Architecture for Overlay Virtual Sub-Network Interconnection An virtualized overlay network may be divided into several subnets for the reasons of geographical location, management, or using different technologies being used. For example, different customer have their own preference. But all these subnets need to work together to provide an end-to-end connectionif in a virtual network, An extended architecture of the NVO3 and propose a new component to provide the connection fucntion are introduced in this document.