Organizations are incorporating public cloud resources into their deployment strategies. The organization may have a cloud-first initiative, or it may use the cloud as determined by the workload but the reality is that an overwhelming number of organizations deploy in a hybrid cloud model where some of the organization’s workloads are in the cloud, and other workloads are on-premises. Many organizations have workloads, that in and of themselves, are hybrid with components running in the cloud and other components running on-premises. The hybrid reality of application deployment is the reason that organizations should move away from the traditional box-by-box approach to networking and toward software-defined networking (SDN).
How Big Cloud Networking Works
When organizations move an application or workload to the cloud, that environment still needs networking. Configuration settings like subnets, route tables, gateways, and security groups all need to be established. Organizations like Amazon AWS, Microsoft Azure and Google Cloud don’t let their customers interact with the physical hardware. Cloud providers create a virtual private cloud (VPC) and assign that to the customer to configure. The networking environment allocates in seconds, and the customer is free to configure the VPC as they see fit. A VPC enables the cloud provider to quickly create an environment for their customers without having to get involved in the minutia of networking hardware configurations.
The hardware behind the VPC is typically white-box switches available from a wide variety of vendors at a fraction of the costs of switches from the major switch providers. The VPC is controlled entirely through software, eliminating the need to configure hardware each time a client is on-boarded. The software spans multiple white box switches (typically numbered in the thousands) and allows managing them centrally.
The Hybrid Problem
The problem is the traditional data center today, does not use a VPC like construct. It uses name brand hardware that sells at a premium. Moving applications back and forth between these different networking worlds is painful. Each time an application or workload moves, changes are required to enable it to run. Since hybrid deployment is the most popular form of cloud adoption, it makes sense to create a networking standard that spans both on-premises and the cloud. Organizations should look for a way to move the VPC concept on-premises.
On-Premises VPC
Like the cloud, software controls the on-premises VPC. The software acts as both a universal network operating system and a network orchestration engine so the on-premises network can programmatically provision the physical network components. The data center, like the cloud data center, would be free to use white box switches to lower acquisition costs. Since it is software, the same orchestration component can be placed in the cloud, enabling IT to control both on-premises and cloud-based networks in the same manner. At that point, data and applications can seamlessly move between cloud and on-premises since, from a networking perspective, there is no difference.
Conclusion
In this blog series, Storage Switzerland has articulated the “why” behind SDN. While network infrastructures are typically slow to evolve, moving to SDN has potentially the most significant payoff of any of the software-defined data center initiatives. Once SDN is understood, it has benefit for both the storage team and the network teams. Even organizations developing or implementing a cloud strategy can derive real benefits from SDN architecture. The key is to move on it now and start the conversion to a software-defined future.
George Crump is the Chief Marketing Officer at VergeIO, the leader in Ultraconverged Infrastructure. Prior to VergeIO he was Chief Product Strategist at StorONE. Before assuming roles with innovative technology vendors, George spent almost 14 years as the founder and lead analyst at Storage Switzerland. In his spare time, he continues to write blogs on Storage Switzerland to educate IT professionals on all aspects of data center storage. He is the primary contributor to Storage Switzerland and is a heavily sought-after public speaker. With over 30 years of experience designing storage solutions for data centers across the US, he has seen the birth of such technologies as RAID, NAS, SAN, Virtualization, Cloud, and Enterprise Flash. Before founding Storage Switzerland, he was CTO at one of the nation's largest storage integrators, where he was in charge of technology testing, integration, and product selection.
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Excellent post, George. IT managers should seriously take more time understanding the benefits of SDN, particularly DNS functionality and zones. Not all public cloud providers support and/or implement the same.