Asynchronous communication for effective grid down strategies
Asynchronous communication lets you send and receive messages in short bursts without both having to be on the air at the same time
I’ve been following podcasts by Julian OH8STN on YouTube, and one of the overarching themes in communications prepping is the importance of the asynchronous strategies for disaster preparedness communications. He puts particular focus on communication “with your people” who can be, for example, your family, friends or community.
According to Julian, synchronous voice communication may not always be effective in times of emergency. The biggest reason is that you might not always be standing by at your radio station waiting for messages.
In contrast, asynchronous communication lets you send and receive messages in short bursts without both having to be on the air at the same time. This has opsec advantages as well, because you can minimize transmissions and don’t have to be at the same place at the same time all the time.
This means you can leave a message for later retrieval, and vice versa.
Julian discusses the benefits of NVIS or near-vertical skywave propagation, wherein HF signals are bounced off of the ionosphere for messaging without grid or infrastructure.
Locally, I advocate the use of the different packet-based systems for communicating among radio amateurs. There is a growing community of packet radio users, which come in different platforms and applications.
- There is Winlink, which can be used to send emails and files over-the-air. Given the slow nature of local VHF packet, however, this is best done for text emails and small documents.
- There is also APRS, whcih lets users share positions and short text messages. This can be done through either radios that have APRS capabilities built-in, or by interfacing radios with a computer (e.g. raspberry pi) or smartphone.
For one, I manage the APRSPH net, which is a daily rolling net that enables people to share short messages and also read messages stored on the local server.
These messages can be processed and retrieved in a fully-RF only envoronment, which means there is no internet needed. It can even be used as a means to share incident reports for parsing and processing by incident command.
This expands on the functionality of APRS, which itself has messaging but no asynchronous store-and-forward capability.
I am learning a lot of these myself, but I would be happy to share what I know. I am also aware that some have focus or expertise on other off-grid data communications techniques, such as mesh networking. I would be happy to learn more about these, too.
#amateurradio #communications #communicationsresiliency #griddown
