Friday, January 30, 2009

Bag[ged ]rami

After spending more than enough time down in the city, we got back to the roots of what this whole thing is all about--pushing data ahead of infrastructure on the fringes of civilization. It is on these fringes that the real battles here are fought, against hunger, poverty and Talibs. Considering how economically depressed it is here, the cities manage to function reasonably well, especially in our prime location as the first major anything on the road from Pakistan. You need not walk far, however, before subsistence farming and scavenging the barren earth for anything of value take over as the primary modes of existence. Somewhere in between there are millions of people teetering back and forth between progression and stagnation with the prevailing winds. In this boundary zone FabFi can be a lifeline to Modernity, or better (by about a century).

We spent yesterday and today bringing up a link in the village of Bagrami. With the Shop Bot still lacking power, I hacked up the small antenna design to fit on the laser cutter and made a pair of snazzy acrylic numbers complete with holes for zip ties.

Flying solo today, I had a golden opportunity to discuss some of the problems that face these boundary places with the people who live there every day. (Thanks to Nekibulah and most of his family, many of whom are teachers or otherwise associated with the local school).

"In Afghanistan, we have very little learning," he says. "Both teachers and students must work outside of school to get money, so it is difficult to focus on our studies."

Paraphrasing the rest: Teachers are paid $50 a month by the government, which is not enough to support one's family (Nekibulah has 18 people in his) so most teachers take second jobs after school. When they become exhausted, teachers often skip teaching their lessons, telling students to "do something [waves hands in a shooing motion]. I am tired" (did I mention that classes have as many as 100 students?) Students share the same problems, forced to work instead of concentrating on their studies. Oh yeah, and they also don't have any resources... at all.

In places like Bagrami, access to computers and the internet can be life-changing. Nekibulah's brother, for instance, is interested in medicine but has absolutely no access to any information on the subject. A simple google search for "health" had him excited in no time at all, and I was glad to watch the attending group devour a page on women's health (including sexual health) without even batting an eyelash. In contrast to his brother, Nekibulah was more interested in information about Afghanistan and Islam. The tension between traditional cultural values / religious beliefs and the desire for the opportunities of western (for lack of a better term) society is palpable in these moments of discovery. "Are there Muslims in America?" "When you have a guest in your house would you have tea together?" were questions asked with a note of apprehensiveness as if my response might deepen the inner conflict between old and new. On some level I can understand. Living peacefully in a close-knit community amidst beautiful fields cris-crossed by winding irrigation channels and dotted with wispy trees with a background of incredible mountain views sounds pretty darn good. One can only hope that Wikipedia will convince these new users the west isn't all bad before they find the porn.

All the photos HERE.

Thursday, January 29, 2009

Pleasant surprises, Bright Futures?

I stand corrected on my assumptions about the hospital. Not only was the power still on, but a grate had been installed to lock the tower roof. I could be a cynic about why the grate was installed and who installed it, but equipment not getting stolen is equipment not getting stolen, so I digress.

The trouble with the link was an unassociated router on the big link STA, which was fixed by the simple calling of "wifi" at the command line. After fixing the link, I spent about an hour teaching two of the hospital IT staff all about the system and giving them login access for all the links vertically from their endpoint up to and including the tower end of the big link. One of the two learned very quickly and was excited to come to the FabLab to do more.

Having users acually excited about understanding FabFi fits nicely into the master plan, which is to create a community of users that rely on each other for IT support of the system. A big question for me at the moment is the community building aspect--what will be the best way to get all of these disparate people to talk to each other? Already we have a FabFi splash page in the works, but that's just a start...

Wednesday, January 28, 2009

Sigh

After days of phone calls regarding a downed link at the Public Hospital, Brandon and I went to town to make a social call at their offices. Having already tunneled all the way down to their link, we knew everything was up and running, but we decided the social call would be worthwhile to prove a point. We arrived to a hero's welcome with tea and the usual accouterments, and the proceeded to point out that the ethernet cable coming from the antenna was simply not plugged in. (note: they plugged in this cable in the first place) Feeling particularly bold, we also tried to explain to the hospital director that his use of the wireless from the FabFi link was not correct, and that the hospital would need to get a wireless router for themselves. My guess is that this did not go over well, as the water tower, which receives power from the hospital, has been down since late yesterday afternoon. I hate to jump to conclusions, but it wouldn't be the first time we've seen this sort of reaction from the hospital, where politics trump all, even when it defies any reasonable logic.

