Your computer slows down, gets old so you replace it with a new one and wow … it is so much faster. What about your network switch if you have a home or business network? If you find your computer is fast but copying files to other computers or surfing the web is slow then it may be your network. If you use a server and find programs timing out, give you errors, or plain and simple are just not working properly, perhaps check your local area network as it may be your bottleneck.

If your network switch is more than 6-7 years old then chances are it does not support newer switching technologies or all that dust that has built up in it over the years has overheated it to the point of being almost burned out. If you are unsure if your network is the issue or you suspect you may have a bad cable or connection you can try a local area network test to see what your actual data transmission speeds are. Download Lan Speed Test to see for yourself. http://download.cnet.com/LAN-Speed-Test/3000-2085_4-10908738.html

I was having issues with Outlook doing odd stuff connecting to our exchange server. When I opened Access databases on our server sometimes they would seem to freeze up but after a minute they would finally open up … very slowly. We had a 10Mbps extreme Internet connection yet the fastest we could get on downloads was barely 512kb. When I connected my laptop direct to a neighbors cheap internet I got the same download speed and all tests showed our Internet was fine. Even printing to our lan printers took a quite a while to queue up. The other thing that got me was the task manager network utilization never crept over 1% on the server or any of the PC’s even when copying large files that would claim to take hours and hours, the network utilization was non-existing. I had a serious bottleneck somewhere.

I ran the Lan speed test and it showed local speeds of barely .9 to 1.5Mbps speeds. LOCAL speed I am talking here on a 100Mbps switch no less and with no traffic on the lan ??!?! I swapped out our 7 year old DLINK 16 port switch with another DLINk 24 port 10/100 Mbps switch that we pulled from a client office. (They upgraded to POE1000Mbps network fyi) I re-ran my tests and this time it came back a dismal .45 to .81Mbps on the lan. So this used switch was even worse than my own switch. What the heck?

I connected my computer to the server direct through our 3 year old 4 port Firewall router and got speeds of 4 to 12Mbps. That was better but still nowhere near what I expected for a 100Mbps lan with no traffic on it beside my lone computer late in the evening after hours.

I checked the drivers on my local computers. I am running Windows 7 and verified my NIC drivers and lan and connection settings were good. They were. I tried different computers, Windows XP Pro, Wndows 2008 server, Windows 2003 server. All shared the same results and the same patterns when tested on the two switches and the Router. I broke down and bought a brand new 100/1000Mbit 24 port + 2 GB port network switch from TrendNet and installed it.

I ran the same tests on the 100Mbit ports and got speeds of 81-93Mbit. I tested through the two gigabit ports and got speeds in the 512-790mbit speeds. It blew me away. I could copy a 2GB file in less than a minute that the day before would take half the night. My errors opening programs ceased immediately. My internet surfing speed quadrupled at least.

I tossed the two old switches out so they are never used as they are defective now after these many years of use. Consider the new 24 port switch cost only $100. It is time for me to assess the switches at client offices and make sure that they too are replaced in 2011 so they keep up with the new servers and workstations we are updating at the same time. We have replaced a few switches but now I need to review all my clients and see what they are using. This is especially critical of offices complaining of slow networks or software errors. The switch may be the cheapest and easiest thing to replace and certainly with a new switch you can rule it out as a problem and then focus on network wiring or true software or computer issues.

Keep in mind this is a purely un-scientific or methodical approach to solving this issue but I find my gut often is right when I suspect a problem. I also find ths approach more commonly used because most people do not posess $3000 fluke network testing equipment or have a deep knowledge of ethernet protocols and benchmark testing. Work with what you have and what you know and go from there.

In the process of testing my switches I also discovered that I had one bad network cable in the wall and when it was used it had a 90% packet loss. It worked, but was extremely slow. So I covered that plug up and will use the other outlets. Maybe that is a topic for some other post like “Why do good cables go bad ?”

Cheers and safe surfing over the holidays.