10 ways to improve network performance

When your car starts to get sluggish you pop the bonnet and check the individual components underneath.

So why is it that when our networks start to run slow the components are often the last thing considered? We take the blame off the network itself by giving you 10 ways you can improve network performance.

When most people's idea of a network was a workgroup LAN, it either worked or it didn't. If it didn't, the most likely causes were a crashed server or a disconnected co-axial cable. Today's enterprise networks are far more complex, with more potential sources of failure or degradation, and a wide variety of different traffic types competing for scarce resources. One effect of this complexity is that there are many different components that can be managed, supplemented, replaced, or just plain tweaked in order to get the performance levels required. We trawled the industry and have come up with 10 ways you can improve network performance without having to replace or upgrade your infrastructure.

1. Understand your network
Without having an understanding of what's actually happening on your network, you are likely to fail at any attempt to address performance issues. Peter Prichard, marketing director Asia-Pacific at Compuware, says people tend to blame the network for poor performance, but the PCs and servers can also be the cause.

"The first thing to do is make sure the network really is the problem," Prichard says. "Even if it's not the network, IT spends a lot of time proving it's not." Tools such as Compuware's Vantage suite can isolate problems such as a slow client, excessive latency on a WAN link, or poorly written SQL on a back end server. An application might be developed on a LAN and then deployed over a WAN with disappointing results due to an excessive number of database calls. This sort of analysis may reveal things you didn't know about your network, such as a 1.5Mbps WAN link when you're paying for 2Mbps, says Peter Owen, territory manager at Packeteer. Collecting the right information also lets you take an active stance, identifying and dealing with problems before they impact on users.

Many people will blindly add bandwidth in an attempt to solve a perceived problem -- this tends to be one of the biggest mistakes people make, Prichard says. "You've got to have facts -- application-based facts," he says.

David Gibb, technical consultant with Vanco Australasia agrees. He says that what may dramatically improve performance in one environment could hinder performance in another.

Scott Atkinson, managed LAN services practice leader at Netforce, points out, there are a variety of free, cheap, and expensive tools that singly or in combination can show what's happening and why. MRTG (Multi Router Traffic Grapher), a free utility from http://people.ee.ethz.ch/~oetiker/webtools/mrtg/, is one that can help you gain an understanding of your network.

A network analyser itself will only show the aggregate traffic, and won't deliver the information you need. Prichard says to "start with the premise that the application is king", rather than checking individual aspects of the infrastructure.

Lorenzo Modesto, general manager at Bulletproof Networks, says this monitoring should be accompanied by alerting. Once the monitor is tuned to avoid false positives, an appropriate person should be automatically alerted when an unusual event occurs. "SMS is absolutely perfect for that," he says.

When it comes to things such as radio frequency, monitoring is important for good wireless LAN performance, says Mark Hayes, manager of consulting and solutions at CSC. "The RF environment is not static," he says. According to Hayes, a WLAN coming online on a close neighbour's premises can affect the performance of your network.