Radio Shortest Path First
RSPF is a specialised routing protocol that is used by amateur radio operators to work out how to shuffle packets around our complicated networks. There are many reasons why our networks are complicated, but one significant thing is that you can no longer assume that just because you hear one station, then they can hear you. This means you can have a lot of unidirectional routes. This is why standard protocols don't work very well over amateur packet radio.