It's no secret to network managers that if they want to perfect application performance, they need to be thinking about performance before the application rolls out across the local and wide-area net. Industry watchers agree.

"Distributed services and applications that operate effectively across distributed servers as well as the whole of the network can bring significant advantages to the enterprise," writes Rich Ptak, an industry analyst. "Realizing this promise requires improvements not just in management and monitoring after deployment, and most cost-effectively, in the ability to discover potential problems before the application is deployed or the network change implemented."

Recently, Ptak's research firm - Ptak, Noel & Associates - released a research paper on the topic, highlighting how Shunra specifically addresses the issues with its Shunra Virtual Enterprise 4.0 product. According to the report, the technology simulates any production network in a lab or on a workstation to show network managers how an application will perform on any given network prior to deployment.

But, the report points out, Virtual Enterprise is more than just a simple WAN emulator. It allows users to create models of their own network behavior and store data in a local repository. The product also checks to see if application performance will live up to predefined service levels, the report states.

Other vendors, such as Apposite Technologies, Network Nightmare and Candela Technologies with its LANforge product, also provide tools that emulate WAN conditions. And companies such as Compuware, Mercury Interactive, NetIQ and Opnet develop software that profiles how an application will work under existing and simulated network conditions. (For more on this, read "Perfecting apps performance".)

Regardless of the approach, this industry watcher advises network managers to test applications to better achieve optimal performance.

"Applications pushed into operational deployment without rigorous pre-testing to determine performance and operational issues in the network will only bring grief to any enterprise taking such a risk," the report reads.

Ann Bednarz is associate news editor at Network World.