For the purpose of projecting future macroscopic Internet traffic, we have analyzed historical U.S. and global Internet traffic volumes previously reported for 1990 to the present. The empirical long-term traffic trends are characterized by growth rates that have generally been decreasing over time, and so are not adequately described as exponential growth. Based on regression analyses, we also conclude that the decreasing growth rates are not well represented by the saturation characteristic of the logistic function alone. However, we find the observed traffic data are well reproduced over ranges spanning more than six orders of magnitude of traffic volume and a period of 17 years by a hyperbolic dependence of the compound annual growth rate on time. Using a semi-empirical hyperbolic function to model the growth rate we have carried out linearized regression analyses of a combination of historical and near-term traffic forecasts to project macroscopic Internet traffic to 2020 for several geo-economic regions, market segments, and application categories. In contrast to the decade of 2000–2010 when global Internet traffic grew more than 100-fold, the projections indicate that over the decade 2010–2020 the global wireline Internet traffic will grow approximately 16 times larger to approach 250 exabytes per month and the global mobile Internet traffic will grow approximately 150 times larger to approach 40 exabytes per month. The projections also indicate that over the decade the compound annual growth rate of global wireline Internet traffic will decrease from approximately 45 percent to 25 percent per year and the growth rate of global mobility Internet traffic will decrease from approximately 170 percent to 30 percent per year. By considering both the historical trends and near-term forecasts, our analyses and projections call attention to those traffic categories for which estimates of future Internet traffic may carry lesser or greater uncertainty.

Dramatically increasing telecommunication equipment bandwidth motivates exploration of new technologies for backplane implementation. Hence, it is necessary to consider optical backplane implementations for realizing petabit/s switches. Current optical backplane implementations usually guide the light from source to destination with embedded fibers. In this paper we present a new implementation variant for an optical backplane. wherein free space is used as the optical signal medium. This realization just requires fixed mirrors in the rear of the line cards and thus the solution is very cost-effective. The transmitter and receiver are realized using high-speed lasers and photodiodes, and each individual link can transport 25 Gb/s of traffic. Some experimental results are also presented. As an evolutionary step for increased bandwidth, the paper considers the use of an array of links. In this case, we also evaluate the possibility of implementing the parallel transmitters and receivers in an integrated device, which would further reduce space, power consumption and cost.

Data transmission over multimode fibers has the potential to considerably increase the capacity limit of single-mode fibers by exploiting the spatial dimension. For long-haul systems, mode division multiplexing using one mode per channel in a few-mode fiber requires coherent detection in conjunction with digital multiple input multiple output (MIMO) processing for signal separation. In the following we focus on spatial multiplexing using mode groups rather than spatial modes in standard graded-index multimode fibers. In combination with on-off keying (OOK) modulation and direct detection, these systems might be advantageous for access- and connection-related applications, e.g., for super computer interconnects or in the near metro region at link lengths shorter than about 10 km. In this paper we study the potential of mode groups for mode group division multiplexing (MGDM). Single-mode group transmission experiments at 10 Gb/s per mode group, experimental mode group launching by phase mask, and concepts for passive optical mode demultiplexers are discussed.

Forward error correction (FEC) techniques are essential for optical core and optical access networks. In optical core networks, the emphasis is on high coding gains and extremely low output bit error rates, while allowing decoder realizations to operate at a throughput of 100 Gb/s and above. Optical access networks operate at 10 Gb/s or above and require low-complexity FEC codes with low power consumption. Coherent optical transmission with higher order modulation formats will become mandatory to achieve the high spectral efficiencies required in next-generation core networks. In this paper, we provide an overview of these requirements and techniques, and highlight how coding and modulation can be best combined in optical core networks. We also present guidelines for modulation and low-complexity FEC system design for optical access networks.

Mobile data traffic is increasing exponentially and the ability of mobile broadband (MBB) technologies, such as Long Term Evolution-Advanced (LTE-A), to meet this demand depends on the availability of spectrum beyond that which is currently available to cellular mobile systems. This additional spectrum will be needed even considering the gains that will be delivered by LTE and LTE-A's higher spectral efficiency and the use of cell densification. Allocating and making spectrum available on a global basis is a complex process that is managed by the International Telecommunication Union (ITU) on a worldwide scale. Alcatel-Lucent and the wider mobile industry are working to harmonize this spectrum as much as possible to improve economies of scale for mobile broadband technologies and products. This paper describes the current “spectrum crunch,” the spectrum allocation process, steps being taken to make more effective use of available spectrum, and the challenges in making additional spectrum available for the success of next-generation wireless networks.

