Please do not use this tool unless asked to do so by 123vISP Support, as we need to setup an IP monitor on our server to catch your data; otherwise the test is useless and will not work.

Please download the Iperf software (2.26mb) for Windows from: http://ssl128bit.net/downloads/tools/kperf_setup.exe

The Iperf tool (K-perf/J-Perf) requires Java; you can get Java from http://www.java.com/

:: What is it? ::
Iperf monitors IP packets between two nodes and measures the results. We run Iperf in 'server' mode on our network, and you run the client on your computer.
Note:If you are using NAT you will need to port forward ("Virtual Server") TCP port 5001 from your ADSL router to the machine on your LAN you're running iperf on as our LNS needs to connect back to that port to test your download speed. You also need to make sure your firewall allows incoming connections to tcp port 5001 on the machine you run iperf on. If you can't do this then we can still test the upload speed of your connection, so don't worry too much.

:: Running the test ::
Note: To ensure accurate readings please disconnect all other equipment (servers, computers, VoIP systems, IP cameras, etc.) that may otherwise attract or send IP packets; once the test is complete you may reconnect.
Start Iperf by click Start > All Programs > Kperf > J-Perf Measurement Tool
Type iperf.iseu.co.uk into the "Server" field
Select "Dual" as the "Testmode", as this will attempt to test both download and upload speeds.
Click "Run" to start the test. We recomment running several tests at different times of the day.

Send the tests to us here at 123vISP Support so that we can dig out the logs from the server and compare the results; please include the exact time and date of the test.
(Windows may generate a security alert asking for your permission to 'unblock' this application; you'll need to 'unblock' it to perform the test.)

:: What next? ::
We will reply to your tests as soon as possible. We may be able to solve things from our side, offer a solution to implement on your side, or we may even request further information.