Hi,
The BT Speedtest can run up to 3 tests depending on what speed you get on each test.
The first test (TAP1) tests the speed between you and the Internet going across both the BT network and our network. A slow speed on the TAP1 test could mean that slow speed is caused anywhere between your PC, router, line etc. to our network and our network transit/peering links or the BT speedtester itself. However, the TAP1 test goes into our titanium queue and doesn't get rate limited on any product even if you hit your usage allowance and would normally see restrictions. That means that even if our network is really really busy and everything else is slowing down the BT speedtest should still give a normal speed for your line, so a slow speed on the BT speedtest TAP1 is almost certainly going to caused by something before you get to our network or something between the core network and tarnsit/peering links. The result of TAP2 would confirm this.
The second test (TAP2) which you are prompted to run if the TAP1 is slow enough has you log in with a 2nd username which tests the speed between you and the BT side of of 622Mbps central pipes. A slow speed on TAP1 and a fast speed on TAP2 indicates the cause is between our central pipes and our transit/peering links whereas a slow speed on both TAP1 and TAP2 rules out our side of the network.
The third test (TAP3) which you are prompted to run if TAP2 is also slow tests the speed between you and your local BT PoP. A slow speed here rules out the BT cloud between your PoP and us in London and means the cause is really down to your equipment and line or something at the exchange or exchange capacity.
Dave Tomlinson
Enterprise Architect - Network & OSS
Plusnet Technology
I am also having problems with lower than usual speed as it appears others are to.
