In a SDDC, all elements of infrastructure, that is storage, networking, and compute are fully virtualized and delivered as a service. It is described by VMware as "A unified data center platform that provides unprecedented automation, flexibility, and efficiency to transform the way IT is delivered. Compute, storage, networking, security, and availability services are pooled, aggregated, and delivered as software, and managed by intelligent, policy-driven software". An SDDC is the mechanism through which cloud services can be delivered most efficiently. One of the key goals of an SDDC is to build a cloud-based data center. Vendors such as Amazon, Google, IBM, and VMware all have their own set of public cloud services running on an SDDC stack . Yes, now we have a next-generation data center wherein we could pool all physical servers and let applications run according to IT-defined policies.
As the heading suggests, the three pillars of SDDC are shown in the following screenshot:
Let's go through each of them one by one:
In Compute virtualization, CPU and memory are decoupled from physical hardware and each application resides in a software object called a virtual machine. VMware VSphere, Microsoft Hyper-V, Citrix XenServer, Oracle VM are a few examples in that family.
Storage virtualization in a Software Defined Storage (SDS) environment is a hypervisor-based storage abstraction from the heterogeneous model of physical servers. Software that enables an SDS provides most of the traditional storage array features, such as replication, deduplication, thin provisioning, and snapshots. Since this is a completely software-defined storage, we have increased flexibility, ease of management, and cost efficiency. In this way, pooled storage resources can be automatically and efficiently mapped to application needs in a software-defined data center environment. VMware VSAN is a classic example of SDS since it is a distributed layer of software that runs natively as a part of an ESXi hypervisor.
Network virtualization is the third and most critical pillar of a Software Defined Data Center (SSDC) center and gives the full set of Layer 2-Layer 7 networking services such as routing, switching, firewall, load balancing, and QoS at the software layer. Network virtualization is the virtualization of network resources using software and networking hardware that enables faster provisioning and deployment of networking resources. The innovation speed of software is much faster than hardware and the answer for the future is not a hardware-defined data center but a Software Defined Data Center which will let us extend the virtualization layer across physical data centers. What makes Amazon and Google the world's largest data center is the brilliance of Software Defined Data Center. Network virtualization provides a strong foundation by effectively resolving all traditional network challenges to ensure we are getting a fully-fledged SDDC stack. As the cloud consumption model is being rapidly adopted across the industry, the need for on-demand provisioning of compute, storage, and networking resources is greater than ever. Network virtualization decouples the networking and security features from physical hardware and allows us to replicate similar network topology in a logical network.