A dynamic controller to automatically generate layer 3 network connections between devices and/or networks associated with a virtual computing environment in response to a request for such connections is provided such that communications associated with the computing environment may be transmitted between the endpoints. For example, the dynamic controller may connect one or more cloud service provider networks, one or more customer-controlled data centers, one or more customer networks, and the like, based on information provided in a connection request. A layer 3 communication controller may also be instantiated within a core network that manages the flow of communications between the connected networks, such as by translating messages between the connected networks so that messages intended for a connected network may match the supported communication protocols of that network and/or providing one or more security features to the transmitted communications.