Bank security systems are now so sophisticated that it is virtually impossible to use a hankie without being in full view of a surveillance camera. Uniformed guards making their presence obvious are as much an ornament as a deterrent to crime.
“Dark fiber” is a term often heard in conversations about fiber optic communications. Perhaps this is because it has a name that sounds evil or nefarious. But dark fiber is just fiber that has been installed and is not currently in use; instead, it is reserved for spares or future use.