A vision of photonic network in 2020 is presented, which envisages 'smart photonic cloud' in the Big Data era. The smart photonic cloud is referred to as an atmosphere which serves as a universal infrastructure, providing with connectivities to machine-to-machine communications such as networked high-performance computing and intra- and inter data center networks. To cope with strong demands for network virtualization without any physical and logical constraint, its photonic layer 2 virtualization will becomes feasible, which differentiates from the conventional one in terms of the number of slices and the dynamic range of the bandwidth of each slice. For the starter, the guiding principle and the objectives of the vision will be addressed. Next, three 'Ss' key enabling technologies, including smart photonic networking, synthetic transport platform, and scale-free photonics will be presented. A key building block to the above three enabling technologies is the photonic network processor, which can synthesize desired functions of the switch node and the transmission link. The photonic network processor leverages on a recent progress of digital signal processing for coherent optical transmission systems an optical interconnect based upon silicon photonics, and it allows software-defining its functions.