Monday, March 16, 2015

Mapping assistance for Vanuatu Cyclone Response

We have had a request from the head of the Disaster Research Centre here at Flinders University asking for volunteers to help re-map Vanuatu following the category 5 cyclone that hit there in the last few days.

Here is the call for assistance:

Dear MicroMappers,

The United Nations has just activated MicroMappers to support their rapid damage assessments in Vanatu following the Category 5 Cyclone. You can accelerate the UN's efforts by donating a few minutes of your time. Simply click here: 

No prior experience necessary. If you can click "Like" on a Facebook picture or video, you can be a Digital Humanitarian.

Thank you!"

Monday, March 2, 2015

OSX Yosemite Printer keeps pausing, and gets stuck on "Ready to print"

If you are printing to a PaperCut server, apparently printing can have trouble from a mac running Yosemite, due to the improved security in CUPS 2.0, which is part of Yosemite.

The interim solution is to relax the sandboxing policy in CUPS 2.0, so that it behaves like it used to.  Of course, it would be better if PaperCut fixed the underlying problem in their software.

The short version of what to do is:

sudo sh -c 'echo "Sandboxing Relaxed" >> /etc/cups/cups-files.conf'
sudo launchctl stop org.cups.cupsd

The long version can be found at:

Sunday, March 1, 2015

MDP, Rhizome, MeshMS and VoMP over Bluetooth

Under a grant from US-AID we are in the process of adding some low-bandwidth transports to the Serval Mesh.  Ultimately, this will hopefully include Wi-Fi Direct service directory, Bluetooth Device Names, as well as using those transports directly.

What Jeremy has achieved so far is to use Bluetooth with an automated peer discovery.  That is, if two phones running Serval Mesh have bluetooth turned on, and at least one of them is marked discoverable, then Serval Mesh on the phones will automatically create a bluetooth serial connection, and start transferring data as though it were another wireless interface, which, after all, it is.

The following photos show Andrew and Jeremy making an authenticated, encrypted VoMP call over Bluetooth:

The in-call latency is probably around 800ms, so quite usable.

And here we have an upside-down MeshMS conversation.  MeshMS messages deliver in just a couple of seconds if there is no other Rhizome traffic.

More posts as we make further progress.

Thursday, January 22, 2015

Mac OSX "Hold for authentication" when trying to print

Today I tried to get printing to work from my mac (running Yosemite) to the printers here at work.  The printers are accessed using SMB.

I could easily add the printers, but when I tried to print, it would accept my username and password for the printer, but then revert straight back to saying "Hold for authentication".

Deleting the printers and recreating them didn't fix it.
Nor did deleting the associated entries from the OSX keyring help.

Thus the usually recommended steps failed to fix the problem.

It took a couple of hours of research and experimentation to discover that this page had most of the information needed to solve the problem.

The problem in my case was caused by the print system on the mac from failing to properly negotiate authentication in some way. But here is how I fixed it:

Step 1: Try to print something to this printer.  Then open the print queue for the printer, and click on the refresh (curly-arrow) icon to the right of the job name.  It should prompt you for your username and password for the print server, and then revert to "Hold for authentication".

This is really important. If you don't try to send a print job and have it stuck in "Hold for authentication" first, strange things can still happen after following the procedure below.  For me, I found that the print job would try to print, but the print queue would then immediately become paused, with the print job marked "Ready to print".  Very frustrating.

Step 2: Open a terminal window.  Everything we do from here will be done from in the terminal window.

Step 3: Find out the name of the printer on the command line by typing the following and pressing return:

lpstat -s

Step 4: Find the printer in question in the output. You will see that the names of the print queues have any fancy characters replaced with an underscore.  So your print queue name might have lots of underscores in it.  For example, my printer called "Tonsley : mono" appears in the output of lpstat -s below as "Tonsley___mono" (highlighted below):

$ lpstat -s
system default destination: Tonsley___colour__A3_in_tray_2_
device for GenericScanner: usb://00000000-0000-0000-FA13-000000000000
device for LaserJet_6MP__Jet_Direct_: socket://
device for Lexmark_6200_Series: usb://Lexmark/6200%20Series?serial=21B1280030008E5
device for Loopback: socket://
device for Samsung_CLP_310_Series: usb://Samsung/CLP-310%20Series?serial=149RBAFZ400869Z
device for Samsung_CLP_315_Series___alfred: dnssd://Samsung%20CLP-315%20Series%20%40%20alfred._ipp._tcp.local.
device for Samsung_ML_1640_Series: usb://Samsung/ML-1640%20Series?serial=3511BAFS501610N.
device for Tonsley___colour__A3_in_tray_2_: smb://

device for Tonsley___mono: smb://

Step 5: Force the mac to use username,password authentication for this printer by typing the following command (but don't forget to change the printer name from Tonsley___mono to the name of your print queue that you obtained in the previous step).  

sudo lpadmin -p Tonlsey___mono -o auth-info-required=username,password

When you hit return after typing this command you will be asked for your mac password.  Type it in.

Step 6: Attempt to print using the printer.  It should now work.  If it doesn't try deleting the printer and following the sequence again.  If the print queue keeps pausing itself and saying the print job is "ready to print", read the important note on step 1.

If this information helps you, please consider donating to

Sunday, January 18, 2015

Bleeding Edge Mesh Extender kits finally ready for shipping

It has taken us much longer than we had hoped, but we finally have the Mesh Extender kits ready to post out to our generous supporters from our Indiegogo campaign.  As a token of appreciation to our long suffering supporters, we have included a pair of Serval test phones into the kits so that everything they need is there and setup for when it arrives.  Here is the contents of each kit:

I took a couple of shots during the testing of the last pair I packed this morning here at the University's new building at the Tonsley site.  Here is a Mesh Extender and test phone up on our 4th floor lab:

Then took another down to the ground floor to make sure the UHF radios still had link:

Finally, all the units were packed.  Once I have reconfirmed everyone's postal address, we will send these out.

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;