Category Archives: Technology

Articles about general technology – illustrative but not necessarily about farm networking.

An interesting new company – gThrive

ppt logogThrive is one of the companies I have been watching for a while, because I thought their technology was interesting. I think that the use of sensors for monitoring soil conditions is an excellent example of what technology can do for agriculture, but the existing solutions out there are simply too expensive for use outside of very high-value crops.

OnegStake_STK-51615-001gThrive took the approach of using modern sensor and microprocessor technology and mating it with low-cost packaging to create a new soil sensor with more “intelligence” at lower cost than anything currently available on the market – hundreds of dollars per probe instead of thousands of dollars, with more sensors on the probe than had previously been possible.

The probes are simply plastic stakes, each of which has several sensors, a low-power CPU, a battery, and a low-power data radio, which communicates with their gLink base station. The gLink base station must be connected to the Internet via either a cellular connection or WiFi. This means, of course, that it can be easily added to your AyrMesh network, allowing you to have soil probes in multiple fields without having to rack up massive cellular data bills.gThrive_CustomInstallation-001

All data from the stakes are uploaded through the network to gThrive’s web site, which you can access from anywhere with any Internet-connected device. It’s a simple, clean, efficient system, and they have just started selling their system at the recent World Ag Expo.

Seeing products like this come to market validates the reason we started the AyrMesh product line – to help farmers get more data, faster and cheaper, and be able to do more on the farm. Products like this can dramatically add to the value of your AyrMesh Wireless Farm Network, and vice-versa. We wish gThrive all the best and look forward to working with them and other companies bringing new network-connected products to the ag market.gThriveKit_ACPowered-001

(All pictures courtesy of gThrive)

Long Range WiFi: two approaches

AyrMesh HubWe didn’t invent the idea of putting WiFi on farms and ranches, although I think we’ve done a lot to popularize it. And it’s not really WiFi that’s important, it’s just having a farmwide network that you can connect to and move data with.

When we started, we realized there were two ways we could build out the farm wireless network, and that we’d need to support both ways. However, we had to start somewhere, and we knew that the best short-term “proof of concept” was using the mesh network approach: a bunch of high-power WiFi Access Points that are connected to the Internet and talk to each other using a meshing protocol. That’s what gave rise to the AyrMesh Hub.

Because the Hubs can be up to 2.5 miles apart, it allows you to extend your network out quite a ways from your home place, and that’s useful for a lot of people. It also allows you to “get in the game” for a minimal investment – a few hundred bucks for a Hub and a little time putting it up high and out in the clear gets you WiFi across your farmyard and out into your fields. Then you can extend the network from there with additional Hubs.

However, sometimes you just want to connect someplace into your network, and you don’t need to have WiFi. For those cases, a different approach is optimal: point-to-point microwave links, also known as “bridges.”

AyrMesh BridgeA bridge can use WiFi or a WiFi-like signal to connect two locations and pass data between them. Typically they are “Layer 2” devices, meaning that they work just like a long, wireless Ethernet cable. You plug one radio into your network (typically your router) and then plug the other radio into whatever you want to put on your network (a computer, IP camera, WiFi access point, etc.), and everything works just like it was plugged into your router.

The AyrMesh Bridge uses microwave radios that use the 5.8 GHz. band (used for 802.11 WiFi “a,” “dual-band n,” and “ac”), but they use a special “narrow-band” microwave signal that increases the range, reduces the effects of interference, and makes the signal invisible to WiFi “sniffers.”

Of course, if you are just connecting some distant device or devices into your network, you can also use an AyrMesh Hub and an AyrMesh Receiver. It will actually work the same way; the differences are:

  • The AyrMesh Bridge is just a wireless Ethernet cable that doesn’t provide a wireless signal usable by anything else. The AyrMesh Hub provides WiFi that other devices can use.
  • The AyrMesh Bridge is a “1-to-1” system, but you can have several Receivers talking to one Hub.
  • The Receiver can be up to 2 miles from the Hub, but the Bridge radios can be up to 5 miles apart.

It’s not necessarily an “either/or” thing. Several AyrMesh users are using the AyrMesh Bridge to reposition their Gateway Hub to the top of large structures (e.g. grain legs) to give the Hubs maximum range. A couple of people are using their Hubs for WiFi but providing connectivity to other buildings using Bridges (with the Hub and the Bridge radio mounted next to each other on top of the house or office). And you can use a Bridge connected to a Remote Hub to connect a device several miles away from the Hub.

