SAN Notes Featuring Wire-Speed iSCSI


Internet Small Computer System Interface, iSCSI in short, is a relatively new Internet Protocol-based storage networking standard for linking data storage facilities. Developed by the Internet Engineering Task Force (IETF) iSCSI facilitates data transfers over Intranets and manages storage over long distances by carrying SCSI commands over IP networks.

The oldest legacy equipment and the cheapest new equipment both communicate using the SCSI protocol and were not designed for storage networks. iSCSI promises to connect legacy and cheap hardware to the storage networks of the future. Because of the ubiquity of IP networks, iSCSI can be used to transmit data over local area networks (LANs), wide area networks (WANs), or the Internet, thus enabling location-independent data storage and retrieval.

So it's a big deal that Alacritech, Nishan, and Hitachi Data Systems claim to have enabled wire-speed iSCSI operations by putting their best products forward. Alacritech's 1000X1 Single-Port Server and Storage Accelerator efficiently offloads TCP/IP and iSCSI processing in storage applications. The accelerator uses an application-specific integrated circuit (ASIC) in its processing hardware, which relizes remarkable data transfer efficiency.

According to tests run by eTesting Labs in accordance with its Chariot 4.0 benchmark, the Alacritech accelerator transfers an 8 Kb file 84 percent more efficiently than a comparable NIC from 3COM—specifically, 3COM's 10/100/1000 PCI-X Server NIC. Additionally, the larger the file, the greater the efficiency Alacritech achieved. Alacritech's 1000X1 server transfered a 64 Kb file 1,591 percent more efficiently that comparable servers. The eTesting Labs test attached the Nishan and Alacritech products to top-of-the-line Hitachi Freedom Storage hardware. In the eTesting Labs test, CPU utilization for storage processing was slightly below 8 percent.

Fibre Channel is the benchmark technology for transmitting data between computer devices at a rate of up to 1 Gbps (one billion bits per second). It's especially suited for connecting computer servers to shared storage devices and for interconnecting storage controllers and drives. Since Fibre Channel is three times as fast, it has begun to replace the Small Computer System Interface (SCSI) as the transmission interface between servers and clustered storage devices.

But this has been a costly proposition because Fibre Channel switches are more expensive than Ethernet networking equipment. The price of Ethernet and related products has gone down as mass market PCs were equipped with Ethernet ports and Ethernet networking products reached a price point at which they could enter the home, where their rapid adoption further drove down the price of Ethernet prouducts.

Barry Haaser, Alacritech vice-president of marketing said the company had to prove that it is just as fast as Fibre Channel technology.

"With Alacritech and Nishan on the iSCSI side, and Hitachi Data Systems on the storage products side, we feel we can do that," Haaser said. "IP is pervasive and will provide the foundation for the next generation of storage networks. As long as network administrators can guarantee performance and security, IP becomes the natural choice."

Haaser added that the product begins to allow people to deploy IP-SANs seamlessly.

"We can use this product to move traditional file data or iSCSI block level data," Haaser said. "Nishan handles all the necessary protocol conversions at wire speed."

Click for entire screenshotUsing Intel's Iometer test suite (left), and a 1 Gigabit per second port, the product tests achieved full duplex throughput, a total of 219.64 Megabytes per second adding up traffic in both directions. Haaser explained that in this case, the payload efficiency of iSCSI has been optimized to about 92 percent, therefore utilizing only eight percent of the pipe for protocol overhead.

Randy Fardal, Nishan vice-president of marketing, explained the system in greater detail.

"iSCSI uses familiar networking equipment such as LAN devices. For example, a large financial institution with 300 to 500 IT staff who run Cisco boxes and have beepers have a network that is well understood and well managed," Fardal said. "A Fibre Channel SAN fabric is powerful and should have a good ROI but it has not been deployed. Why? Because these enterprises don't have people who know how to implement it. Futhermore, with a limit of 10 to 20 switches, that's not enough for a 1,000 user LAN. GigE and iSCSI can do that, using IP."

Consequently, Nishan and Alacritech believe that the advent of wire-speed iSCSI will accelerate the deployment of storage networks, especially as Gigabit Ethernet becomes prevalent in metro area networks.

Fardal says he sees a three-stage migration path for customers and that customers could mix and match parts of any of the three phases of development:

Stage 1Click for larger image
Stage 2 Click for larger image
Stage 3 Click for larger image

At the first stage (above), the enterprise has separate NAS and SAN networks, each with different managers and different management software.

In stage two (also above), network administrators still have a separate NAS and SAN, but have introduced an IP fabric to replace the Fibre Channel switches. The network still has the old Fibre Channel storage products, but new products are iSCSI storage products.

In stage three (also above), network administrators use the Alacritech accelerators to attach the NAS to the IP storage fabric, and Nishan's switches enable wire-speed non-blocking access to a variety of devices on a single storage network that should therefore be easier and cheaper to manage.

As long as metro area networks like Yipes!, Telseon, Cogent, and Intellispace continue to provide GigE connections to businesses, the vendors are confident that these new products will find eager buyers.

Production of products
Brocade is also hoping to speed the adoption of storage networks, but the company is betting on education, rather than return-on-investment. Brocade recently launched a SAN education initiative in China. In addition to working with local trade groups, Brocade will sponsor a SAN scholarship at Shanghai Jiao Tong University.

Sony released new AIT-3 tape drives featuring 2.6:1 data compression that allows its 100 GB tapes to store 260 GB of data. The company also claims to have demonstrated the ability to store 6.5 Gbits in a single inch of tape—paving the way for technology advances up to the sixth generation (AIT-6). An internal AIT-3 drive is priced at $3,985, while an external drive is priced at $4,225.

SANcastle unveiled a two-port 1U rackmount Fibre Channel and Ethernet media converter. The GFS-2 is set to be released this month for about $15,000 per unit.

In the data center services space, Rackspace Managed Hosting debuted a security alert website for customers. Dubbed, the site is designed to provide customers with information on security threats to their servers. The site also allows customers to log on with a password and view current billing status, network status, bandwidth use, the status of trouble tickets, and useful articles. Rackspace hopes to sell a subscription security alert providing subscribers with the details of the latest viruses and vulnerabilities.

Mergers, acquisitions, and spending money
Webcaster Visual Data Corporation (Nasdaq: VDAT) acquired rival in an all-stock transaction.

Chaparral Network Storage, a storage appliance manufacturer, raised $12 million in continuing financing, bringing its total funding to $41 million to date. Last year, Chaparral's 2Gb/sec Fibre Channel Javelin RAID controller was selected to be part of JMR Electronic's best-of-breed E-Z SAN bundle.

Alacritech (featured earlier in this article) completed a $25 million second round of financing with the closing of a $13 million investment.

Storigen, a provider of distributed storage systems, closed a $25 million second round of investment and Maximum Throughput of Quebec, finished up a $7 million first round of financing to add to its $4 million startup investment round. Maximum Throughput's first product, Sledgehammer, delivers 1922 Mbits/sec over TCP/IP.


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