Big things have been predicted for iSCSI for what seems like years, with each new year bringing with it claims that iSCSI would finally hit the big time. So has reality finally caught up with the hype? Analysts appear to be warming to the idea that iSCSI's time may have arrived at last.
"iSCSI usage now appears to be growing steadily," says Tony Lock, an analyst at UK-based Bloor Research.
John Webster, founder and senior analyst at Data Mobility Group of Nashua, N.H., agrees that the sector is finally warming up.
"It's about time that the iSCSI opportunity showed some life," he comments.
The most enthusiastic of the bunch is Milford, Mass.-based Enterprise Strategy Group's Steve Duplessie.
"iSCSI is booming," says Duplessie. "We'll be tracking over 10,000 production implementations by the end of the year, and probably as high as 25,000 more 12 months after that."
IDC has been reporting strong iSCSI growth since early 2004, with Network Appliance of Sunnyvale, Calif., comfortably in the lead with greater than 40% market share. NetApp says that almost half its systems now ship with the iSCSI target enabled.
Duplessie sees smaller vendors also leading the iSCSI charge. Overland Storage of San Diego is shipping more than 500 iSCSI backup targets each quarter. LeftHand Networks of Boulder, Colo., is said to have hundreds of customers believing in iSCSI.
EqualLogic Gets High Marks
Duplessie says that EqualLogic of Nashua, N.H., has more than 500 customers almost all of them big shops.
"I love what companies like EqualLogic and Compellent are doing building super-intelligent, very high-end systems that a monkey can run and a pauper can buy," says Duplessie.
Other analysts share his enthusiasm for EqualLogic's take on IP SANs.
"iSCSI vendors like EqualLogic are finally getting their due attention," says Webster.
EqualLogic's PS Series family of storage arrays, for example, is a native iSCSI SAN solution with fully integrated storage management capabilities. Each array comes with redundant fault-tolerant hardware and includes automatic storage-management software. Multiple arrays can be combined to form a 100 terabyte-plus grid. According to EqualLogic, the protocol has evolved well beyond its initial SMB market and is now being used to serve up data to applications such as e-mail, ERP, CRM, student information systems, digital media archives and e-commerce database systems.
John Joseph, EqualLogic
"iSCSI surprised everyone by finding its way into the enterprise," says John Joseph, Vice President of Marketing at EqualLogic. "In 2005, this trend continues, as more large IP SANs running business critical applications are deployed."
He characterizes the market as having two distinct iSCSI product categories: cheap SAN systems for the masses, and robust alternatives to Fibre Channel SANs for enterprises. Thus, iSCSI is transitioning from a single-controller JBOD with an iSCSI wire to enterprise-quality systems with management tools and other higher-end features.
"The myths about iSCSI reliably and performance have been debunked by customers themselves," says Joseph. "Businesses of all sizes, government agencies, colleges and universities, hospitals and healthcare benefits providers are using iSCSI to build centralized SANs on the order of 20, 30 and 50 terabytes."
Fibre Channel's Role
What does this mean for the Fibre Channel (FC) marketplace in the long run? Joseph thinks that both standards will coexist. FC, he says, will occupy the very high end, while iSCSI takes over in the vast majority of midrange storage deployments. He confesses, however, that iSCSI is not yet ready to host the most demanding real-time transactional databases. This could change rapidly, though, as higher-speed Serial Attached SCSI (SAS) drives and 10 Gigabit Ethernet arrive on the scene and are integrated into future systems.
Companies such as Brocade Communications Systems and Cisco Systems, both of San Jose, Calif., continue to occupy a less upbeat position on iSCSI. Brocade thinks iSCSI has a role as a complementary technology to Fibre Channel, but that it will principally be used to enable lower-cost servers at the edge of an enterprise network to connect to managed storage in SANs. For highest performance and greatest reliability, FC will continue to be the primary choice.
Brocade CTO Jay Kidd even sees iSCSI as a way to increase FC's scope.
"In small companies, who typically do not purchase Fibre Channel SANs, iSCSI and NAS will drive adoption of a networked storage model, which ultimately could grow to include some Fibre Channel ports for mission-critical applications," says Kidd.
Brocade already offers a Multiprotocol Router that bridges iSCSI traffic into a Fibre Channel SAN. In addition, the company plans to extend iSCSI support to its Tapestry family of IT automation products.
"Our goal is to increase the size of the storage network opportunity, regardless of protocol," says Kidd. "We believe that the technology has improved to the point where iSCSI deployment will enjoy a gradual growth alongside the growth of Fibre Channel SANs."
Waiting for Cisco
Cisco, meanwhile, remains hesitant about iSCSI. Many thought the leader in IP networking would be quick to champion the protocol. But while it has added plenty of iSCSI support, its storage offerings are still focused largely on Fibre Channel.
"iSCSI complements other protocols, including Fibre Channel, by extending storage area network (SAN) benefits to mid-range servers," says Rajeev Bhardwaj, product line manager for Cisco's Storage Technology Group.
Cisco has given some indication of its strategy with the release of the multi-protocol Cisco MDS 9000 product line. It supports FC, IBM Fibre Connection (FICON), Fibre Channel over IP (FCIP), and iSCSI. The company feels that customer business and operational requirements will influence how iSCSI is to ultimately be deployed. iSCSI attached servers, for example, may be deployed with an iSCSI gateway to Fibre Channel SAN, or with native iSCSI connectivity to a storage array.
"The decision to use iSCSI is driven by cost-performance tradeoff," says Bhardwaj. "Each connectivity option has its own performance and cost profile, enabling customers to optimize storage networking costs with an integrated director class storage networking platform."
Not all storage network clients, for example, need or can utilize a full bandwidth 2Gbps connection. This raises concerns about the cost of provisioning redundant 2Gbps connections to lower-cost midrange servers. Using protocol-agnostic products such as MDS 9000, users have the option of 2/1 Gbps wire rate FC, 2/1 Gbps shared Fibre Channel, 1 Gbps iSCSI and 100 Mbps iSCSI connections.
Bhardwaj thinks Fibre Channel is more suitable for high-performance applications such as on-line transaction processing (OLTP) and database applications, whereas FICON is suitable for mainframe connectivity. iSCSI, on the other hand, is better for cost-effective SAN connectivity for application servers with midrange performance requirements.
"Some of the large vendors still seem to be waiting for the iSCSI market to reach some sort of critical mass," says Webster. "Cisco is something of a bellwether vendor for iSCSI. Right now, they appear to be biding their time with FC switches while the iSCSI opportunity germinates."
Duplessie, however, thinks the ultimate bellwether has been Microsoft.
"Microsoft should take a lot of the credit for iSCSI's success," says Duplessie. "They gave away the driver, and lo and behold, people started using it. iSCSI is awesome for those applications that don't require the performance and cost of a full Fibre Channel SAN, which is about 80% of the world."
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