There are a lot of folks out there selling wireless bridges – we think the AyrMesh Bridge is the best for one important reason: it’s the easiest to set up and use. No configuration is needed: you just connect both radios in the Bridge to your router. They download your configuration from and then all you have to do is mount them outside pointing at each other.

IP Cameras on the Farm: Part 3 – Using IP cameras for security


QNAP NVR, courtesy of QNAP

Now you know how to select an IP Camera, set it up on your farm, and view it from wherever you are, on or off the farm, which may give you a greater sense of security by itself.

However, you can’t watch what’s going on 24×7, and, with most cameras, you can’t go back and see what happened a couple of minutes ago (or last week). If you want to incorporate cameras as part of a security system (which may also include things like driveway sensors, indoor motion sensors, window/door open sensors, and other devices), then you should, at a minimum have some sort of recording, and probably some sort of motion detection on the cameras. What I have found to be best is some sort of system that is continuously monitoring the cameras, and, when motion is detected, it records the previous several seconds of video and keeps recording until after the motion stops. That way, I find, I get a nice, clear video of the mailman coming up to the box every single day (and, if I choose, a text and/or email with a picture of the mailman within a few seconds of his arrival).

But, seriously, if you are having trouble with intruders (people breaking into your storage sheds or stealing Anhydrous), getting notification and pictures of them is a good idea. For that, you need a Network Video Recorder (NVR). An NVR is a device that plugs into your network and monitors your IP cameras, allowing you to view several cameras at once and go back to see what happened at a particular time. Most modern NVR systems also have motion detection and multiple alarm functions (including email and tripping a relay to set off an alarm).

Swann DVR with cameras, courtesy of Swann

Swann DVR with cameras, courtesy of Swann

An NVR is different from a Digital Video Recorder (DVR), although both can be useful tools for farm security. A DVR typically has a number of coaxial inputs for cameras, so you can attach 4, 8, or 16 cameras to the unit using coaxial cable and it will continuously record the video from those cameras. Most modern DVRs also have an Ethernet port so you can connect them to your network and monitor the cameras from wherever you are. A DVR can be very useful anywhere you want several cameras in a single physical location, like your home, workshop, or storage shed, where you don’t mind stringing wires. Most newer DVRs can also detect motion send you an email or other form of alarm when they do.

Foscam indoor camera with storage - the little microSD slot under the antenna - courtesy of Foscam

Foscam indoor camera with storage – the little microSD slot under the antenna – courtesy of Foscam

Some newer IP cameras even have the NVR capability built-in, usually via an SD card slot. They store either still images or video to the SD card continuously so you can just “back up” while you’re viewing the cameras.

Almost all IP cameras have some form of motion detection, but many of them are effectively useless. There are three types of motion detection:

  1. Overall picture motion detection – this just looks for the number of pixels changing in the frame and alerts if that number rises above a certain level. Unfortunately, this is almost entirely useless, because, if the sensitivity is high, it will “alarm” every time the lighting changes slightly, and if the sensitivity is set too low, it won’t alarm at all.
  2. Setting a "zone" so the camera will alarm when the door is opened - courtesy of

    Setting a “zone” so the camera will alarm when the door is opened – courtesy of

    “Zoning” motion detection – this allows you to put rectangles into the camera’s frame and only alarm if there are changes inside those rectangles. This works better, but you still get a lot of “false alarms.”

    Object detection, courtesy of Sitehound

    Object detection, courtesy of Sitehound

  3. Object detection – this is an algorithm that can pick out moving objects in the video stream and distinguish them from changes in the background. This means that you only get an alarm when something moves, and you can set the size of the object that will set an alarm so you don’t get called every time a gnat flies by.

Most inexpensive cameras use the first type of motion detection, which means the on-camera detection is worthless. Almost all other cameras use the second type of detection, which is not useless but still not great. Some high-end cameras can do object detection, but they’re pretty expensive.

The better idea is to have your NVR software do the detection and alarming, rather than the camera. There are two ways to do this: using a dedicated NVR (a small computer running embedded NVR software) or running an NVR program on a desktop computer that’s on 24×7. There are advantages to either approach.

Using a dedicated NVR is simple: you set it up, add the cameras to it through the onboard user interface, and forward a port to it on your router so you can access it while you’re away. QNAP is a vendor that makes a large range of standalone NVRs that are compatible with a wide variety of cameras. In all honesty, I have never been able to evaluate one, but customers have reported good results with them. Synology has developed a pretty good reputations, also – both brands are generally available on Amazon.

