Counterpoint: Availability Is Job #1

By Mike Rothman | November 22, 2010

Rich makes the case that A Is Not for Availability in this week’s FireStarter. Basically his thinking is that the A in the CIA triad needs to be attribution , rather than availability. At least when thinking about security information (as opposed to infrastructure). Turns out that was a rather controversial position within the Securosis band.

Yes, that’s right, we don’t always agree with each other. Some research firms gloss over these disagreements, forcing a measure of consensus, and then force every analyst to toe the line. Lord knows, you can never disagree in front of a client. Never. Well, Securosis is not your grandpappy’s research firm. Not only do we disagree with each other, but we call each other out, usually in a fairly public manner.

Rich is not wrong that attribution is important – whether discussing information or infrastructure security. Knowing who is doing what is critical. We’ve done a ton of research about the importance of integrating identity information into your security program, and will continue. Especially now that Gunnar is around to teach us what we don’t know. But some of us are not ready to give up the ghost on availability. Not just yet, anyway.

One of the core tenets of the Pragmatic CSO philosophy is a concept I called the Reasons to Secure. There are five, and #1 is Maintain Business System Availability. You see, if key business systems go down, you are out of business. Period. If it’s a security breach that took the systems down, you might as well dust off your resume – you’ll need it sooner rather than later. Again, I’m not going to dispute the importance of attribution, especially as data continues to spread to the four corners of the world and we continue to lose control of it. But not to the exclusion of availability as a core consideration for every decision we make.

And I’m not alone in challenging this contention. James Arlen, one of our Canadian Wonder Twins, sent this succinct response to our internal mailing list this AM:

As someone who is often found ranting that availability has to be the first member of the CIA triad instead of the last, I’m not sure that I can just walk away from it. I’m going to have to have some kind of support, perhaps a process to get from hugging availability to thinking about the problem more holistically. Is this ultimately about the maturation of the average CIO from superannuated VP of IT to a real information manager who is capable of paying attention to all the elements of attribution (as you so eloquently describe) and beginning the process of folding in the kind of information risk management that the CISOs have been carrying while the CIO plays with blinky lights?

James makes an interesting point here, and it’s clearly something that is echoed in the P-CSO: the importance of thinking in business terms, which means it’s about ensuring everything is brought back to business impact. The concept of information risk management is still pretty nebulous, but ultimately any decision we make to restrict access or bolster defenses needs to be based on the economic impact on the business.

So maybe the CIA acronym becomes CIA^2, so now you have availability and attribution as key aspects of security. But at least some of us believe you neglect availability at your peril. I’m pretty sure the CEO is a lot more interested in whether the systems that drive the business are running than who is doing what. At least at the highest level.

