Be prepared.

Rely on WDM for disaster recovery.

If any company understands the value of instantaneous, complete data backups, it's EMC Corp. In becoming the world's leader in the growing market for intelligent enterprise storage systems, software, and services, EMC has seen firsthand how companies of every industry are utilizing leading-edge networking technologies to protect their data and investments in time, work, and money.

In 1998, EMC implemented ADVA's optical channel multiplexer (OCM) solution to link its two Hopkinton, Mass., facilities. Without incurring the costs or complexities of running additional optical-fiber strands between the two sites, EMC has realized the security of a comprehensive disaster-recovery strategy. Not only does the wavelength division multiplexing (WDM) system support asynchronous transfer mode (ATM), Gigabit Ethernet, and other high-speed, LAN-application traffic between the two sites, EMC's product-development and other mission-critical data is continuously mirrored. And there is no impact to network performance; all protocols run at their native speeds.

FORESEEING THE UNFORESEEABLE 

The primary motivation behind EMC's decision to implement a system for sophisticated data backups was disaster recovery. Paul DiVittorio is Unix support manager for EMC Corp. The underlying responsibility to all of his jobs in that role is making certain that the company's 11,200 employees worldwide have immediate, easy access to customer, product, and corporate data 24 hours a day, seven days a week. If a truck wrecks on the EMC Corp. campus in Massachusetts, taking out a key generator and telephone pole in an instant, DiVittorio is not absolved of that responsibility.

Before solutions such as EMC Symmetrix Enterprise Storage systems and software emerged, enterprise disaster-recovery strategies worked like this: A company backed up its mainframes and other data systems on tape, loaded the tapes onto trucks, and delivered them to a separate, presumably safe remote facility. In the event of a calamity back at the main data center, trucks were sent back out to retrieve the latest batch of tapes. It was a far-from-perfect plan for multiple reasons. The recovered data was only as up-to-date as the most recent truck roll to the remote facility; the process itself was nightmarishly time-consuming. To have hopes of being back up and running on the second business day after a total failure was to be optimistic.

Is it any wonder--what with millions of dollars of revenue per hour at stake in the case of Fortune 500 enterprises--that the clamor for a better way grew deafening?

WDM ARRIVES

Large banking and financial institutions in metropolitan cities were the first, in the early 1990s, to deploy private optical-fiber-based networks between facilities as a high-bandwidth solution for disaster recovery, as well as other business applications (storing data, clustering high-speed computers for parallel processing, handling the facility moves associated with mergers and acquisitions, implementing multimedia business tools, etc.). But networks once thought to provide ultimate scalability are running out of capacity. As Internet Protocol communications grow more prevalent, data traffic is beginning to exceed voice traffic in volume. Video applications have proliferated. Networks are buckling under the weight of heightened, heterogeneous demands on available bandwidth.

WDM emerged to enable improved bandwidth performance over dark fiber. WDM multiplies the capacity of optical-fiber strands, creating "virtual channels." Incoming application traffic is converted to specific wavelengths and multiplexed. Multiple channels are transmitted over the same fibers. There is no performance degradation or specific protocol requirements because light waves of different lengths do not interfere with one another during transmission and are converted back to their original formats at output.

WDM's arrival has been a boon for enterprises. Across distances up to 50 kilometers, enterprises can simultaneously utilize ATM, coupling link, enterprise system connectivity (ESCON), Ethernet, Fast Ethernet, fiber distributed data interface (FDDI), Fibre Channel, FICON, Gigabit Ethernet, SONET, EMC symmetrix remote data facility (EMC SRDF), sysplex timer, and other high-speed, proprietary applications without impact on network performance.

EMC'S NEED

The company's goal was to enhance connectivity between two of its Massachusetts facilities linked by 24 optical-fiber strands. The fiber backbone running between the two sites was exhausted with ATM, Fast Ethernet, and Gigabit Ethernet applications. EMC sought a solution that would make use of the existing infrastructure and prove to be:

* flexible, supporting SRDF and ESCON traffic, in addition to the in-service applications;

* upgradeable, capable of supporting additional, faster protocols as the company's networking needs evolved; and

* protocol-transparent, not requiring the utility to expend resources to physically replace modules or configure data-rate changes.

"We considered leasing additional fibers," says DiVittorio. "But that's very expensive, and it takes a long time to get permits. We might have been looking at an 18-month turnaround. That wasn't a realistic possibility."

EMC turned to WDM. No additional fiber strands would have to be installed--only an active wavelength division multiplexing system at each facility.

THE RIGHT CHOICE

After settling on a technology, EMC began the process of identifying the right system for its particular situation. Price, of course, was a significant consideration, but it wasn't the only one. Capacity growth for future needs directed EMC to eight- and 16-channel WDM systems. The company required a solution appropriate for the realities of its facilities and workforce and identified it in ADVA's OCM 8 and OCM 16 solutions, sold as the OM/9000 Model 25-8 and Model 25-16 by INRANGE Technologies.

EMC had evaluated a variety of vendor solutions. Most were too big, requiring more of the valuable real estate in the two data centers than EMC was willing to commit. The ADVA solutions EMC purchased have a 19-inch, rackmount, hot-swappable, modular architecture with more reasonable power requirements and environmental tolerances than the other systems the company investigated.

And of no small benefit was the ADVA solution's plug-and-play installation capabilities and low-maintenance nature. EMC's network-support staff in Massachusetts numbers 16 people. It supports 25 terabytes worth of data and 2,500 systems.

"For my team, there was very minimal time involved in bringing up the WDM system," DiVittorio says. "We unboxed it, connected the fiber cables, and turned it on. That was the extent of it. Given the range of protocols and applications supported, we were very impressed with the simplicity of installation. Other systems require configuration of protocol-specific channels and intensive software setup. Also, the ADVA solution's SNMP software-management module was easy to configure, and it has enabled us to manage and monitor the system via our existing software-management platform."

And, in making its selection, EMC sought a provider experienced in satisfying enterprise needs for high-bandwidth optical networking solutions. It found two. ADVA, founded in 1994, has an installed base of more than 150 service-provider and private-enterprise customers. INRANGE Technologies, with personnel in 50 countries, is an industry leader in sales, service, and technical support of data-center-networking channel-extension products.

FINAL ANALYSIS

EMC has multiplied its available bandwidth by up to 16 times. "Now, as we grow and our bandwidth needs grow, our network is positioned to gracefully handle the additional load," DiVittorio says.

Using its own EMC Symmetrix Enterprise Storage systems, EMC's mission-critical data is mirrored at each Massachusetts site. Data is backed up continuously. In the event of catastrophic failure at either site, users would never know the difference--their requests on the network would automatically and seamlessly fail over to the in-service data center. And because of the high network availability created by the ADVA solution, the ATM, Fast Ethernet, and Gigabit Ethernet application traffic is never impacted and may also share the same growth over WDM.

"Having a comprehensive strategy for disaster recovery and the tools to make it work is a great measure of security for both EMC and me personally," DiVittorio says. "We've had the system up and running for more than a year now, and, fortunately, we've never had a disaster that caused us to fail over. But you never know. That's the whole point, and we absolutely cannot afford to be unprepared."

Circle 278 for more information from ADVA Optical Networking, Inc.