The downside to the dedicated NVR is that only some cameras are supported (although the brands mentioned above support a huge number of brands) and that it is difficult to evaluate the software to tell how well it will work for you. The vendors don’t really provide much detail about how they detect motion, what options are available, and what the units can do.

Ubiquiti Cameras and NVR, courtesy of Ubiquiti Networks

Ubiquiti Cameras and NVR, courtesy of Ubiquiti Networks

Some camera vendors like VivotekGeoVision, and Ubiquiti sell both cameras and NVRs to work with their cameras in an integrated package. Going that way makes it easier to know your cameras will work the the NVR, but more difficult to evaluate whether you have the right cameras and NVR for your operation.

The other option for an NVR is to use an NVR program on a computer that’s running all the time. There are several of these programs, but the two most popular are BlueIris and SightHound.  BlueIris is less expensive and runs on any Windows PC; SightHound is more expensive, but has a number of important advantages:

  1. It runs on either Windows or Mac computers;
  2. it is very easy to install, configure, and use; and
  3. it features an advanced object-detection motion detection.

I’m an unabashed fan of SightHound – I have written about it before on this blog – although I have used BlueIris and it is also very good. I also like the Ubiquiti system (Note: Ubiquiti builds the hardware for the AyrMesh system), although I find their software to be a bit too complex for most users. It also integrates with their mFi sensors and switches for security and automation.

Dropcam - courtesy of Dropcam

Dropcam – courtesy of Dropcam

There is actually a third option – a camera that automatically loads its video to a “cloud-based” NVR. Dropcam is a system that uses nice, small, relatively inexpensive indoor cameras, which automatically send their video stream to their cloud servers, without the need for port-forwarding. I have also written about Dropcam before on this blog. The big advantages with Dropcam is that they are VERY easy to set up and use, and the company is now part of Nest (maker of the Nest thermostat), which is part of Google – they have the resources to keep this going and expand those products to do a lot more in the future. The disadvantages are:

  1. They currently only make indoor cameras; there is no outdoor option, and the cameras are not designed for outdoor temperatures.
  2. They charge on a per-camera basis for the recording function. They charge $10 per month/ $99 per year for the first camera and $5 per month/ $50 per year for each additional camera (that’s for 7 days of recording; they charges for 30 days of recording are 3x higher)
  3. There is no way to directly view the camera – the only way to view it is through the Dropcam website. This is not a big problem practically, but it does bug me a little. Even without a subscription, you can view the camera through their website and get notices when motion is detected, which is nice.

Whatever cameras and NVRs you choose, you’ll need to connect the cameras to the network, connect the NVR to the network, and make sure the NVR is “talking” to the cameras. You can then port-forward to the NVR (remember about this from the router series?) in order to access it from the Internet; that way you don’t have to port-forward to each of the individual cameras. You’ll need to fine-tune the sensitivity of each camera in order to get appropriate “alarms” for movement. You’ll also need to set the alarms up so they contact you appropriately. Setting up an email alarm is relatively easy, and all the cellular phone providers give you an email address that goes through as an SMS text message – for instance, on Verizon, if the phone number is 555-123-4567, you can email “[email protected]” That way you can get a text message on your phone whenever motion is detected.

So, now you have cameras set up in the critical parts of your farm, which you can view through your NVR, and you are set up to get alerts any time something moves in the field of view of those cameras. All of this, of course, is made possible because of your AyrMesh Network, covering your farm with powerful IP connectivity.

And there’s still a lot more you can do with the network… stay tuned!

IP Cameras on the Farm: Part 1

Security_camMany people start building an AyrMesh network on their property to provide Internet access across their acreage. However, having an Internet Protocol (IP) network across your property gives you the opportunity to connect devices on the property to help you be more productive, more efficient, safer, and happier.

When I ask people what else they’d like to do with their AyrMesh Network, the first thing that usually comes up is cameras – the ability to see their property remotely.

There are two distinct reasons for putting cameras on your property: the first is what I call “situational awareness” – being able to bring up a view of some part of your farm any time you want. The second is for security – automatically monitoring some view of your property and alerting you when something happens.

pigletsIf you have animals on the farm, you probably worry about them – especially if your livelihood is tied up in them. One of the most common uses for cameras on the farm is to be able to check on the animals, whether it’s just so the kids can see the horses when you’re away or if you need to check on farrowing sows, calving cows, or foaling mares to protect your investment.

drivewayA lot of people also just want to be able to view some part of the property, like the driveway or the kid’s play area, so they can know what’s going on any time. Sometimes these cameras may be dual-purpose, serving both a security function and for situational awareness.

tablet-with-drivewayPutting a camera on your property gives you a “view” – you get the IP address of the camera from your router and you can bring up that view from anywhere on your property. Then you can do what’s called a “port forward” on your router to make your camera viewable from the Internet, wherever you may be. For instance, I always forward port 9001 to a camera in my living room. I can look at my public IP address on and find that it’s (it’s not, but let’s pretend…), so I just need to point a browser to and log into my camera (note: you HAVE to have a good, strong password on your camera).

