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 From:  "Klaus Stock" <ks at stock dash consulting dot com>
 To:  m0n0wall at lists dot m0n0 dot ch
 Subject:  Re: [m0n0wall] Erratic download traffic graph report
 Date:  Wed, 13 Dec 2006 12:36:17 +0100
> Your better ask your internet provider. In a cable modem 
> system you share a segment with a number of other users, 
> so the actual bandwith you get depends on other activity 
> on your segment.  They cannot provide you a fixed bandwith 
> as with DSL.  Do the test again during low traffic period 

DSL provides you with a "guaranteed" bandwidth only up to the DSLAM ("DSL
Access Multiplexer/Module" or something like that, usually a box up to a few
100 meters away from your endpoint). A typical DSLAM provides access for a
few 100 users. The DSLAM itself is connected to the internet backbone with a
"big pipe" (often a T1 or something comparable). "Big" if you compare to the
bandwidth of your single DSL line, but "rather small" if you compare it to
the combined bandwidth of all connected DSL users.

If "your" DSLAM has a 155MBit/s connection, 11 users with a 14MBit downlink
can reach full speed simultaneously. More than 11 users, and you'll
experience the joy of a shared medium.

Fortunately, the connection to the backbone is typically with ATM, so you'll
get a guaranteed slot assignment in some finite time (unlike "good olde"
ethernet, where one user might cause "channel grabbing" and thereby block
out anybody else).

Best regards, Klaus

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