IMDEA Networks Institute Digital Repository
Not a member yet
1915 research outputs found
Sort by
Adaptive Scheduling over a Wireless Channel under Constrained Jamming
Get PDFWe consider a wireless channel between a single pair of stations (sender and receiver) that is being “watched” and disrupted by a malicious, adversarial jammer. However, the jammer’s power is constrained by parameters and , that represent the rate at which the adversary can jam a packet, and the length of the largest bursts of jams, respectively. This, corresponds to the translation of the Adversarial Queueing Theory (AQT) constrains, to channel jamming.
The sender’s objective is to transmit as much useful data as possible, over the channel, despite the jams that are caused by the adversary. In this work, we focus on a simplified version of the problem, where given a transmission period , the adversary is constrained in jamming up to packets. We believe it to be a building block for solving the general problem of AQT-based jamming.
We therefore develop deterministic scheduling algorithms that decide the lengths of the packets to be sent, in order to maximize the total payload successfully transmitted over period T in the presence of up to f packet jams, useful payload.
We first consider the case where all packets must be of the same length and compute the optimal packet length. Then, we consider adaptive algorithms; ones that change the packet length based on the feedback on jammed packets, and analyze them with respect to the simplified model, showing their optimality. Finally, we discuss how our solutions could be used to solve the more general problem.TRUEpu
An OpenFlow Architecture for Energy Aware Traffic Engineering in Mobile Networks
Get PDFTo cope with the growing traffic demand, future mobile networks will be denser and integrate heterogeneous technologies. However, if not properly engineered, such networks may incur in huge energy wastage when there is little traffic, and may suffer from an unbearable management burden caused by the variety of technologies integrated. In this paper, we propose and implement a novel management architecture for mobile networks based on OpenFlow, which supports resource-on-demand provisioning in a centralised control plane, and hides the technology specifics to the controller through the use of abstractions. The feasibility of the approach is demonstrated by a real-life prototype based on commercial, off-the-shelf devices.pu
Improving the Energy Benefit for 802.3az using Dynamic Coalescing Techniques
Get PDFIn this work, we propose a dynamic coalescing algorithm for IEEE 802.3az standard, which dynamically adapts coalescing operations based on the current load and on the delay experienced in the link. Our results show that our algorithm almost doubles the energy efficiency of EEE with static coalescing while keeping packet delay boundedTRUEpu
Online Scheduling FIFO Policies with Admission and Push-Out
Get PDFWe consider the problem of managing a bounded size First-InFirst-Out (FIFO) queue buffer, where each incoming unit-sized packet requires several rounds of processing before it can be transmitted out. Our objective is to maximize the total number of successfully transmitted packets. We consider both push-out (when a policy is permitted to drop already admitted packets) and non-push-out cases. We provide worst-case guarantees for the throughput performance of our algorithms, proving both lower and upper bounds on their competitive ratio against the optimal algorithm, and conduct a comprehensive
simulation study that experimentally validates predicted theoretical behavior.pu
Caching in flat mobile networks: design and experimental analysis
Get PDFMobile network operators are aiming at strategies to accommodate the expected huge traffic growth with limited impact on the core network load. Enhancing the mobile architecture, along with deploying content delivery networks, represent promising areas where operators are putting their efforts to reduce costs while meeting the service guarantees.
In this article we present a novel mobile architecture for 5G networks which benefits from the joint design of distributed mobility management and mobile video content delivery networks.
We first discuss the architectural aspects of this combination and then present our validation and performance results from a real Linux-based prototype implementationTRUEpu
Distributed Mobility Management for a Flat Architecture in 5G Mobile Networks: Solutions, Analysis and Experimental Validation
Get PDFIn the last years, the commercial deployment of data services in mobile networks has been evolving quickly, providing enhanced radio access technologies and more efficient network architectures.
Nowadays, mobile users enjoy broadband and ubiquitous wireless access through their portable devices, like smartphones and tablets, exploiting the connectivity offered by the modern 4G network.
Nevertheless, the technological evolution keeps moving towards the development of next generation networks, or 5G, aiming at further improving the current system in order to cope with the huge data traffic growth foreseen in the future years.
One of the possible research guidelines aims at innovating the mobile networks architecture by designing a flat system.
Indeed, current systems are built upon a centralized and hierarchical structure, where multiple access networks are connected to a central core hosting crucial network functions, e.g., charging, control and maintenance, as well as mobility management, which is the main topic of this thesis.
