There are many modes and methods available for emergency communications. One-way forms, such as radios and scanners, are useful for obtaining facts and directions needed in an emergency. Two-way modes, such as walkie-talkies and phone calls, are vital for exchanging such information with whom you need to contact. Both one-way and two-way forms are necessary for increasing your chances of survival in any given emergency, whether large or small.
Amateur radio is a very effective form of two-way communications, and it is one that has one of the greatest number of methods of which to use. One of these methods is known as a mesh net. A mesh net, defined, is a network of individual radio nodes (usually wireless) which can flood the entire network with certain information, or it can route given data from node to node until it reaches its intended destination. One of the benefits of mesh nets is that they are “self-healing.” That is, if one node breaks down or goes offline, the information will continue to reroute itself through the network. Another more important benefit to mesh nets is that they are not dependent upon the internet. In fact, if the internet went down in the event of an emergency, mesh nets could be used to pass along much of the same information. In addition, mesh nets can use alternate power sources, so they are not necessarily rendered inoperable if the grid was ever interrupted. This aspect of being able to deploy a mesh net in a grid-down event to exchange information makes it a very valuable method of emergency two-way communications.
Although one does not need an amateur radio license to operate a mesh net, (since they can be set up using a variety of technologies and protocols,) ham radio mesh nets are very accessible as long as one has an amateur radio license. These ham mesh nets, also known by the names of HSMM-MESH or Broadband-Hamnet, are collaborations of amateur radio operators who independently set up and operate individual nodes. Each node becomes part of a bigger network as other nodes are able to receive its given signal. Through the network, hams are able to exchange data using a variety of methods. Here is a sample of what one can do across a ham mesh net:
- send FTP files
- send/view webcam images
- use VoIP phones
- utilize instant messaging
- access the internet
- share a network drive
- video chat
- send/receive email (via Winlink)
Those are just some of the possibilities of what one can do. However, one should keep in mind that since it is ham radio, ham mesh nets cannot be used for those purposes restricted from amateur radio (i.e. music, business interests, etc.) Regardless, it should still be clear that mesh nets would prove very useful for sending and receiving information in the event of an emergency. In fact, that was the very purpose for which they were originally intended. Thankfully, it doesn’t take much to get involved and set up your own node. All you would need besides an amateur radio license you may already have on hand.
What would you need?
At the very least, one needs a router that is capable of being flashed with new firmware. Many of these can be picked up cheap. (I picked up mine at a thrift store for $5.) The particular firmware I utilize is free, and it is found on http://www.broadband-hamnet.org/. A list of compatible hardware is found there as well. In essence, what happens is that once the router is rebooted with the new firmware, it becomes (in a sense) a ham radio which sends out your call sign by beacon. Ham operators can do this since our licenses allow us to receive, experiment with, and transmit radio signals within the frequency bands that these commercially-made routers use. Besides the router, all one then needs is some kind of interface (like a PC,) and an Ethernet cable with which to connect them. That’s it. As I said, it is quite possible you may have all you need lying around. Of course, you may desire to add other equipment as you wish, such as better external antennas, VoIP phones, or an IP webcam, but that would be all up to you and how you wish to interact with others through the mesh net.
Interested to find out more? Then go to http://www.broadband-hamnet.org/ to learn from those who actually wrote the firmware and began it all. There is information on how to get started, pdf guides to download, and a PowerPoint to aid you through the process of setting up your node. There are also forums which you can access to learn about what you can do once you are on the air.
Oh…one more thing. This may not be for everyone. Even though much of the work has already been done, there is a learning curve. If you have no interest in putting in some mental effort into learning something new, then this may not be for you. Even with everything available, you may still need to do some research, and you may need to experience some trial and error before you get up and running. (That was the case for me.) If you are experienced with networking and computers, then it will probably be a breeze. But if not, it is still quite possible to do this if you are willing to learn a bit. In reality, it is not that difficult, so don’t be discouraged. It is all just part of the process of learning a new skill, just as it is with learning anything else. If you are willing to make the effort, you can do it. If you feel like this could add to your emergency communication preps, then it may be worth a try.