With the rapid growth of mobile communication systems, user location is proving to be an important asset for end users, operators, application service providers, enterprises, public safety and law enforcement officials, and others. There are a vast number of applications and use cases that exploit location capabilities, each with a diverse set of needs and requirements in terms of accuracy, latency, and scalability. Long Term Evolution (LTE) technology offers multiple methods for determining and delivering location information. The method chosen must meet and be tailored to the needs of the application and use case for which it is being designed. In this paper, we will discuss location determination and delivery methods in LTE, realizable and simple network architectures necessary to support them, and offer a comparative analysis and recommendations. We will also address representative use cases, their requirements, and solutions.

The huge growth in demand for wireless data, combined with shortages of spectrum, has led to an urgent need for spectral efficiency and cell-edge performance improvements in cellular networks. Macrocells are shrinking in size, and heterogeneous networks are being deployed where small cells and macrocells now share the same spectrum. With these trends in cellular network evolution, out-of-sector interference is becoming a major impediment. Impairments due to interference are especially severe on the uplink, where near-far effects are more likely to be experienced. This paper provides a holistic view of the network-centric cooperation schemes that have emerged as strong candidates for uplink interference management in evolving cellular networks (e.g., networks based on 3GPP Long Term Evolution based air-interface technologies and beyond). In particular, we introduce three novel approaches: network multiple input multiple output (MIMO), which carries out joint multi-antenna signal processing across sectors; network interference cancellation engine (NICE) which opportunistically cancels dominant interferers that have already been decoded at neighboring sectors and decreases backhaul overhead by one to two orders of magnitude; and a hybrid approach which combines the strengths of both network MIMO and NICE in an attempt to achieve further spectral efficiency without incurring huge backhaul overhead. Several considerations of both theoretical and practical significance (overhead, latency) related to these approaches are discussed, and simpler variants that may apply in the context of heterogeneous networks are also considered. Quantitative investigations of these network-centric cooperation schemes in realistic operating environments show that substantial improvement may be achieved in average and cell-edge spectral efficiency.

Video is expected to be the dominant application by traffic volume over mobile networks in the near future. Mobile network operators are deploying video optimization techniques to enhance the user experience and network utilization for video delivery. Video optimization is typically “out-of-network” and includes techniques such as transcoding, transrating, time shifting and pacing that are implemented outside of mobile radio access and core networks. However, such techniques cannot easily exploit information about real time cell congestion and radio conditions for the video terminals because it is difficult to obtain such information from the radio access network. We propose a novel “in-network” video optimization technique, named Adaptive Guaranteed Bit Rate (AGBR), for HTTP-based Adaptive Streaming (HAS) video. This optimization technique is implemented at the base station and can thus exploit knowledge of the radio and congestion conditions. With only limited knowledge of the video stream properties or content, AGBR works by adjusting the throughput delivered to the different HAS clients that in turn adjust the video quality they request. The optimization algorithm maximizes aggregate quality across multiple video flows served by the base station without starving data clients, thereby improving the overall quality of experience. We demonstrate through extensive analytical modeling and simulations that AGBR can adapt to changing network conditions to support more video sessions at an acceptable quality than alternative algorithms, while enforcing fairness among all users competing for resources within a sector.

Heterogeneous networks (HetNets) are a powerful solution to handle the rapidly increasing demand for mobile broadband bandwidth and are a key concept of Alcatel-Lucent's lightRadioTM strategy. HetNets consist of small cells embedded in a macrocellular network and enable flexible and scalable capacity enhancements. The first part of this paper discusses basic HetNet-specific aspects, e.g., small cell placement and fairness with respect to service quality. We present solutions for cell range expansion of small cells, which enables more user equipment (UEs) to profit from the additional capacity. The second part discusses advanced approaches for interference management optimized for HetNets. We present advanced solutions which exploit the possibilities offered by new Long Term Evolution (LTE)-Advanced features like enhanced inter-cell interference coordination (eICIC) and carrier aggregation (CA). We evaluate the performance of these advanced solutions based on standards compliant downlink (DL) system simulations in different application scenarios and provide recommendations on advanced scheduling strategies.