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 From:  Adam Nellemann <adam at nellemann dot nu>
 Cc:  m0n0wall at lists dot m0n0 dot ch
 Subject:  Re: [m0n0wall] bandwidth limiting
 Date:  Tue, 11 May 2004 15:17:08 +0200

Dinesh Nair wrote:

> On Mon, 10 May 2004, Tony Pitman wrote:
>>Well, it is the incoming traffic that is going to be the big problem. I
>>need to be able to limit how much bandwidth someone can use for
>>downloading and web browsing. Please expand (without rehashing too much
>>as you indicated) on what you mean.
> incoming traffic reaches your m0n0wall before it can be shaped. if it's
> reached your m0n0wall, it's already put a load on your incoming T1, thus
> serving no useful purpose in reality.

While this is true, some time ago there were some posts to the 
contrary (by someone apparantly with a great deal of knowledge about 
these things). It would appear that inbound shaping can have some 
effect, due to packets being dropped, which will apparantly cause most 
servers to slow down transmission of new packets or something along 
those lines?

> however, since you have dual interfaces, you can set outbound traffic
> shaping on your wan link and outbound shaping on your lan link. the
> outbound on your lan should be equivalent to the inbound on your wan, and
> under your control.

While I'm not sure, I should think it would have (nearly) the same 
effect if the inbound shaping is done on the WAN interface, at least 
if a queue is used, as m0n0wall should then accept the packages and 
hold them in it's own queue, rather than simply dropping them. But as 
mentioned, it would appear that sometimes it is preferable that 
packets are dropped, so..?

= = =

I guess the issue here is to provide a static "cap" on the inbound 
bandwidth of 128K, so a given user only gets what has been paid for. 
The issue of optimal WAN line usage shouldn't be that important (after 
all it is a T1 line!) and as mentioned there is a good chance that it 
will actually result in rather good line usage even so.

I would certainly try shaping both directions (possibly experimenting 
a bit to see if inbound should be done on the WAN or the LAN IF), only 
if this seem to cause some kind of problem would I consider removing 
the inbound shaping (in which case I'd try to do some clever outbound 
ACK shaping and such instead).