The diagram at left depicts this situation, so let's examine each item in turn.
Availability is probably the defining aspect of IT. If the resource isn't available, no one cares about much else. Availability problems are almost exclusively the responsibility of IT, with "uptime" being their primary metric.
One would expect confidentiality to be fairly central to any "security" team's role. Exfiltration of data is partly a confidentiality problem. However, the biggest headache in the confidentiality world has been disclosure of customer personally identifiable information (PII) via loss or theft of physical assets (laptops, backup tapes) or electronic exposure. Companies now employ dedicated Privacy teams, usually staffed predominantly by lawyers, to specifically address the handling of customer PII. One might have thought the "Security" team should have had responsibility for this subject. Instead, a legal problem ("Do we have to disclose the breach to customers and/or the public?") is being addressed by lawyers.
Integrity is the last of the three, and originally I thought it would be the core "security" task for the "Security" team. Then I remembered Sarbanes-Oxley and Section 404. I wondered if the Audit Staff's requirement to assess the "integrity" of records meant they had a more institutionalized role in this area than the "Security" team.
So what does this mean for "Security" teams? Looking at the problem in one way, you might think there is no need for a Security team. CIA is covered by three groups, so Security is redundant. This is a mistake for the following reasons.
- The IT staff is not equipped to resist attacks, especially advanced ones. IT usually does a good job keeping resources functioning when equipment failure, provisioning woes, or misconfiguration causes downtime. IT is usually ill-equipped to stop intelligent adversaries who are three steps ahead of overworking administrators.
- If an IT staff can't handle attackers, there's no way lawyers can. Lawyers tasked with security responsibilities usually outsource everything to high-priced consultants. Legal teams have the budgets for this, but it's not a sustainable situation. Privacy teams focus on salvaging the company brand and market value after a breach; they are not positioned to resist or detect incidents.
- Auditors look for problems and effect change, but they do not implement change. They look for weaknesses in processes and configurations, not intruders who have exploited those vulnerabilities.
I believe this state of affairs leaves the Security team as the one group that has the proper mindset, subject matter expertise, and ability to implement defensive operations to preserve CIA. This mission is not one the Security team accomplishes by itself, if that ever were possible. Rather, Security will (if not already) need to pair itself with IT, Audit, and Privacy in order to be effective. One could say the same for and Compliance groups, Governance officers, and/or Physical Security teams, although I'm less worried about those ties right now.
It should be clear at this point that it doesn't make sense for the Security team to work for IT, given the role it must play. A Security team working for IT is likely to be stuck supporting the Availability aspect of "security" at the expense of the other CIA elements. Furthermore, it could be difficult for Security to build the necessary bonds with Audit and Privacy if those groups see the Security team as "just part of IT," or "technologists."
In this light, it makes sense for Security (CISO) to be next to IT (CTO) in the corporate hierarchy, both working for the CIO. Ultimately the CIO is responsible for the company's information, so I don't see a way for [information] Security to be beyond the CIO's reach.
How does this review compare to your own experience?