Mailinglist Archive: opensuse-edu (225 mails)

< Previous Next >
Re: [suse-linux-uk-schools] ADSL speeds into school
  • From: David Bowles <dbowles@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>
  • Date: Tue, 6 May 2003 03:21:09 +0000 (UTC)
  • Message-id: <4828548401.20030506042042@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>
...err, I didn't realise this. Is this specification practice
documented anywhere on the web?

> Contention are frequently misunderstood. 5:1 actually means something
> more along the lines of 250 2M connections being multiplex over
> an ATM network onto one 100M ethernet port at the ISP end.

So I assume one also needs to take into account the maximum real-world
throughput of a 100Mb ethernet port is nothing like 100Mbits / second.
Most likely this is going to peak at 20Mbits / second, max. What this
implies is when applying this 'hypothetical' definition of
contention ratios, in practice this is more likely to become 25:1.

Also, if the ISP decides to simply slot a 1Gbit ethernet link into the
data stream, can they legitimately claim their users now benefit
from an uprated link with a contention ratio of "0.5 to 1" ?!!!!!!!
:-(


David Bowles
Education Support / TeacherLab


< Previous Next >
Follow Ups
References