Maybe messages should include a coarse timestamp to prevent replay of old messages by some adversary.<p>Someone could resend a month old "yes" with your valid signature to a question someone asks now.<p>Also it might be beneficial to include sequence numbers or message IDs and for example echo the last 4 ids in following messages so recipients can detect holes. - The chat could insert some placeholder to notify recipients of missing previous messages.
Does this do any sort of FEC? One of the things that makes stuff like this tricky(and APRS in general) is that one flipped bit throws off the whole decode.<p>From what I've seen out there would be a 40% improvement[1] in just base APRS if there was some form of basic FEC built into the protocol. Sadly most of "state of the art" is stuck back in the 80s.<p>[1] <a href="http://eludium.stensat.org/mcguire/projects/FX-25/FX-25_performance.htm" rel="nofollow">http://eludium.stensat.org/mcguire/projects/FX-25/FX-25_perf...</a>
<i>An AX.25 packet radio chat protocol with support for digital signatures and binary compression. Like IRC over radio waves</i><p>I just wanted to say thank you for such a concise, <i>clear</i> summary. So many projects get posted with cryptic descriptions full of insider terms.
Cool project! I have always been interested in the amateur radio scene.<p>So encrypting amateur radio comms is illegal in the US? Is there a particular reason for this?
> With amateur packet radio anyone can pretend to be anyone else. With Chattervox, you can be sure you're chatting with the person you intend to.<p>This is a great idea, for both the community and as a hobby project. Has there been any other attempts at similar protocols for amateur radio?
This is pretty neat, and its nice that I already have all the pre-reqs :-). Although I'm wondering if I have to use the analog cable for the radio as I've got the USB one, that will be a bit of investigation.