(LCA) 2011

Every time I attend (LCA) I am reminded that it has a couple of really unique features:

It’s a really friendly, genuine, relaxed conference. So different to trade shows or academic conferences. No one is there to sell you anything or to advance their list of publications. People attend because they are interested in geeky stuff.

The second is intellectual stimulation. A lot of projects get started or greatly advanced at LCA. When I attend a talk, ideas start flowing, sometimes in completely unrelated areas. Several people said the same thing to me this week, “Well, I wasn’t really that interested in that talk, but then I got this idea about…….”.

That sort of creativity and motivation has a lot of value. Here are a few highlights.

Getting Your LCA Paper Accepted

I met a guy on the paper review board and thanked him for accepting our paper. We started talking about what it takes to get a LCA paper accepted. About 70 were accepted this year from 180 proposals. Some tips:

  • They encourage papers from outside the Sydney/Melbourne Australian population cluster, to ensure a good representation from around Australasia and beyond.
  • LCA likes practical applications of open source, rather than your great new pre-Alpha software that only runs on your laptop. For example our Dili Village Telco proposal talks about open source helping end users in a developing country.
  • A good track record helps. Actually it’s more accurate to say a bad track record won’t help. If you didn’t do a good job last year then you may struggle with this years proposal.

Many other people have written on this topic, for example Rusty Russell and Mary Gardiner. Sam Varghese also has an interesting article on how this years papers were selected.

I feel pretty honoured to have been accepted to talk at such a conference. To me it’s a sign that my work is on the right course.

OLPCs and Effective Learning Outcomes

I attended the OLPC talk by Sridhar Dhanapalan who is the CTO at One Laptop per Child Australia. They have deployed 5000 XOs in Australia which is pretty cool, as they operate largely as a charity without government support.

My pet interest with the XO is making sure they are effective tools for teaching. For example students using them should have better educational outcomes. They should make teaching easier. This stems from my interest in IT for development. In the developing world I see a lot of well meaning projects focus on technology rather than focussing on delivering effective benefits to end users. The more exciting the technology – the bigger this problem is. It’s a really easy trap for geeks to fall into. I should know, been bitten by this one myself many times.

Education in remote Outback Australia is especially challenging.

I have a little practical experience in teaching with XOs. In 2009 I took some XOs to an Outback school and with my daughter spent a week teaching Aboriginal children with them. It was damn tough and I gained a lot of respect for teachers. The locations are remote, schools are small, staff turnover is high. Creating lesson plans and keeping kids meaningfully engaged for 1 hour a day is really hard. Compounding this were other problems, e.g. many of the children have irregular school attendance, problems at home, constant illness, and even disabilities such as infection-related hearing loss. In a 6 year old. This is Australia’s third world.

So I think what OLPC Australia are working on part of really, really tough problem – educating kids. There are no easy solutions, and it will take some time, plus trial and error to effectively improve outback education using XOs.

I am concerned about the focus of XO work. If you have a hammer, everything is a nail. The XO is geek wonder-hammer. I would love to see more focus on wetware, and less on hardware and software. Effective teaching with the XO rather than more technology development.

So at 2012 it would be great to see a teacher from the Northern Territory Education who has used XOs in a classroom for 12 months. Lets hear about what works, what doesn’t and how the learning outcomes are being improved.

Thanks to a teacher friend for helping out with this section.

Vint Cerf

Great keynote by Vint Cerf.

He made the understatement of the decade: “I am a little bit embarrassed about the 32 bit IP address limitation, as I was the guy who made the decision.” (!) “At the time I just thought it was an experiment, but it (the Internet) went a little further than I thought….”

He spoke about bit rot, e.g. will we be able to run 20th century software in the year 3000? Or will the hardware and operating systems be long extinct?

Vint is currently hacking the Interplanetary Internet, which uses Delay Tolerant Network (DTN) technology. Space is big, so your ping time to Uncle Martin on Mars is about 40 minutes. So you need protocols that can handle this, protocols that are delay tolerant. By coincidence I attended a conference on DTNs in September. DTNs are currently used for getting data to remote communities, for example using a helicopter or scooter as a data “mule”. At that conference some people were saying that with the growth of broadband around the globe DTN technology would soon be extinct. Maybe, for terrestrial networks. However our expansion into space will happen some day and you just can’t get around the speed of light.

A neat idea was re-purposing old space probes and satellites as “routers” at the end of their mission.


Speaking of expansion into space….

Bdale Garbee’s rocketry talks are always very popular. This year there was a mini-conf stream where you could build and fly your own rocket. This was very popular, many people working on their rockets all week.

Here are a couple of proud Rocketeers, Tim and Joel:

Dili Village Telco Talk

Organising LCA is a huge effort. This year they had to uproot the whole conference to another venue at 1 weeks notice due to the Brisbane floods. As if they didn’t have enough work to do. I would also like to mention the kindness of the organisers for supporting Lemi Soares to travel from Timor Leste so we could co-present. Lemi is my partner in the Dili Village Telco project. Lemi got a lot out of LCA, and he met many people. Face to face is so much better than electronic contact.

We had a full house for our talk. As a speaker I can tell you this adds a huge amount of energy. Thank you very much to those who came along. A lot of people came up and thanked us later which was wonderful – you should so this if you liked a talk. It means a lot to a speaker. It adds a validity and importance to our work that we just don’t get when we sit behind a computer all day.

