On bandwidth-rich and high-efficient cloud transport networks

The Cloud transport networks are developed all-optically based on wavelength division multiplexing (WDM) technology since it can provide huge transmission bandwidth. Nonetheless, as people are more dependent on the Internet in the daily life, the volume of Internet traffic in the Cloud, such as text or video messages, albums, transactions, etc., are increasing exponentially every year and would lead to massive data migration within the Cloud which requires ultra-high transmission bandwidth that overwhelms WDM. As an alternative, multi-mode communications being demonstrated with space division multiplexing (SDM) are attracting increasing attention. SDM using multi-core multi-mode fibers (MCMFs) in conjunction with the traditional WDM could provide ultrahigh transmission bandwidth. In this paper, we provide the first insight to the MCMF-based transport networks and discuss some key issues, particularly involving the network modeling, the design of reconfigurable optical add/drop multiplexing (ROADM) system, the mechanisms for control plane, and the impact of mode conversion capability on network performance.