Next we’ll talk a little about the different kinds of IP cameras and the tradeoffs and compromises you can make – see part 2 here.

WiFi standards – 802.11a to 802.11z

WiFi routersIt seems like every time you look around there’s a new crop of WiFi routers offering unbelievable speeds and ranges due to the use of a new WiFi standard. Years ago, WiFi started out with 802.11a (back in the last millenium) and then 802.11b, which gave way to 802.11g, which was replaced by 802.11n, and new routers use 802.11ac. And, if you’re wondering, yes, of course there’s a new one on the way, currently called “802.11ax.”

There are also many ancillary standards associated with these, even an 802.11z standard (having to do with extensions to Direct Link Setup, whatever that means). The “a,” “b,” and, to some degree, “g” standards are, for all intents and purposes, obsolete, because nobody has built equipment using those standards for a long time. On the other hand, all the standards are “backwards-compatible,” so the newest equipment can still interoperate with the oldest “a” and “b” equipment.

For us here in the Ayrstone labs, the amusing thing about all these advancements since 802.11g in 2003 is that they are squarely centered on one thing: improving indoor WiFi performance. The reason that amuses us, of course, is that it’s exactly the opposite of what we’re trying to do, improve outdoor WiFi performance. There has been almost nothing done to improve outdoor long-distance WiFi since the 802.11g standard.

Here’s a quick rundown of the various WiFi standards:

  • 802.11 – 1997 – up to 2 Mbps on 2.4 GHz and InfraRed with WEP encryption
  • 802.11a – 1999 – up to 54 Mbps on 5 GHz
  • 802.11b – 1999 – up to 11 Mbps on 2.4 GHz
  • 802.11g – 2003 – up to 54 Mbps on 2.4 GHz, WPA/TKIP encryption
  • 802.11n – 2009 – up to 600 Mbps using both 5 Ghz and 2.4 GHz, MIMO, WPA2/AES-CCMP encryption, wide channels
  • 802.11ac – 2013 – over 1 Gbps using both 5 GHz and 2.4 GHz and extra-wide channels, MU-MIMO

802.11g was the standard that made WiFi useful (effective data rates of over 20 Mbps) and safe. The original WEP encryption standard in 802.11b was fatally flawed and easily broken – we now consider it “anti-security,” because it gives the uninitiated the illusion of security but does not actually deliver any, much like having a door made of paper painted to look like steel. WPA/TKIP encryption is still considered unbreakable (when used with strong passwords), so 802.11g WiFi devices are still perfectly useful.

802.11n added even more unbreakable security (WPA2/AES-CCMP), which is designed for large networks and organizations. It also added MIMO (Multiple Input, Multiple Output), a way of using multiple antennae to increase the bandwidth and increase the range of the WiFi signal, especially indoors. A single antenna senses “multipath” (signals bouncing off the walls and other solid objects) as noise, because they are slightly out of synchronization with signals coming directly from the other station. MIMO antennas can “correct” and re-synchronize those multipath signals, improving indoor performance dramatically in some cases. 802.11n also introduced dual-band capability, using both the 2.4 GHz and 5.8 GHz bands to increase throughput, and “wide” channels – increasing the amount of electromagnetic spectrum used from 20 MHz per channel to 40 MHz. Wide channels increase bandwidth, but at the sacrifice of range. So you can get faster data speeds close to the WiFi Access Point, but speeds will drop off quickly as you move away.

802.11ac is the latest standard, and it adds on top of 802.11n. Specifically, it allows for extra-wide channels (80 or even 160 MHz in the 5 GHz band) and MIMO improvements. In particular, it adds “MU-MIMO” or Multiple-User MIMO to expand the advantages of MIMO to multiple users of a WiFi access point, as well as increasing the number of spatial streams (from 4 to 8) and offering improved modulation techniques on the wider channels (256-QAM).

