2014-08-05 / Andy Gunn
OTI works with Digital Stewards to construct this year’s conference-wide network.
At the 2014 Allied Media Conference, the Open Technology Institute partnered with the Detroit Digital Stewards to construct the conference-wide mesh network, MagicNet. This network provides a basic wireless connection to the Internet, as well as a platform for local applications and services for conference attendees. In previous years, OTI has led the MagicNet planning and construction as a training exercise for Digital Stewards from both Detroit and Red Hook, Brooklyn. This year, the newest round of Detroit Stewards led the process with minimal assistance from Open Technology Institute staff.
As in previous years, attendees at the Allied Media Conference (AMC) rely on network connectivity to collaborate, take notes during sessions, access materials, upload files, and access social media. The MagicNet has been used in years past to facilitate this, as conference attendees have previously stated that the Wayne State network’s captive portal and login process is cumbersome. The conference was spread over three buildings, less than in prior years - but with a far larger separation between buildings. This led to a different network design and approach from previous MagicNet installations.
Digital Stewards Oscar and Gabriel install a mesh node in an AMC session room.
Network details by the numbers:
- Number of wireless nodes: 11
- Hardware used: Ubiquiti PicoStation M2 and NanoStation M2 units
- Total cost of wireless equipment: $890
- Wireless software version: Commotion version 1.1rc2
- Number of people involved in the construction: 10 (8 Digital Stewards and 2 OTI staff)
- Total number of hours to build and test: 4
- Number of simultaneous network clients: between 50 and 500 per day
- Number of simultaneous connections to a single node: between 6 and 88
This year, the Digital Stewards and OTI were able to use a full release of the Commotion mesh software - version 1.1rc2. While this was still a “release candidate” of the newest software version, it represented the most stable and well tested version of Commotion to date. The conference was a prime opportunity for OTI to test this release candidate in a very high-use and complicated scenario to make sure it was ready for wider public use.
OTI staff Field Engineer Andy Gunn connected with Digital Stewards trainers Diana Nucera and Anderson Walworth of Allied Media Projects before submitting a proposal to build the network at the 2014 AMC. They agreed to collaborate and build the network, with the current 2014 Digital Stewards leading the planning and installation process.
This represented an excellent training opportunity for the second round of Digital Stewards participants - those taught by AMP staff and prior Digital Stewards participants, now acting as instructors. These “next generation” Digital Stewards had just begun building wireless networks in a few neighborhoods on Detroit’s east side, and were eager for more opportunities to learn about installing and configuring Commotion, and using mesh networks in a dense, indoor environment.
A few weeks prior to the conference, OTI shipped a box of equipment to Detroit for use at the conference. The box contained 14 wireless routers, of various makes and models. Most were Ubiquiti PicoStation M2 units, with a few NanoStation M2 units, UniFi Outdoor AP’s, and TP-Link TL-WDR4300’s. The Stewards had previously only worked with PicoStation and NanoStation units - as these have been the most used Commotion development devices - but were able to upgrade and install Commotion on the devices that were new to them. Stewards updated all the devices from OTI to the 1.1RC2 version of Commotion, and configured the list of devices shown in Appendix A.
OTI staff sent along a map suggesting router placement for the conference, which the Digital Stewards used to plan and configure the network equipment. This map is shown below:
Each device was configured using a standard naming convention for the routers, to keep track of where each was to be installed. Similarly, each node was configured with an Access Point name that would identify it to the conference attendees as part of the MagicNet. These names are listed in the equipment list in Appendix A.
On Thursday, the day before the conference began, the Digital Stewards and OTI staff met in McGregor to distribute equipment and install it in the locations shown on the map above. The installations went smoothly, and are described in more detail in the Network Details section below.
As stated earlier, the conference network was primarily to provide Internet access to conference attendees. The OTI was interested in providing access to local applications to further test Commotion’s built-in app portal. Through discussion with Allied Media Projects staff Diana Nucera, it was decided that the following applications would be advertised on the MagicNet:
- The AMC session browser - a link to the online session browser for quick access to session descriptions, times and locations.
- The Really Rad Radio stream - the AMC has hosted a live radio stream as a fun activity and training opportunity for conference attendees.
- MediaGrid chat and file sharing - For additional communication and collaboration opportunities, each network would have a local server providing chat and file sharing capabilities.
