Building Programmable Wireless Networks: An Architectural Survey

In recent times, there have been a lot of efforts for improving the ossified Internet architecture in a bid to sustain unstinted growth and innovation. A major reason for the perceived architectural ossification is the lack of ability to program the network as a system. This situation has resulted partly from historical decisions in the original Internet design which emphasized decentralized network operations through co-located data and control planes on each network device. The situation for wireless networks is no different resulting in a lot of complexity and a plethora of largely incompatible wireless technologies. The emergence of "programmable wireless networks", that allow greater flexibility, ease of management and configurability, is a step in the right direction to overcome the aforementioned shortcomings of the wireless networks. In this paper, we provide a broad overview of the architectures proposed in literature for building programmable wireless networks focusing primarily on three popular techniques, i.e., software defined networks, cognitive radio networks, and virtualized networks. This survey is a self-contained tutorial on these techniques and its applications. We also discuss the opportunities and challenges in building next-generation programmable wireless networks and identify open research issues and future research directions.Comment: 19 page

Exploiting programmable architectures for WiFi/ZigBee inter-technology cooperation

The increasing complexity of wireless standards has shown that protocols cannot be designed once for all possible deployments, especially when unpredictable and mutating interference situations are present due to the coexistence of heterogeneous technologies. As such, flexibility and (re)programmability of wireless devices is crucial in the emerging scenarios of technology proliferation and unpredictable interference conditions. In this paper, we focus on the possibility to improve coexistence performance of WiFi and ZigBee networks by exploiting novel programmable architectures of wireless devices able to support run-time modifications of medium access operations. Differently from software-defined radio (SDR) platforms, in which every function is programmed from scratch, our programmable architectures are based on a clear decoupling between elementary commands (hard-coded into the devices) and programmable protocol logic (injected into the devices) according to which the commands execution is scheduled. Our contribution is two-fold: first, we designed and implemented a cross-technology time division multiple access (TDMA) scheme devised to provide a global synchronization signal and allocate alternating channel intervals to WiFi and ZigBee programmable nodes; second, we used the OMF control framework to define an interference detection and adaptation strategy that in principle could work in independent and autonomous networks. Experimental results prove the benefits of the envisioned solution

The Question of Spectrum: Technology, Management, and Regime Change

There is general agreement that the traditional command-and-control regulation of radio spectrum by the FCC (and NTIA) has failed. There is no general agreement on which regime should succeed it. Property rights advocates take Ronald Coase's advice that spectrum licenses should be sold off and traded in secondary markets, like any other assets. Commons advocates argue that new technologies cannot be accommodated by a licensing regime (either traditional or property rights) and that a commons regime leads to the most efficient means to deliver useful spectrum to the American public. This article reviews the scholarly history of this controversy, outlines the revolution of FCC thinking, and parses the question of property rights vs. commons into four distinct parts: new technology, spectrum uses, spectrum management, and the overarching legal regime. Advocates on both sides find much to agree about on the first three factors; the disagreement is focused on the choice of overarching regime to most efficiently and effectively make spectrum and its applications available to the American public. There are two feasible regime choices: a property rights regime and a mixed licensed/commons regime subject to regulation. The regime choice depends upon four factors: dispute resolution, transactions costs, tragedies of the commons and anticommons, and flexibility to changing technologies and demands. Each regime is described and analyzed against these four factors. With regard to pure transactions costs, commons may hold an advantage but it appears quite small. For all other factors, the property rights regime holds very substantial advantages relative to the mixed regime. I conclude that the choice comes down to markets vs. regulation as mechanism for allocating resources.