Novel virtual OCS in OPS data center networks

This paper proposes a novel virtual optical circuit switching (VOCS) scheme for data center networks where short flows are transmitted via optical packet switching (OPS), while long flows with reliability requirement are transmitted via VOCS. VOCS preserves the advantage of optical circuit switching (OCS) for reliable communication, while it overcomes the disadvantage of OCS in terms of low link utilization. In the VOCS/OPS scheme, idle periods of the virtual circuits can be used by OPS, which thus enhances the overall performance. Simulations on a 6-dimensional torus topology data center network with 4096(=4⁶) nodes are conducted with the following observations: (1) OPS is almost not affected with the introduction of quite a large number (i.e., 3800) of virtual circuits. (2) VOCS has much less impact on the performance of OPS, compared to OCS. (3) The VOCS flow length has little impact on the overall performance.