Tip

What you need to know about 10 GigE IP SANs

What you will learn: This tip provides an overview of the state of 10 GigE today, outlines the benefits and limitations of 10 GigE and offers some insight into the future of IP storage networking.

If faster is better for storage area networks

    Requires Free Membership to View

(SAN), 10 Gigabit Ethernet (GigE) is the next logical step up. It is beginning to arrive, but it is still definitely in the early adopter stage.

10 GigE is defined under the 802 standard (802.ae) and uses the same MAC protocol, frame sizes and format as regular Ethernet. However, unlike the older versions, it doesn't rely on the Carrier Sense Multiple Access/Collision Detect protocol (CSMA/CD) to prevent network contention because all connections are full duplex.

More iSCSI SAN information
ISCSI vs. FC explained 

Can iSCSI crack the enterprise? 

Secure iSCSI storage
Ultimately, the promise of Ethernet iSCSI SANs is integration. By using Ethernet for LANs, WAN and storage area networks (SAN), companies theoretically can simplify infrastructures, improve management and reduce costs. While some companies are moving in that direction, the effort has been hindered by the fact that the current standard is 1 GigE, which is much too slow for many applications.

You can buy 10 GigE IP SANs today from a few vendors, such as Nimbus Data Systems, Intransa and Lefthand Networks. However, many of the vendors are small and the products are still new.

Today, 10 GigE SANs are most attractive for what analysts call "corner cases" -- users with highly specialized needs. Among the early adopters have been media companies that need to move a lot of large files, firms looking to back up server farms using a D2D strategy and a few places looking for a very high bandwidth path between servers.

For the average user, there are cost and connectivity issues that detract from 10 GigE's' potential. Even though 10 GigE offers the promise of lower cost SANs, prices are currently considerably higher than for Fibre Channel and 1 GigE Ethernet. Connectivity is hampered by the fact that most servers today are not 10 GigE ready, although adapters are available.

Another key element in 10 GigE's adoption is cabling. The early versions relied on fiber cable, however, 10 GigE can use copper cabling. Cat 5e unshielded twisted pair can be used over a distance of about 180 feet. Augmented Cat 6 and regular Cat 7 shielded twisted pair works for up to 300 feet. Meanwhile, optical cable connections can reach up to 25 miles, compared to 3 miles for 1 GigE.

Some enterprises are looking to the future by installing 10 GigE compliant cabling in upgrades or new construction even though they are still using 1 GigE.

Meanwhile, work on 100 GigE moves forward, albeit slowly. The latest hitch is a division in the IEEE committee defining the standard between those who want to go directly to 100 GigE and a group that wants to insert a provision for 40 GigE into the specification. In any event, it will probably be at least five years before 100 GigE (or 40 GigE) enters the SAN market.

About the author: Rick Cook specializes in writing about issues related to storage and storage management.


This was first published in August 2007

There are Comments. Add yours.

 
TIP: Want to include a code block in your comment? Use <pre> or <code> tags around the desired text. Ex: <code>insert code</code>

REGISTER or login:

Forgot Password?
By submitting you agree to receive email from TechTarget and its partners. If you reside outside of the United States, you consent to having your personal data transferred to and processed in the United States. Privacy
Sort by: OldestNewest

Forgot Password?

No problem! Submit your e-mail address below. We'll send you an email containing your password.

Your password has been sent to:

Disclaimer: Our Tips Exchange is a forum for you to share technical advice and expertise with your peers and to learn from other enterprise IT professionals. TechTarget provides the infrastructure to facilitate this sharing of information. However, we cannot guarantee the accuracy or validity of the material submitted. You agree that your use of the Ask The Expert services and your reliance on any questions, answers, information or other materials received through this Web site is at your own risk.