Special Delivery: Fast WANs and App AccelerationBy Paula Musich | Print
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Technology executives are centralizing data while their employees are dispersing. They're all waiting for the WAN to quickly deliver hot applications to mobile workers anxious for performance, and vendors are racing to deliver.
Technology executives are centralizing data while their employees are dispersing far and wide. They're all waiting anxiously for the WAN to deliver hot applicationsfastto mobile workers hankering for performance.
Technology managers and vendors are racing to oblige. This perfect storm of needsincluding more mobile workers, the Webification of software, speedier networks and office consolidationis driving the rapid growth of application acceleration technologies to the point where they are becoming enterprise mainstays just as switches and routers are today.
As those technologies, delivered today mostly as network appliances, become strategic for enterprises, Juniper Networks is one vendor capitalizing on the trend. On Oct. 16, Juniper will introduce a new high-end appliance and operating system update aimed at enterprises looking to increase their deployments from a dozen to hundreds of locations while ensuring high availability of the devices.
Juniper's launch of the new WXC590, which can support 140 locations over a single 45M bps DS-3 line or 420 locations over a 155M bps OC-3 connection when three are stacked together, coincides with the launch of another new high-end appliance from upstart rival Silver Peak Systems.
Silver Peak will introduce its NX8500 appliance, capable of supporting up to 500M-bps data rates for replicating data between data centers in business continuity applications (see related story, Page 24).
Technology executives and analysts say what's driving the rapid acceptance of these technologieswhich are divided between ADCs (application delivery controllers) that sit in front of Web servers and WOCs (WAN optimization controllers) that work in pairs between a central site and each remote branch officecan be attributed to many factors, but one sticks out: Information workers typically operate away from the corporate LAN.
Companies are removing equipment such as file and print servers from remote branch offices and centralizing them in a data center to reduce costs and improve manageability and security. This also helps to ensure that backups actually happena necessity for compliance with regulations such as the Sarbanes-Oxley Act.
The problem: Most applications are poorly designed for operating over lower-bandwidth, higher-latency WAN links. In addition, backing up large volumes of data over WANs running TCP/IP is not practical without acceleration techniques.
Increasing the capacity of WAN linksthrowing bandwidth at the problemdoesn't help, since the issue is latency, which can increase with distance.
Executives at one large enterprise said the company began evaluating acceleration technologies more than three years ago, when sensitive customer and employee data theft issues began dominating the headlines.
"It was perfect timing that this technology we had been playing with was right at the forefront of allowing us to do backups over the network without having to buy a very expensive and recurring [charge] WAN upgrade," said a large Riverbed Technology customer, who asked not to be identified.
"The problem we solved was [the need for] more tape backup. We can do backup to a central data warehouse over the network without buying more [WAN] capacity." The customer plans to deploy hundreds of Riverbed's Steelhead WAN optimization appliances.
That enterprise found out the hard way that throwing bandwidth at the problem doesn't work. A Steelhead appliance in one location was moved elsewhere, and the company replaced its 1.544M-bps T-1 link with a 44M bps T-3 link.
"It's a 28-times-bigger pipe, but the users complained it was slower [without the Steelhead appliance]. It was a latency problem, not a bandwidth problem," said the user.
In moving file and print servers out of remote branch offices, other enterprises are encountering latency issues created by the chattiness of legacy protocols such as Microsoft's CIFS (Common Internet File System) and MAPI (Messaging API).
Applications such as Microsoft's Word, PowerPoint, Excel and Exchange using CIFS and MAPI break up the response to client requests for file access into smaller chunks that are sent sequentially.
The client acknowledges each received chunk, and the next one is not sent until that acknowledgment is received by the server. So a simple action such as dragging a file from a remote file share to a local desktop generates as many as 3,000 or 4,000 client/server interactions.
Analysts at NetForecast conducted a study earlier this year of application performance response times across varying distances for CIFS, MAPI, Web and SNA applications. The study found that CIFS and MAPI performance "drops precipitously with even small distance increases from the server," author Peter Sevcik at NetForecast, in Charlottesville, Va., said in the report.
"With servers centralized in New York, performance for both application types would be poor for users in Chicago and utterly unacceptable for users on the West Coast. Without ameliorating steps, stretching user-to-server distance for CIFS- and/or MAP-based applications plots a sure course to an application performance shipwreck."
But the problem is not limited to Microsoft applications. Web applications in the study fared well at distances of up to 2,000 miles, but then response times dropped precipitously, and by 3,000 miles were considered to be in the poor range.
Web-based HTTP applications also suffer from chatty protocols and redundant transmissions.
"A browser will do individual fetches to get all the icons on your screen. If there are big objects, a fetch might take two or three round trips. If you refresh the screen and only one thing has changed, you still download the whole screen," said Joe Skorupa, an analyst with Gartner, in Stamford, Conn.
WOCs solve those problems and boost application response time over WAN links using a variety of techniques. The most common grouping of techniques includes sequence caching, compression, protocol spoofing, TCP optimization, QOS (quality of service) enforcement and encrypted tunnels.
Their counterparts in the data centerapplication delivery controllersaddress more server-based performance issues by offloading from the server functions such as load balancing, TCP connection management, SSL (Secure Sockets Layer) encryption and Web application firewalls. They also execute compression and caching.
Next Page: Consolidation crush.