So the improvements to WiFi since 2003 can be roughly broken down into 3 areas:

  1. 5 GHz – The higher the frequency of a radio signal, the more it behaves like light, so the more it is affected by solid objects. 5 GHz. signals disperse more in air, and pass through solids even more poorly than 2.4 GHz. signals (which don’t do very well). So, with some notable exceptions (very focused point-to-point links with very clear line-of-sight), 5 GHz is only useful indoors and for very short distances.
  2. MIMO – MIMO is one of the most exciting improvements to WiFi, because it can dramatically improve indoor performance. Of course, both the access point (e.g. wireless router) and the client device (e.g. laptop) have to have MIMO to make the best use of it, but can really improve both range and throughput indoors. Outdoors, however, where there aren’t walls that signals can bounce off of, the value of MIMO is very limited.
  3. Wide channels – I sometimes explain that radio signals are a lot like plumbing. If you have a water hose with a constant pressure, you can put a narrow nozzle on it and push a little water a long ways, or you can put a wide nozzle on it and push a lot of water a little ways. Wide channels are like a wider nozzle: more bandwidth that doesn’t travel as far.

The key to getting maximum range outdoors is to “squeeze” the stream down as much as possible to force it out toward the horizon. The AyrMesh Hubs do this by going somewhat against the “trend” in WiFi:

  1. 2.4 GHz only – for lower dispersion and best penetration of solid objects
  2. SISO – focusing the radio signal (the spectral density) into a single beam for maximum range
  3. Narrow channels – focusing the radio signal into the smallest channel width for maximum range

When we introduced the AyrMesh Hub2n, we noted that it uses 802.11n technology. However, while it does comply with the 802.11n standard, it is, essentially, using the 802.11g features present in 802.11n and almost nothing unique to the 802.11n standard.

That’s not to say that we’re not keeping close tabs on the improvements to WiFi and trying to figure out ways to improve our products. By moving to 802.11n, we picked up WPA2/AES-CCMP encryption, which is actually more efficient on many WiFi radios equipped with hardware encryption, and new modulation methods which may provide marginally better performance. Right now we don’t see any improvements from MIMO, for instance, but we may yet find a way to make use of it. We also have hope that new, more efficient modulation methods could provide us new ways to increase the range and throughput of outdoor WiFi.

We also made use of another WiFi standard in the Hub2n: 802.11s, the new WiFi meshing standard. Time will tell, of course, but we hope that adopting this standard will enable us to introduce new Hub models and other equipment without changing the meshing, effectively “future-proofing” the Hubs.

What this means is that now is the perfect time to build your Wireless Farm Network using WiFi: the technology is extremely well-proven, inexpensive, and reliable. There are lots of contenders to take the place of WiFi for outdoor connectivity, from Super-High-Frequency radio to “White Space” radios (using the unused frequencies in the Television band). None of them are going to offer anything close to the price/performance you can get today out of outdoor WiFi, at least for a very long time. So you can build your network well-assured that there isn’t something waiting in the wings to make your investment obsolete. There will never be a better time to build out your Wireless Farm Network.

Getting the most out of your router – part 2


The ASUS RT-N66U – a modern, high-end home wireless router

In the last article in this series, I discussed what a home router is and a little bit about how it works, as well as providing guidance on how to set up the DHCP server.

IP addresses on your LAN are assigned one of two ways: either by the router’s DHCP server, which provides them out of the DHCP address pool (which I suggested should be to or by statically assigning them yourself (which I suggested should be out of the remaining to addresses). Assigning static addresses is very seldom necessary on modern routers, however, because most modern routers have a feature called “DHCP Reservations.” This allows you to specify the MAC address of a device and make sure it is assigned the exact same address via DHCP every time it is connected to the router. Using DHCP reservations, you can ensure that your laptop always gets the same IP address without having to configure a static address for it (which is a pain, since you’d have to re-configure it every time you go to the coffee shop).

Using either static addressing or DHCP reservations, you may want to make sure that “infrastructure” on your home network, like file servers, entertainment systems, or security devices always have the same IP address.

Your router’s NAT usually automatically closes off all the ports on your public IP address, making it impossible to access anything on your LAN from the Internet. In most cases, that’s a good thing – you don’t want the Internet able to reach your private network. But, in some cases, you want to make devices on your network available from the Internet (ALWAYS protected with strong passwords, of course!). The classic example is the IP camera set to watch something important on the farm – it could be the front drive, livestock, or your machine shed – you want to be able to access it from wherever you are so you can check up on it. But you might also want to be able to check and operate machinery like your grain dryer, pumps, irrigation systems, HVAC systems, etc. from a distance.


