help with dsl speed

[Hal Burgiss]

On Tue, Oct 16, 2007 at 03:18:10PM +0100, Steve Flynn wrote:

>     I have 7.6mg dsl here at the house . When I look at the router it say's
>     7.6mg bu when I do a speed test I get 5.5mg any ides ?
> 
> 
> Your router is reporting the sync speed to the DSLAM at the
> exchange.
> 
> Your speed test test the data transfer rate between you and the
> remote machine. That is, the entire route between you and a machine
> potentially 30+ hops away. Each one of those hops may be a link
> which cannot saturate your 7.6 meg connection as it's also
> transferring data for 25,000 other connections.

There is also protocol overhead. The line rate is raw, the speed tests
are not. The tests only show the payload portion of each tcp packet.
There is a certain amount that the laws of physics and tcp/ip have to
have to make a two way connection work (reliably), and these aren't
factored into the payload.

-- 
Hal