Rational Survivability

Here’s an interesting resurgence of a security architecture and an operational deployment model that is making a comeback:

Requiring VPN tunneled and MITM’d access to any resource, internal or external, from any source internal or external.

While mobile devices (laptops, phones and tablets) are often deployed with client or client-less VPN endpoint solutions that enable them to move outside the corporate boundary to access internal resources, there’s a marked uptake in the requirement to require that all traffic from all sources utilizing VPNs (SSL/TLS, IPsec or both) to terminate ALL sessions regardless of ownership or location of either the endpoint or the resource being accessed.

Put more simply: require VPN for (id)entity authentication, access control, and confidentiality and then MITM all the things to transparently or forcibly fork to security infrastructure.

Why?

The reasons are pretty easy to understand.  Here are just a few of them:

1. The user experience shouldn’t change regardless of the access modality or location of the endpoint consumer; the notion of who, what, where, when, how, and why matter, but the user shouldn’t have to care
2. Whether inside or outside, the notion of split tunneling on a per-service/per-application basis means that we need visibility to understand and correlate traffic patterns and usage
3. Because the majority of traffic is encrypted (usually via SSL,) security infrastructure needs the capability to inspect traffic (selectively) using a coverage model that is practical and can give a first-step view of activity
4. Information exfiltration (legitimate and otherwise) is a problem.

…so how are folks approaching this?

Easy.  They simply require that all sessions terminate on a set of  [read: clustered & scaleable] VPN gateways, selectively decrypt based on policy, forward (in serial or parallel) to any number of security apparatus, and in some/many cases, re-encrypt sessions and send them on their way.

We’ve been doing this “forever” with the “outside-in” model (remote access to internal resources,) but the notion that folks are starting to do this ubiquitously on internal networks is the nuance.  AVC (application visibility and control) is the inside-out component (usually using transparent forward proxies with trusted PAC files on endpoints) with remote access and/or reverse proxies like WAFs and/or ADCs as the outside-in use case.

These two ops models were generally viewed and managed as separate problems.  Now thanks to Cloud, Mobility, virtualization and BYOE (bring your own everything) as well as the more skilled and determined set of adversaries, we’re seeing a convergence of the two.  To make the “inside-out” and “outside-in” more interesting, what we’re really talking about here is extending the use case to include “inside-inside” if you catch my drift.

Merging the use case approach at a fundamental architecture level can be useful; this methodology works regardless of source or destination.  It does require all sorts of incidental changes to things like IdM, AAA, certificate management, etc. but it’s one way that folks are trying to centralize the distributed — if you get what I mean.

I may draw a picture to illustrate what I mean, but do let me know if either you’re doing this (many of the largest customers I know are) if it makes sense.

/Hoff

P.S. Remember back in the 80’s/90’s when 3Com bundled NIC cards with integrated IPSec VPN capability?  Yeah, that.