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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 transceiver’s 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.
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All oxide plasmon-assisted optical modulator
Data usage across the internet is growing exponentially, fueled primarily by the move to cloud computing and penetration of streaming services into developing countries. To address the growing energy needs of data centers, we propose an all oxide plasmon assisted electro-optic modulator, which features enhanced light-matter interaction, and compact sizes as seen in plasmonic modulators while at the same time maintaining low insertion losses, as seen in photonic modulators. This is achieved by utilizing a device design that selectively engages and disengages the lossy plasmonic component, as the device switches from low transmission to high transmission modes.
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- Award ID(s):
- 1808928
- PAR ID:
- 10507320
- Editor(s):
- Subramania, Ganapathi S.; Foteinopoulou, Stavroula
- Publisher / Repository:
- SPIE
- Date Published:
- ISBN:
- 9781510637283
- Page Range / eLocation ID:
- 61
- Format(s):
- Medium: X
- Location:
- Online Only, United States
- Sponsoring Org:
- National Science Foundation
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