Cloud Native Data Center Networking

Chapter 6. Network Virtualization

It’s what we come for, to gawk at all those layers, exposed.

Wendy Barker

Cloud computing is possible only because of the technologies that enable resource virtualization. If you’re going to have multiple virtual endpoints share a physical network, but different virtual endpoints belong to different customers, the communication between these virtual endpoints also need to be isolated from one another. In other words, network is a resource, too, and network virtualization is the technology that enables the sharing of a common physical network infrastructure. In the data center, the use of network virtualization is not limited to cloud computing. This chapter therefore aims to acquaint the network engineer or architect with this fundamental technology.

This chapter helps a network engineer or architect answer the following questions:

• What is network virtualization?

• What are the uses of network virtualization?

• What are the different choices in network virtualization?

• What are the control-plane choices for network virtualization?

• How does bridging and routing work with VXLAN?

What Is Network Virtualization?

Network virtualization enables a network operator to carve a single physical network into multiple isolated, virtual networks. The concept is similar to server virtualization. In server virtualization, the compute element consisting of a CPU, memory, and I/O interfaces is carved into multiple virtual compute elements. Each virtual ...