The IP camera has a webserver that uses port 80 (usually) for its interface, so the trick of port forwarding is to open one port on your public IP address and tell your router to “forward” all packets coming to that port automatically to port 80 (or whatever port you configure) on the camera. So you “knock a brick” out of the router’s firewall by specifying one port on the public side (I like to use ports 7001-7099, because very few services use these ports) and forward that public port to a port on your camera.


The way you do this varies from router to router, but the drill usually entails going to the “port forwarding” interface on your router and specifying the incoming or public port (7001), the device that’s receiving the packets (your camera’s IP address – 192.169.1.something), and the port on the device that will receive the packets (port 80). Then, if your public IP address is, you can access your camera on the Internet at (the IP address, a colon, and the port number). Some routers allow you to specify only certain incoming IP addresses that can access the camera, but that’s usually not a good idea because, for instance, if you want to look at the camera from your smartphone, you won’t know the IP address of the smartphone.

NOTE: some routers (stupidly, in my opinion) require that the port numbers on the public side and the private side be the same – they won’t forward port 7001 on the public side to port 80 on your camera. If you have a router like that, you’ll need to reconfigure your camera (or whatever device you have) to the appropriate port (e.g. 7001) port before you can do the port forward. You shouldn’t forward ports under 1024 unless you know exactly what you’re doing, because you might be disabling something your router needs to function properly. Forwarding extremely popular ports like 80, 20, 21, 22, 23, 25, etc. can also attract password crackers and other undesirable elements to your network.

Let me emphasize at this point the importance of a strong password on anything that’s exposed to the Internet – if you can access it, so can anyone else, so make sure it’s locked down.

On my own home network, I have several ports forwarded to different IP cameras around my property, as well as ports forwarded to my desktop Windows machine (using VNC so I can access it easily when I’m away) and my Linux development machine (using SSH). I can actually access any of those devices using my smartphone, so I can stay on top of things anywhere I have an Internet connection.

Click here to go to Part 3

Getting the most out of your router – part 1


The venerable Linksys WRT54G – Courtesy of Linksys

The world of networking is complex, including that little bundle of technology sitting on your shelf – your router. It is actually a pretty amazing little device that can probably do more than you realize. In truth, the typical “consumer” router is a combination of three devices:

  1. A router – a router is a device with two or more ports that is used to connect two or more networks together. Typically, the consumer router has a “WAN” port that connects to the “Wide Area Network” of your Internet Service provider and “LAN” ports for your Local Area Network.
  2. An Ethernet switch – you may have noticed that your router doesn’t have two ports; most actually have five: one WAN port and four LAN ports. Inside the box is an Ethernet switch that turns the LAN port of the router into 4 LAN ports to which you can connect wired computers, servers, and even additional Ethernet switches if needed. Actually, it’s 5 LAN ports, because the fifth one is connected to…
  3. A WiFi Access Point – this is simply a wireless radio connected to an internal LAN port that provides a WiFi signal for computers, tablets, smartphones, IP cameras, entertainment systems, and all kinds of other things. This WiFi radio is usually optimized for short-range, indoor use, providing maximum throughput for a short distance.

One of the odd and important facts about a router is that it has two Internet Protocol (IP) addresses: one on the network to which its WAN port is connected (which should be a public IP address, visible from the Internet – e.g.,’s address), and one on the LAN port, the network it creates for you (a private address, not usable from the Internet, e.g. Its job is to take data packets from each network and move them to their destination network. So, if your computer is at on the LAN, and it receives a packet on its WAN port destined for, it passes it to the LAN port where it finds its way to your computer. Similarly, if your computer creates a connection to, the router receives packets from your computer on its LAN port and routes them to the WAN port. When you print to your networked printer (at, say,, it receives packets from your computer and then just turns them around and sends them back down the LAN port, since they are not destined for the Internet.

The ability of the router to accept traffic on a single public IP address and enable several different computers at private IP addresses to have separate “conversations” with the Internet is called “Network Address Translation” or NAT. The way it does this is by using “ports” – simply numbers associated with every IP address.

Each IP address has 65,535 possible ports. Some ports have pre-assigned purposes, some are available for use by applications, and some are ephemeral – here’s a good explanation of which are which. NAT uses those ephemeral ports to keep the conversations between your network and the Internet straight; for instance, your computer’s conversation with this website might be using your public IP address’s port 55135, while another computer on your network might be having a conversation with another website on port 61234. To the two websites, it looks like the traffic is coming from a single computer, specifically your router. Your router then routes the responses from the websites to the correct computer based on the port on which the data comes in.