"Both categories are solving different aspects of the same problem: how to deliver highly available, consistent, low-latency transaction performance," Skorupa said. "WOCs go further and do it for remote file access, remote mail access and browser-based applications."
Meanwhile, natural disasters such as Hurricane Katrina are driving awareness that distributed data, even if it is centrally managed, is exposed to greater risk of loss and business disruption.
"In Florida, when storms were crisscrossing the state, it raised awareness that I needed something high speed connected elsewhere that wouldn't be affected by a storm," said Harold Hamm, vice president of IT at Reynolds, Smith and Hills, in Jacksonville, Fla.
"Today all our offices have servers in them, but in the next three to five years, I'll be centralizing all that data again. I can host it in a hot site that's got power redundancy, generators, multiple links to the Internetall those things so that data is in a very secure, recoverable environment," said Hamm, a Cisco Wide Area Application Services user.
At the same time enterprises are moving to centralize servers and data centers, they are also dispersing users who access data farther and farther away from those centralized locations.
A recent study conducted by Nemertes Research found that 87 percent of employees work away from the company headquarters. They could be in a branch office, home office, on the road or anywhere other than a main corporate campus, according to author Andreas Antonopoulos in New York.
"The geographically concentrated company is becoming a thing of the past. Enterprises are consolidating data but dispersing employees, and the WAN is in the middle of a tug of war," Antonopoulos said.
At the same time, some 55 percent of companies surveyed said they have had to consolidate data centers within the past 12 months, and another 57 percent planned to do so within the next 12 months, according to survey respondents from midsize and large enterprises.
To date, most deployments have been tactical solutions to specific pain points for a handful of remote offices.
"What we've seen to date has been a knee-jerk reaction," said analyst Robert Whiteley at Forrester Research, in Cambridge, Mass.
"As an organization, I may have just rolled out a new version of SAP and it's not working, or maybe I just consolidated branch offices and productivity is declining. Or I'm trying to put business continuity in place and that requires regular backups in the branch office and that's not consistent. Any one of those could be my poster child."
In those cases, the appliances have been easy to justify as a cost-avoidance mechanism for any location that would have required a WAN link upgrade to solve the problem.
"To jump from a T-1 to a T-3 is a significant amount of recurring cost. When an office gets into the 10- or 12-user range, you can justify the investment," said Juniper WXC user Robert Bell, director of IT at architectural and engineering company Ghafari Associates, in Dearborn, Mich.
So just where is the market today? Gartner put total user spending for both WOCs and ADCs at $1.45 billion last year, with ADCs leading the way at $875 million.
This year, Gartner predicts overall end-user spending will grow 27.6 percent, to $1.85 billion. But Gartner predicts that next year will be the banner year, when end-user spending reaches $2.9 billiona 57 percent growth spurt. That makes it "poised to go mainstream," Skorupa said.
In the meantime, evidence is building that the early adopters are moving to more widespread use of the technologies.
"Now we are seeing deployments in the hundreds of sites. A significant amount of the business we closed in the last 120 days had initial orders north of $100,000," said Mike Banic, senior director of product marketing at Juniper, in Sunnyvale, Calif.
Liz Claiborne, another Riverbed customer, expects to have more than 100 Steelhead appliances installed within the next two years. "For every new office that comes up, we plan to have those devices there," said Bob Czukkermann, supervisor of LAN administration at Liz Claiborne, in North Bergen, N.J.
Now every Liz Claiborne office in North America and Asia has a Steelhead appliance, as does a data center in Europe. Company officials said it would be nice to be able to install the appliances in its 400-plus stores, but it is not yet cost effective to do that.
"That is something we'd like to do and something we are investigating," said Czukkermann, who added that Liz Claiborne also would like to see software-based client implementations. "This is how much of an effect we've seen," he said.
Apparently, investors also see the application acceleration market going places, too. Last month, Riverbed, arguably the market leader, saw one of the more exciting tech IPOs (initial public offerings) since the market went bust.
The company upped its initial asking price from a range of $7 to $8.50 up to $9.75 per share before the IPO. Investors bid up the price right off the bat to $14.30, giving the new public company a market capitalization of $627 million.
What could help fuel growth is the emergence of what Gartner calls the soft WOC, which is either "a substantial enhancement of the client-based software in an application delivery controller or a pure software client-based instantiation of a WOC," said Skorupa. "It runs in a laptop, desktop or PDA and provides a subset of functions such as protocol spoofing, advanced compression, etc."
The exuberance will bring in larger players with deep pockets to further the consolidation already under way. "On the supply side we'll get down to the top five vendors in the next six months," predicted Forrester's Whiteley.
As application acceleration technologies become a significant part of the network or server infrastructure, users will be challenged to learn how to manage larger-scale deployments. One of the bigger issues is learning how to perform capacity planning, said the anonymous Riverbed user.
"When you have these accelerators in place and you're running at 100 percent utilization, it means the accelerators are doing a very good job. In the past at 100 percent utilization, TCP threw a fit and misbehaved and resulted in applications slowing down. So capacity planning becomes more difficult to do, and network modeling becomes more difficult to do," he said.
But whatever challenges acceleration technology presents, few if any events could turn back the tide once end users see the performance gains it affords.
"People are so accustomed to this speed now, you can't take it away," said Ghafari's Bell. "Once you put them in, you can't take it out."
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