Service Competition and Data-Centric Protocols for Internet Access

The Internet evolved in many aspects, from the application to the physical layers. However, the evolution of the Internet access technologies, most visible in dense urban scenarios, is not easily noticeable in sparsely populated and rural areas. In the United States, for example, the FCC identified that 50% of the census blocks have access to up to two broadband providers; however, these providers do not necessarily compete. Additionally, due to the methodology of the study, there is evidence that the number of actual customers without broadband access is higher since the FCC considers the entire block to have broadband if any customer in a block has broadband. Moreover, the average downstream connection bandwidth in the United States is 18.7 Mbps, according to the Akamai State of the Internet report, which places the US in the 10th position in the global rank. It’s worth noting that modern applications such as Ultra High Definition (UHD) video streaming requires a bandwidth of at least 25 Mbps. Newer applications such as virtual reality streaming require at least a 50 Mbps bandwidth. Additionally, urban scenarios are dominated by monopolistic and duopolistic markets, whereby network providers have little incentives to offer innovative services. In this work, we propose an open access network infrastructure along with a novel Internet architecture that allows dynamic economic relationships between users and providers through a marketplace of network services. These economic relationships have a finer granularity than today’s coarse and lengthy contracts, allowing higher competition and promoting innovation in the access market. We develop an agent-based simulator to evaluate our proposed network model and its various competition scenarios. Our simulations show that competition greatly benefits users and applications, creating the necessary incentives for providers to innovate while also benefiting consumers. The trend that resulted in sparsely populated areas lagging of the latest innovations in the access networks is also observed in wireless access networks, where the investments are focused on densely populated areas. Moreover, the rapidly increasing number of mobile devices coupled with the increasingly bandwidth demanding applications are posing a significant challenge to cellular network operators that have to increase OPEX/CAPEX and deal with higher complexity in their networks. The advances in the access technologies that brought higher speeds and lower latency also reduced the area of coverage of cellular base stations. To cope with the increase in traffic, cellular network operators have been deploying more base stations. In addition, cellular providers have adopted “all-you-can-use” price models, which led users to ramp-up their usage, further worsening congestion in the network. To address this issue, we propose a scheme that uses Device-to-Device (D2D) communication along with Information-Centric Networking (ICN) to offload traffic from cellular base stations. Then, we build on this scheme and propose a cross-layer assisted forwarding strategy to enhance communication in the MANET. In D2D communication, users can retrieve content directly from their nearby peers. However, this type of communication poses challenges to the current connection-oriented communication model, as devices can move in and out of the communication range at any time, constantly changing routing state, and nodes are subject to hidden and exposed terminal problems. ICN addresses some of these issues with inherent support for transparent caching and named content retrieval, making the network more resilient to disconnections. Our proposed scheme can offload up to 51.7% of the contents from the backhaul cellular infrastructure when requesting the content from nearby peers first. Finally, we combine the concepts of the marketplace, D2D communication, and ICN to propose a platform for decentralized and opportunistic communication that uses COTS radios to relay packets, extending the reach of the Internet to sparsely populated areas with low cost and without the lengthy contracts from commercial network providers. Our platform can potentially link the remaining part of the population that is not currently connected to the Internet

Scalable base station switching framework for green cellular networks

With the recent unprecedented growth in the wireless market, network operators are obliged not only to find new techniques including dense deployment of base stations (BSs) in order to support high data rate services and high user density, but also to reduce the operating costs and energy consumption of various network elements. To solve these challenges, powering down certain BSs during low-traffic periods, so-called BS sleeping, has emerged as an effective green communications paradigm. While BS sleeping offers the potential to significantly lower energy consumption, it also raises many challenges, since when a BS is switched off, this can lead to, for example, coverage holes, sudden degradation in quality of service (QoS), higher transmit power dissipation in off-cell mobile stations (MSs), an inability to rapidly power up/down equipment and finally, a failure to uphold regulatory requirements. In order to realise greener network designs which both maximise energy savings whilst guaranteeing QoS, innovative BS switching mechanisms need to be developed. This thesis presents a novel BS switching framework which improves energy efficiency (EE) in comparison with existing approaches, while guaranteeing the minimum QoS and seamless services. The major technical contributions in this framework are: i) a new BS to relay station (RS) switching model where certain BSs are switched to RS mode rather than being turned off, firstly using a fixed threshold based switching algorithm utilizing temporal traffic diversity, and ii) then subsequently by means of an adaptive threshold by exploiting the inherently asymmetric traffic profile between cells, i.e., by exploiting both the temporal and spatial traffic diversity; iii) a traffic-and-interference-aware BS switching strategy that considers the impact of inter-cell interference in the decision making process to dynamically determine the best BS set to be kept active for improved EE; and finally iv) a novel scalable multimode BS switching model which enables each BS to operate in different power modes i.e., macro/micro/sleep to explore energy savings potential even at higher traffic conditions. The thesis findings conclusively confirm this new BS switching framework provides significant EE improvements from both BS and MS perspectives, under diverse network conditions and represents a notable step towards greener communications

Potentzia domeinuko NOMA 5G sareetarako eta haratago

Tesis inglés 268 p. -- Tesis euskera 274 p.During the last decade, the amount of data carried over wireless networks has grown exponentially. Several reasons have led to this situation, but the most influential ones are the massive deployment of devices connected to the network and the constant evolution in the services offered. In this context, 5G targets the correct implementation of every application integrated into the use cases. Nevertheless, the biggest challenge to make ITU-R defined cases (eMBB, URLLC and mMTC) a reality is the improvement in spectral efficiency. Therefore, in this thesis, a combination of two mechanisms is proposed to improve spectral efficiency: Non-Orthogonal Multiple Access (NOMA) techniques and Radio Resource Management (RRM) schemes. Specifically, NOMA transmits simultaneously several layered data flows so that the whole bandwidth is used throughout the entire time to deliver more than one service simultaneously. Then, RRM schemes provide efficient management and distribution of radio resources among network users. Although NOMA techniques and RRM schemes can be very advantageous in all use cases, this thesis focuses on making contributions in eMBB and URLLC environments and proposing solutions to communications that are expected to be relevant in 6G

Recent Advances in Wireless Communications and Networks

This book focuses on the current hottest issues from the lowest layers to the upper layers of wireless communication networks and provides "real-time" research progress on these issues. The authors have made every effort to systematically organize the information on these topics to make it easily accessible to readers of any level. This book also maintains the balance between current research results and their theoretical support. In this book, a variety of novel techniques in wireless communications and networks are investigated. The authors attempt to present these topics in detail. Insightful and reader-friendly descriptions are presented to nourish readers of any level, from practicing and knowledgeable communication engineers to beginning or professional researchers. All interested readers can easily find noteworthy materials in much greater detail than in previous publications and in the references cited in these chapters