Well, it has been a while, but we have been busy with the network. There have been changes at many levels, but the most significant has been the routing protocol used on AREDN networks.
The original protocol, OLSR (Optimized Link State Routing), was designed for mobile ad hoc networks. When AREDN first came about, OLSR was selected and worked quite well while the mesh was small. As the network grew, however, OLSR began to show limitations—it simply was not designed to scale to networks of this size.
A new solution was needed, and the protocol that ultimately won out was BABEL. From Wikipedia:
The Babel Protocol is a robust, loop-avoiding distance-vector routing protocol designed for both wired and wireless networks, including mesh networks, supporting IPv4 and IPv6.
BABEL is now being used to replace OLSR and resolve the issues caused by OLSR’s inability to handle the size AREDN has grown into.
Why the Change Matters: Real-World Examples
As an example, we operate cameras located around the state. In the past, we would occasionally see tearing and loss of video. Below is a screenshot from one of the camera servers.
Prior to the move to BABEL, some cameras experienced tearing and intermittent video loss. Once the backbone was converted to BABEL, those issues disappeared.
Another example is VoIP. The MeshPhone network previously struggled with audio quality and dropouts. Since the transition to BABEL, VoIP calls—as well as DMR repeater links and AllStar nodes transiting the mesh—have been stable, with no dropouts or other artifacts that we now know were caused by the limitations of the old protocol.
Expanding Services on the Mesh
In addition to cameras, we have seen weather stations come online, and we now have three PBXs covering the state. Cities across Oklahoma are building mesh networks and putting them to work. For example, below are images captured by cameras in Duncan, Oklahoma.
This fire was captured from a camera mounted on a 300-foot tower north of Duncan, OK. The fire itself was located on Fort Sill, at least 28 miles away.
This image shows a structure fire just south of the county EOC.
As the incident progressed, the fire grew even larger.
Here is another fire, viewed from the Duncan City EOC.
Fire images courtesy of KD5TDK.
All of these feeds were viewable by anyone on the AREDN mesh using a computer or smartphone.
There are many other services on the mesh, including weather stations.
This is the weather station located at the W5RLW tower site, also known as the South Edmond Node Site.
This is the Stephens County EOC weather station. There are more weather stations on the mesh, but we need more.
We also have repeaters using the network to link into repeater systems. One example is the Oklahoma City North DMR repeater. This link runs entirely over AREDN and is only two hops to the access point into the public network. The long-term goal is to have the back end of these repeaters linked to a local master on the mesh. That way, if the public network goes down, in-state repeaters can continue to function.
We also host a Ham Dashboard, courtesy of WD5G.
AREDN as Infrastructure
There are many services already running, with more on the way. AREDN is a bit like the water and sewer pipes in a building—they operate in the background, quietly doing what needs to be done. Our goal is to make AREDN that same kind of infrastructure for the amateur radio community. We should not have to depend on non-amateur back-end links to connect our devices. We should own not only the building, but the pipes that serve it.
To achieve that, we need to continue building out our infrastructure. We have some good locations to start with in Edmond, but we need to do better. We need to be able to offer a reliable, high-speed data network for our EmComm groups. When they are not using it, we should be using it ourselves—and continually improving it.
The backbones are coming together. The next step is adding sector antennas for end users to connect. The next page shows a view of the Central Oklahoma mesh.
Coverage Maps and Network Topology
Below are coverage maps. KI5VMF wrote the code and runs the server for our network. The first map shows the Oklahoma City metro area.
The green lines represent 5 GHz RF links, while the dotted brown lines are tunnels. Our goal is to move users off tunnels and onto RF links.
The blue dotted lines show connections to the OK Supernode, which facilitates connections to other meshes.
The next map zooms in on our immediate area.
The node just off Edmond Road and west of downtown Edmond is located on the granary. We need to install sector antennas there and build additional node sites. Edmond will likely become the jump-off point for a link north to Guthrie.
The node just west of 33rd and Broadway is the W5RLW tower site, also known as the Edmond South Node Stack. It has been an excellent test site and is fully off-grid, powered by solar. It also functions as the link down to the OKC North DMR repeater. We are fortunate to have a loop via AD5JK and a link to my home site, which currently hosts both the KI5VMF tunnel server and the Supernode server.
In Edmond, we are well positioned to build a very strong network, but more work remains.
Here is a map of Duncan, Oklahoma. Both the county EOC and the city EOC are connected, along with the hospital. The next step there is adding sector antennas so users can connect without relying on tunnels.
The northernmost site is the tower where the Fort Sill fire image was captured.
Statewide and Beyond
The next map shows a full view of Oklahoma. While we have made progress, there is still much to do. Some stations are currently offline but are expected to return.
Here you can see node sites scattered across the state.
Below is a view of North America. You can isolate individual nodes by band or type by clicking the legend.
This view highlights the Supernode network—specialized nodes that allow users on our mesh to connect with users in places like New Zealand or Dallas, Texas, without flooding the local mesh with distant call signs.
If you would like to explore the maps and coverage in more detail, visit: https://oklahoma-supernode.aredn.mcswain.cloud/meshmap/#
I also hope to provide public access to the camera server in the near future, so those feeds can be viewed via the public network as well.
The Bigger Picture
AREDN truly is like the water pipes in a building. It provides connectivity between services using the same protocols and tools as today’s internet, but over RF instead of wires. The goal is to replace wired links with RF wherever possible. The sooner we do that, the better prepared we will be for public network failures.
For those who say that digital amateur radio is not really amateur radio because it transits the internet, this is the answer. Much of the connectivity we need is local.
Wouldn’t it be great to have all of your internet-connected amateur radio tools linked entirely over an amateur radio network?
That is our goal: to provide the RF “pipes” that allow amateur radio devices to exchange data over amateur networks rather than the public internet.
One solution for long-haul links is Starlink. While it is commercial, it has the advantage that if each Supernode uses Starlink, the path between Supernodes runs over Starlink rather than terrestrial networks, which have many potential failure points.
That said, we should also continue working to link neighboring meshes over RF whenever possible. One or two ARDC grants would likely be enough to connect most of the larger towns in the state. We know that low-cost equipment can cover impressive distances with clear line of sight. For example, the link from OKC to Norman is nearly 19 miles and runs reliably using two antennas that cost about $70 each.
This is not an expensive project—but it is a foundational one. It keeps your other networked gear online when the internet goes down.
Chuck, KP4DJT
