted with SAN deployments for one simple reason: They needed extremely fast access to very large storage depositories to reduce the wait time of high-priced film and sound editors.

From Hollywood to Main Street

The back lots of Hollywood production companies are not much different from the back offices of Main Street corporations. Both need to deliver products and services quickly and at low cost. To accomplish this, they must have extremely fast access to very large data depositories-whether these involve editing special effects or accessing a company's intellectual property assets in structured data applications like CRM or ERP.

Corporate America, like Hollywood, increasingly has more data in more locations being processed by more people simultaneously, making fast access no longer a luxury. Rather, it is becoming a requirement of running an efficient business and extracting maximum return on investment (ROI) from storage infrastructures.

The rich-media industry is deploying 2Gbps Fibre Channel infrastructures that offer increased bandwidth and improved performance. Uncom pressed HDTV, which requires more than 1Gbps bandwidth, is now possible with 2Gbps SAN infrastructures. In addition, twice the number of servers, or servers with twice the bandwidth requirements, can be supported.

Follow the leaders

The same solutions that proved successful for the rich-media industry can solve many problems currently facing mainstream enterprises. And again, enterprise customers are starting small but thinking big. Although a SAN is a network, the underlying traffic is storage traffic, i.e., block-level rather than IP-based traffic. Starting small allows users to reap a better ROI from the technology, because the price/performance curves of SAN equipment are accelerating fast. From some vendors, 2Gbps components represents only a 20% price premium over 1Gbps components-while adding up to 100% more bandwidth and performance.

Enterprises are also learning to choose an infrastructure that is scalable, as it applies to servers, hosts, and infrastructure. Low initial investment in SAN infrastructure is key, since not all SAN islands will evolve into a very large SAN. The SAN infrastructure should be able to network a large amount of switches to support scaling before expensive backbone-based infrastructure is required.

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Also, as SAN performance increases and prices decrease, enterprises should consider deploying more than one vendor within their SANs, which will help prevent users from getting locked in to just one vendor. Multi-vendor deployment will also enhance vendor competition, exerting price pressures and forcing innovation. It will also help ensure interoperability.

What are likely to be the next enterprise applications to catch the wave of 2Gbps SAN deployment? Because 2Gbps SANs offer both increased bandwidth and performance, the two areas that will benefit most are bandwidth-intensive applications and business-critical applications. In addition, since 2Gbps devices are backward-compatible with 1Gbps devices, deploying high-performance switches is an economical method of improving the performance of many existing SANs.

The following are the applications/environments where 2Gbps SANs will first take hold:

Database/transaction servers: Transaction servers used for e-commerce applications are special-case data servers, where a transaction may require the locking and unlocking of diverse records over a relatively long period of time with complete rollback capability. Naturally, with the explosion of the Web and certain e-commerce applications, bottlenecks are appearing. At 2Gbps, the number of read/write transactions is improved by 30% to 100%, depending on the data block size-with the largest gains seen between 4KB and 16KB. By doubling the I/Os per second that can be processed, a data center can double its efficiency in addressing online transactions. These improvements at the server and storage level translate into cost savings and efficiency gains for enterprises like banks, e-retailers, and online trading houses.

Disaster recovery: Whether backing up data to tape libraries or mirroring to a remote site, the explosion of data and the increasing demands of data access mean that the backup window is shrinking rapidly. Potentially doubling the bandwidth with 2Gbps speeds can cut the backup window in half and reduce the risk of exposing corporate information assets. By pairing a 2Gbps switch with newer techniques of using disks as backup media, very large data sets can be backed up with unprecedented efficiency.

Medical imaging: The move to digital data in hospital environments means that some medical-imaging applications are now using SANs to store the data. With the high contrast and high resolution required from X-ray and MRI images, Fibre Channel SANs have already added efficiency for IT administrators in large medical centers. An upgrade to 2Gbps in an average medical-imaging center could mean saving 40 minutes in image download time when compared to a 1Gbps SAN. Radiologists or oncologists could spend more time on their diagnosis and process more patient images, improving both patient care and providing quick ROI.

SANs can improve storage management for various types of companies in many different industries. The technology will continue to improve, prices will continue to drop, and interoperability will provide customers with a choice of vendors. While 2Gbps SAN deployments now represent the "bleeding edge," it won't stay that way for long.

Stuart Berman is chief technology officer at Vixel Corp. (www.vixel.com) in Bothell, WA.

This article was originally published on August 01, 2001