A method of utilizing the same hardware network interface card (NIC) in a gateway of a datacenter to communicate datacenter tenant packet traffic and packet traffic for a set of applications that execute in the user space of the gateway and utilize a network stack in the kernel space of the gateway. The method sends and receives packets for the datacenter tenant packet traffic through a packet datapath in the user space. The method sends incoming packets from the NIC to the set of applications through the datapath in the user space, a user-kernel transport driver connecting the kernel network stack to the datapath in the user space, and the kernel network stack. The method receives outgoing packets at the NIC from the set of applications through the kernel network stack, the user-kernel transport driver, and the data path in the user space.