Monday, October 27, 2014

Some interest in the open-source collapsible communications tower

It was nice to hear of some further interest in the open-source collapsible communications tower concept that we have worked on over the past year or two:

The project is ongoing, with a student looking at the existing design to better characterise it for operational use.

Sunday, October 26, 2014

Serval Mesh 0.92 is out on Google Play

After quite a delay, we have finally released a new version of the Serval Mesh.  

This is still an experimental release, but it does contain a number of important improvements, including but not limited to:

- The connect display has been greatly simplified, making it much easier to use, although there is still some way to go on this front.
- MeshMS is now encrypted by default (and incompatible with the 0.91 and older versions of MeshMS).
- Rhizome has been overhauled, and is also largely incompatible with 0.91 and older.

For a full list of what's changed since 0.91, the release notes for this version are available here;

If you want to install the latest version without using the play store, you can download it here;

Thursday, October 2, 2014

Connecting the internet, Outback style

This week I am up at Arkaroola in the Australian Outback together with Ülf, who is visiting us from Germany.  We are finishing the installation of some long-range Wi-Fi communications equipment that I began as part of National Science Week in August of this year.

The primary goal that we had planned was to connect the broadband internet service that is generously provided by MIMP to the Arkaroola homestead area, which includes the research facility in the old wool shed.

During National Science Week we explored a number of possible paths between the Arkaroola Village where the internet service lands and the homestead area.  The distance as the crow flies is about 5km, but with some serious obstructions in the form of iron-bearing hills and ridges.

These obstructions meant that we would need at least one relay station unless we could build some 20m high towers, and even then it wasn't certain that we would have clear line of sight. We had hoped to be able to put that relay station near a road to make for easy maintenance, however that proved impossible.

The next best option was to place the relay station near a walking track that goes over the Acacia Ridge which has line of sight to both the village and homestead.  The challenge is that this would require a 2km hike over rough ground to get the approximately 200m altitude over the valley floor -- a fascinating prospect when contemplating carrying equipment to construct a communications relay.

But first, here is Ülf assembling one of the the Ubiquiti NanoBeams:

This is one of the NanoBeams temporarily located beneath another access point on the observatory.  The NanoBeam is pointed at the Acacia Ridge relay we installed.

Ülf checking the configuration of the NanoBeam before it was attached to the observatory:

Rod fabricated a short tripod mast for the Acacia Ridge relay.  Here we are transporting it by trailer to the Acacia Ridge trail-head. Special thanks go out to the Turners who lent us their trailer, knowing that it would be covering several hundred kilometres of Outback dirt roads.

The mast is about 2m long, and made of heavy-duty 2.5" pipe, so it should last a long time ...

... however, it would be interesting to carry up the trail. Ülf had the great idea to make slings to make it easier to lug up the hill.  You can also see that we temporarily attached the dishes to the mast for ease of carrying.  Note that this shot was taken a rare flat and open section of the trail.  The trail averages about 7% grade and is very narrow with large rocks most of the way.

Most of the way up we stopped to take a shot of the view.  We started out from near to where the road disappears behind the rise in the foreground to the left.  The homestead buildings can be seen amongst the trees in the creek line a little further away.

Oh, yes, we also had to carry a pick-axe with us to dig the mast in.  All up I think we had about 30kg of gear with us.  We were quite warm by the time we reached the site, with the weather around 33 degrees C.

Another brief stop to enjoy the view:

Finally we reached a point where we could see the village in the distance, and which had some soil amongst the rocks allowing us to site the mast.

It is very pretty up there at the moment with all the flowers after a couple of good rains in the last few weeks.  Arkaroola and the surrounding country has a rather strange weather pattern, in that not only is the annual rainfall essentially random, but this randomness persists even for decade-by-decade averages.  So while some years and decades may average <100mm per year, it possible to get 300mm in a day.  In short, the rainfall is chaotic, in the mathematic sense.

These beautiful views of distant peaks got Ülf and I thinking about just how far we could reach from this site with a few more NanoBeams.

Finally, unpacking our load, and starting to install the mast:

There is not too much soil here, so we just dug the mast in as best we could ...

... and then piled lots of rocks on the legs of the tripod before installing the dishes.  It wasn't possible to carry the solar panel on this load, but we plugged the batteries in anyway, so that we could monitor the link from the village before heading back up with the 80W solar panel.

A few quick views over the dishes to verify that general alignment was fine. The relatively short distances (<3km for each link), meant that we didn't have to be too worried about super-accurate aiming.

A couple of days later we came back up with the panel, again carried by sling. The panel itself is an 80W BP Energy panel made here in Australia in the 1980s, back when Australia was at the leading edge of solar energy.  Sadly now our government seems more interested in digging up coal instead of positioning Australia at the leading edge of new industries.

