Burning beacons on hill-tops have long been used to warn of advancing Armadas and their like. However, the author believes that beacons may have wider applications than just these. They keep you warm. A secondary use for the disposal of those nasty ISO people. Not cluttered with unnecessary functionality.
Error rates can be high.
Semaphore has been in use for many years. This is difficult to determine, but is probably due to political motivations rather than any deficiencies in the protocols. Naturally there are a few rough edges to be addressed. Advantages over OSI a. Broadcasts are easily accommodated.