Companies turn to capacity planning to find bandwidth bottlenecks

Computerworld - Global oil company ConocoPhillips was all set to roll out SAP AG's Business Information Warehouse for users in Perth, Australia, but the early reports on the project weren't good. "This was a high-profile project, and some application owners were telling me that the network had a 15-second delay," says Dave Strobel, operations supervisor in ConocoPhillips' global information systems network operations group.

The application resided on servers in Bartlesville, Okla., where Strobel works, with a 2Mbit/sec. E1 connection to Perth. There was a demand for more bandwidth. But a new international circuit would have entailed a significant multiyear expense and required 60 workdays to set up, meaning it wouldn't be ready by the go-live date.

So Strobel handed the problem off to Bethesda, Md.-based Opnet Technologies Inc., which had been trying to sell him its network capacity planning software. Opnet did some packet captures and ran tests that took a total of 1,400 seconds to execute, far longer than they should have.

Opnet took the test results and modeled what would happen if the bandwidth to Australia was increased from 2Mbit/sec. to 20Mbit/sec. That cut only 0.38 seconds off the 1,400 seconds. Next, it modeled what would happen if the capacity was cut to 256Kbit/sec.; that added only 13 seconds to the transaction, a loss of less than 1%. "Bandwidth clearly wasn't the issue," says Strobel.

"When we looked at that data and analyzed it with Opnet, we found that very little of it was network delay," he says. "But we found a substantial amount of the delay was on the servers in Bartlesville."

The application team solved the problem with the servers, Conoco-Phillips didn't have to spend money on a multiyear contract for a multimegabit international pipe, and Opnet made the sale.

Capacity planning—the process of predicting IT needs, often with the help of software—has long been regarded as something of a black art. The feeling was that only a specialist with a degree in statistics could do it, and even then, the results were questionable.

But capacity planning tools are becoming easier to use, and companies are finding that they can help solve a wide range of long- and short-term bottlenecks. Tools now autodiscover network devices and connections, for instance. And pull-down menus allow for quicker configuring of models. Since those features shorten the time it takes to run scenarios and provide faster answers, the tools are being used to solve current problems, not just to estimate the upgrades that need to be included in next year's budget. As a result, the software is no longer shelfware.