Virtual Tenant Networking (VTN), solves two important challenges in software-defined networking. These are multi-tenancy and service chaining. Let us first understand what these challenges are. Then we will see how VTN solves these problems.
One of the key concepts in OpenStack, or for that matter, any cloud infrastructure platform, is multi-tenancy. The definition of tenants varies based on the usage of cloud. Tenants could be organizations that allow one or more employees to make use of cloud platforms. While such an organization is considered a tenant, the employees are called users. For privacy and security reasons, it is important to isolate the data traffic of one tenant from another. Therefore, traffic isolation is a key element of cloud and software-defined networking.