Virtual Tenant Network

By Harpreet Singh Dhillon

Virtual Tenant Network (VTN) is an application, which provides multi-tenant network facility on an existing network infrastructure. The traditional network infrastructure is configured as a silo for each department, which requires huge CAPEX & OPEX cost investment. Every department in an organization needs separate proprietary hardware, which need not be shared with others.

VTN provides a logical abstraction plane, which facilitates complete segregation of the logical plane from the underlying physical infrastructure. VTN divides physical infrastructure into multiple logical parts and maps it to the physical network. This will not only reduce complexity, but also provides better management of resources and brings efficiency in infrastructure. NEC Corporation of America is contributing in VTN project for open daylight.

Architectural Overview

VTN application has been divided into the following two components:

• VTN Manager: It is the plugin that interacts with other networking components to build network for the end user. 
• VTN Coordinator: It is an external application that provides a REST API interface to the end user to build VTN network. The VTN coordinator passes request to VTN manager, which serve the request of end users and build the desired network. 

Fig. - Architecture of VTN

Challenges in Current Infrastructure

• Lack of flexibility and agility: The current network infrastructure does not provide any kind of flexibility across network devices. Due to this limitation, network devices do not support multi-tenancy and the network appliances are running in silo for each department. 
• Complexity: Network is becoming more complex due to large and increasing variety of proprietary hardware appliances provided by various network vendors. 
• Manually intensive management: Provisioning and configuration for network appliances are complex, manually intensive and time-consuming tasks. 
• Huge CAPEX & OPEX investment: Each department requires separate proprietary hardware appliance, which is a huge investment for purchasing of new hardware and resources to manage the infrastructure.

Benefits of VTN

• Reduce Capex: VTN provides multi-tenancy feature on a network infrastructure. Therefore, the same physical infrastructure will be used by multiple departments. This will reduce the need of separate hardware for each department and certainly decrease the Capex investments. 
• Reduce Opex: VTN provides centralized management of network infrastructure through Software Defined Networking and eliminates manual efforts, thus enabling automation in a network. This reduces manpower costs and saves huge opex costs for an organization. 
• Flexibility: The VTN facilitates easy, rapid and dynamic provision for new services in various locations. 
• API support: The VTN supports REST API, which helps the network to integrate with the infrastructure orchestrator layer and automate the entire network provisioning and configuration management. 

Conclusion

The network technology of the present day is very frequently evolving. With the evolution of cloud infrastructure, organizations are facing pressure to cut down their OPEX and CAPEX costs. VTN is the best suited technology, which not only reduces infrastructure costs, but also eliminates the complexity in the existing infrastructure.