This column is about computer-based espionage and how we can defend our organizations against it. But I'd like to start with a mood piece of sorts.

There has been too much noise about information warfare lately. Distributed denial of service and defacement attacks like what happened in Estonia and Georgia come to mind.

The following two stories give a better understanding of what it is really about, without resorting to more scary stories about what China is or isn't doing. We'll also touch on other interesting cases such as the Israeli Trojan horse case, when we talk about defensive measures against computer-based espionage and targeted attacks.

The first is a report (without much detail or proof) on North Korea being involved in operations against South Korea using Trojan horses for espionage. The second is a lesson from history called the Farewell Dossier - a collection of intelligence documents KGB defector Colonel Vladimir Vetrov (code-named Farewell) handed over to NATO during the Cold War.

This information led to a mass expulsion of Soviet technology spies. The CIA also mounted a counter-intelligence operation that transferred modified hardware and software designs over to the Soviets, resulting in the spectacular trans-Siberian incident of 1982, in which a huge explosion ripped apart a trans-Siberian pipeline. The resulting explosion was so big, it was supposedly confused for a nuclear explosion by American decision makers until the CIA said, "Oh, that's one of our operations."

It wasn't a bomb that destroyed the natural gas pipeline and sent shock waves through the economy of what was then the Soviet Union. Instead, it was a software virus created by the CIA, according to a book by Thomas Reed, a former US Air Force secretary and National Security Council member.

What does this mean? While destructive attacks are certainly of significance and important to defend against as they impact us directly, regardless of who the attacked party is or where in the world they are (DDoS attacks harm the Internet and its users), smarter, quieter attacks are all around us. How do we defend against them?

I expect most information warfare acts to be targeted, quiet, and covert. Espionage, or spying if you like, is not relevant to us unless we are the target. The diplomats and the intelligence communities of different countries can figure it out for us. It is an old occupation, and well covered by international law. Computers are simply another tool, or capability, to be used by these same people. There is nothing new here as far as how the game is played.

And yet, what if you are a target?