Pattern matching is a fundamental approach to detect malicious behaviors and information over Internet, which has been gradually used in high-speed network traffic analysis. However, there is a performance bottleneck ...Pattern matching is a fundamental approach to detect malicious behaviors and information over Internet, which has been gradually used in high-speed network traffic analysis. However, there is a performance bottleneck for multi-pattern matching on online compressed network traffic(CNT), this is because malicious and intrusion codes are often embedded into compressed network traffic. In this paper, we propose an online fast and multi-pattern matching algorithm on compressed network traffic(FMMCN). FMMCN employs two types of jumping, i.e. jumping during sliding window and a string jump scanning strategy to skip unnecessary compressed bytes. Moreover, FMMCN has the ability to efficiently process multiple large volume of networks such as HTTP traffic, vehicles traffic, and other Internet-based services. The experimental results show that FMMCN can ignore more than 89.5% of bytes, and its maximum speed reaches 176.470MB/s in a midrange switches device, which is faster than the current fastest algorithm ACCH by almost 73.15 MB/s.展开更多
二值图像编码在文本存储、图象检索中有广泛的应用。为了提高二值图像的压缩比,提出了一种利用OCR结果的JB IG 2(jo in t b i-leve l im age group)编码算法。它在对二值文本图像进行基于模式匹配的压缩时,利用了OCR识别结果和识别置信...二值图像编码在文本存储、图象检索中有广泛的应用。为了提高二值图像的压缩比,提出了一种利用OCR结果的JB IG 2(jo in t b i-leve l im age group)编码算法。它在对二值文本图像进行基于模式匹配的压缩时,利用了OCR识别结果和识别置信度的信息,从而更好地完成了字模重建和模式匹配的处理,提高了JB IG 2算法的性能。图像中所有识别结果可信的字符被重建字模代替,编码器只需编码字符的位置。实验结果表明:该算法优于以往JB IG 2算法的效果,它可以获得高于以往有损压缩算法的图像质量,并在实验图像上得到高于以往无损压缩算法14.3%的压缩比。展开更多
基金supported by China MOST project (No.2012BAH46B04)
文摘Pattern matching is a fundamental approach to detect malicious behaviors and information over Internet, which has been gradually used in high-speed network traffic analysis. However, there is a performance bottleneck for multi-pattern matching on online compressed network traffic(CNT), this is because malicious and intrusion codes are often embedded into compressed network traffic. In this paper, we propose an online fast and multi-pattern matching algorithm on compressed network traffic(FMMCN). FMMCN employs two types of jumping, i.e. jumping during sliding window and a string jump scanning strategy to skip unnecessary compressed bytes. Moreover, FMMCN has the ability to efficiently process multiple large volume of networks such as HTTP traffic, vehicles traffic, and other Internet-based services. The experimental results show that FMMCN can ignore more than 89.5% of bytes, and its maximum speed reaches 176.470MB/s in a midrange switches device, which is faster than the current fastest algorithm ACCH by almost 73.15 MB/s.
文摘二值图像编码在文本存储、图象检索中有广泛的应用。为了提高二值图像的压缩比,提出了一种利用OCR结果的JB IG 2(jo in t b i-leve l im age group)编码算法。它在对二值文本图像进行基于模式匹配的压缩时,利用了OCR识别结果和识别置信度的信息,从而更好地完成了字模重建和模式匹配的处理,提高了JB IG 2算法的性能。图像中所有识别结果可信的字符被重建字模代替,编码器只需编码字符的位置。实验结果表明:该算法优于以往JB IG 2算法的效果,它可以获得高于以往有损压缩算法的图像质量,并在实验图像上得到高于以往无损压缩算法14.3%的压缩比。