To date, three main optical switching technologies have been investigated which resulted in increasing data transfer capabilities for the data center networks. Optical Circuit Switching (OCS): OCS has three distinct steps: links set-up,. To date, three main optical switching technologies have been investigated which resulted in increasing data transfer capabilities for the data center networks. Optical Circuit Switching (OCS): OCS has three distinct steps: links set-up, data transmission and links tear-down. One of the main features of OCS is its two-way reservation process in the. Relying on the flexible-access interconnects to the scalable storage and compute resources, data centers deliver critical communications connectivity among numerous servers to support the housed applications and services. To provide the high-speeds and long-distance communications, the data centers have turned to fiber interconnections. With the s. Dater centers (DCs), consisting of tens thousands of servers connected by large switching networks, provide the infrastructure for online applications and services such as cloud computing, social networks, file storage, and web search. The topology of data center networks (DCNs) plays significant roles in determining the communication bandwidth. Optical switching, as a future-proof solution to overcome the bandwidth bottleneck of electrical switches, has attracted the widespread attention to researchers. Due to the optical transparency, switching the data in the optical domain is independent of the bit-rate and data-format of the traffic. Thus, optical switching supports much higher bandwi. Various optically switched architecture prototypes, based on the above optical switches, have been proposed to demonstrate the potential of optical data center networks. Optical data center networks are mainly classified into two categories based on the switching techniques used, the electrical/optical hybrid scheme, where electrical along with the.