Self Healing Intrusion Tolerance…
Tim Greene from Computerworld wrote a story last week titled "Security software makes virtual servers a moving target."
This story draws attention to a story on the same topic that popped up a while ago (see Dark Reading) about some research led by George Mason University professor Arun Sood that is being productized and marketed as "Self Cleansing Intrusion Tolerance (SCIT)"
SCIT is based upon the premise that taking machines (within a virtualized environment) in and out of service rapidly and additionally substituting the underlying operating systems/application combinations reduces the exposure of attack and hastens the remediation/mitigation process by introducing the notion of what Sood calls "security by diversity."
Examples are given in the article suggesting the applicability of application types for SCIT:
SCIT is best suited to servers with short transaction times and has been tested with DNS, Web and single-sign-on servers, he says, which can perform effectively even if each virtual server is in use for just seconds.
In today’s multi-tier, SOA, web2.0, cloud-compute, mashup world, with or without the issue of preservation of state across even short-transactional applications, I’m not sure I see the practical utility in this approach. The high-level concept, yes, the underlying operational reality…not so much.
Some of you might notice the, um, slightly different comparative version of Sood’s acronym reflecting my opinion of this approach in this blog entry’s title… 😉
I think that SCIT’s underlying principles lend themselves well to the notions I champion of resilient and survivable systems, but I think that the mechanical practicality of the proposed solutions — even within the highly dynamic and agile framework of virtualization — simply aren’t realistic today.
Real-time infrastructure with it’s dynamic orchestration, provisioning, governance, and security is certainly evolving and we might get to the point where heterogeneous systems are autonomously secured based upon global policy definitions up and down the stack, but we are quite some time away from being able to realize this vision.
You will no doubt notice that the focal element of SCIT is the concept of a security-centric perspective on lifecycle management of VM’s. It’s quite obvious that VM lifecycle management is a hotly-contested topic for which many of the large infrastructure players are battling.
Security will simply be a piece of this puzzle, not the focus of it.
This is not to say that this solution is not worthy of consideration as we look out across the horizon, and from a timing perspective it will likely surface again given it’s "ahead of it’s deployable time" status but I’m forced to consider what box I’d check in describing SCIT today:
Neat stuff, but if you’re going to take investment and productize something, it’s got to be realistically deployable. I’d suggest that baking this sort of functionality into the virtualization platforms themselves and allowing for universal telemetry (sort of like this) to allow for either "self cleansing intrusion tolerance" or even "self healing intrusion tolerance" is probably a more reasonable concept.