The private IP addresses on your network are usually assigned by your router using Dynamic Host Configuration Protocol or DHCP. When a computer connects to your network, it will ask the router for an address via DHCP, and the router will provide it one (assuming it has one to provide). The address is referred to as a “lease,” because it will expire at some point after the device leaves the network, so it can be used by another device. However, note that you can simply assign a static IP address to a device in your network, as long as (1) it is an IP address inside your network (usually meaning it has the same three first numbers as everything else on your local network, e.g. 192.168.1.x) and (2) it does not interfere with the DHCP settings on your router (if your DHCP server begins at and your router is at, use static addresses between and, and KEEP TRACK OF THEM WHEN YOU ASSIGN THEM!!!)

The first tip for getting the most out of your router is this: set up your router’s DHCP server carefully. I suggest setting your router’s IP address as and setting your router’s DHCP range from to (204 addresses). The reason for this particular range is that, first, it allows for a large number of devices to automatically use your router, getting private IP addresses via DHCP (204) but still leaves you 48 addresses you can use for devices you want to statically assign. This gives you the flexibility to maintain, expand, and control your home network.

Click here to go to part 2

Myths about Wireless Farm Networking


Myths are fun, but this guy won’t help you get the work done.

We have been talking about the myths of Wireless Farm Networking lately, and I wanted to add my own two cents worth here.

The article about the myths is excellent and stands on its own – I strongly suggest you read it. I thought I’d add a little about the topic here, by focusing on three aspects: Wireless, Farm, and Networking.

Wireless – I have seen “wired” farm networks – a number of livestock producers have trenched and buried fiber lines to their livestock buildings (Ethernet can only go 100 yards) for monitoring and control. However, it’s much cheaper now to go wireless, and it gives you much more flexibility. To build a good wireless network on your farm, you have to learn about “line of sight” (or, more correctly, Fresnel Zones) and position equipment so it has both power available and good radio signal from the rest of the network. It used to be that having a private wireless network across your farm was either technically impossible or cost-prohibitive, but we are proving that wrong every day.

Farm – A farm is pretty much defined as being in a rural area, and we’ve all seen that what works in town doesn’t necessarily work on the Farm, and vice-versa. The AyrMesh network is designed for farm use – relatively few people and machines spread out over a relatively large area. There are lots of good solutions for networking in town, where there are a lot of people in a small area, but they will never work as well as a solution designed specifically for the farm.

Network – The Internet Protocol (IP) network is the single, unified data communications medium for this century. I have seen farms that had a wireless link for their weather station, another wireless link for their GPS corrections, a home WiFI system and cellular coverage. Getting rid of the “point-to-point” solutions and putting everything on the network enables you to collect and transmit the data you need more easily, deliver what you need over the Internet, and gives you the option of adding new technologies to your operation quickly and easily.

Some people think this is revolutionary, but I would argue nothing could be further from the truth: this is the result of a clear evolution over time. In the 1970s academicians started tying computers together and transferring data over the first networks. In the 1980s networks came out of academia and started being used for business and even personal purposes; in the meantime, ham radio operators and researchers were starting to send digital data over radio waves. In the 1990s companies started to network their offices to share files and printers, as well as sending emails. Building-to-building microwave links became relatively common, and Industrial Automation moved to IP networks. In the 2000s the consumer internet became a reality, as did WiFi for wireless data, and we all got “on the net.” Now, in the 2010s, we have the Internet of Things and the low cost of high-power wireless networking, making this the decade of Wireless Farm Networking. The ability to monitor farm data and even control farm operations using a local network connected to the global internet will change agriculture forever.

Unmanned Aerial Vehicles (“Drones”) and Wireless Farm Networks

OctocopterOne of the hottest topics in “Ag Tech” at the moment is Unmanned Aerial Vehicles (UAVs, also known as drones) and the role they can play for the farmer. Drones are hot right now, in Ag and other industries, because technology has made them much more adaptable and much lower in cost.

The possible benefits are tantalizing: an automatic, self-flying platform that can loft things into the air, take them where you need them, and take actions you prescribe. Just a few of the things drones can conceivably do for you:

  1. Take visible-light, near-infrared, and infrared photographs of all your fields at much higher resolution and in less time than satellite
  2. Get instant thermocline and other weather data (pop up 1000′ and check the temperature, wind speed, barometric pressure, etc.)
  3. “Run and get it” service for small items (see the beer drone and Amazon Prime Air)

When I was at the World Ag Expo a few weeks ago, there were several companies showing off drones and talking about drone-based ag services. Please make note of the distinction between drones and drone-based services, because, at the moment, it’s important. Or maybe not. I’ll explain as well as possible.

