Improving distribution network utilization in Optical Flow Switching

Optical Flow Switching (OFS) is an end-to-end optical circuit oriented network in which optical circuits are created on demand to directly connect pairs of end-users. Circuits are established across three network segments: the access (distribution), the metro and the wide area network. Once the circuit is reserved, the end-user can then fully utilize the optical channel for large data transfers using efficient and specially designed transport protocols. Scheduling of optical flow transmissions (i.e., optical circuit set up and tear down operations) is a critical component of OFS as resources across the three network segments must be lined up and synchronized to form the end-to-end circuit. The current scheduling solution [1], [2] is designed to be simple and efficient in achieving high utilization of both WAN and Metro optical channels. Its downside is that the distribution network channel utilization must remain low. The contribution of this paper is to improve the OFS scheduling procedure in such a way that medium-high utilization of the distribution network is attainable too. This objective is achieved by adding moderate complexity to the original optical flow scheduling and signaling procedure in order to retain the scalability property of the same. With the proposed extension of the OFS scheduler, the distribution network channel utilization is increased manyfolds.