Matrix Factorization Techniques for Recommender Systems

This document provides updates to IEEE Std 802.16's MIB for the MAC, PHY and asso- ciated management procedures in order to accommodate recent extensions to the standard.

IEEE Standard for Local and Metropolitan Area Networks Part 16: Air Interface for Fixed Broadband Wireless Access Systems Draft Amendment: Management Information Base Extensions

A systematic literature review of blockchain-based applications: Current status, classification and open issues

The sharp increase in the number of smartphones on the market, with the Android platform posed to becoming a market leader makes the need for malware analysis on this platform an urgent issue.In this paper we capitalize on earlier approaches for dynamic analysis of application behavior as a means for detecting malware in the Android platform. The detector is embedded in a overall framework for collection of traces from an unlimited number of real users based on crowdsourcing. Our framework has been demonstrated by analyzing the data collected in the central server using two types of data sets: those from artificial malware created for test purposes, and those from real malware found in the wild. The method is shown to be an effective means of isolating the malware and alerting the users of a downloaded malware. This shows the potential for avoiding the spreading of a detected malware to a larger community.

/pdf/crowdroid-behavior-based-malware-detection-system-for-x2tq6w9qk1.pdf

Crowdroid: behavior-based malware detection system for Android

我的台灣, 看見心靈的故鄉 =2009林磐聳藝術與設計展

A variety of different clock-controlled stream ciphers and attacks on them have been described in a number of papers However, few word-oriented algorithms with an irregular clocking mechanism have been proposed This paper proposes a new design of irregular clocking for word-oriented stream ciphers that is dynamic feedback control and show analysis results of its security and performance The stream cipher K2 v20 is a secure and high-performance stream cipher using the dynamic feedback control, which is applicable for several applications We believe that the dynamic feedback control mechanism is potentially effective against several different types of attacks, not only existing attacks but also novel attacks

K2 Stream Cipher

Network coding is a way of transmitting information where nodes in a network combine incoming packets into a single one to increase throughput in some scenarios, nodes wishing to get the original information can perform decoding when enough packets have been received. Given its efficiency, the exclusive or (XOR) operation is very popular for network coding. One security concern for networks using network coding is the so called “pollution attack”, where an adversary introduces packets that are not combinations of the original ones. In this paper, we present a construction to prevent pollution attacks in XOR network coding that is suitable for networks where nodes must perform fast verifications. Unlike existing constructions in the literature which are based on XOR-homomorphic authentication functions, our construction can be instantiated with existing cryptographic primitives that are not related to the XOR operation. The core insight of our proposal is a carefully selected set of authenticated packets that are used to authenticate the network coding stream. We show that our proposal is computationally efficient at the intermediate nodes and that can be computed efficiently at the nodes which are generating the content.

XOR network coding pollution prevention without homomorphic functions

Secure two-party comparison plays a crucial role in many privacy-preserving applications, such as privacy-preserving data mining and machine learning. In particular, the available comparison protocols with the appropriate input/output configuration have a significant impact on the performance of these applications. In this paper, we firstly describe a taxonomy of secure two-party comparison protocols which allows us to describe the different configurations used for these protocols in a systematic manner. This taxonomy leads to a total of 216 types of comparison protocols.We then describe conversions among these types. While these conversions are based on known techniques and have explicitly or implicitly been considered previously, we show that a combination of these conversion techniques can be used to convert a perhaps less-known two-party comparison protocol by Nergiz et al. (IEEE SocialCom 2010) into a very efficient protocol in a configuration where the two parties hold shares of the values being compared, and obtain a share of the comparison result. This setting is often used in multi-party computation protocols, and hence in many privacy-preserving applications as well. We furthermore implement the protocol and measure its performance. Our measurement suggests that the protocol outperforms the previously proposed protocols for this input/output configuration, when off-line pre-computation is not permitted.

A Taxonomy of Secure Two-Party Comparison Protocols and Efficient Constructions

In many application scenarios, such as cloud computing and network function virtualisation, entities from different domains or their interactions are short-lived. Yet, it is often necessary to ensure accountability of events recorded by such entities about their application-specific interactions. The distributed and multi-domain nature of this problem makes a decentralised architecture imperative, particularly in the context of key management and trust. This architecture also needs to address challenges in terms of cross-domain privacy and confidentiality of shared data. For concreteness and without loss of generality, we consider the use case of firewalls as virtual network functions (VNFs) across multiple domains where short-lived firewall VNF instances spin up and down, logging events (e.g., security incidents) during their life spans. Such event logs need to exist, for purposes of accountability, beyond the life-cycles of their generating entities. In this position paper, we present a dual blockchain framework that facilitates the verification of integrity as well as authenticity of events while supporting privacy and confidentiality of data shared across multiple domains.

A Framework for Blockchain-Based Verification of Integrity and Authenticity

Many group key management schemes that reduce the total communication cost and/or the computational cost imposed on client devices have been proposed. However, optimizations of the key-management structure have not been studied. This paper proposes ways to optimize the key-management structure in a hybrid group key management scheme. The proposed method is able to minimize both the total communication cost and the computational cost imposed on client devices. First, we propose a probabilistic client join/leave model in order to evaluate the communication and computational costs of group key management schemes. This model idealizes client actions generally and considers the existence of the peaks of the joining/leaving frequency. Thus, we can analyze not only the average case scenario but also the worst case scenario using this model. Then, we formalize the total computation cost and the computational cost imposed on client devices in group key management schemes under the model. We present both an average case analysis and a worst case analysis. Finally, we show the parameters that minimize the total communication cost and the computational cost imposed on clients under the model. Our results should be useful in designing a secure group communication system for large and dynamic groups.

/pdf/optimization-of-group-key-management-structure-with-a-client-1emgac60cc.pdf

Shinsaku Kiyomoto

Papers

K2 Stream Cipher

XOR network coding pollution prevention without homomorphic functions

A Taxonomy of Secure Two-Party Comparison Protocols and Efficient Constructions

A Framework for Blockchain-Based Verification of Integrity and Authenticity

Optimization of Group Key Management Structure with a Client Join-Leave Mechanism