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In this paper, we describe the design considerations and implementation of a smart toy system, a technology for supporting the automatic recording and analysis for detecting developmental delays recognition when children play using the smart toy. To achieve this goal, we take advantage of the current commercial sensor features (reliability, low consumption, easy integration, etc.) to develop a series of sensor-based low-cost devices. Specifically, our prototype system consists of a tower of cubes augmented with wireless sensing capabilities and a mobile computing platform that collect the information sent from the cubes allowing the later analysis by childhood development professionals in order to verify a normal behaviour or to detect a potential disorder. This paper presents the requirements of the toy and discusses our choices in toy design, technology used, selected sensors, process to gather data from the sensors and generate information that will help in the decision-making and communication of the information to the collector system. In addition, we also describe the play activities the system supports.

The IETF P2PSIP WG is currently standardising a protocol for distributed multimedia services combining the media session functionality of SIP and the decentralised distribution and localisation of resources in peer-to-peer networks. The current P2PSIP scenarios only consider the infrastructure for the connectivity inside a single domain. This paper proposes an extension of the current work to a hierarchical multi-domain scenario: a two level hierarchical peer-to-peer overlay architecture for the interconnection of different P2PSIP domains. The purpose is the creation of a global decentralised multimedia services in enterprises, ISPs or community networks. We present a study of the Routing Performance and Routing State in the particular case of a two-level Distributed Hash Table Hierarchy that uses Kademlia. The study is supported by an analytical model and its validation by a peer-to-peer simulator.

Software defined networking (SDN) aims to provide simplified network design, operation, and management using a decoupled control plane. However, its centralized control and global network knowledge present scalability and reliability issues, which makes SDN deployment very challenging. In this paper, we propose and evaluate a hybrid switch with partial delegation of basic bridging and new cooperative mechanisms between controller and switches. This delegation offloads the SDN controllers while maintaining the capability to install forwarding rules on the switches. In this way, we take full advantage of hybrid switches in addition to using them as backwards compatible equipment, which interoperates with traditional switches.We validate this proposal by implementing a hybrid OpenFlow switch on an open source software switch as a proof of concept. Scalability and path setup delay are improved with respect to traditional centralized SDN solutions, because of the reduction in controller load and, in turn, because of the reduced traffic between switches and controller. Our cooperative mechanisms focus on recovering failures, obtaining the best performance of all approaches on higher loads, and providing a good trade‐off between controller based and traditional distributed approaches.

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This article gives an overview of the current practical approaches under study for a scalable implementation of multicast in layer 2 and 3 VPNs over an IP-MPLS multiservice network. These proposals are based on a well-known technique: the aggregation of traffic into shared trees to manage the forwarding state vs. bandwidth saving trade-off. This sort of traffic engineering mechanism requires methods to estimate the resources needed to set up a multicast shared tree for a set of VPNs. The methodology proposed in this article consists of studying the effect of aggregation obtained by random shared tree allocation on a reference model of a representative network scenario. site L2VPN. This is the context where P2MP LSPs may save bandwidth for the SP at the cost of a significant increase of forwarding state in core routers. As we shall review, experts have surrendered to the evidence that only an intelligent aggregation of multiple VPNs into the same multicast/broadcast tree can yield important bandwidth savings at a reasonable cost. How this partition and assignment of VPNs to trees should be made is an open research issue, given the diversity of topologies, traffic, and sites of different VPNs and backbone networks. On the other hand, high-rate flows may justify the setup of group-membership-aware multicast trees to avoid traffic in nodes not leading to group receivers. ADVANCES IN CONTROL AND MANAGEMENT OF CONNECTION-ORIENTED NETWORKSIsaiasThe rest of this article is organized as follows. We describe how to build P2MP trees in an MPLS network suitable for arbitrary aggregation of VPN trees. We present the problem of how to bundle and share multipoint LSPs in a scalable way and the techniques being developed in the Internet Engineering Task Force (IETF) for this purpose. We explore the trade-off of state vs. bandwidth in the particular multicast VPN context. We draw a few practical conclusions and suggest directions for future work. SIGNALING POINT-TO-MULTIPOINT MPLS LSPSA fundamental functionality required to take advantage of multicast in the network core is the ability to set up and use P2MP label-based forwarding entries. There are two protocols defined by the IETF to build LSPs in MPLS networks: Resource Reservation Protocol with Traffic Engineering (RSVP-TE) and Label Distribution Protocol (LDP). Both can be extended to support P2MP LSPs [2][3][4]. RSVP-TE builds the P2MP trees from the root to the leaves, whereas LDP builds the trees from the leaves to the root. In the case of IP multicast trees, LDP is intended to build the LSP following the IP multicast routing protocol. However, since all the solutions developed for scalable VPN multicast services are based on traffic engineered multi-VPN tree sharing, RSVP-TE is a more suitable tree setup protocol for this purpose. In fact, RSVP-TE indeed allows a tree to be constructed from a root router to a given set of leaf routers -in our case, the set of provider edge (PE) routers serving the sites of all the VPNs that have been selected to share the tree. ...

Software-Defined Networking (SDN) is a pillar of next-generation networks. Implementing SDN requires the establishment of a decoupled control communication, which might be installed either as an out-of-band or in-band network. While the benefits of in-band control networks seem apparent, no standard protocol exists and most of setups are based on ad-hoc solutions. This article defines Amaru, a protocol that provides plug&play resilient in-band control for SDN with low-complexity and high scalability. Amaru follows an exploration mechanism to find all possible paths between the controller and any node of the network, which drastically reduces convergence time and exchanged messages, while increasing robustness. Routing is based on masked MAC addresses, which also simplifies routing tables, minimizing the number of entries to one per path, independently of the network size. We evaluated Amaru with three different implementations and diverse types of networks and failures, and obtained excellent results, providing almost on-the-fly rerouting and low recovery time. INDEX TERMS SDN, OpenFlow, in-band control, resilient networks, path exploration.

Abstract. This paper addresses the topic of Fair QoE measurements in networking. The research of new solutions in networking is oriented to improve the user experience. Any application or service can be improved and the deployment of new solutions is mandatory to get the user satisfaction. However, different solutions exist; thus, it is necessary to select the most suitable ones. Nevertheless, this selection is difficult to make since the QoE is subjective and the comparison among different technologies is not trivial. The aim of this paper is to give an overview on how to perform fair QoE measurements to facilitate the study and research of new networking solutions and paradigms. However, previously to address this problem, an overview about how networking affects to the QoE is provided.