Tired of the Cloud: A Control Plane

Cloud computing depends on the seamless interaction between multiple types of hardware and software.  For the purpose of this topic, let’s focus exclusively on the hardware aspects of cloud computing.  I will revisit the application aspects in a later post.


If you peel back the onion, what’s the DNA of cloud computing?  The obvious answer is servers, networking, security, and storage equipment.  However, don’t forget about space, power, cooling, cabling, and people.  Whether you build a two-tier or three-tier architecture, the infrastructure looks strikingly similar. 


The datacenter will be filled with racks of servers, top-of-the-rack switches, perhaps I/O off-load appliances, fabric switches, core switches, security appliances, network sniffers, routers, load balancers, storage networking devices, SANs or NAS devices, WAN Accelerators, optical networking equipment, and more.  You will find a combination of Ethernet and Fibre Channel, and perhaps even InfiniBand.  What about throwing hardware based database systems from Teradata, Netezza, Greenplum, and more into the mix?  Let’s not forget that all these systems must be fault tolerant and must be tied to real disaster recovery plans. 


Like a giant jigsaw puzzle, each piece of hardware plays an important role in what the final picture looks like.  Unlike a jigsaw puzzle, there is no real commonality between the pieces.  What about TCP/IP?  For the sake of argument, let’s assume all the above devices are IP addressable.  While each device can be accessed via a single console (that’s a stretch), they all have their own operating systems, user interfaces, and best practices. 


What’s missing is a single control plane across all the devices.  The control plane serves multiple purposes; it manages the individual devices, controls the interaction between multiple devices, and is used by a central brain to manage the entire cloud infrastructure.  Some have called this a “datacenter OS”, but that is usually in reference to server silos and points to an application such as VMware or Xen.  Somehow, we conveniently forget about the underlying hardware that supports all these cloud applications.


For our jigsaw puzzle, servers stand out as the most important yet least integrateable into this new control plane.  One may argue that blade servers and management cards such as Dell’s DRAC or HP iLO fill this void.  However, I believe the lack of a true server control plane is driving Cisco into the DMZ between networking and server manufacturers.  Once servers are brought into the mix, all that is missing is a standardization effort of this control plane.  If you are Cisco, then IOS is the perfect choice.  However, Juniper may prefer JUNOS.   I would prefer an actual or defacto standard and don’t get me started on SNMP.


One final thought on this control plane, it’s not simply a configuration plane.  The control plane must understand the complex relationships between the different pieces of the puzzle.  Furthermore, this control plane stretches beyond the hardware and intersects with applications allowing for true service level guarantees and multi-purpose cloud infrastructures.