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[EN] Although intelligent agent-based systems have existed for several years, the progression in terms of real applications or their integration in the industry have not yet reached the expected levels. During the last two decades, many agent platforms have appeared with the aim of simplifying the development of multi-agent systems. Some of these platforms have been designed for general purposes, while others have been oriented towards specific domains. However, the lack of standards and the complexity associated with supporting such systems, among other difficulties, have hampered their generalised use. This article looks in depth at the current situation of existing agent platforms, trying to analyse their current shortcomings and their expected needs in the near future. The goal of the paper is to identify possible lines of work and some of the most crucial aspects to be considered in order to popularize the application of agent technology as a dynamic and flexible solution to current problems. Moreover, the paper presents SPADE 3, a new version of the SPADE middleware, which has been totally redesigned in order to conform to the identified challenges. Finally, a case study is proposed to illustrate how SPADE 3 is able to fulfill these challenges.

© 2019 IEEE. Personal use of this material is permitted. Permissíon from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertisíng or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works., [EN] Virtualization techniques have been shown to report benefits to data centers and other computing facilities. In this regard, not only virtual machines allow to reduce the size of the computing infrastructure while increasing overall resource utilization, but also virtualizing individual components of computers may provide significant benefits. This is the case, for instance, for the remote GPU virtualization technique, implemented in several frameworks during the recent years. The large degree of flexibility provided by the remote GPU virtualization technique can be further increased by applying the migration mechanism to it, so that the GPU part of applications can be live-migrated to another GPU elsewhere in the cluster during execution time in a transparent way. In this paper we present the implementation of the migration mechanism within the rCUDA remote GPU virtualization middleware. Furthermore, we present a thorough performance analysis of the implementation of the migration mechanism within rCUDA. To that end, we leverage both synthetic and real production applications as well as three different generations of NVIDIA GPUs. Additionally, two different versions of the InfiniBand interconnect are used in this study. Several use cases are provided in order to show the extraordinary benefits that the GPU-job migration mechanism can report to data centers.

The objective of this paper is to explain novel sustainable robotics solutions for cities. Those new proposals appear under the ECHORD++ project which is a good tool to meet academia and industry with the objective of providing innovative technological solutions. In this paper, authors explain the tool as well as the methodology to promote robotics research in urban environments, and the on-going experience will demonstrate that huge advances are made in this field.

[Abstract] Current Graphics Processing Units (GPUs) are capable of obtaining high computational performance in scientific applications. Nevertheless, programmers have to use suitable parallel algorithms for these architectures and usually have to consider optimization techniques in the implementation in order to achieve said performance. There are many efficient proposals for limited-size problems which fit directly in the shared memory of CUDA GPUs, however, there are few GPU proposals that tackle the design of efficient algorithms for large problem sizes that exceed shared memory storage capacity. In this work, we present a tuning strategy that addresses this problem for some parallel prefix algorithms that can be represented according to a set of common permutations of the digits of each of its element indices [1], denoted as Index-Digit (ID) algorithms. Specifically, our strategy has been applied to develop flexible Multi-Stage (MS) algorithms for the Fast Fourier Transform (FFT) algorithm (MS-ID-FFT) and a tridiagonal system solver (MS-ID-TS) on the GPU. The resulting implementation is compact and outperforms other well-known and commonly used state-of-the-art libraries, with an improvement of up to 1.47x with respect to NVIDIA's complex CUFFT, and up to 33.2x in comparison with NVIDIA's CUSPARSE for real data tridiagonal systems.

The emerging high-efficiency video coding standard achieves higher coding efficiency than previous standards by virtue of a set of new coding tools such as the quadtree coding structure. In this novel structure, the pixels are organized into coding units (CU), prediction units, and transform units, the sizes of which can be optimized at every level following a tree configuration. These tools allow highly flexible data representation; however, they incur a very high computational complexity. In this paper, we propose an effective complexity control (CC) algorithm based on a hierarchical approach. An early termination condition is defined at every CU size to determine whether subsequent CU sizes should be explored. The actual encoding times are also considered to satisfy the target complexity in real time. Moreover, all parameters of the algorithm are estimated on the fly to adapt its behavior to the video content, the encoding configuration, and the target complexity over time. The experimental results prove that our proposal is able to achieve a target complexity reduction of up to 60% with respect to full exploration, with notable accuracy and limited losses in coding performance. It was compared with a state-of-the-art CC method and shown to achieve a significantly better trade-off between coding complexity and efficiency as well as higher accuracy in reaching the target complexity. Furthermore, a comparison with a state-of-the-art complexity reduction method highlights the advantages of our CC framework. Finally, we show that the proposed method performs well when the target complexity varies over time.

The motivation behind the Locator/Identifier Separation Protocol (LISP) has shifted over time from routing scalability issues in the core Internet to a set of use cases for which LISP stands as a technology enabler. Among these are the mobility of physical and virtual appliances without breaking their TCP connections, seamless migration and fast deployments of IPv6, multihoming, and data-center applications. However, LISP was born without security, and therefore is susceptible to attacks in its control-plane. The IETF's LISP working group has recently started to work in this direction, but the protocol still lacks end-to-end mechanisms for securing the overall registration process on the mapping system. In this paper, we address this issue and propose a solution that counters the attacks. We have deployed LISP in a real testbed, and compared the performance of our proposal with current LISP implementations, in terms of both messaging and packet size overhead. Our preliminary results prove that our solution offers much higher security with minimum overhead.