Theophilus Wellem

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Sketch-based algorithms are widely used in networking applications due to its many good attributes. We propose to use Graphics Processing Unit (GPU) as an accelerating engine to offload heavy sketch computations for network traffic change detection. Our experiment results show that GPU can conduct fast change detection with query operation up to 9 million(More)
Sketch-based algorithms are widely applied in various networking applications. In this paper, we present a compact implementation for on-line traffic change detection on a NetFPGA platform. The system utilizes a straight forward scheme to reveal the key of flow with tradeoff on the accuracy for hardware simplicity. It is capable of digesting traffic up to(More)
Monitoring the temperature of a computer server room is a critical task to ensure the performance of the server is not disturbed by excessive room temperature. In this paper, we designed and implemented a microcontroller-based room temperature monitoring system using Atmel ATmega8535 microcontroller and National Semiconductor's LM35 temperature sensor.(More)
Sketch-based data streaming algorithms are used in many network monitoring applications. The sketch data structure is capable of summarizing high-speed network traffic in real-time and producing accurate estimation result of a specific traffic measurement task. However, due to the fixed hardware implementation of the sketch counter array, the flexibility of(More)
We propose a system to detect superspreaders based on combinations of FM sketch, Bloom filter and hash table. It first eliminates sources which are not potential superspreaders, then counts the number of connections to distinct destinations (fan-out) for remaining sources. The proposed system is implemented on NetFPGA platform. Our experiment results show(More)
GPU and other SIMD stream architecture have been used for accelerating packet processing applications. This paper explores the design space on GPU for sketch-based network traffic change detection application by using OpenCL parallel programming framework. Due to the parallel nature of sketch data structure, the computations can be mapped to OpenCL(More)
Approximate string matching has been used in many applications such as, text retrieval, spell checker and DNA sequence matching in computational biology. In this paper, we implemented bit-vector algorithm using MATLAB for approximate string matching on Rhodopsin protein sequence of class Aves. Our experiments on real data of Rhodopsin protein sequences(More)
Heavy hitter detection is an important task in many network security and traffic measurement applications. In this work, we implement a heavy hitter detection accelerator based on the Count-Min sketch algorithm inside the NetFPGA-10G OpenFlow switch. By using only a small amount of extra memory and logic resources, the OpenFlow switch is capable of(More)
Sketch-based methods are widely used in highspeed network monitoring applications. In this paper, we present a parallel implementation of sketch computations using Open Computing Language (OpenCL) on Graphics Processing Unit (GPU) for network traffic change detection. The parallel nature of the computation on sketch data structure makes it suitable for(More)