With WAN optimization, if a business user sends a large PowerPoint file to a branch office and the recipient changes just one slide, the entire file is not retransmitted back from the branch office to the user -- only the changed data.
In some ways, the Solutia example reveals how the term "WAN optimization" is a misnomer, because optimization often implies acceleration: If you optimize a sports car, it goes faster. Even though the companies that make the appliances usually talk about statistical value -- increasing performance up to 32 times, in some cases -- the products aren't actually changing the speed of the network.
Yet the compression alone is often worth the investment, which typically runs just a few thousand dollars for an appliance that optimizes a 3Mbit/sec. to 5Mbit/sec. connection. (Optimizing a 100Mbit/sec. pipeline can cost well over $10,000 for just one appliance, however.) That was the case at Activision, a well-known game publisher, which has three district offices, 13 development studios (some in countries such as Japan and Australia), several sales and marketing offices ranging in size from six to 200 people each, and a corporate office.
The issue Activision faced wasn't directly related to application performance -- although the company recently conducted its first WAN optimization test from the US to London for an Oracle 11i application. Instead, the company that made Guitar Hero 3 and Call of Duty 4 was struggling with network latency.
According to Thomas Fenady, a senior IT director, the process of developing games was hampered by some harsh realities of WAN networking. With each game build ranging in size from 4GB to 12GB each, employees in remote offices had to wait about eight hours to receive the latest files, sometimes watching movies or heading home for the day until they could start working on the latest version of the game.
"We blamed the problem on two issues," says Fenady. "One is just the speed of light, which we could do nothing about. Even over a 35Mbit/sec. or 45Mbit/sec. connection from Santa Monica to Dublin, we saw latency go from 100ms to 180-200ms to 250ms or higher. The other issue was TCP inefficiencies [where the nature of the Transmission Control Protocol causes the transfer speed to throttle down as congestion occurs]. TCP throttling makes a connection drop down slowly when you lose packets. With WAN optimization, those same game-builds now transfer in about 15 minutes instead of eight hours." The transfer times were reduced so dramatically because WAN optimization weeds out congestion and latency problems and therefore helps reduce TCP throttling.
Fenady noted that although network latency wouldn't have hampered game development (because the company would have found a work-around in order to make release dates), the optimization makes the development process more fluid and less of a waiting game. He says the big challenge with optimization -- one that separates one vendor from another -- is that it's easier to optimize a T1 or T3 connection, but a line that runs at 45Mbit/sec. or higher is more difficult to optimize. This is because the much faster networks transmit data so rapidly that it's difficult to quickly analyze which data can be compressed, which data is encrypted and which data can be de-duplicated.