Optical / SDN x-Haul Network

A unique, optical front/mid/back (x) – haul network in COSMOS enables the investigation of new high speed and low latency networking techniques to support emerging and future wireless technologies and applications. The x-haul network builds on the optical networking testbed developed in the NSF Center for Integrated Access Networks (CIAN) Engineering Research Center (ERC). The proposed x-haul network uses wavelength division multiplexing (WDM) with wavelength switching in colorless, reconfigurable optical add-drop multiplexers (ROADM) to enable a wide range of topologies with different size front-haul, mid-haul, and back-haul networks. An SDN control plane further gives users the ability to configure the network and experiment with fiber wireless SDN control and virtualized network functions within the edge cloud.

(a) COSMOS' core optical switching architecture and the switching architecture of a large node, and (b) COSMOS' core optical switching and data center at Columbia computing research facilities (CRF).

SDN Control

The SDN framework used in the COSMOS testbed integrates native and agent-based control of both wired and wireless resources, allowing SDN experiments to implement application driven control of the full set of optical and data networking technologies, as well as radio resource parameters such as power levels and frequency. The COSMOS software framework and testbed control and management software makes it possible to completely decouple radio access technologies from current core network protocol standards such as 3GPP, essentially providing the user with native layer 2 access to all of the network and radio components. Further, the SDN framework supports virtualization which allows for logical separation of the same radio or network resource into multiple distinct networks with their own topology and routing protocol. The SDN/open base station approach has been validated extensively in the ORBIT testbed with various radio access technologies including WiFi, LTE, WiMax and experimental SDR. The open network operating system (ONOS) platform and RYU open flow controllers will be used as standard platforms for SDN and NFV experimentation -due to their ease of use for the research community. Recent multi-tenant controller methods will also be used to allow for different experiments to run unique SDN controllers simultaneously.

[1] T. Chen, J. Yu, A. Minakhmetov, C. Gutterman, M. Sherman, S. Zhu, S. Santaniello, A. Biswas, I. Seskar, G. Zussman, and D. Kilper, “A software-defined programmable testbed for beyond-5G optical-wireless experimentation at city-scale”, IEEE Network, Special Issue on Next-Generation Optical Access Networks to Support Super-Broadband Services and 5G/6G Mobile Networks, vol. 36, no. 2, pp. 90-99, Mar./Apr. 2022. [download]
[2] A. Minakhmetov, C. Gutterman, T. Chen, J. Yu, C. Ware, L. Iannone, D. Kilper, and G. Zussman, “Experiments on cloud-RAN wireless handover using optical switching in a dense urban testbed,” in Proc. OSA OFC’20, Th2A.25, 2020. [download]
[3] J. Yu, C. Gutterman, A. Minakhmetov, M. Sherman, T. Chen, S. Zhu, G. Zussman, I. Seskar, and D. Kilper, “Dual use SDN controller for management and experimentation in a field deployed testbed,” in Proc. OSA OFC’20, T3J.3, 2020. [download]

[4] C. Gutterman, A. Minakhmetov, J. Yu, M. Sherman, T. Chen, S. Zhu, I. Seskar, D. Raychaudhuri, D. Kilper, and G. Zussman, “Programmable optical x-haul network in the COSMOS testbed,” in Proc. IEEE ICNP’19 Workshop Midscale Education and Research Infrastructure and Tools (MERIT), 2019. [download]

[5] J. Yu, T. Chen, C. Gutterman, S. Zhu, G. Zussman, I. Seskar, and D. Kilper, “COSMOS: Optical architecture and prototyping,” in Proc. OSA OFC’19, M3G.3 (invited), 2019. [download] [slides]