Re: [homenet] ISIS wifi testing

Michael Richardson <> Fri, 16 October 2015 19:35 UTC

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From: Michael Richardson <>
To: Mikael Abrahamsson <>
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Date: Fri, 16 Oct 2015 15:35:42 -0400
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Subject: Re: [homenet] ISIS wifi testing
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Mikael Abrahamsson <> wrote:
    > The setup is that I set up a WDR4900 with one connection to the
    > Internet (not really relevant), and one wired connection to an Ubuntu
    > machine. I then set up two additional WDR4900 on my sons tricycle, plus
    > a laptop.

On his tricycle, so you can move it around, I guess.
I think that it's R1/R2 + C2 that are on the tricycle.

Let me suggest two additional "challenges"

1) get a $20 hands-free phone.
   Can be found at garage sales. People get rid of them for a reason.
   Emphasis on: "Enhanced analog 2.4 GHz technology"
   meaning, when off the hook, it eats all of channels 1 and 2.
   (it also, uses 900Mhz for the other direction. Weirdly, it doesn't use them
   in the direction I'd think would reduce battery drain...)

   Repeat your experiment.

2) get a Lexmark printer, like:

And well, just plug it in.
My experience with them is that every 3-5 minutes, it announces itself on all
802.11b channels (or maybe it's just straight 802.11g without any care about
listening for b-type users first).  There is no way to disable the wifi that
I found short of the power cord, even if you only care about USB connection.
My neighbour had one of these: its why we switched to 5Ghz.
   (I might not have the exact model right)
In the end, their kid consumed too much ink, they bought something else,
and they lock the power cord up so it can't be used without permission.

You might want to create a network like:

C1 +----+R3            +      +         +
          +            +      +         +

Or perhaps R1/R4 are the same router with two ESSIDs configured.
Maybe seperate R1/R4, R2/R5 (they are connected by cables), so that they are
in different broadcast domains...

And also make W1==W3 ESSID, and W0==W2, just in different places, and walk
the tricycle around.  Do you have some metals doors?
{and don't forget to deduct the price of the tricycle as a "research cost"! :-)}

That's particularly interesting because there are only a single set of TxOps.
Note that this is essentially very similiar to the problem outlined in (physical)
traffic planning by Brian Hayes at:

]               Never tell me the odds!                 | ipv6 mesh networks [
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