17 Comments

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mokum von Amsterdam 2010-11-23
It all depends, does it not? Banks love their availability and are willing to take quiet some losses in return. Governmental agencies love their exclusivity and accept quiet some availability challenges.
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TL 2010-11-23
In France most security practitioners always refer to four dimensions : Disponibility, Integrity, Confidentiality and Proof (or Tracability). What about considering a fourth dimension of its own rather than mapping the proof requirements on the CIA ones ? Where do you cover the proof/tracibility requirements in the US ? Is the choice consistent among the security community ?
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David Mortman 2010-11-23
<i>If availability is job 1, why do we ever use fail-closed security controls?</i> Or default deny? ;-)
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sark 2010-11-23
Attribution is a nice to have (bordering on need to have depending on function)while availability is a must have. I can go without knowing who did what, (I don't like it and I don't want to for very long) but I can't go without my servers, SAN's, firewalls, etc being accessible or functioning. Let's put it this way, you can go a lot longer as a company without attribution than you can without availability.
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Andrew Yeomans 2010-11-23
What do you make of Don Parker's extension to CIA? It's defined on http://en.wikipedia.org/wiki/Parkerian_Hexad The Parkerian Hexad attributes are the following: * Confidentiality * Possession or Control * Integrity * Authenticity * Availability * Utility (Note an ISC blog entry claims that some wikipedia definitions are flawed).
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Adrian Lane 2010-11-22
Ugh. Was hoping to side-step this comment, but your counter-point forces my hand: attribution is just a tool. Availability is a goal. Attribution is a critical tool for data security implementations, but I just don't see why we need to mix it into the C-I-A model. -Adrian
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Mike Rothman 2010-11-22
Expand on this Adrian. Or do your own counter-point post. If C, I, and A are *goals*, and attribution is a tool, what other *tools* do we need to worry about? I kind of like the distinction between a tool and a goal, but I think it needs to be fleshed out a bit better. And yes, folks this is how the sausage is made.
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Rich 2010-11-22
To defend myself a bit before I jump into an all day meeting... If availability is job 1, why do we ever use fail-closed security controls?
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ds 2010-11-22
If attribution is a tool, what goal is it supporting?
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Mike Rothman 2010-11-22
@rich, availability is a business decision. Business folks may decide the risk of fail open is not acceptable. *That is their choice.* Ultimately it's about giving business managers the information they need to make decisions, understanding the risk of said decisions. If they decide Fail Closed is the right business decision, then we do that at the cost of potential availability. My point is that arbitrarily making that choice without input from the business is a bad idea.
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Dean 2010-11-22
If Availability is not a major security concern, please explain to me what to say to the CIO when he receives a message from a cyber-extortionist threatening a DDoS from a botnet that he controls unless the company forks over a lot of cash, and I tell him that my high-priced consultants recommended that I omit availability from my security strategy.
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Rich 2010-11-22
Dean, Take a look at my comments in the other post. C I and A are always in conflict- keep it safe? Or keep it running? As Mike said those are business decisions we inform and implement. But if my focus is on "protecting the data", then availability is what I will most likely drop. If the goal is to keep the site up? Which might be more or less important? Then C and I drop. I fully agree that the primary goal of infrastructure-centric security is availability. But for information-centric/data security? Then it falls more into usability. (and give me a little credit- I'd never make such a stupid statement to a CISO within that context. I'd have been out of business a long time ago if I acted like that).
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Adrian Lane 2010-11-22
@Mike - attribution is a prerequisite for information centric security. You need attribution of some type to prescribe of suitable controls to the data. And remember, Rich's post is based upon Quantum Dataum, a finite unit of data. The entire thread must is made from that perspective. I just want to keep what we want to do (C-I-A) from how we want to do it. -- @Rich - I'd like to see more 'fail-closed' models. -- @Dean - DDoS is _so_ 2002. Seriously though, can you imagine the complains from users if they could not buy a Thigh Master over an unsecured connection while at Starbucks with their Windows98 laptop and IE6 browser? Heck, they'll just drive to Walmart to avoid the hassle. That said, whenever my credit card has been rejected for on line purchases the error does not tell me anything, the online merchant is not permitted to tell me anything, and the credit card company won't tell me why that particular transaction send their fraud detection system into overdrive. Useful information and responses would help the merchants in this regard ... but I digress. -Adrian
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Matt Franz 2010-11-22
I always thought it was CIA^2N where the additional A is for "authenticity" (which is pretty damn close to attribution, whether your are talking about DATA or Network Communications) and the N is for Non-Repudiation, but then of course come folks argue that Integrity = Authenticity. But this could easily degrade into an academic argument, if it hasn't already ;)
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Gunnar 2010-11-22
I agree that availability is job 1, its just not security's job. We have built approx zero systems that have traditional cia, time to move on.
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Lubinski 2010-11-22
"everything is brought back to business impact" Does this statement not require A to equal availability? The distinction between infrastructure and information is required at this point. I can imagine information security as being layered on top of infrastructure security with its own defined set of goals and tools which in turn equals a different set of definitions for the C-I-A model. Do we have information security without the infrastructure? Assets->Risks & Threats->Vulnerabilities->Risk Mitigation->Business Impact Analysis->Business Continuity A = availability.
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LonerVamp 2010-11-22
I'm simply game to hear more about the data-centric side, so that regard, nice preluding post from Rich! :) Availability is nearly as much security's job as general IT's job, if you ask me. More for general IT, but security has to certainly be aware of it both in what they implement and in what they monitor. The business, however, has a huge interest in it, and that can (and does) eclipse anything else. It would take a fairly narrow focus/job to be able to walk away from Availability. (Does data-centric narrow it enough? I don't know.) Without Availability, the old example of an unplugged server locked in a room with a laser pointed at the data on the disc ready to zap it should it be moved an inch in either direction, actually becomes the security answer? Nonetheless, I'm still game to hear more about data-centric security (Quantum Datum?), and see where it is more compatible with Attribution. That probably means re-stating definitions for C and I as well, when working into the new A.