What's good for the Internet is good for spies.

These days, keeping a secret is almost impossible; almost being the key word here. And some people are willing to spend good money on playing the spy game on the Internet.

Dec. 22 (Bloomberg) -- Business is booming, with annual revenue of $3 billion to $5 billion growing as much as 20 percent a year, ISS organizer Jerry Lucas estimates. 

Back at the hotel, the night is young and the paranoia is deep.

Unlike typical trade shows, this one has no social events. No corporate-sponsored cocktail parties. No hospitality suites. Clients and suppliers don’t want to be seen with each other in public, and some countries bar their agents from mingling at the event because it’s a recruiting ground for spies seeking sources, organizer Lucas says.

Quantum computing, if it ever comes to a reasonable implementation, is going to be a game changer in this market. Maybe it already is.