Back when the spam was spiraling out of control, I configured my blog to close comments after 90 days. I’ve removed the limitation now, for two reasons: the spam is under control, and I wanted to reply to a comment made to my post on IPsec/IPv6 direct connect.
On 13 August, jcorey asked about how to deal with those who firmly believe that the only answer to any security problem is to inspect everything at the edge. This is an important question, and I wanted to give Joe an answer. (You might have to scroll down when you click the previous link, it seems that linking to individual comments is broken.)
Today, 15 October, I wrote a little thesis as an answer to his question. I’m calling it out in a separate post because I want to make sure those of you with aggregators that don’t update when posts receive new comments still have a chance to reply with your thoughts. I’ll also repost it here:
jcorey-- You've nailed the biggest obstacle to deploying something like direct connect. Many security professionals have been taught that there simply is, and never will be, a process or technology that allows you to trust anything that originates from outside your corpnet. These professionals cling to this belief, and have been the cause that allowed the whole “detection” market to bloom.
Let me be clear: this total lack of trustworthiness is no longer absolutely true. Of course there will be times when unknown machines will be used by known and unknown people to access your information. But what about one particular subset -- known humans, with known portable computers -- can't we do something better than treat them as toxic invaders?
Indeed we can. And that's what I'm proposing with direct connect. The technology -- managed, of course, with the right processes -- exists so that you can extend the trust to known computers even though you don't trust the network they're connected to. This is because you have mechanisms that:
1. Allow you to configure the machine according to your requirements (domain join, group policy)
2. Dictate computer and user authentication requirements (IPsec policies, smart cards)
3. Limit what the users of these machines can do (UAC, non-admin, Forefront Client Security, Windows Firewall, even software restriction policies)
4. Validate the health of machines initiating incoming connections and remediate if necessary (NAP, System Center Configuration Manager)
5. Limit the threat of attacks against stolen computers (domain logon, smart cards, BitLocker with TPM)
With the robust authentication, validation, configuration, and control mechanisms available to you, I simply don't see that there's any need to fall back to “detection” now. Detection technologies were -- and remain -- necessary for the times when we have no clue about the health of client computers and when we had no way to gauge the intent of the users. But it is truly reflective of a head-in-the-sand mentality to assume that this is a complete description of what's capable today.
You know, someone once asked me what it takes to be a security professional. I answered that there are two primary elements: become a networking/packet wonk, and be willing to change your opinions when the right evidence comes along. Indeed, I suspect that many security folk have forgotten the need to keep their wonikness updated, which in turn makes them resist new ideas regardless of the strength of the evidence. I'm not very proud of what I just wrote, because I loathe generalities, but I'm not sure what else to think here. Sigh.
Joe’s question is important and strikes at the foundation of what it means to be a security professional today. I’m eager to continue this conversation, because it’s reflective of what I sense to be a radical shift in our jobs—we are, or should be, no longer the wolf-crying propeller-head who sits in the basement and twiddles with the firewall. Instead, our job should be defined as one who’s charged with protecting the organization’s information from attack, while maximizing its utility to authorized users, according to the principles of least privilege. Your thoughts?