First installment in an occasional series.

Tucked away on the sprawling show floor at the recent RSA Conference was a newly commercialized appliance that sits inside the network and spies on attacks already in progress. Its mission isn't to stop the attacker from getting in, but instead to stealthily observe the attacker's moves while gathering intelligence and ultimately containing any damage.

Assuming the attacker is already inside, or soon will be, is a gradual but significant mindset shift under way in the security industry, which has been built on a defensive strategy of firewalls, antivirus, and other tools. There's now a growing sense of fatalism: It's no longer if or when you get hacked, but the assumption that you've already been hacked, with a focus on minimizing the damage. The new appliance demonstrated at RSA was an example of approaching security from the view of being resigned that the bad guys are getting in, even with your defenses in place, security experts say.

"The dirty little secret in our industry is that everyone has been compromised," says Darin Anderson, U.S. country manager for Norman Data Defense Systems.

Kevin Mandia, founder and CEO of Mandiant, echoed the same sentiment at the recent B-Sides Conference in San Francisco. "I believe security breaches are inevitable," he said. "We're always trying to dumb down security, but we need to scale our experts, and we need software that scales" with experts and is more than just blinking red or green lights, he says. Visibility into what's going on in your network is key, he said.

This philosophical shift toward most everyone -- not just high-profile government agencies or corporations -- accepting breaches as a fact of life is a result of the increase in successful and hard-to-kill advanced targeted attacks, most of which come from nation-state adversaries hungry for intellectual property and other competitive intelligence. These attacks, which were once the bane of mostly just the military and defense industrial base, are now spreading to all corners of the commercial world, even hitting smaller but just as lucrative targets, such as law firms.

Preventing these attacks -- which typically originate from a phishing attack on a user who falls for a lure -- is difficult. And the high-profile hacktivist-driven attacks from Anonymous demonstrated that when a determined attacker wants to get in, DDoS you, or "dox" you for hacktivist purposes, he will likely find a way to shame your organization.

These attacks, as well as increasingly sophisticated ones aimed at financial gain, have in some cases led to the perspective among many security experts, vendors, and enterprises frustrated with existing security technology and poor security practices within organizations -- think weak and reused passwords and other glaring missteps -- that there's little you can do to stop the bad guys from hacking you.

"They will get in and they are there," says Neal Creighton, chief executive officer at CounterTack, the vendor that showed off its KVM RedHat-based appliance commercially at RSA for the first time after working under the radar mostly with federal agencies facing advanced persistent threat (APT) attackers. "Everyone is getting hit. We are afraid of what we don't know."

Some 70 to 80 percent of organizations surveyed by The Ponemon Institute say they have experienced one or more data breach in the past 20 months. "That's large, but it could be that only a couple of records [were compromised in some cases]. But most [organizations] are recognizing the fact that they are not clean," says Larry Ponemon, chairman and founder of Ponemon Institute. "The key is if you prioritize your data protection activities, focus on the information that leaks can really harm you and protect that."

[Financially driven cybercriminals are also using advanced persistent threat (APT) methods for longer staying power in order to increase their spoils. See APT-Type Attack A Moving Target. ]

It's not that defensive postures are no longer relevant. It's just that defense alone is no longer the answer, experts say. Organizations need to beef up their detection and intelligence-gathering, they say.

"I've said for awhile if someone wants to infiltrate [your organization] and they have the resources and time, they will probably be successful," says Wade Baker, director of risk intelligence for Verizon. "We should be preventative. But that's temporary, and one of the reasons that's temporary is that you can't stop everything and you need to know when something occurred. Security is about prevention and detection."

It's also about looking at security differently and finding a new way to market security, according to Marc Maiffret, CTO and co-founder of eEye Digital Security.

"The current message of 'assume compromise' is both a different way of looking at security and a different way of marketing security," Maiffret says. "You can still stop the vast majority of attacks today through proper network architecture, system configuration, and timely patch remediation. That has not changed, but that is not a sexy thing to market," either, he explains.

"[But] one thing I have said for a long time is that anyone in security telling you their product or service will make you 100 percent secure is lying or ignorant," he adds.

The aim now is to try to detect an attack as early in its life cycle as possible in order to lessen the impact of an attack.

It's akin to traditional military strategy, says Dmitri Alperovitch, a member of the board of directors at CounterTack and a co-founder of CrowdStrike. "Assume they have gotten through your defenses," he says.

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