The rapid development of the cloud computing industry in recent years has led Baidu, China's largest search engine, to pioneer open cloud services in addition to its core search business and services such as big data analysis. The variety of internal services and complex individual requirements of open cloud challenge Baidu to maintain satisfactory IDC interconnection bandwidth and traffic scheduling between IDCs on its optical transport network. Currently, Baidu's metro optical transport system tends to use point-to-point interconnections between IDCs. All inter-IDC traffic must therefore be forwarded by the super IDC core switch. Since all Baidu services are inter-IDC, the load on the core switch located in the super IDC is heavy, adversely effecting traffic scheduling between IDCs.
Drawing on a deep understanding of Baidu's services and network architecture, Huawei custom-built an IDC optical transport network solution based on T-SDN to help Baidu explore new network operating modes. Huawei T-SDN's bypass function for data traffic between IDCs allows Baidu services of different granularities to be transmitted at different optical network layers. For example, low-granularity services can be scheduled at the OTN layer while high-granularity services can be transparently transmitted over wavelengths. The bypass function reduces traffic load on core switches, and satisfies the complex individual requirements of Baidu's internal and open cloud services. In addition, Huawei's T-SDN solution provides both real-time and scheduled service provisioning, as well as adjustment of transmission pipes and transmission pipe bandwidth. Flexible E2E service scheduling better handles both ordered and burst transmission requirements between IDCs.