Re: [Help-gnunet] bandwidth on ADSL

[Christian Grothoff]

On Monday 07 Jun 2004 4:35 am, dot wrote:
> Hi fellow GNUnetters,
>
> I have finally set up a dedicated GNUnet box, and it's cheerfully chatting
> away with other nodes, but I'm not sure how best to control its bandwidth.
>
> I have free upstream traffic, but I pay for downloads after a certain
> threshold is reached.
>
> Do MAXNETBPSDOWN and MAXNETBPSUP work averaged over the uptime?
> And how accurately (should I rely on it)?

>From what I see, you can pretty much rely on it.

> Will MAXNETBPSDOWN really keep my downloads within quota, or will other
> nodes (even non-malicious ones) tend to overshoot the mark?

I have not seen it overshoot the mark with any recent version on average over 
even moderate amounts of time (say an hour or so).  If you look at the 
minute-level you may get a 110%, but even that was rare.

> I don't really care about upstream (since it's free), so should I set that
> really high, or will it increase my downstream indirectly?

It does not directly affect the upstream, so you should be able to set it 
really high.  Nevertheless, you may want to limit it by your physical 
connection limit (or a bit below to allow for other applications).  Oh, and I 
have not tried this myself, this is just my best guess from how the code 
*should* work :-).

> Finally, does anyone know of some way (in GNUnet or otherwise) to regulate
> downloads so that any non-local traffic going out of this box will be
> strictly limited to N x gig per month?

Setting the MAXNETBPSDOWN to N * 1024 * 1024 * 1024 / 31 / 24 / 60 / 60 should 
pretty much do it.  You may also want to use the advanced limiting such that 
GNUnet will account for bandwidth used by other apps (note that this will not 
give you exactly N since a spike above MAXNETBPSDOWN by other applications 
will NOT be leveraged by GNUnet keeping traffic down for an equivalent amount 
of time, GNUnet will only reduce traffic by at most MAXNETBPSDOWN bps _while_ 
the other download lasts).

Of course, you can probably hack up something more elegant -- the code to 
parse network traffic statistics is already there (statuscalls.c), so if you 
want to hack up an additional mechanism that computes how much is left of the 
monthly limit and then dynamically adjusts MAXNETBPSDOWN, that can probably 
be done without too much difficulty.

Christian