InformationWeek.com

Welcome Guest. | Log In| Register | Membership Benefits

January 24, 2000

Smooth Operations Depend On Smart Testing Plans
continued...page 2 of 2

Related links:

Take Your LAN For A Test Drive

And from our sister publications:

Data Communications Proxy Caches

InternetWeek HP Spin-off Debuts Internet-Size Test System

Send Us Your Feedback

In the past, Breit relied on mathematical tools to project capacity requirements. Statistical tools use mathematical averages to determine how many users an application can accommodate and still deliver adequate performance. But these tools were insufficient, he says, because they were unable to accurately estimate the scalability of an application.

"Scaling is very difficult to predict in a production environment," Breit says. "An application may perform well with 89 users, but when the 90th user jumps on, response times could slow to a crawl." At best, statistical tools were 60% to 70% accurate; the Ganymede tool is more than 90% accurate, he says.

Breit acknowledges the tool has some flaws. For instance, although the First Data group has automated many processes associated with using the Ganymede software, Chariot still requires quite a bit of manual work to load and analyze network trace data. That makes the tool far from simple to use for companies that don't have a lot of experience with Chariot.

Nevertheless, Breit says, there's a great payoff: Chariot helped make the company's PeopleSoft deployment a success. "In the six months we've had the application up and running, we've never received a single complaint about PeopleSoft's performance," Breit says.

Chariot is designed to help companies not only with their deployment of new applications, but any time they need to make changes, including adding new network interface cards, says Kim Shorb, product manager at Chariot. For instance, if a company is upgrading from a 10-Mbps network to a 100-Mbps network, it could use Chariot to see how much the network's application performance will improve.

Some users say one of the more compelling uses for Chariot is assisting with the deployment of voice over IP. Chariot supplies IT professionals with a mechanism to determine if their systems can handle voice over IP and, if they can, what the performance impact will be on existing business applications. "Chariot's value in capacity planning for the purpose of convergence is tremendous, because it is important to understand how the network behaves before you deploy voice over IP," says David Larson, technical marketing manager for 3Com Corp.'s competitive analysis of enterprise switching solutions.

Larson uses the Ganymede product in 3Com's performance testing of its high-end switching products against competitors' switches. Larson's goal is to find out how many users 3Com's switches can handle and still deliver application data at acceptable speeds when voice over IP is introduced on the network, compared with competitors' abilities to handle those loads. He compares these figures against network performance when voice over IP isn't a factor.

Larson says he's been using the product weekly for almost three years to get highly detailed session performance reports, but the latest version of Chariot added support for a number of multimedia protocols. This includes the Real Time Transport Protocol, a component of the H.323 specification; Chariot can now track one-way jitter, an important measure of quality in voice-over-IP traffic.

Larson says Chariot's capabilities are useful in real-world voice-over-IP deployments. "If you want to set up a network with a number of different application priorities and bandwidth guarantees, Chariot gives you a way to see the differentiation of service for individual applications," he says. This is critical when dealing with voice-over-IP traffic, which is time sensitive.

Because the application uses the real protocol stack and can track performance from one end point to another, Larson says, Chariot's reports are highly accurate. Chariot can support testing for the following protocols: TCP/IP, User Datagram Protocol, Systems Network Architecture/Advanced Program to Program Communication, Internetwork Packet Exchange, and Sequenced Packet Exchange.

Ganymede licenses the Chariot console and the end-point agents separately. Chariot console licenses are priced from $14,000, which includes licenses for an unlimited number of end-point agents.

return to page 1