On Friday 03 November 2006 00:16, Ronald Wiplinger wrote:
How can I test the bandwidth of my ADSL line?
Problem: I should have an ADSL line with 12Mb/sec download and 1Mb/sec upload speed.
The MRTG graphic of my ISP shows only 3Mb/sec. I complaint! Than the ISP makes a test and shows me 13.8 MB/sec
I wonder how they made the test? I suspect that they collect the data for the MRTG graphic on their router and that the test is only saying that they send out so many bytes, what does not mean that I got the bytes!!!
After their test I started immediately to download from different sites to download big files, like Suse 10.2 beta and got a total speed of again 3Mb/sec.
Obviously our testing is wrong! How can we really measure the bandwidth???
Are you sure everyone has Mega-BITS and Mega-BYTES in order for all the speeds discussed above? Comm is typically measures in Bits Per Second. A fairly good rule of thumb for TCP/IP is to divide the bits per second by 10 to get bytes per second. So, if you have a 100 MegaBIT ethernet port the max throughput on that connection would be in the neighborhood of 10 MegaBYTES per second. If that is how you connect to your router, then it is unlikely you will see 13+ MegaBYTES/sec. So, it may be that they're discussing an internal test. Also note that throughput of your end of the path is limited to the slowest bandwidth of any segment in the path. The internet connection in my neighborhood is a fiber optic line split between 8 houses. We're "guaranteed" 1MBYTE/second download, but since everyone is not using the network most of the time I usually find the download speed much faster than that (Record speed 3.8MBYTE/sec).