The Federal Aviation Administration has had a long-standing rule against the use of UAVs for “commercial purposes” – anything involving making money. Now, you can buy model airplanes with very sophisticated self-flying and video systems for fun or research, but not for any money-making purpose. However, a number of people couldn’t help themselves in making use of these amazing machines to enhance their businesses, and they have been getting “cease and desist” letters from the FAA. One guy named Raphael Pirker actually was fined by the FAA, giving him the opportunity to challenge the fine. He appealed to the National Transit Safety Board, and the administrative judge there ruled that the FAA did not have in place any actual regulations for the use of UAVs in non-navigable airspace, and therefore could not enforce the fine against Pirker. There’s a good article about this in Scientific American.

So, apparently, one currently can use UAVs for commercial pursuits, with some (not entirely clear) limitations. I’ll bet if you take your drone anywhere near a commercial airfield, for instance, you’ll get to meet some members of law enforcement and spend time with them. I’ll bet if you take your drone near any government installation, you will get to spend a serious amount of time with members of law enforcement and/or the military. In either case I’ll wager you’ll get to contribute a good amount of money to the government. And there are undoubtedly some private citizens who will happily shotgun your UAV out of the sky on sight.

I’ll also wager that the FAA (or some other part of the government) will create some rules about UAVs to protect people from stuff falling out of the sky on top of people and property, and having our neighbors peeking in 2nd (or 102nd)-story windows. But, for the moment, it looks like the skies are open, particularly out in the rural areas, and I expect farmers to be the first to benefit from UAVs. Some people like Chad Colby are already talking publicly about the opportunities.

Honestly, I think the current “state of the art” is mostly a plaything: the drones that are currently available are mostly manually radio-controlled and focused on live picture-taking. UAVs I have seen that might be put to use on the farm must be charged, taken to the field, flown around the field, and then the pictures (or other data) downloaded off the UAV (by bluetooth, WiFi, or transfer from some kind of flash card). This is a significant commitment of time, which limits how often you can really use the drone. A crop scout may be able to save a lot of the time he would normally spend by using a UAV to survey fields, but there’s benefit to the grower having a drone or drones that would continually survey fields.

The reason I am particularly interested in Ag Drones is because I believe they can become an important part of the day-to-day information-gathering apparatus. To be truly useful, however, I believe they must be:

  • Autonomous: flying over your fields automatically without intervention. Ideally, they would have a “home” out in the field where they would stay, and they would do their flying at specific times with no human interaction needed.
  • Smart: able to recognize problems and take appropriate action – recognize if there is something different in the fields, avoid danger, and report back
  • Connected: automatically uploading data collected and sending alerts to you as needed. For instance, a drone flying over your fields taking infrared photos might use the wireless farm network to automatically upload the pictures to a service that automatically scans them for anomalies indicating crop stress.
  • Self-maintaining: self-charging and self-monitoring, needing little maintenance and letting you know when it needs “help”

My own vision is that an Ag drone should be programmed with pre-configured flight paths and connected via WiFi with a wireless farm network for constant (or at least mostly constant) communication. It should be able to download changes to its schedule and pre-configured flight paths off the network, and It should also be able to land on a platform that will automatically charge the drone’s batteries for the next flight. Set up this way:

  • The grower, scout, or agronomist doesn’t have to go out and mess around with the drone – it can just do its thing as often as it needs to (pending charging of the batteries)
  • The data can be automatically collected on the grower’s PC or on a central server (on the farm or on the Internet) – it can even be automatically processed and problems (plant stress, aberrant weather conditions, etc.) can be automatically reported to the grower
  • The drone works for the farmer, not the other way around.

All the pieces exist today to create drones that can meet these criteria, but I’m not aware of any pre-built planes or copters that are ready-to-use. However, there are open-source software projects that have built auto-pilot systems for drones and other robots (e.g. the ArduCopter), and there is discussion of induction charging of quadcopters in the “DIY” forums. And heavier-lift copters (capable of picking up fairly heavy items and transporting them) are also in the works. Imagine being able to get out your cellphone and “tell” your copter to bring you the parts you forgot back at the workshop, then hearing it whirring its way toward you a few minutes later. And then, when it delivers them, it DOESN’T TELL YOU YOU’RE AN IDIOT for forgetting the parts. For me, that would be nearly priceless.

In short, I think there are a lot of possible benefits from using UAVs on the farm, and I’m eager to see them start to deliver those benefits. However, I think a lot of the benefits are greatly enhanced by having the UAVs connected to a wireless farm network – I believe the two technologies will work hand-in-hand, each enhancing the value of the other.