On the technical side, all the netmasks on al lthe links have been changed to 255.255.255.0, and the SSIDs have been hidden without any negative effect on the network. Initially this change seemed to open up everything to everything, but after everything settled for half a day, we're now seeing the proper behavior of being able to ping up and across but never back down.

Thursday, January 22, 2009

Hello Mr. Fatpipe

This is a little belated, but better late than never...

When FabFi goes linking, FabFi goes big. After verifying that there was a good link from the FabLab on our last outing, Andreas, Smari and I went into networking high-gear. Smari set up a linux box with a proxy server to run DNS, dhcp, and a proxy server to cache web pages and locally mirror MIT Open CourseWare (we did a local dump of wikipedia too, just for kicks). Meanwhile Andreas and I worked out a network topology for the rest of the system that would allow us to daisy chain links easily. In retrospect, it could have been a lot cleaner, but here's the breakdown, starting with a 10.0.0.0/8 network.

  • FabFi router subnet (serves all FabFi links) = 10.1.0.0/16
  • AP wan = dhcp (netmask /8)
  • AP lan = 10.2.1xx.0/16
  • STA wan = 10.2.1xx.0/16, statically assigned
  • STA lan = 10.3.1xx.0/16
  • Each STA/AP pair shares the same class B address
This works well for allowing us to daisy chain links, but the open netmasks allow some strange things to happen with dhcp addresses. I believe, in retrospect, these could be restricted to /24 without restricting the daisy chain feature.

The firewall is currently forwarding everything which seems to be working fine, and computers on the FabFi network can't see any of the computers locally at the FabLab or the Taj except for the OCW server, so I'm not worried about security (yet). At the same time, the SSIDs for the wireless links are still visible, and somehow people at one of the downlinks have jumped onto the AP directly with their laptops. This is puzzling since there's not supposed to be dhcp available from the AP.

Anyway, on to the numbers. After doing some peaking with a pair of big antennas using window screen as the reflective surface, we achieved -67dB over 2.41 miles. It turns our we almost have line of sight, though we're shooting through one very large foliated tree. Data throughput is 4.43Mbps to the FabLab with virtually no packet loss and very reliable ping times (Amy got 1.8Mbps to the web from one of the downlinks) As you can see below, we moved the whole setup down to the catwalk level of the tower and tied it down. Plastic bags and tape served as weatherproofing, and a line from the hospital is providing the juice.
After over a week of intermittenet rain and wind, everything is still functioning well to the tower, and both downlinks are connected, though there have been some user complaints of patchy service, most likely do to our fiddling with the network here at the Lab.

Thanks to a confluence of circumstances, I'm in the field for another two weeks, during which time I hope ot be able to tie up a lot of the loose ends and make a couple more links, the coolest of which will be Bagrami School (more about that soon). Stay tuned.

Thursday, January 15, 2009

I get high with a little help from my friends.

One of the tastiest, and most annoying features of working in Afghanistan is that everything you do and everywhere you go is through personal introduction. This is great if you're hungry or thirsty, as personal introduction inevitably means tea or lunch, turning what could be a 15 min endeavor into a multi-hour affair. On the upside, once you're in with someone, you've got your run of their domain. In today's case, that run happened to include a 40m water tower at the Public Hospital in Jalalabad. After seeing no signal whatsoever at OM yesterday, possibly due to an antenna misalignment at the FabLab (below),
we bumped ourselves back .2mi and up 2 storieslinking up at -77db with virtually no packet loss using a 4footer window-screen clad reflector on the FabLab end and our tried-n-true 2 footer on the remote end. Looking at the background noise, you can hear crickets. (the solid line on ch 9 is noise from the local router)Computer troubles prevented a throughput reading, but we'll work that out in the next couple of days and make the trek back out.
The FabLab is just past where the smog blots everything out at the base of the mountain...

More photos here

Monday, January 12, 2009

Oh, Mercy!

FabFi is on the ground in Afghanistan as of 1/6. The luggage had a rough trip (it exploded in Dubai), but we got all 250lb of it here with no casualties. Of course that's only the beginning of the battle. The shop-bot is still not running, I need to go to the market again in the morning to get chicken wire for the backup antennas we shipped over here, and the first link we're going to attempt tomorrow doesn't even pretend to have line-of-sight. (thanks for mentioning that in the site report...) 2.2mi is cake with the four-footer, sure, but we've never done anything without being able to key the other site in binoculars and this one might not even have adequate fresnel zone. Both buildings are four stories, but there's less than 40' elevation change between the Taj and there, so pretty much anything in-between will be getting in the way (joy). I don't have high hopes that it's going to work without a tower, but I've been suprised by this system more than once so far, so might as well give it a shot...