It is shown that, particularly for terrestrial cellular telephony, the interference-suppression feature of CDMA (code division multiple access) can result in a many-fold increase in capacity over analog and even over competing digital techniques. A single-cell system, such as a hubbed satellite network, is addressed, and the basic expression for capacity is developed. The corresponding expressions for a multiple-cell system are derived. and the distribution on the number of users supportable per cell is determined. It is concluded that properly augmented and power-controlled multiple-cell CDMA promises a quantum increase in current cellular capacity. >

On the capacity of a cellular CDMA system

The term photonic crystals appears because of the analogy between electron waves in crystals and the light waves in artificial periodic dielectric structures. During the recent years the investigation of one-, two-and three-dimensional periodic structures has attracted a widespread attention of the world optics community because of great potentiality of such structures in advanced applied optical fields. The interest in periodic structures has been stimulated by the fast development of semiconductor technology that now allows the fabrication of artificial structures, whose period is comparable with the wavelength of light in the visible and infrared ranges.

http://ieeexplore.ieee.org/iel5/6354/16969/00781867.pdf

Photonic crystals

In this paper, we review the background and state-of-the-art of big data. We first introduce the general background of big data and review related technologies, such as could computing, Internet of Things, data centers, and Hadoop. We then focus on the four phases of the value chain of big data, i.e., data generation, data acquisition, data storage, and data analysis. For each phase, we introduce the general background, discuss the technical challenges, and review the latest advances. We finally examine the several representative applications of big data, including enterprise management, Internet of Things, online social networks, medial applications, collective intelligence, and smart grid. These discussions aim to provide a comprehensive overview and big-picture to readers of this exciting area. This survey is concluded with a discussion of open problems and future directions.

Big Data: A Survey

Recent technological advancements have led to a deluge of data from distinctive domains (e.g., health care and scientific sensors, user-generated data, Internet and financial companies, and supply chain systems) over the past two decades. The term big data was coined to capture the meaning of this emerging trend. In addition to its sheer volume, big data also exhibits other unique characteristics as compared with traditional data. For instance, big data is commonly unstructured and require more real-time analysis. This development calls for new system architectures for data acquisition, transmission, storage, and large-scale data processing mechanisms. In this paper, we present a literature survey and system tutorial for big data analytics platforms, aiming to provide an overall picture for nonexpert readers and instill a do-it-yourself spirit for advanced audiences to customize their own big-data solutions. First, we present the definition of big data and discuss big data challenges. Next, we present a systematic framework to decompose big data systems into four sequential modules, namely data generation, data acquisition, data storage, and data analytics. These four modules form a big data value chain. Following that, we present a detailed survey of numerous approaches and mechanisms from research and industry communities. In addition, we present the prevalent Hadoop framework for addressing big data challenges. Finally, we outline several evaluation benchmarks and potential research directions for big data systems.

Toward Scalable Systems for Big Data Analytics: A Technology Tutorial

Data centers are experiencing an exponential increase in the amount of network traffic that they have to sustain due to cloud computing and several emerging web applications. To face this network load, large data centers are required with thousands of servers interconnected with high bandwidth switches. Current data center networks, based on electronic packet switches, consume excessive power to handle the increased communication bandwidth of emerging applications. Optical interconnects have gained attention recently as a promising solution offering high throughput, low latency and reduced energy consumption compared to current networks based on commodity switches. This paper presents a thorough survey on optical interconnects for next generation data center networks. Furthermore, the paper provides a qualitative categorization and comparison of the proposed schemes based on their main features such as connectivity and scalability. Finally, the paper discusses the cost and the power consumption of these schemes that are of primary importance in the future data center networks.

A Survey on Optical Interconnects for Data Centers

In this article we review the growing trend of warehouse-scale mega-datacenter computing, the Internet transformation driven by mega-datacenter applications, and the opportunities and challenges for fiber optic communication technologies to support the growth of mega-datacenter computing in the next three to four years.

Fiber optic communication technologies: What's needed for datacenter network operations

Passive optical network (PON) technologies have become an important broadband access technology as a result of the growing demand for bandwidth-hungry video-on-demand applications. Written by the leading researchers and industry experts in the field, this book provides coherent coverage of networking technologies, fiber optic transmission technologies, as well as the electronics involved in PON system development.Features:* An in-depth overview of PON technologies and the potential applications that they enable* Comprehensive review of all major PON standards and architecture evolutions, as well as their pros and cons* Balanced coverage of recent research findings with economic and engineering considerations* Presents system issues of protocols, performance, management and protection* Extensive references to standards and research materials for further studiesThis book provides an authoritative overview of PON technologies and system requirements and is ideal for engineers and managers in industry, university researchers, and graduate students. *Balances treatment of the optical technologies with systems issues such as protocols, performance, management and protection*Covers latest developments in WDM-PONS, protection switching, dynamic bandwidth allocation*Practical coverage with a chapter on PON applications and deployment*Case studies on implementing PONs

Passive Optical Networks: Principles and Practice

We review the growing need for optical interconnect bandwidth in data center networks, and the opportunities and challenges for wavelength division multiplexing (WDM) to sustain the “last 2km” bandwidth growth inside data center networks.

/pdf/scaling-optical-interconnects-in-datacenter-networks-3vyel90yie.pdf

Scaling Optical Interconnects in Datacenter Networks Opportunities and Challenges for WDM

We demonstrate a novel balanced differential optical transmitter for spectrally encoded optical code-division multiple-access (CDMA) systems. The proposed structure is suitable for making optical signaling bipolar using complementary spectral encoding. An optical CDMA link with a pair of programmable transmitter and receiver is tested at the OC-3 transmission speed (155 Mb/s) for single-channel transmission. Unmatched code rejection is also demonstrated.

/pdf/experimental-demonstration-of-bipolar-optical-cdma-system-58batf76hy.pdf

Experimental demonstration of bipolar optical CDMA system using a balanced transmitter and complementary spectral encoding

Passive optical networks (PONs) have been widely used in access networks and are today the access technology of choice for operators, especially when they need to build new infrastructure. Significant effort has been put in place across the years to scale the speed of passive optical networks. The super-PON concept has also been proposed in order to scale reach and customer aggregation of PONs. However, it did not produce any standardization efforts nor significant commercial deployments. In November 2018, the IEEE 802.3 Working Group formed the P802.3cs “Super-PON” Task Force to standardize a flavor of super-PON able to support an increased optical reach of up to 50 km and an expanded customer coverage of up to 1024 customers per fiber over a passive optical distribution network. A project with near identical objectives was later started in ITU-T Q2/SG15. This paper presents the latest updates from these industry standardization efforts, with special attention to the activity of the IEEE P802.3cs Task Force, and the technical reasoning behind some of the key decisions that have been made.

Cedric F. Lam

Papers

Fiber optic communication technologies: What's needed for datacenter network operations

Passive Optical Networks: Principles and Practice

Scaling Optical Interconnects in Datacenter Networks Opportunities and Challenges for WDM

Experimental demonstration of bipolar optical CDMA system using a balanced transmitter and complementary spectral encoding

Super-PON: an evolution for access networks [Invited]