It was now 44 hours since the NanoBeams were plugged into their separate 120Wh LiFePO4 battery packs.  One battery was too flat to run the NanoBeam, but the other was still going strong.  You can see the voltage difference empirically in the differential brightness of the LEDs.

Now, we are in Australia, so it would not be appropriate to build an installation like this without using at least some fencing wire.  The wire is there to stop the panel sliding away from the mast, or getting blown about in strong wind.

Here is the whole thing from the side.  What might not be obvious at first glance is the other piece of iconic Australian infrastructure that has been repurposed to build this relay: the recycled Outback Dunny (toilet) cistern that is being used to keep the weather off the electronics.

The cistern is placed under the panel to discourage any kangaroos or rock wallabies from trying to sleep under it, as well as reduce the UV exposure to the cistern and electronics.

We don't need to worry too much about the other Australian wildlife here, such as the poisonous snakes, deadly spiders, lethal octopii, despair inducing jellyfish (as distinct from the merely deadly jellyfish),  man-eating crocodiles and other biological hazards here.  The reality is that lightning kills more people and access points in Australia than all the biological things put together, with the possible exception of the Cockatoos and Possums (not to be confused with opossums).

Then it was time to head down to the homestead to find a suitable landing point for the link.  After looking at the number of termites (white-ants) in the verandah wood work, we opted to use an old children's swing as it was sturdy, and has the added benefit of being easily relocatable.

Here it is from the side.  The main hazard here is the dog which has already eaten the hose and might think that the ethernet cable is too tasty to resist.

At this point, all of the hardware is in place, but we discovered that one of the connections up on Acacia Ridge is unhappy, so it will be back up the hill in the morning.  Basically the link between the two NanoBeams on the ridge was broken. However, each separate link was working, so we were able to confirm that we had full 300mbit/sec bandwidth in each direction, with a very comfortable link margin of about 40dB.

You can see the very sad "LAN0 Unplugged" message here indicating that we didn't plug something in properly up on the ridge, or that the cable was faulty.  Most likely we didn't plug it back in properly after we made test VoIP and skype video calls from from up on the ridge.

So once we fix that cable, the Arkaroola homestead will have faster internet access than we can get back home in suburban Adelaide.

Meanwhile, this being the Northern Flinders Ranges, we found a Quandong tree.  This is also known as "bush peach" and which makes very tasty pies, such as the one cooked and ate tonight, although we cheated and used fruit that had already been collected here.  Thanks go to whoever collected and dried the fruit :)

Monday, September 15, 2014

Installing mesh extenders with Michael

An old friend of the Serval Project, Michael Adeyeye, is here with us in the batcave for the week to see what we are doing, and for us to share knowledge with him.

Apart from it being great to catch up with an old friend, the timing is perfect, as we have just finished our simplified installation process for the Mesh Extenders.  So Michael gets to test the documentation and procedure for installing Mesh Extenders, so that we can fix any problems.  All going well, we will finally have the initial batch of Mesh Extenders from the crowd-funding campaign ready to ship.

Thursday, September 4, 2014

Unbricking a Kindle paperwhite

I have a student who is working on real-time tracking of our University's loop-bus, together with displays at each bus stop to tell how many minutes until the loop-bus next arrives.

We are using Kindle paperwhite e-readers as the e-ink display will be easy to read during the day, and it includes a backlight to allow for night-time visibility.

The Kindles are fairly easy to root and modify, however, as with all these sorts of things, it is possible to mess things up so that it won't boot, i.e., bricking it.

We did indeed manage to brick our Kindle, and set off on a protracted adventure to work out how to unbrick it.  We were greatly frustrated by the lack of a clear and authoritative set of instructions on how to do this, and thus decided to fix this by documenting the process.

Tobias has summarised the method in the following gist:

If you find this information useful, please consider donating to

Thursday, August 28, 2014

Koruza open-source gigabit free space optical wireless

I have previously mentioned the great work that Musti and the guys in Slovenia have been doing on open-source free-space optical links.

Basically they use a gigabit fibre transceiver aimed through a lens in a 3D-printed enclosure to beam data over a distance of up to 100m:

They are now looking to test their design with a number of test stations around the world.

We would love to install one at Arkaroola in the outback, and see just how far we can make it work in the clean dry air there.

Our good friends at NLnet Foundation have offered to sponsor the hardware for a node if we can get 10 organisations to sign up to the Open Innovation Network (the OIN) with the reference set to "NLNET/KORUZA".

The Open Innovation Network is a great idea, basically being a defensive patent pool to protection open-source projects.  The really nice thing is that you don't need any patents to join.  We signed the Serval Project up a while back (we are licensee #808).  They have some big names, like IBM and Google as members and licensees.

