Hello fellow radio/network geeks!
While trying as much as I can to not come off as condescending, I would like to try and provide a little perspective so that we can hopefully clear up some confusion and speak in mutually agreeable terms.
There seems to be many misconceptions by several people on this list who may be seeing 44net as a single service or network where everyone needs to be able to speak to each other and where all traffic sourced from it can be trusted. Oh, and RADIO :)
The global internet isn't even one large network in that sense. It's actually just a concept that allows many different individual autonomous networks to coordinate and cooperate with each other while allowing them to share traffic among their users. Those in control of things like allocating IP space and DNS are only in that position because the majority of networks recognize their authority.
Just like similar authorities on the internet, ARDC is just a registry that provides chunks of the globally unique IP space to individual networks which allows them to interoperate with each other or any other global network without conflict (but does not mean that they *must* work with other networks). In this case, they only agree to provide these services to networks that support amateur radio in one form or another. It just so happens that they also provide a service that coordinates IPIP tunnels so these networks can send encapsulated traffic to each other without needing to make their own peering arrangements with other networks on the internet at large. Since most people are only used to the idea of the internet being a "service" provided to them, it's easy to see why this can be confused.
Those familiar with the HSMM projects may have noticed that they chose to operate in the non-unique 10/8 space in order to support autoconfiguration. However, once their project grew beyond those specific linksys models, they started having conflicts. Even now, those HSMM networks that are up and running can't communicate with users on other networks without complicated NAT tables. It would be much better to take advantage of our 44/8 resources for those projects by assigning blocks to each mesh island. That way they can start peering with other networks or other mesh islands directly. When asked why having 44/8 is important, this is a perfect example and there are many others.
When talking about technical solutions to problems we come across, it's also important to consider that as hams, it's likely that our networks are experimental and will therefore have a wide range of configurations that could prohibit their ability to share traffic with some others. This should absolutely be encouraged as long as what they do does not impact any other network's ability to operate normally. Therefore, there is no "right" or "wrong" way to configure your network as long as you get your expected result. Just keep in mind that following best-practices is the best way to ensure compatibility. Ideally, those who operate the registry will shift closer to this way of thinking and start supporting more advanced users to do non-standard things (such as DNS or PTR delegation, for example).
We also need to be careful about the terminology we use when referring to security, in order to avoid mistaken assumptions. Source addresses can be used in our case to provide a convenient filter against the majority of incoming junk internet traffic. However, this must not be confused for "authentication" or knowing *who* is sending you the packets. Make sure you understand the risks when opening up a service on your network. If you're trying to filter out most undesirables, source filtering can be okay. However, if you need to know who you are talking to, you must use another method. Also, myself and several others on this list may be in a good position to help if you need assistance in this area.
Best regards,
-Cory NQ1E Your friendly neighborhood radio hacker