As I continue to think about the opportunities that Software Defined Networking (SDN) and Network Function Virtualization (NFV) bring into focus, the capability to deliver security as a service layer is indeed exciting.
I wrote about how SDN and OpenFlow (as a functional example) and the security use cases provided by each will be a differentiating capability back in 2011: The Killer App For OpenFlow and SDN? Security, OpenFlow & SDN – Looking forward to SDNS: Software Defined Network Security, and Back To The Future: Network Segmentation & More Moaning About Zoning.
Recent activity in the space has done nothing but reinforce this opinion. My day job isn’t exactly lacking in excitement, either 🙂
As many networking vendors begin to bring their SDN solutions to market — whether in the form of networking equipment or controllers designed to interact with them — one of the missing strategic components is security. This isn’t a new phenomenon, unfortunately, and as such, predictably there are also now startups entering this space and/or retooling from the virtualization space and stealthily advertising themselves as “SDN Security” companies 🙂
Like we’ve seen many times before, security is often described (confused?) as a “simple” or “atomic” service and so SDN networking solutions are designed with the thought that security will simply be “bolted on” after the fact and deployed not unlike a network service such as “load balancing.” The old “we’ll just fire up some VMs and TAMO (Then a Miracle Occurs) we’ve got security!” scenario. Or worse yet, we’ll develop some proprietary protocol or insertion architecture that will magically get traffic to and from physical security controls (witness the “U-TURN” or “horseshoe” L2/L3 solutions of yesteryear.)
The challenge is that much of Security today is still very topologically sensitive and depends upon classical networking constructs to be either physically or logically plumbed between the “outside” and the asset under protection, or it’s very platform dependent and lacks the ability to truly define a policy that travels with the workload regardless of the virtualization, underlay OR overlay solutions.
Depending upon the type of control, security is often operationalized across multiple layers using wildly different constructs, APIs and context in terms of policy and disposition depending upon it’s desired effect.
Virtualization has certainly evolved our thinking about how we should think differently about security mostly due to the dynamism and mobility that virtualization has introduced, but it’s still incredibly nascent in terms of exposed security capabilities in the platforms themselves. It’s been almost 5 years since I started raging about how we need(ed) platform providers to give us capabilities that function across stacks so we’d have a fighting chance. To date, not only do we have perhaps ONE vendor doing some of this, but we’ve seen the emergence of others who are maniacally focused on providing as little of it as possible.
If you think about what virtualization offers us today from a security perspective, we have the following general solution options:
- Hypervisor-based security solutions which may apply policy as a function of the virtual-NIC card of the workloads it protects.
- Extensions of virtual-networking (i.e. switching) solutions that enable traffic steering and some policy enforcement that often depend upon…
- Virtual Appliance-based security solutions that require manual or automated provisioning, orchestration and policy application in user space that may or may not utilize APIs exposed by the virtual networking layer or hypervisor
There are tradeoffs across each of these solutions; scale, performance, manageability, statefulness, platform dependencies, etc. There simply aren’t many platforms that natively offer security capabilities as a function of service delivery that allows arbitrary service definition with consistent and uniform ways of describing the outcome of the policies at these various layers. I covered this back in 2008 (it’s a shame nothing has really changed) in my Four Horsemen Of the Virtual Security Apocalypse presentation.
As I’ve complained for years, we still have 20 different ways of defining how to instantiate a five-tupule ACL as a basic firewall function.
Out of the Darkness…
The promise of SDN truly realized — the ability to separate the control, forwarding, management and services planes — and deploy security as a function of available service components across overlays and underlays, means we will be able to take advantage of any of these models so long as we have a way to programmatically interface with the various strata regardless of whether we provision at the physical, virtual or overlay virtual layer.
It’s truly exciting. We’re seeing some real effort to enable true security service delivery.
When I think about how to categorize the intersection of “SDN” and “Security,” I think about it the same way I have with virtualization and Cloud:
- Securing SDN (Securing the SDN components)
- SDN Security Services (How do I take security and use SDN to deliver security as a service)
- Security via SDN (What NEW security capabilities can be derived from SDN)
There are numerous opportunities with each of these categories to really make a difference to security in the coming years.
The notion that many of our network and security capabilities are becoming programmatic means we *really* need to focus on securing SDN solutions, especially given the potential for abuse given the separation of the various channels. (See: Software Defined Networking (In)Security: All Your Control Plane Are Belong To Us…)
Delivering security as a service via SDN holds enormous promise for reasons I’ve already articulated and gives us an amazing foundation upon which to start building solutions we can’t imagine today given the lack of dynamism in our security architecture and design patterns.
Finally, the first two elements give rise to allow us to do things we can’t even imagine with today’s traditional physical and even virtual solutions.
I’ll be starting to highlight really interesting solutions I find (and am able to talk about) over the next few months.
Security enabled by SDN is going to be huge.