Abstract. Optical networking is the cornerstone of the Future Internet as it provides the physical infrastructure of the core backbone networks. Recent developments have enabled much better quality of service/experience for the end users, enabled through the much higher capacities that can be supported. Furthermore, optical networking developments facilitate the reduction of complexity of operations at the IP layer and therefore reduce the latency of the connections and the expenditures to deploy and operate the networks. New research directions in optical networking promise to further advance the capabilities of the Future Internet. In this book chapter, we highlight the latest activities of the optical networking community and in particular what has been the focus of EU funded research. The concepts of flexible and cognitive optical networks are introduced and their key expected benefits are highlighted. The overall framework envisioned for the future cognitive flexible optical networks are introduced and recent developments are presented.

Abstract-Deterministic propagation models are typically validated by performing comparisons between real and simulated E-field envelope distributions. These distributions correspond to straight spatial segments and, occasionally, also surfaces. This approach is correct to study large scale fading for relatively large distances. However, in a real environment and shorter distances, there are too many details to consider. As a result, it is almost impossible to reach a point by point match in a minimally realistic experiment. There are two ways to deal with this problem. The first one is to model every minor detail everywhere around us, keeping the point by point metric. The second one is to change that metric in order to admit, at least in part, that we can not take into account of all the details. If uncertainty can not be eliminated, we should learn to take advantage of it by using a statistical metric like the one proposed here. This paper uses such a kind of metric to validate several structural and geometrical simplifications of a model for the transition between outdoor and indoor propagation that has been recently published. Furthermore, we demonstrate that this metric has helped us to improve and understand better this model, while revealing unexpected model properties at the same time.

Abstract-We present a novel outdoor-indoor radio wave propagation model. It predicts the electric field envelope Cumulative Distribution Function (CDF) in a room placed near a radio communication emitter. The experimental CDF obtained from the simulation, fits the experimental CDF obtained from a measurement campaign carried out over 19200 sampling points inside the room. The maximum deviation found between these CDFs is less than 1%. Kolmogorov-Smirnov test is employed to analyze the goodness of fit. P-values around 99% are reached. A comparison is made with other classical methods reported in the literature as ray-tracing (RT) and a hybrid method employing finite-difference time-domain (FDTD) together with RT. The proposed model significantly improves the results achieved in those previous investigations. Although we study the problem in three dimensions, the repetitive nature of the algorithm allows us to parallelize the computation process speeding the calculations.

The integration of Software Defined Networking (SDN) technologies in Passive Optical Networks (PONs) would provide great advantages to Internet Service Providers (ISPs) and Network Operators, since they can optimize the network operation and reduce its complexity. However, some tasks regarding online service and network configuration strategies are difficult to move to external SDN-controllers since they are time-critical operations. However, the control of some of these policies by SDN techniques could lead to better network and management configuration in a centralized and automatic way. As a consequence, we propose and experimentally test the integration of an OpenFlow approach over legacy Gigabit Passive Optical Networks (GPONs), which allows moving some global service configuration policies to an external SDN controller implementing an SDN management layer that adjust these strategies according to dynamic Quality of Service (QoS) requirements of services in residential users. The viability and efficiency of our approach are demonstrated using a GPON testbed and proposing a new business scenario for ISPs and Network Operators.

Abstract-Inaccurate range estimates often restrict indoor positioning systems, resulting in a more remarkable drawback when using an already-deployed IEEE 802.11 network. This is the case of the time delay based location system that this paper deals with. The main causes of these inaccuracies are multipath and non-line-of-sight (NLOS) effects. These effects can be solved to a large degree by characterizing arrival times and range estimation errors. For this reason, this paper analyzes multipath and NLOS effects involved in the round-trip time (RTT) discrete measuring process, which is conducted before each range estimate. RTT observations obtained in this process for different real indoor environments provide useful statistical information that allows to make the work extendable to other similar scenarios. Moreover, from this statistical information, the nodes in the network can estimate several parameters of the range estimates distribution while performing the location process. These are used to reduce the error caused by multipath components and to predict and correct the NLOS biases produced. In this way, the NLOS error is dynamically estimated and corrected, achieving better results than classical approaches based on static parameters.