First this is stuff that should be arranged ahead of time. While it is possible to do this after the fact it is much harder. This is also a subject I have spent the last couple years looking into. I was taking an approach of anonymous as well as robust in terms of fault tolerance (nodes vanishing forever). That adds a bit of complexity.
As for fiber if its dark you need more powerful gear to get passed the losses that are inherent. "Dark fiber" is when the telephone company does not provide any signaling, repeaters or anything else on the fiber. If it is not dark fiber then you will not have a direct connect from A->B and it wont matter. This can complicate talking to the person you want to talk to. Fiber is non-conductive so it does not get the noise that copper can, but a gamma burst will disrupt it (although it will come back when the burst is over, for a nuke detonation that does not melt the fiber that is usually in less than 10 minutes). There is dark fiber gear that can do 8000km (US to Japan), generally the longer the distance the more expensive and/or slower it will be.
The wifi solution (which I have equipment to do that, in fact I have 250 watts ERP
) is a local solution. I had thought that it would be nice to have a forum, email system, and a few other things for local networking. Someone has something for sale, someone needs something, real news so that people do not rely on fear and their imagination for what is going on, etc. Even VoIP (I have over 90 telephone adapters because I worked in that business) so I could get telephones working via this.
A large scale mesh network will fail. There are a variety of reasons for this, while they work for cities they will not work for very large areas. The Daihinia solution they mention has some overhead issues as well that make it ok for local small area stuff but not an entire state even. I would be surprised if it worked well for a county.
FidoNet requires routing to be pre-arranged. Adding and removing nodes, a highly dynamic on the move constantly reconfiguring network will not play well with FidoNet. Usenet would be a better option as it not only allows for attachments (basically anything you can do in email you can do in usenet) but it supports more network reconfigs without routing from a->b to be fixed. It still makes it harder to send the message where it needs to go but if you created a group hierarchy that could be arranged. For example FreeNet.US.WY.Casper.Alice to address it to Alice. By always using the official 2 letter country codes and whatever is the official short code for a regional division in the area you are in you can segment the messages. Then you just have to sync when you go "online" and the messages flow and can be distributed by both sides over something like wifi or a more public terminal.
I also have ham radio equipment and you can do internet (or at least IP based networks) via ham radio. The least you need is a transceiver and a laptop with a sound card, the sound card may be optionally replaced with dedicated hardware to act as a modem. I have software that works very well with my sound card. I have even used APRS for text messaging on one of my handhelds that has APRS and a TNC built in. My bigger ham radio is also battery enabled, with the tuner I have I could go out into a field and use a barbed wire fence as an antenna if I have to. Transmit, move, transmit, move. Making it hard for them to isolate me if it comes to that.
I am also thinking it may not just be the gov that is trying to figure out where I am transmitting from. My scenarios go from a localized disaster like Japan or Katrina all the way to Mad Max. To that end I have actively sought options.
