It wasn't quite like that (at least in the usual cases). You had to do something that would get the other end to send it back out again, such as putting it in a

It wasn't quite like that (at least in the usual cases). You had to do something that would get the other end to send it back out again, such as putting it in a ping payload. The reason for the "bug", if I'm remembering correctly, is that Hayes or US Robotics or some company like that had a patent on the guard times that were supposed to surround the +++.