In such a central mobility management system, users' traffic is aggregated at some key nodes in the core, called mobility anchors.
Thus, an anchor can easily handle user's mobility by redirecting traffic flows to his/her location, but i) it poses scalability issues, ii) it represents a single point of failure, and iii) the routing path is in general suboptimal.
These problems can be overcome moving to a flat architecture, adopting a Distributed Mobility Management (DMM) system, where the centralized anchor is removed.
This thesis develops within the DMM framework, presenting the design, analysis, implementation and experimental validation of several DMM protocols.
In this work we describe original protocols for client-based and network-based mobility management, as well as a hybrid solution.
We study analytically our solutions to evaluate their signalling cost, the packet delivery cost, and the latency introduced to handle a handover event.
Finally, we assess the validity of some of our protocols with experiments run over a network prototype built in our lab implementing such solutions.Telematics EngineeringUniversidad Carlos III de Madrid, Spainpu
Economics of Internet Interdomain Interconnections
Get PDFThe Internet is an evolving ecosystem where a multitude of interconnected networks, or Autonomous Systems (ASes), support global connectivity of end users. By providing economic incentives for routing traffic on behalf of other networks, interconnection agreements between ASes are a cornerstone of the Internet. However, rapid Internet adoption, unrelenting traffic growth, and increasing demands for quality and performance are challenging to cope with, provoke recurrent conflicts over the economic settlement of interconnections, and question the capacity of the Internet to provide critical services. Furthermore, with their capital-intensive network infrastructure, the ASes’ need to recover costs complicates interconnection negotiations and settlements. Overcoming the limitations and bottlenecks of the evolving Internet ecosystem, requires understanding the economics of how networks interconnect and how traffic is routed through them.
This thesis studies the economic aspects of the interconnections between ASes, identifies challenges hampering the future of the Internet, and proposes solutions to resolve them. We begin by presenting the first analytical and empirical study on remote peering, an emerging type of interconnections that relaxes the geographical constraints of ASes and also facilitates interconnections at a lower cost. Then we introduce Cooperative IP Transit (CIPT) and Transit for Peering (T4P), two novel interconnection arrangements that reduce traffic delivery costs for the ASes. However, some of the limitations are inherent to the current Internet architecture. To overcome those constraints, we present Route Bazaar, a new Internet architecture that, inspired by the use of the block chain mechanism and cryptographic tools in cryptocurrencies, provides a contractual framework for flexible interconnections with rich policies.Information and Knowledge Society Doctoral ProgrammeInternet Interdisciplinary Institute - Open University of Catalonia (IN3 - UOC), Barcelona, Spainpu
Routes and Interconnectivity: An Internet Trend and an Architectural Proposal
No full textThe Internet is a diverse ecosystem where a multitude of networks interconnect to provide end users with a global reach. Interconnection agreements supply economic incentives for networks to deliver traffic along end-to-end paths. Driven by the rapid Internet adoption, unrelenting traffic growth, and increasing demands for performance and quality, Internet interconnections evolve and affect traffic routing.
In this seminar, we first explore an emerging phenomenon of remote peering, an interconnection where remote networks peer via a layer-2 provider. While our measurements reveal significant presence of remote peering at IXPs (Internet eXchange Points) worldwide and a substantial potential to offload transit traffic, we also discuss implications of remote peering for Internet topology modeling. Then, we propose Route Bazaar, a new architecture for flexible Internet connectivity. Inspired by cryptocurrencies, the use of a block chain in Route Bazaar enables multilateral contracts for end-to-end routing with QoS (Quality of Service), rich private policies, and public accountability.TRUEpu
Proceedings of the 13th IEEE International Symposium on Parallel and Distributed Processing with Applications (IEEE ISPA-15)
No full textTRUEpu
Tackling the increased density of 5G networks; the CROWD approach
Get PDFThe significant growth in mobile data traffic and the ever-increasing user’s demand for high-speed, always connected networks continue challenging network providers and lead research towards solutions to enable faster, scalable and more flexible networks. In this paper we present the CROWD approach, a networking framework providing mechanisms to tackle the high densification and heterogeneity of wireless networks. The goal of CROWD is to design protocols and algorithms for very dense and heterogeneous wireless networks, which we call DenseNets. The mechanisms we propose include energy efficiency, MAC enhancements, connectivity management and backhaul configuration to contribute to the next generation of networks considering density as a resource instead of as an obstacle.TRUEpu