Data Mining - Concepts and Techniques.

Data Mining Practical Machine Learning Tools and Techniques

Topology control in a sensor network balances load on sensor nodes and increases network scalability and lifetime. Clustering sensor nodes is an effective topology control approach. We propose a novel distributed clustering approach for long-lived ad hoc sensor networks. Our proposed approach does not make any assumptions about the presence of infrastructure or about node capabilities, other than the availability of multiple power levels in sensor nodes. We present a protocol, HEED (Hybrid Energy-Efficient Distributed clustering), that periodically selects cluster heads according to a hybrid of the node residual energy and a secondary parameter, such as node proximity to its neighbors or node degree. HEED terminates in O(1) iterations, incurs low message overhead, and achieves fairly uniform cluster head distribution across the network. We prove that, with appropriate bounds on node density and intracluster and intercluster transmission ranges, HEED can asymptotically almost surely guarantee connectivity of clustered networks. Simulation results demonstrate that our proposed approach is effective in prolonging the network lifetime and supporting scalable data aggregation.

/pdf/heed-a-hybrid-energy-efficient-distributed-clustering-4c3cjgsfv9.pdf

HEED: a hybrid, energy-efficient, distributed clustering approach for ad hoc sensor networks

http://cpham.perso.univ-pau.fr/ENSEIGNEMENT/PAU-UPPA/RESA-M2/Clustering-abasi.pdf

A survey on clustering algorithms for wireless sensor networks

Topology Control (TC) is one of the most important techniques used in wireless ad hoc and sensor networks to reduce energy consumption (which is essential to extend the network operational time) and radio interference (with a positive effect on the network traffic carrying capacity). The goal of this technique is to control the topology of the graph representing the communication links between network nodes with the purpose of maintaining some global graph property (e.g., connectivity), while reducing energy consumption and/or interference that are strictly related to the nodes' transmitting range. In this article, we state several problems related to topology control in wireless ad hoc and sensor networks, and we survey state-of-the-art solutions which have been proposed to tackle them. We also outline several directions for further research which we hope will motivate researchers to undertake additional studies in this field.

/pdf/topology-control-in-wireless-ad-hoc-and-sensor-networks-3e17u396zt.pdf

Topology Control in Wireless Ad Hoc and Sensor Networks

Internet Service Providers (ISPs) use routing policies to implement the requirements of business contracts, manage traffic, address security concerns and increase scalability of their network. These routing policies are often a high-level expression of strategies or intentions of the ISP. They have meaning when viewed from a network-wide perspective (e.g., mark on ingress, filter on egress). However, configuring these policies for the Border Gateway Protocol (BGP) is undertaken at a low-level, on a per router basis. Unintended routing outcomes have been observed. In this work, we define a language that allows analysis of network-wide configurations at the high-level. This language aims at bridging the gap between router configurations and abstract mathematical models capable of capturing complex policies. The language can be used to verify desired properties of routing protocols and hence detect potential unintended states of BGP. The language is accompanied by a tool suite that parses router configuration languages (which by their nature are vendor-dependent) and translates them into vendor-independent representations of policies.

/pdf/detecting-the-unintended-in-bgp-policies-gpjqjwimhq.pdf

Detecting the unintended in BGP policies

The essential process to analyze signals from multicarrier communication systems is to isolate independent communication channels using a channelizer. To implement a channelizer in software-defined radio systems, the Polyphase Filterbank (PFB) is commonly used. For real-time applications, the PFB has to process the digitized signal faster or equal to its sampling rate. Depending on the underlying hardware, PFB can run on a CPU, a Graphical Processing Unit (GPU), or even a Field-Programmable Gate Arrays (FPGA). CPUs and GPUs are more reconfigurable and scalable platforms than FPGAs. In this paper, we optimize an existing implementation of a CPU-based channelizer and implement a novel GPU-based channelizer. Our proposed solutions deliver an overall improvement of 30 % for the CPU optimization on Intel Core i7-4790 @ 3.60 GHz, and a 3.2-fold improvement for the GPU implementation on AMD R9 290, when compared to the original CPU-based implementation.

Wired/Wireless Internet Communications

This paper proposes an algorithm for aggregating virtual channel connections (VCCs) onto virtual path connections (VPSs) in asynchronous transfer mode (ATM) networks. We focus on the interesting problem of multiplexing onto an available bit rate (ABR) VPC. ABR VPCs are particularly useful for connecting enterprise sites over the Internet, providing a virtual private network (VPN). The VPC/VCC hierarchy is also important for supporting Internet differentiated services over ATM. The coupling between the flow control mechanisms for VCCs and VPCs is not standardized. We propose fairness definitions for VPC bandwidth allocation, and describe an algorithm for allocating the VPC capacity to the multiplexed VCCs. Preliminary simulation results indicate that the algorithm achieves the required fair allocations, while controlling queue sizes.

/pdf/a-framework-for-virtual-channel-onto-virtual-path-2cm8x6u9xr.pdf

A framework for virtual channel onto virtual path multiplexing in ATM-ABR

Networked embedded systems provide a versatile computing platform for supporting applications, such as environmental monitoring or military field surveillance. These networks are typically deployed in harsh environments and left unattended, which makes it impossible to re-charge their node batteries. Motivated by the large scale of sensor deployment, the high cost of wireless communications, the limited capabilities of sensor nodes, and the hostility of the encompassing environment, we design distributed protocols for topology management and network synchronization. We investigate problems that are specific to heavily-loaded sensor networks serving applications that can exploit data aggregation. We address applications that are either source-driven (in which sensors periodically send their reports to an observer), or query-driven (in which a subset of sensors respond to an observer's query). 
We construct a hierarchical (clustered) network in which a subset of nodes are elected as super-nodes (or cluster heads). These heads constitute the routing infrastructure and aggregate data from their neighboring non-head nodes. The super-node functionality is rotated among network nodes to achieve load balancing and prolong the lifetime of every individual sensor. For sensors deployed in harsh environments, we propose a methodology for improving the connectivity of the hierarchical network and providing opportunities for multi-path routing. In addition, we consider applications and protocols that require node synchronization, and design a framework for time synchronization in multi-hop hierarchical networks that is based on relative synchronization.

An energy-efficient architecture for wireless sensor networks

Abstracr-This paper designs a detection system to measure QoS in differentiated services networks. The system detects a number of bandwidth theft and denial of service attacks. We use a distl"ibuted monitoring approach, \\lith measurement agents collecting information about the traffic characteristics at aU the nodes of a DS domain, and reporting to a central management station that performs analysis to detect possible SLA violations, bandwidth theft or denial attacks. We are implementing and testing the system on a differentiated services testbed to evaluate if we can effectively detect such attacks. OUI' system can be useful in developing mechanisms for response and damage control in QoS enabled networks.

/pdf/on-detecting-bandwidth-theft-attacks-and-sla-violations-in-1t33tt8aw7.pdf

Sonia Fahmy

Papers

Detecting the unintended in BGP policies

Wired/Wireless Internet Communications

A framework for virtual channel onto virtual path multiplexing in ATM-ABR

An energy-efficient architecture for wireless sensor networks

On Detecting Bandwidth Theft Attacks and SLA Violations in QoS Networks