Optical networking technology can play an important role in realizing cost-effective interconnecting of a wide variety of resources over a highly-distributed computing environment, especially when the cloud solution has to address massive data exchanging and processing. It is known that with the dense wavelength-division multiplexing (DWDM) technology, over 20 Tb/s capacity can be achieved over a single strand of optical fiber. Moreover, since the store-and-forward like electrical processing is minimized, optical transmission and switching usually have very low latencies that are only limited by the transmission distance and physical impairments. In order to facilitate flexible access to the numerous bandwidth of optical fibers, researchers have recently developed a few promising technologies. These ongoing efforts indicate that agile and automatic bandwidth provisioning can be realized for elastic optical networking. For physical transmission, mixed line rate (MLR) and optical orthogonal frequency-division multiplexing (O-OFDM) have been investigated for supporting sub-wavelength bandwidth allocation granularity. In terms of optical switching, optical packet/label/burst switching technologies have been proposed to fulfill the gap between optical bandwidth and client demands. These proposals can make optical bandwidth allocation and switching adapt to the spatial and temporal nature of cloud traffic.

Additionally, optical interconnecting within data-centers is another interesting topic to look into for the convergence of cloud computing and optical networks, since the backplanes of supper-computers and switches/routers have become one of the primary bottlenecks to data transfer. It is known that conventional optical transceiver and modulation technology can be too expensive, bulky and power hungry to support short-reach interconnects within data-centers. Therefore, we have to develop low-power and low-cost solutions for this type of short-reach applications. The optical modulation formats, including non-return-to-zero (NRZ), pulse amplitude modulation (PAM), carrier-less amplitude and phase modulation (CAP), O-OFDM and etc, have recently investigated for this purpose. A few transceivers, such as directly modulated lasers (DMLs), vertical-cavity surface-emitting lasers (VCSELs), reflective semiconductor optical amplifiers (RSOAs) and etc, have been considered for short-reach optical interconnects as well. To make these technologies more cost-effective, photonic integration is an inevitable direction. Moreover, with the support of advanced optical components, multi-mode fiber (MMF) can offer high-speed interconnects within data-centers.

Scope of Contributions
This special issue invites manuscript submissions to explore recent advances and disseminate the state-of-the-art research on optical networks in cloud computing, including all levels of designing and developing, from the device to system and network levels. It will also identify potential research directions that will lead to innovations within this area. We expect the papers of this special issue to serve as valuable references for a large audience from both academia and industry. Original, unpublished contributions and survey/tutorial types of articles will be considered. The topics of interest for the special issue include, but are not limited to:

• Elastic optical networking technologies to support grid or cloud computing
• Optical infrastructures for grid or cloud computing
• Multi-layer, multi-domain designs and optimizations for optical infrastructures of grid or cloud computing
• Routing and path computation algorithms for grid or cloud computing environments
• Resource allocation algorithms in optical grid or cloud computing environments
• Optical network virtualization for grid or cloud computing
• Network reconfiguration and traffic engineering for optical clouds
• Optical network control and management for grid or cloud computing
• Protection and restoration in optical clouds.
• Optical storage networks
• Impact of physical-layer impairments on optical cloud design
• Security in optical clouds
• Optical switching technologies, devices, and architectures for grid or cloud computing
• Digital signal processing technologies for short-reach optical interconnects within data-centers
• Optical interconnects for high-performance computing systems
• Performance analysis of short-reach optical interconnects within data-centers
• Photonic integration for short-reach optical interconnects
• Transceiver technologies for short-reach optical interconnects
• Chip-scale optical data communications
• Field trials, new applications and experiments on convergence of grid and cloud computing and optical networks
• Energy-efficient/green optical clouds

Schedule
Submission Deadline: Apr. 1 2013
Acceptance Notification: Aug. 1 2013
Final Manuscript Due: Sept. 1 2013
Publication: Nov. 2013

Guest Editors
S. J. Ben Yoo
Department of Electrical and Computer Engineering
University of California, Davis
Davis, CA 95616, USA
Email: sbyoo@ucdavis.edu

Zuqing Zhu
School of Information Science and Technology
University of Science and Technology of China
Hefei, Anhui 230027, China
Email: zqzhu@ieee.org

Zhaohui Li
Institute of Photonics Technology
JiĠnan University
Guangzhou, Guangdong 510632, China
Email: tlzh88@jnu.edu.cn

Nicolas Fontaine
Bell Laboratories
Alcatel-Lucent
Holmdel, NJ 07733, USA
Email: nicolas.fontaine@alcatel-lucent.com