[AusNOG] Why not Symmetric ingress and egress?

[Sam Silvester]

On Thu, Jun 17, 2010 at 8:54 PM, John Lindsay <JLindsay at internode.com.au> wrote:
>
> Our experience, particularly with a couple of hundred thousand ADSL subs is that asymmetric access results in fairly balanced in/out traffic at the head end presumably because quite a lot of the back channel is P2P and it will use whatever it can find.
>

I wonder however if that's more a result of the fact that most
Internode plans are "unmetered uploads" - wouldn't that somewhat bias
traffic, as if somebody downloads a lot they get shaped, whereas if
they upload a lot, no dramas. By means of comparison, we meter
uploads, and we see a much less balanced traffic profile at our BRAS.
As such, I don't think your experience is universal.

FWIW, I think that symmetric would be nice, purely because then you
aren't locked into assuming that upload bandwidth will be constrained.
With the number of applications now (Skype & any other VoIP related
program come to mind) that actually send more than just ACKs, I think
that the old "100/7" ratio (to steal your numbers) could probably be
reviewed.

Whilst I still don't upload lots of data all the time, when I do, it
doesn't take much more than one or two largish video uploads or a
couple of photo album uploads to have me cursing the limits of my
ADSL2+ upload speed.

Sam