connections, the upload / download speed are not related.
What they do, is assign a particular frequency domain for uploading and another frequency domain for downloading.
Hence, whenever you download and upload simultaneously ... the upload speed does not affect your download at all, unlike in Dial ups
Due to the assumption that a normal user always downloads more than he uploads, hence for an ADSL connection, the download frequency domain will ALWAYS be higher than the upload frequency domain.
Mostly, in the ratio of 1:2
However, I have run tests, and on my 256 Kbps Home plan, I have uploaded at 12 kBps ... which adds up to 96 kbps ...
So, with a 512 kbps plan, you should probably get around 24 kBps ... ie 192 kbps ...
And, for SDSL ( Symmetric DSL ), I dont think the ratio is 50:50 ... it is 100:100
So, if you have a 256kbps plan, you can upload / download both at 256 kbps simultaneously ...
For more very easy to understand 'gyan' on DSL, head to :