MikroTik LHG

I’ve been curious ever since June to learn more about RMHam’s microwave data network that they deployed up at the Dirty 30, so I started doing some research and asking questions.

My research brought me back to AREDN; I’d seen references to it in the past but this time I dug in a bit further. In concept, it’s an ad-hoc mesh IP network operating on microwave ham bands. The frequencies are close enough to Wi-Fi that even some consumer Wi-Fi access points like the Linksys WRT54G will work, although commercial equipment like Ubiquiti is recommended. Hams can opt to put up a node on their shacks, become part of the mesh, and use any services available elsewhere in the mesh. Services include things like chat, file sharing, VoIP audio/video conferencing and IP webcams. Internet access can also be piped in, although due to the prohibition on encryption on ham bands, it can’t be raw internet access. AREDN sounds like it’s closely related to BBHN.

This sounded useful and somewhat similar to RMHam’s system, so I asked a couple of folks about it. Apparently they haven’t adopted AREDN because they’ve had some negative experiences with it. Pueblo County ARES attempted to deploy a large AREDN system, but found that it didn’t integrate well with non-AREDN systems, particularly RMHam’s existing microwave IP network. It turns out some of the autoconfiguration magic of AREDN that allows any ham to get a node up and running quickly also interferes with being able to interoperate with other systems. Specifically, all AREDN nodes use private network addresses, which means anyone outside of AREDN can’t connect to services inside without having some sort of network address translation (NAT) in place. That could probably be overcome with something similar to UPnP, but Pueblo ARES also apparently found that the network was not reliable; I didn’t ask further on that point.

Instead of using AREDN’s autoconfiguration, RMHam prefers to manually manage most of the details. They prefer MikroTik hardware, use a lot of static IPs and select their own routing protocols; this lets them interop with commercial ISPs and access the entire network directly. I hope to learn more about how RMHam conducts business. I’m not savvy enough at networking to say whether all of this is necessary. I like the idea of network autoconfiguration, but I’m enough of a computer power user to know that choosing “auto” isn’t always the best option.