
Wireless Installation in the Jungles
of Laos
In the summer of 2002,
we had the opportunity to install a wireless network in a newly constructed
gold mine in the remote jungles of Laos. It was really an adventure,
Laos being one of the most underdeveloped countries in the world.
Here's a brief synopsis of our trip, including some comical (although
nearly deadly) mishaps. Pictures of our excursion can be viewed by
clicking
here .
Just getting to the gold mine took
about 3 days: 2 days by air to Bangkok and then a short plane hop
to Vientiane (the capital of Laos) and a day and a half by pickup
truck over mostly bumpy, muddy dirt roads. The Lao people were friendly,
but very cutoff from the rest of the world. Most of the countryside
was jungle and rice paddies until we got to the mountains near the
mining camp. One of the first things we were told to look out for
were UXO's - unexploded ordinance leftover from the Viet Nam War.
UXO teams had to pick over the ground with a fine tooth comb, defusing
and removing old bombs, some of them quite live, before any construction
work could begin. You can see pictures of some of these bombs on the
web site.
The mine has a population of about
600 workers including a group of 50 or so Australians brought in to
manage the camp. They had hired us to install a 2.4 meter satellite
dish to receive and transmit IP traffic, to install a wireless network
in the camp to distribute the signal to the various buildings there,
and to install some IP telephones which would connect back to our
computerized PBX in Florida. Although my partner, Mike and I and are
fairly experienced with wireless and Internet, we had never installed
a satellite dish before (though we had seen it done) and our IP telephony
experience was fairly limited.
We only had 4 days to complete the
job, so we were happy to learn that the satellite dish had arrived
at the camp early and the 2 Australians who had hired us had done
the physical installation of the dish and the mount prior to our arrival.
That meant that as far as the satellite was concerned, we only had
to install the satellite transmitter, feed horn, satellite modem and
cables and point the dish. When we tried to point the 2.4 meter dish,
however, we ran into a problem. We needed to point it approximately
23 degrees above the horizon (a low "look angle"), but the
pipe it was mounted on only came up from its concrete base about 36
inches, so when we angled the dish down to about 35 degrees, the bottom
of it hit the ground. After reviewing the plans for the pipe mount,
we learned that the mount was designed for a roof-top, so that the
dish edge could extend beyond the lip of a building roof. It was never
intended to be embedded in a concrete base on the ground. We needed
to raise the dish at least another 30 inches to aim it correctly,
but the camp didn't have any pipes of the right diameter or strength.
What they did have, however, was a good carpenter who fashioned a
pipe extension out of the hard wood of a native tree for us! You can
see the pictures of this make-shift mount on the web site.
The most amazing mishap we encountered
involved the wireless setup at the central hub. We needed to mount
our base station radio (a NEMA box with 2 lucent radios and Karlnet
software) next to the Communications Hut - a small trailer powered
by generator that housed our router, satellite modem and network switch.
We originally planned on using a 20 foot pipe mount, but the line-of-sight
to some of the client buildings was not nearly as good as we were
told and we needed more height. A 50-foot tree with few branches and
a fairly straight trunk right next to the Comms Hut seemed the perfect
candidate. They brought us a crane from the construction camp and
hoisted Mike up near the top of the tree where he spent a good hour
screwing 2 flat panel antennas and the NEMA box to the tree trunk.
We were pretty proud of our installation and the height that it gave
us to reach the other buildings. We showered off (the camp and much
of Laos as a whole is a very muddy place) and three of us returned
that evening to the Comms Hut to point the satellite dish and bring
the satellite circuit up. We had to do this at night since we were
11 hours ahead of our Florida office with which we had to coordinate.
We had an Iridium satellite phone for communications which worked
reasonably well (at $2/minute). After about an hour and a half of
tweaking the dish position and feed horn polarization we had a pretty
good lock on the satellite and were told by the Florida group that
they'd call back in 10 minutes for the final "turnup" of
the circuit.
We were pretty excited since we hadn't
done a satellite install before and considered this the most uncertain
aspect of our venture. About 5 minutes passed when we were a sharp
"CRACK". At first none of us knew what the noise was, but
a second later a series of crackles and creaks followed and Mike,
who was the only one standing several feet away from the Comms Hut
yelled, "Look out! The tree!". Roy, one of the Australians,
and I didn't have time to ask "What tree?". We could hear
it coming down on the Comms Hut from the opposite side that we were
standing against. Roy was near the door and dove inside the trailer.
I just had time to flatten myself up against the outer wall of the
trailer and hope I didn't get crushed. The tree landed smack on top
of the trailer, and stretched across it, nearly puncturing a water
purification tank and coming within feet of our satellite dish. Nobody
was hurt, although the impact shattered the flourescent lights in
the trailer which landed all over Roy. It also knocked out our power
for about a day and damaged the trailer's AC fan. And, yes, of course,
it was the very tree we had mounted our wireless setup on that very
day. About 10 feet up the trunk we could see the tree was all eaten
out by termites - the wireless gear must've been the straw that broke
the camel's back. Amazingly, the wireless equipment was intact, still
on the tree and landing past the trailer just a couple feet shy of
the water tank. You can see the pictures on the web site. When we
called back to Florida and told them to scrap the plans for turning
up the circuit that night because a tree knocked out our power, they
didn't believe it.
The next day we were the talk of
the camp. They wanted to use Mike to clear the trees in the mine field
by hugging them, so they would fall down the next day. What happened
the next day made that idea seem a little less funny. The camp had
a lot of construction resources, and at our request, a pipe welder
bonded 2 20 foot pipes to give us a 40 foot mast for our new, termite-proof
mount. We installed it that day alongside the comms hut. There was
a clump of small trees near the pipe mount that threatened to block
our signal, so we asked to have them removed the next day. Of course
we heard all the jokes about how we should just put an antenna on
them so they'd fall by themselves. Well, that afternoon during a heavy
rain, the most obstructive of the trees did fall, all by itself, and,
yes, it landed on the Comms Hut. (We have those pictures on the web
site, too). Fortunately, this one didn't do any damage, except to
increase the barrage of jokes from the camp workers, and we did get
the satellite circuit turned up that night, and the wireless connections
the the next day.
We did, in fact, eventually succeed
- the IP phone quality was quite good, even with the 750 msec latency
of the circuit which was routed via satellite to Germany and then
via fiber to New York and down to our NOC in Florida. We didn't know
we had succeeded till several days after we left, however. Despite
all our careful planning (shipping 16 boxes of equipment through customs
into Laos wasn't easy), we had, of course, forgotten one little piece
of vital equipment: an AUI->RJ45 transciever to plug into the back
of our Cisco router. We were basically able to verify we had satellite
connectivity and Internet connectivity all the way to the router.
We also verified wireless connectivity to the 3 sites we setup. But
without the transceiver, we had no way to plug the Cisco router into
our hub and bring the Internet to the wireless network and IP telephone
system. While a transceiver costs about $20 or $30 anywhere in the
U.S., it was unheard of in Laos and had to be ordered from Thailand,
arriving well after we left.
Fortunately, all the mine workers
had to do with the transceiver when they finally got it was to plug
it in, and then they had telephones and Internet. The Australian contractors
returned later and replaced the 40 foot mast with a 90 foot mini-tower
for better wireless coverage. I'll post those pictures when I get
them. You can also read about our trip in this NetworkWorld
Article.
Now they've asked if we want to do
a similar install in the Congo. I'm not sure we will, but if we do
we'll definitely bring our hard hats.
Tom Fantacone
Vice President
Nationwide Computer Systems, Inc.