home 
wiki
wiki
Spelling: NodeHYA
LOCATION
HYA is located in Kew on Selbourne Rd. (near the corner of Glenferrie
Rd and Cotham Rd).
LOS
Unfortunately I am not quite high enough to crest the ridge to the
north but am on the 60 meter contour line. I have visibility to St
Kilda junction to the south west through to Camberwell in the south
east.
HARDWARE
I have a Linksys WRT54G running as a local AP with a couple of
Minitar MINWAP ready to use for dedicated links to other (hopefully
distant) nodes. I chose these units because I wanted to be able to
change the software and tweak and tune it.
ANTENNAS
The Linksys has a slotted waveguide made out of down pipe (Clark)and
the Minitar's have 65cm offset satellite dishes ($33 from Melbourne
Satellite) using bi-quad feeds (Martybugs).
NETWORK
I have a public segment as part of the wireless node and then tunnel
it through my other networks to the Internet. The diagram shows the
segments and the routers only.
STATUS
The Linksys is up and running as are the two Link radios (though they
are not linked to anything yet). It has NoCatSplash [1] to present a
sign on page. At the moment it is in the front upstairs room
overlooking Camberwell, Once the weather clears a bit then the antenna
will go on a TV mast attached to the chimney.
I'm working on changing the router configuration to flip the firewall
around. Once that is done I will connect it though my internal LAN and
the Internet.
SERVICES
Depending on links I may provide limited Internet access for some
service/ports. I thought it may also be useful to do a bit of
tunneling to link up other with other regions/nodes by tunneling
through the Internet, as a temporary solution until the mesh gets a
bit denser.
WHY USE AP\'S NOT A LINUX BOX?
Good question. I was originally going to stick a few cards into a
Mini-ITX based box but then I realized that the AP's were cheaper,
smaller and used less power. That was a compelling enough reason the
try them first. The Minitar is so small that I am mounting it and the
bi-quad antennas in the same weatherproof enclosure on the satellite
dish LNB arm. No antenna cable run and a single cat 5 wire back to the
Linksys carrying Ethernet and power.
LINKSYS FIRMWARE
I am currently building firmware for the WRT54G. I have taken the
original Linksys development environment and moved in a few modules
from the various distributions that people are building. I'm probably
closest to the EWRT version than any other. I have NoCatSplash [2],
dropbear, snort and a few other goodies on it at the moment.
I use one of these routers internally in my home and found that the
cable connection was timing out every 5 minutes. It turned out that
even though you provide the IP address of the login host it tries to
do a DNS lookup on the HB server without appending the domain, so when
the HB port comes back it would open the correct port but with an
address of 255.255.255.255 - No wonder it was never getting a
heartbeat. The heartbeats come in about 5 min 13 seconds with the
occasional stretch. Its been up for about 45 days now without a
problem.
MINITAR FIRMWARE
I haven't flashed the Minitar yet but have been working on getting a
complete image to flash - the dev. environment that was released is
incomplete so you need to extract stuff from an official firmware
version. I have been spending a bunch of time in the boot loader code
and am waiting till I have put together a Flash programmer and
socketed the chips - it's too easy to brick these things.
Wasted a lot of time on this little device. Once that issue is passed
then I have a few changes ready to test. The major one is to remove
bridging - when you have one of these acting in Client mode to a
remote node you don't really want to bridge but rather have it route
between the local and remote LAN segments. My MinitarHacking [3]
continues, and once it have it stable I will release the images that I
have been building.
The bootloader is working well now and can be chained from the
original bootloader. Adding BOOTP client functionality now so it can
boot from a TFTP server image and looking at mounting the filesystem
via NFS. With only 8MB RAM the device is so tiny that you need to
think seriously about how much space you can give over to applications
(the kernel takes 2 alone, then about 3.5 for the ramdisk).
Links:
------
[1] http://melbournewireless.org.au/?NoCatSplash
[2] http://melbournewireless.org.au/?NoCatSplash
[3] http://melbournewireless.org.au/?MinitarHacking
[EditText] [Spelling] [Current] [Raw] [Code] [Diff] [Subscribe] [VersionHistory] [Revert] [Delete] [RecentChanges]