No abstract

Due to the Internet's commercialized ISP structure, inter-domain routing is perceived as more of a commercial service (and market decision) instead of an optimization problem subject to purely technical criteria. In this perspective, routing could be defined as a service which matches perishable resources to requested level of service demands. This diversity in demanded services and proliferation of diverse set of existing and emerging applications cannot be responded by a single mindset of priorities, limited set of metrics or protocol characteristics. Instead, we propose a contract-based routing service architecture which allows manageable dynamism or routing protocol characteristics. By considering routing as a contracted service, network traffic can be treated as "value flows" rather than bare bits. Such value-based treatment of routing will significantly help improving inter-domain routing economics and dynamics, where policy can be expressed as contracting terms. In this paper, we present a Link-State Contract Routing (LSCR) protocol for long-term services and explore how inter-domain routing dynamics could be managed by adjusting "contract term" or routing service lifetime.

Several theoretical and experimental based models have been proposed to predict the fading envelope of the received signal in multipath condition. In this paper, we considered a model named Nakagami-m model. Nakagami-m can model a variety of fading environments, where it closely approximates the Nakagami-q (Hoyt) and the Nakagami-n (Rice) models, and has the Rayleigh and one sided Gaussian models as special cases. This model provides the best fit to land-mobile system like wireless mobile ad hoc Network (MANET). Under Nakagami-m fading model, received packet may not be clearly understood by the receiving node, which affects the routing protocol as well as the medium access control protocol of a network. The severity of Nakagami-m fading model on the network performance has been presented in this paper which is demonstrated via simulation results. Simulation results illustrate that the performance of a network may become unable to meet the expectation if Nakagami-m fading model is used in contrast to the simple two-ray model. A physical layer solution and a Medium Access Control (MAC) layer solution been proposed in this paper to overcome the effects of Nakagami-m fading model. Simulation results prove that these two solutions condense the Nakagami-m fading effect and improve network performance.