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Despite the widespread use of IP geolocation databases, a robust and precise method for evaluating their accuracy remains elusive. This study presents a novel algorithm designed to assess the reliability of IP geolocation databases, leveraging the congruence of delay distributions across network segments and cities. We developed a fusion reference database, termed CDCDB, to facilitate the evaluation of commercial IP geolocation databases. Remarkably, CDCDB achieves an average positioning accuracy at the city level of 94%, coupled with a city coverage of 99.99%. This allows for an effective and comprehensive evaluation of IP geolocation databases. When compared to IPUU, CDCDB demonstrates an increase in the number of network segments by 18.7%, an increase in the number of high-quality network segments by 13.2%, and an enhancement in the coverage of city-level network segments by 20.92%. The evaluation outcomes reveal that the reliability of IP geolocation databases is not uniform across different cities. Moreover, distinct IP geolocation databases display varying preferences for cities. Consequently, we advise online service providers to select suitable IP geolocation databases based on the cities they cater to, as this could significantly enhance service quality. [ABSTRACT FROM AUTHOR]

Palmprint biometrics has a broad application prospect owing to non-intrusiveness, ease of image acquisition and stable textural pattern. Hand-crafted approaches are vulnerable to non-ideal palmprint images caused by uneven illumination, motion blur and noise contamination. Many researchers have designed excellent texture descriptors or/and advanced image pre-processing algorithms. Nevertheless, they are highly targeted at some specific data, less adaptable to the emerging data. In this paper, a semi-pretrained contactless palmprint recognition deep network is developed to achieve high accuracy and robustness. Semi-CPRN is composed of underlying network structure from ResNet-152 and the proposed assistant layers dedicated to high-performance palmprint recognition. The well-designed assistant layers enhance convolutional neural network to steadily extract the real palmprint features even from the degraded images without being deceived by the degradation factors. Besides, to better carry out the research on palmprint recognition in the open environment, we established a new contactless database HIT-NIST-V1 under natural scene. The comparative experiments on CASIA, IITD, PolyU3D/2D, Tongji and HIT-NIST-V1 illustrate that Semi-CPRN is comparable and superior to previously published state-of-the-art approaches. Simultaneously, CNN-based palmprint biometrics methods show significant robustness to motion blur, Gaussian noise, and salt and pepper noise. [ABSTRACT FROM AUTHOR]

Millions of new domain names are registered every day, but a large proportion of them are malicious and usually discovered and blacklisted after the crime has been committed. In order to improve the security of domain name registration, this paper proposes a lightweight detection method based on the AdaBoost to identify malicious domain names, which focuses on proactively detecting malicious domain names by exploring the abnormal WHOIS records. The domain name registries and registrars can adopt the proposed method as the first layer of defense to identify malicious domains on the domain registration stage. Extensive experiments on a large-scale database demonstrate that the proposed approach achieves satisfactory results on various malicious domain names. [ABSTRACT FROM AUTHOR]

The root server is at the top of the domain name hierarchical structure. To improve root service performance, each root deploys anycast nodes worldwide. What is the actual service performance of these nodes after deployment? We analyze the service performance of the root anycast nodes deployed in China based on the active measurement data detected by the VPs of different ISPs in different geographical locations. From the analysis, we find that the resolution performance of the roots with anycast nodes deployed in China is higher than that of roots without deployment. However, users of different operators have significant differences in accessing the root servers, such as parsing time, hitting anycast nodes, and most anycast nodes only providing services for one operator, limiting the service scope and reducing the service performance. The analysis results can help the root management and introduction institutions master the actual service status of the root servers, which can be used to optimize the performance of the existing root anycast nodes and provide a basis for deploying new root anycast nodes in the next step. Finally, we find that 67 top-level domain names are hijacked on the resolution path based on the measured data. [ABSTRACT FROM AUTHOR]