Fast WDM Provisioning With Minimum Probe Signals: The First Field Experiments For DC Exchanges
Publication Date: 2/1/2024
Event: Journal of Optical Communications and Networking
Reference: 16(2): 233-242, 2024
Authors: Hideki Nishizawa, NTT Network Innovation Labs; Toru Mano, NTT Network Innovation Labs; Thomas Ferreira de Lima, NEC Laboratories America, Inc.; Yue-kai Huang, NEC Laboratories America, Inc.; Zehao Wang, Duke University; Wataru Ishida, NTT Network Innovation Labs; Masahisa Kawashima, Politecnico di Torino; Ezra Ip, NEC Laboratories America, Inc.; Andrea DAmico, NEC Laboratories America, Inc.; Seiji Okamoto, NTT Network Innovation Labs; Takeru Inoue, NTT Network Innovation Labs; Kazuya Anazawa, NTT Network Innovation Labs; Vittorio Curri, Politecnico di Torino; Gil Zussman, Columbia University; Daniel Kilper, CONNECT Centre; Tingjun Chen, Duke University; Ting Wang, NEC Laboratories America, Inc.; Koji Asahi, NEC Corporation; Koichi Takasugi, NTT Network Innovation Labs
Abstract: There are increasing requirements for data center interconnection (DCI) services, which use fiber to connect any DC distributed in a metro area and quickly establish high-capacity optical paths between cloud services and mobile edge computing and the users. In such networks, coherent transceivers with various optical frequency ranges, modulators, and modulation formats installed at each connection point must be used to meet service requirements such as fast-varying traffic requests between user computing resources. This requires technology and architectures that enable users and DCI operators to cooperate to achieve fast provisioning of WDM links and flexible route switching in a short time, independent of the transceivers implementation and characteristics. We propose an approach to estimate the end-to-end (EtE) generalized signal-to-noise ratio (GSNR) accurately in a short time, not by measuring the GSNR at the operational route and wavelength for the EtE optical path but by simply applying a quality of transmission probe channel link by link, at a wavelength/modulation-format convenient for measurement. Assuming connections between transceivers of various frequency ranges, modulators, and modulation formats, we propose a device software architecture in which the DCI operator optimizes the transmission mode between user transceivers with high accuracy using only common parameters such as the bit error rate. In this paper, we first implement software libraries for fast WDM provisioning and experimentally build different routes to verify the accuracy of this approach. For the operational EtE GSNR measurements, the accuracy estimated from the sum of the measurements for each link was 0.6 dB, and the wavelength-dependent error was about 0.2 dB. Then, using field fibers deployed in the NSF COSMOS testbed, a Linux-based transmission device software architecture, and transceivers with different optical frequency ranges, modulators, and modulation formats, the fast WDM provisioning of an optical path was completed within 6 min.
Publication Link: https://opg.optica.org/jocn/fulltext.cfm?uri=jocn-16-2-233&id=546233