15949067
Security authentication of 3G-WLAN interworking
With the development of wireless Internet, the interworking of the third generation (3G) wide area wireless networks and wireless local area networks (WLAN) has become a focus of research. 3G systems have their advantages in charging management, roaming, and security facilities, and WLAN systems have the advantages of high bandwidth and low investment cost. Interworking of 3G-WLAN offers characteristics that complement each other perfectly. Several authentication protocols have been proposed to improve security. In this paper, we firstly introduce the architectures of 3G-WLAN interworking and discuss existing problems related to authentication and key agreement procedures. Then, we present two schemes by applying authentication based on EAP-TLS (extensible authentication protocol-transport layer security) and EAP-TTLS (tunneled TLS) into integrated 3G and WLAN to achieve high end-to-end security and authentication for the users. Finally, we conduct a series of performance evaluation on the energy consumption and latency of standard authentication protocols.
14723095
Optimal Priority Packetization with Multi-layer UEP for Video Streaming over Wireless Network
Most of current packetization schemes consider only bit error or packet erasure, both of which are common in wireless networks. This paper addresses these two problems together, and proposes an optimal packetization scheme for video streaming over wireless network, which is independent of video coding method. To combat the packet erasure, priority packetization combined with multi-layer unequal error protection (UEP) is applied on video frames. Multi-layer UEP contains low-complexity duplication of high-priority packet in application layer and different retransmission limit in media access control layer. Content-aware rate-distortion optimization is also introduced in order to countermine the distortion caused by bit errors. Simulations show that our scheme gains 2.17 dB or more compared with the conventional scheme.
15011396
Adaptive resource management for mobile multimedia communications in asymmetric wireless network
In the multi-service wireless networks, the bandwidth asymmetry is the distinctive characteristic. To avoid wasting uplink and downlink bandwidth in asymmetric network, admissible region for the nonreal-time (NRT) calls has been proposed. But in that scheme the static guard capacity for RT and NRT calls cannot adapt to traffic variation. In addition, the differentiated QoS services to users are not considered. In this paper, we propose an adaptive guard channel reservation (AGCR) scheme, which has the following novelties: i) the guard capacity for each class is dynamically adjusted so as to adapt to dynamic traffic, ii) the blocking probabilities of classes with higher priority are kept below certain targets and iii) differentiated QoS services to users are provided by maintaining the blocking probability ratios over different classes at the predefined targets. Simulation results have demonstrated the proposed AGCR scheme can keep the blocking probabilities of classes with higher priority below certain targets, track the ratios close to the targets well while maintaining a high bandwidth utilization
5812336
A Key Embedded Video Codec for Secure Video Multicast
The problem of controlling access to multimedia multicasts requires the distribution and maintenance of keying information. This paper proposes a new key embedded video codec for the media-dependent approach that involves the use of a data-dependent channel, and can be achieved for multimedia by using data embedding techniques. Using data embedding to convey keying information can provide an additional security and reduce the demand of bandwidth. In this paper, we develop a new statistical data embedding algorithm on compression-domain, then, by combining FEC (Forward Error Correction) algorithm and our proposed key information frame format. After a series of simulation experiments, we find that the new codec can satisfy the special demand of media-dependent approach. At the same time, the codec provides good performance.
28815316
Stability analysis of buffer priority scheduling policies using Petri nets
A Petri net approach to determining the conditions for stability of a re-entrant system with buffer priority scheduling policy is described in this paper. The concept of buffer boundedness based on the dynamic behavior of the marking in the system model is emphasized. The method is used to demonstrate the stability of the first buffer first served (FBFS) and the last buffer first served (LBFS) scheduling policies. finally a sufficient condition for instability of systems with a positive feedback loop (PFL) is established, and an example is given.
16307564
Architecture of Trustworthy Networks
Existing isolated and add-on secure systems are rarely robust under attack, misoperation and internal faults. Secure communication only offers little protection if one ore more components are compromised, and are not sufficient for holistic and systemic security. This paper proposes the concept of trustworthy networks, which makes advances along these traditional researches on network security in combination. We outline the key challenges in constructing trustworthy networks, and define three properties, namely security, survivability and controllability. Consulting human interactions, the abstract architecture for trustworthy networks is proposed, depicting protocols layers, topology structure, entities and components, and protocol steps
22088959
Analysis of Nonstationary Time Series Using Support Vector Machines
Time series from alternating dynamics have many important applications. In [5], the authors propose an approach to solve the drifting dynamics. Their method directly solves a non-convex optimization problem. In this paper, we propose a strategy which solves a sequence of convex optimization problems by using modified support vector regression. Experimental results showing its practical viability are presented and we also discuss the advantages and disadvantages of the proposed approach.
8448956
From Single to Multi-document Summarization
NeATS is a multi-document summarization system that attempts to extract relevant or interesting portions from a set of documents about some topic and present them in coherent order. NeATS is among the best performers in the large scale summarization evaluation DUC 2001.
47470200
Multipurpose virtual-reality-based motion simulator
Public security has become an important issue everywhere. In particular, the safe manipulation and control of various machines and vehicles has gained special attention such that the authorities keep emphasizing the strict training and censoring of human operators. Currently, such training and censoring processes usually rely on the actual machines, equipment, or vehicles in the real sites. This not only has high demands in space, time and cost, but also causes another phase of public security problem. In connection with this, the world-wide trend is to tackle the above dilemma by using virtual reality (VR). However, the current VR research or products are more mature in the software display part of VR. How to combine a 3D VR display with a motion platform to achieve the aforementioned training and censoring purposes is an important research issue. The paper focuses on this research issue, and the goal is to develop a multipurpose virtual-reality-based motion simulation system to meet the requirements of public security in training and censoring of human operators.
32785610
Customizing Software Libraries for Performance Portability
5604476
A robust image authentication method distinguishing JPEG compression from malicious manipulation
Image authentication verifies the originality of an image by detecting malicious manipulations. Its goal is different from that of image watermarking, which embeds into the image a signature surviving most manipulations. Most existing methods for image authentication treat all types of manipulation equally (i.e., as unacceptable). However, some practical applications demand techniques that can distinguish acceptable manipulations (e.g., compression) from malicious ones. In this paper, we present an effective technique for image authentication which can prevent malicious manipulations but allow JPEG lossy compression. The authentication signature is based on the invariance of the relationships between discrete cosine transform (DCT) coefficients at the same position in separate blocks of an image. These relationships are preserved when DCT coefficients are quantized in JPEG compression. Our proposed method can distinguish malicious manipulations from JPEG lossy compression regardless of the compression ratio or the number of compression iterations. We describe adaptive methods with probabilistic guarantee to handle distortions introduced by various acceptable manipulations such as integer rounding, image filtering, image enhancement, or scaling-recaling. We also present theoretical and experimental results to demonstrate the effectiveness of the technique.