To this end, OTI staff Technologist Dan Staples configured two desktop computers with the most recent version of MediaGrid, an open source free software package that hosts a web-based chat and file sharing service. These two computers were previously configured several months before for a local applications training session held for Digital Stewards in Detroit, facilitated by AMP staff Diana Nucera and Anderson Walworth, and OTI staff Georgia Bullen and Dan Staples.
The MediaGrid servers were only lightly used during the conference, but only minimal effort was made to alert conference attendees to the availability of the resource. In future years the local servers could be made central to some functions of the conference or some sessions.
Network Details and Map
As in previous years, the MagicNet spanned multiple buildings - McGregor Conference Center, the Community Arts Auditorium, and Old Main. The AMC had been located in McGregor and the Auditorium many times in prior years, but this was the first time the conference would use Old Main. In addition, Old Main was very physically separate from the other buildings - by a third of a mile, with no line of sight between the buildings.
This created the challenge of setting up two networks, both of which would need to host local applications, as described above. Several possible solutions were discussed, such as using a Virtual Private Network (VPN) to bridge the network, and requesting a special subnet or static route on the Wayne State Network. These were deemed too complicated to complete on a short timeframe; the two networks would not connect, and each would need to have a separate local applications server.
McGregor and the Community Arts Auditorium
The McGregor network was similar to previous years’ MagicNets - a set of omnidirectional wireless mesh nodes, distributed throughout the building. Each was connected to an Ethernet port on the Wayne State local area network, obtained an IP address from that network, and were configured automatically as gateways to the Internet. After all the devices were installed, a well-connected wireless mesh network was established automatically between the devices. It was determined for the best stability and performance of the network to enable the devices to mesh over the Wayne State Ethernet network. The process for enabling this in the Commotion interface was demonstrated by OTI staff, and the devices were configured by the Stewards.
Map of the McGregor and Auditorium network showing mesh nodes and links.
The Auditorium proved to be a small challenge, and was therefore not fully installed until mid-day on the Friday of the conference. The Ethernet port used in previous years to provide a gateway and connection to the other nodes was not active. A request was put into Wayne State information services to enable the port, and the wireless node was then able to mesh over Ethernet with the rest of McGregor. To provide access to the exhibition area outside of the auditorium, an additional mesh node was placed and connected to the Auditorium node wirelessly.
The Old Main network was built in an identical manner to McGregor and the Auditorium network - devices were installed in five rooms, providing wireless coverage through the walls to session rooms nearby. These were plugged into Ethernet ports in nearly every room, and were similarly meshed over the Wayne State Ethernet infrastructure, though the mesh would have functioned adequately with only wireless connections.
Map of the Old Main network showing mesh nodes and links.
The only issue with the network installation in Old Main was an inactive Ethernet port in Room 174. Rather than move the node in the middle of the conference, OTI staff and the Stewards opted to leave it in place, and allow it to mesh wirelessly with it’s nearest neighbor in room 151.
Every MagicNet installation for the Allied Media Conference has proven valuable as a heavy-use testbed for the Commotion software. This year’s network proved no different - two issues were discovered, one of which is currently being resolved, and the other will require further testing to verify.
The first issue involved the combination of wireless and Ethernet mesh connections on a single node. In the case of Old Main 151 and the Auditorium nodes, each was connected to several mesh nodes over Ethernet, and a single node via a wireless link. The nodes on the wireless links could not connect to services elsewhere on the network due to a configuration error in the firewall. The current firewall configuration prevents traffic from wireless mesh nodes to traverse more than one hop over Ethernet, a bug that has been added to the Commotion development issue tracker.
The second issue requires further testing to verify. Initially the wireless node installed in Old Main 151 was a Ubiquiti UniFi outdoor AP unit, which provides 2x2 MIMO - a feature the other PicoStation nodes lack. The node installed in Old Main 174 was a NanoStation M2 unit, which was also 2x2 MIMO. This feature provides a much better connection in indoor or high-interference environments, due to the two wireless streams able to better adapt to these conditions. Unfortunately, the UniFi unit would intermittently lose wireless connectivity. The cause of this is still being determined, with the likely issue falling into the categories of hardware failure or driver incompatibility. An underlying Commotion software issue is unlikely, but being investigated. The former two issues are outside of OTI control, but further testing should determine the actual cause. The UniFi unit was swapped with a PicoStation from McGregor, which was deemed to be redundant since there were two nodes covering a small area.