So take a look, and think about signing up your project if you would like to help us get a  chance to test one of these:

Next to one of these*:

* Yellow Footed Rock Wallabies only after 5pm.

Monday, August 25, 2014

Arkaroola Long-shot Wi-Fi for National Science Week

Last week was National Science Week, which had my family and I heading up to Hawker Area School and Leigh Creek Area School and Marree Aboriginal School for sessions with students, before heading up to Arkaroola to attempt to install a wireless link between the village and homestead, with the goal of later extending it to the research facility in the old shearing shed.  

The school visits were designed to give students from areas that are fairly disadvantaged some taste of science week. It was great to see a number of the students engage well, including one budding inventor from Leigh Creek. 

I have some pictures from the schools, which I need to clear with the schools before posting them. But here is the rest of the week in pictures.

To depart Tuesday morning, I needed to bring some of the equipment home from work on Monday ready to pack.  My trusty cargo bike came in handy again:

Then it was driving north on the highway, staying at Hawker and Leigh Creek for the school visits before leaving the bitumen at Copley to head over to Arkaroola.  Fortunately the roads were all open and in quite good condition:

We arrived at Arkaroola about 5:30pm after dodging lots of Yellow Footed Rock Wallabies.  It was great to see so many of them, as they were very endangered in the past, but with a lot of conservation support have made a great bounce back.

Here is the Arkaroola Village, as viewed from up by the newer observatory:

It was great to be travelling as a family, and our kids had a pretty good time, even if Caleb didn't always want to be photographed.

 There is always a lot to see if you take the time to look around at Arkaroola, although a phone camera is not the best way to capture it.  As a result the following shot is a bit of a where's-Wally to find the parrot in the shot.

After the pre-breakfast walk it was time for the first of our hands-on sessions as we set about trying to install the communications link.

It was great to have a group of seven people for most of the morning as we tried climbing a few possible locations to mount the dishes, talking about the technology and various other things along the way.  Here is one of the older in our group as we picked our way down from the summit above the old observatory trying (in vain) to see the homestead vantage point.  I did have a shot with the whole group, but it seems to have been lost.

 Here is the "Telstra pit" on the top of the vantage point behind the homestead that we were trying to see from by the old observatory.  This pit carries the land line from the Telstra microwave relay on the vantage point down to the homestead.  We did have a chuckle about the in-congruency of the nice neat cement pit cover and plastic pit liner sitting above the ground, with the cable then proceeding fully exposed down the hill side.  That said, the ground is basically ironstone, and the slope is quite steep, so we totally that understand Telstra didn't want to dig a ditch all the way.

 Here is John, one of the group up on the vantage point. You can see Telstra's big microwave relay tower and electronics cabinet here.  That extra 15m height at each end makes all the difference for being able to get line-of-sight back to the old observatory.

This is the view back towards the old observatory and village.  Neither are visible thanks to the low hill in the middle of the background.

My wife and daughter had a quick game of badminton on the hill top while we came to realise that we would have to run the link down the other side of the range.

 The trail-head map shows the village and Arkaroola Station.  We had been trying to get a link roughly along the Station Backtrack.  Now our attention was turning to the Acacia Ridge, where we knew there was good line of sight, but access would be more difficult, requiring a 1 hour walk up to the ridge line.

Instead of walking up to the ridge, we decided that it would be more fun to give John the chance to setup a temporary link between the two observatories, to get an idea of how to aim the dishes.

Unfortunately some the pole in the handy location was too fat for the mount:

So we attached it to the fence rail instead:

It's a bit tricky to tighten up, but we got there:

A quick visual inspection to see that the dish was more or less aimed in the right direction. We would come back later to trim the direction, only to discover we had it pointed perfectly to begin with.

It was back to the new observatory to pick a mounting point.  Lots of big I-section here, too large to clamp onto.  If you look at the full resolution image you can just make out the dish above the green-roofed building right of centre:

Unloading the gear...

Then applying a bit of bush ingenuity to make a mount that we could attach to:

And a few minutes later we had a nicely aimed dish:

Connect the battery, and aim it up, and obtain a very nice 55dB link margin at 300 mega-bits/second.

Due to the difficult access on the ridge, we didn't have enough time left to actually install the permanent link, although we did spend some time with Marg Sprigg to work out exactly where to mount the hardware at the homestead and village when we head back up in October.

We did however have a little time to enjoy some of the beautiful landscape, the following shot just 50 metres from our accommodation.  The natural history, amazing minerology of Arkaroola is a whole other dimension to explore.

Caleb found a few minutes to chat to the bar staff, and then it was time to head home.