As a LCA speaker the first thing I do is check is my slot and who is speaking at the same time. Is a really well known good speaker like Rusty talking at the same time? Is it that %$^# cute robot bear that sucked my crowd away last year in a parallel session? Nope? Phew, we are set!

I have spoken many times on the Village Telco, so to keep it fresh I wanted something different for this talk. So we added a few slides that describe what it’s like to be a developing world geek. I wanted to capture the audiences attention and transport them into the shoes of a developing world hacker for 45 minutes. This ranges from the annoying (power blackouts) to being shot at by soldiers and thrown in jail by an occupying force. This seemed to work very well – the typing on laptops slowed, and faces emerged from behind them. It set the scene for our talk which deals with the unique telephony problems faced in the developing world.

Here are our slides in Open Office and PDF format, and here is the video. I found the picture below (of me) on the OMG Ubuntu blog.

After the talk I had an interesting suggestion for Wifi links with strong interference – use an optical long distance link such as the Ronja project.


Paul had a good talk on Serval, which uses mesh networks formed using smart phones. Now one problem with this approach is range. For example a smart phone in your pocket will be “range challenged” compared to a Mesh Potato mounted on your roof. Although if you get the Wifi broadcast rate just right all that microwave energy will keep your pants nice and warm. A possible solution (to the range issue, not warm pants) is to deploy some additional “relay” nodes at strategic locations, generally the higher the better. Paul had the brainstorm of using a tethered helium balloon – which he tried for the first time at LCA.

If there is a balloon doing something geeky, you will find Joel! Here is Joel (again!) launching the Serval Balloon with Google G1 phone payload below:

Thanks also to Mark Jessop for putting a lot of work into this experiment, supplying the balloon, and working on the required government clearances.

Paul reports some success with the idea, but encountered similar interference problems to our networks in Dili. The omnidirectional antenna on the balloon payload was receiving packets from every Wifi radio on campus. In contrast signals received from the balloon by radios on the ground were very good as their was an excellent line of sight path.

Every Router a Potato

I have had an idea kicking around in my head for a while. There are a lot of 802.11bg routers getting tossed out as 802.11 technology advances. What if we could recycle them into Mesh Potatoes, then ship them off to a developing country where they would be really useful? Now, what if we did this recycling work at a 2012 miniconf?

So the plan is:

  • Develop a low cost FXS interface circuit, like the $10 ATA. This would be a small daughter board that can connect to the RS232 serial port and GPIOs of any OpenWRT-capable router. Like a customised Arduino with some analog components to interface to a telephone.
  • Get people to bring or donate old routers to 2012.
  • At the conference, run a tutorial session where we solder the $10 ATA daughter boards, then attach them to the routers. Maybe add another small circuit to make the 12V port robust to developing world power problems.
  • Another team could handle flashing the routers and testing. Part of this job would be developing images for a range of previously popular routers.
  • At the end of the conference, ship them all off to a developing world country. If we ship in volume it will make the shipping cost quite economical. We would really help a lot of people, recycle some e-waste, and have a lot of fun building cool hardware and hacking routers.

Like me, the people attending really want to help other people. We saw that in the response to our talk, and the questions afterwards. They are fascinated by the idea of using technology to help people in the developing world. But they don’t know where to start. The Every Router A Potato (ERAP) project is a way for anyone with a router and a soldering iron can help out.

4 thoughts on “ (LCA) 2011”

  1. Out of curiosity, have you done any checking to see what other bands look like in places like Dili village? I’ve followed your progress for some time and was surprised to hear that 2.4ghz was so crowded. I guess it makes sense since 2.4ghz equipment is so inexpensive relatively. I’m curious how other bands like 900mhz, 5.8ghz, etc are like over there.

    1. No we haven’t checked other bands, although the guys are trying some 5GHz links at the moment. One of the goals was to make the network work with the Mesh Potato, so even if another band was clear it wasn’t a practical option. Dili is a template for many other Village Telcos around the world. More important to find out how to to make the 2.4GHz kit work even with interference.

  2. Hi David,

    Addressing your concerns, OLPC is an educational programme. The
    devices (‘laptops’) we give to children are called XOs. We at OLPC
    Australia take education seriously, and all XOs are given as part of a
    comprehensive and sustainable educational programme. That is a point I
    tried to stress at the beginning of my talk.

    Moving on from that, I focused on the technical elements. After all, is a technical conference. The goal was to engage the
    hackers in the room and give them some insight into our technology.
    Similarly, the talks we give at education conferences focus much more
    on the educational benefits and less on the technology. It’s a case of
    tailoring the message to the audience.

    My secondary speaker, Ian Cunningham, has many years of teaching
    experience, and is heavily involved in the OLPC rollouts in the
    Northern Territory. His role is a technical one, but with his teaching
    experience and constant contact with teachers using the XOs in their
    classrooms, he is has an appreciation for the situation and challenges
    faced in schools.

    I do appreciate your feedback, so feel free to let me know what you
    think. I also invite you to take part in our development community:

  3. Hi there, could you change the link text “this page” to “Mary Gardiner”

    Here’s a quick “patch”
    Mary Gardiner

    Saying – “Many other people have written on this topic, for example Rusty Russell and this page.” naming one of these people and not the other unfortunately contributes to the invisibility of women in computing.


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