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 From:  "Mitch \(WebCob\)" <mitch at webcob dot com>
 To:  "Hugo Hamel" <hhamel at privalodc dot com>, m0n0wall at lists dot m0n0 dot ch
 Subject:  ATM WAS RE: [m0n0wall] RE : [m0n0wall] Traffic Shaping issue
 Date:  Tue, 27 Jul 2004 08:06:34 -0700
> You are correct with your answer. DSL is a shared technology with no
> garantied bandwidth. It works just like a modem. You connect to an ISP,
> this ISP brings your traffic back (called backhaul) to its main site and
> then gets transferred to the Internet. The Backhaul portion is (most of
> the time) ATM UBR traffic. UBR means unspecified bit rate. This kind of
> traffic is a lot cheapper for ISP.
>
That does Hugo... our carrier tells us that the ADSL does have a minimum
channel, which is MUCH smaller than the purchased speed of course... a 1.5Mb
has a committed availability of only about 512kb!

But you are the first person who seemed to know about this stuff, so I'll
ask a question that I was searching for before incase you have insiration.

My understanding is the ATM network provisions point to point links form
subscriber A to the ISP, and for subscriber B to the ISP. Subscriber A and
Subscriber B are on the same subnet. This means they can't communicate. A
expects B to be within it's broadcast domain, and vice versa, but ATM
doesn't work that way - there is no effective broadcast domain - all traffic
must be routed through ISP. So how do A and B communicate?

I've heard of /32 subnetting, but never seen it implmented in FreeBSD. I'm
going to start managing my own ADSL, which will give me the option of
running private addresses for A and B, which could mean that I can make them
be on separate subnets, but this isn't ideal - it forces me to do 1:1
natting for all those clients at the ISP, which will complicate things I
think....

Anyways... a little off topic, please forgive me, but I'm trying to do it
with monowall in the long run (possibly regular FreeBSD at the ISP though)

Thanks!

m/