Cloud-to-Cloud Connectivity Becomes Elastic

Editor’s note: This article is by Douglas Freimuth, Senior Technical Staff Member and Master Inventor at IBM Research.

The true power of cloud computing is in its ability to connect between clouds and share resources and compute power. Clouds make large cloud-to-cloud data transfers for critical administrative functions like data center backups and workload balancing. But a typical private cloud can also connect to a public cloud to access a specific service or type of data to create a “hybrid” cloud. All of that data sharing takes networks – and bandwidth. My team, along with AT&T and Applied Communication Sciences, funded by the DARPA CORONET program, created the technology to make cloud-to-cloud connectivity “elastic” in order to make using the cloud (and paying for that usage) more flexible. Not every service, at every moment of the day, needs peak network availability, so why have the volume turned up all the time? 

Part of the reason for today’s “always on” approach is to always have a secure, reliable network for clouds to connect and operate. Making the bandwidth flexible means being able to adjust the bandwidth on existing connections, which in turn requires making extremely fast decisions, using data center software, about adjustments between cloud-to-cloud connections. With network carriers moving their hardware to software on the cloud, elastic scaling will become commercially available. For example, moving the network infrastructure that manages our smartphone data from a physical box to virtualized software in the cloud can help make elastic connectivity possible – and less expensive for the carrier.

What this partnership has shown in a proof of concept, and now wants to deliver commercially, is a cloud system that monitors and automatically scales the network up or down as applications need. It works by the cloud data center sending a signal to a network controller that describes the bandwidth needs, and which cloud data centers need to connect. The key technology in the cloud IBM will provide is the intelligent orchestration capability that knows when and how much bandwidth to request and between which clouds. The cloud data center orchestrator will continue to get more intelligent in its utilization of the network. Longer term an application on your smart phone might be smart enough to request bandwidth from the network controller.

Today, a truck drives out to install new network components and administrators set up the Wide Area Network connectivity. Physical equipment has to be installed and configured if you want to turn up a WAN signal. We could do all that virtually by using intelligence in the cloud to request bandwidth from pools of network connectivity when needed by an application. When the peak requirement has been met, the cloud can signal the network carrier to release available bandwidth back to the pool.

The difference in set up time between today’s cloud-to-cloud networks, to what we have demonstrated, is days or months versus seconds.

Going from always on to always elastic

To make this all work, we demonstrated a cloud platform running in the cloud data center that manages connections and has the intelligence to make fast decisions to signal a controller in the core network for connectivity at the right time (to make the cloud-to-cloud connection elastic). Then, our partners’ controller orchestrates the requests from our cloud to ensure the requests get to the correct layer in the network. The carriers will provide a multi-layer network with different bandwidth capabilities to service different request from the cloud, such as a request to synchronize a critical application database so that a smartphone user gets up-to-the-moment information, or a full data center backup in the event of a catastrophic event.

The connection request might be set up on an IP network, sub-wavelength or possibly a full wavelength layer for demanding applications depending on the bandwidth requested. Wavelength in this context means optical carrier signals multiplexed over an optical fiber. Each wavelength represents a high bandwidth connection to carry our application data. Those wavelengths can be sub-divided to carry lower bandwidth traffic like a video stream to a mobile device. In the instances of full wavelength requests, all parties involved might utilize a specialized protocol to dynamically set up a high bandwidth service in order to set up the proper routing.

Making cloud-to-cloud computing elastic over WAN augments everything that’s already great about the cloud. Businesses spend less because of more effective sharing of network resources, enabled by virtualized hardware. Operating costs drop because of automated processes controlled by cloud - and network-level orchestrators. Businesses that move to set up cloud-to-cloud connections via WAN will notice further cost savings and faster service setup and delivery.

For you and me, as individuals, more dynamic cloud computing means new applications we never dreamed could be delivered over a network – or applications we haven’t even dreamed of yet.

Douglas M. Freimuth is a Senior Technical Staff Member and Master Inventor in the Cloud Based Networking group at the IBM Thomas J. Watson Research Center where he has focused on the research, design and development of server networking technologies. He is a co-author of the IO Virtualization (IOV) specifications in the PCI SIG. He has also participated in the Distributed Management Task Force (DMTF) for activities related to deployment of Virtual Machines and cloud networks. Doug has 60+ disclosures and patents in the domain of cloud networking, and has also published related papers, developed products and contributed to open source.


  1. Excellent blog on right scaling the network and cloud resources !

  2. Dear Douglas,

    Thank you for this insight, very interesting. I'd like to read more about the details - have you published an according paper?

    Best regards, Alex