At previous MagicNet installations, network usage data was not collected, due to both lack of time and the lack of an available tool to gather the data. Last year a set of scripts were written to collect data at the International Summit for Community Wireless Networks in Berlin. OTI Lead Technologist Josh King, attending the AMC this year, ran those scripts on the network and collected the data in the table below. Unfortunately, the scripts were not completed at the Summit in Berlin, and had to be run manually. Due to time constraints and limitations of the scripts, the data collected is incomplete:
|Building||Node||Time||Auth. Clients||Total Clients||Throughput*|
|McGregor||MagicNet-CAA1||1:30 PM||No data||No data||No data|
|2:30 PM||No data||No data||No data|
|MagicNet-MC2H||1:30 PM||49||75||2.34 Mbits/sec|
|2:30 PM||9||17||4.42 Mbits/sec|
|MagicNet-MCLB||1:30 PM||17||28||18.0 Mbits/sec|
|2:30 PM||23||38||10.2 Mbits/sec|
|MagicNet-MCLL||1:30 PM||6||8||No data|
|2:30 PM||6||8||No data|
|Old Main||MagicNet-OM106||3:15 PM||7||12||No data|
|3:32 PM||8||13||No data|
|MagicNet-OM121||3:15 PM||76||66||No data|
|3:32 PM||76||65||No data|
|MagicNet-OM129||3:15 PM||50||88||No data|
|3:32 PM||50||88||No data|
|MagicNet-OM151||3:15 PM||22||46||No data|
|3:32 PM||22||46||No data|
|MagicNet-OM174||3:15 PM||No data||No data||No data|
|3:32 PM||No data||No data||No data|
Throughput is measured to a laptop connected as a wireless client at one point on the network.
One interesting discrepancy can be seen in the number of clients connected to MagicNet-OM121 - or Old Main room 121. In this case, the number of Authorized Clients is higher than the total number of active clients. This could indicate an error in the splash page client tracking script, or that a very large number of clients had been connected previously, and had since disconnected or moved out of range of the wireless node. In a conference setting, where individuals move from room to room frequently, this seems to be the most likely case.
Below are several visualizations of the networks in McGregor and Old Main, to demonstrate the connections on the network. There are duplicate names on the visualization due to the mesh connections on both the wireless interfaces (links with numbers of 1 or higher) and the Ethernet network (links with the number 0.100).
A mesh network visualizer view of the network in the McGregor and Auditorium buildings.
A mesh network visualizer view of the network in the Old Main building.
Digital Stewards “DIY Mesh Networks” Workshop
In addition to constructing the MagicNet, a coalition of Digital Stewards from Detroit and Red Hook Brooklyn coordinated a session at the AMC entitled “DIY Mesh Networks”. OTI staff were pleased to participate and witness this panel which discussed a bit of the history and process of building networks in various neighborhoods in the two cities. The Stewards screened several videos discussing their stories and why community networks were relevant and useful in their neighborhoods. In addition, they led a hands-on activity for session attendees to make their own Ethernet cables. Bulk cable, RJ45 ends, and cable crimping tools were provided - and after a short demonstration attendees were able to walk through the steps and make their own short Ethernet cables.
AMC attendees making Ethernet cables in the DIY Mesh Networks session.
The future of the MagicNet
For the past three years, OTI has participated in the installation of the conference network at the AMC to gather valuable feedback and data on the Commotion software, and provide an excellent opportunity to further train Digital Stewards participants. With the stable release of Commotion 1.1, and a healthy Digital Stewards ecosystem in Detroit and elsewhere, OTI staff now feel that the conference network can be constructed in future years without involvement from OTI. While we at OTI will miss the experience and fun, we are excited to see what changes and improvements others make to the network in the future.
The Open Technology Institute formulates policy and regulatory reforms to support open architectures and open source innovations and facilitates the development and implementation of open technologies and communications networks. OTI promotes affordable, universal, and ubiquitous communications networks through partnerships with communities, researchers, industry, and public interest groups and is committed to maximizing the potentials of innovative open technologies by studying their social and economic impacts – particularly for poor, rural, and other underserved constituencies. OTI provides in-depth, objective research, analysis, and findings for policy decision-makers and the general public.
About Allied Media Projects
Allied Media Projects cultivates media strategies for a more just and creative world. From the intersection of communications, art, technology, education and social justice, we share and develop models for transforming ourselves and our communities. AMP organizes the annual Allied Media Conference. Our local programs innovate media-based practices in education, economic development and community organizing.
The Allied Media Conference is a collaborative laboratory of media-based organizing strategies for transforming our world, held every Summer in Detroit. The AMC is a network of networks – social justice organizers, community technologists, transformative artists, educators, entrepreneurs, and many others – all using media in innovative ways.