Try before you buy -- it's an adage most wide area network (WAN) managers already know when vetting applications to deploy over the WAN, yet canned vendor demos or sanitized lab tests rarely reveal how apps run across countries and continents. The growing complexity of WAN topologies is only muddying the picture, but more sophisticated WAN emulators can give real insight into performance.
"With more applications running on the WAN and more WAN topology options, WAN emulation becomes more important than has it been," said Ron Westfall, a research director at Current Analysis. "It's a cost-effective, requisite item because there's just no way [of] avoiding these increasing bandwidth demands and increased [network] complexity."
WAN emulators in complex topologies
Network engineers at Talon Data Systems, a Hollywood-based systems integrator and manufacturer of high-end post-production equipment for the media and entertainment industry, use WAN emulators on a weekly if not daily basis, according to Ken Spickler, director of systems engineering.
As engineers test out Talon's proprietary software -- designed for high-speed data transfers across WANs -- they replicate how it would perform between London and Los Angeles, fine-tuned to their customers' baseline performance specs, Spickler said.
"It's something we're using constantly," he said. "Before, we were kind of guessing.… [WAN emulation] was something we knew we needed to have in the lab."
Spickler started with a low-end WAN emulator, Linktropy, from Apposite Technologies, which served Talon's purposes at first. But as Talon's customers started using more complex WANs with multiple types of links and multiple data centers, Spickler realized that he needed a more robust WAN emulator that could simulate multiple WAN links. He recently upgraded to Netropy, Apposite's newest WAN emulator.
"It allows us to more closely simulate what our customers have in their environments," he said. "They might have [our product running] in multiple branch facilities, and we can simulate that in our lab."
The value of using WAN emulators extends beyond deploying a new application and is no longer limited to very large enterprises or service providers, according to Bojan Simic, founder and principal analyst of TRAC Research.
Enterprises that are consolidating data centers or completing larger centralization projects, such as virtual desktops, don't have to guess the impact on remote users. By considering bandwidth, latency and packet loss, a sophisticated WAN emulator can simulate the experience within a 4% to 5% margin of error, Simic said.
We're seeing the problems the largest companies have now reaching the medium-sized companies and even the small companies -- they need to simulate complex network topologies.
D.C. Palter PresidentApposite Technologies
"Even for some large organizations that don't have a lot of changes [planned] … it's still very useful if they think about not new applications but new ways to manage IT," he said. "Cloud [computing] is a good example. Having that visibility into how you use these resources and how [people] are using the WAN helps organizations find out what's the best fit for moving to the cloud."
The cost of high-performance WAN emulators
Price has been a barrier for WAN emulator adoption for smaller enterprises because appliances from higher-end vendors such as Shunra Software and Anue Systems can cost tens of thousands of dollars, according to Westfall and Simic. Because their larger enterprise and service provider customers can afford them, those WAN emulators are unlikely to come down in price, Simic said.
Apposite Technologies cracked open that door for smaller enterprises in 2006 with its Linktropy appliance, offering a lower-end option for companies with frugal IT departments, both analysts said.
Linktropy appliances start at $1,975 for the Mini2 model and go up to $20,000 for the high-end 7500 PRO model. Its newest line costs between $8,000 and $35,000, depending on model and bandwidth. But the trade-off has been that Apposite's WAN emulators weren't as powerful or robust as those of its competitors, which market to large enterprises and service providers.
"More and more, we're seeing the problems the largest companies have now reaching the medium-sized companies and even the small companies -- they need to simulate complex network topologies," said D.C. Palter, president of Apposite. "They need to simulate a network where they have some of their applications going to a data center, some of their applications going to a cloud service provider, and some of their data being sent to a remote backup site."
Apposite's newest line of devices -- announced this week -- simulate 15 simultaneous links for each engine on the appliance. Maximum speeds range from 1 Gbps to 10 Gbps.
- The N60 runs one engine with WAN emulation for 15 links. Depending on bandwidth, prices range from $8,000 to $15,000.
- The midsized model, the N80, runs four simultaneous emulation engines, simulating up to 60 links. Prices range from $12,500 to $22,500, depending on bandwidth.
- The highest-end model, the Netropy 10G, can run two 10-gig engines and one 1-gig engine simultaneously, each supporting 15 simultaneous links. It costs $35,000.
"The pricing [on competing WAN emulators] was ridiculous," said one enterprise architect and Apposite customer at a manufacturer on the East Coast, declining to have his name or employer published. "It was hundreds of thousands of dollars for the [other] devices we were looking at."
The enterprise architect has used Apposite's lower-end Linktropy 7500 PRO for the past two years, and he doesn't anticipate upgrading anytime soon. The WAN emulator helped him test the performance of a VoIP system that he planned to deploy across his company's 80 global locations. With it, he discovered latency that would bog down some sites. Using what he and his team had learned from the WAN emulator, they engineered the solution differently for those sites, he said.
"We have what was their biggest box when we bought it," he said. "Unless we have a need for more simultaneous proof-of-concept work within our lab, we're good with the four interfaces. But if we were to exceed that [capacity], [the newer model] would be the first thing we look at."
Let us know what you think about the story; email: Jessica Scarpati, News Writer