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We construct binary codes for fingerprinting digital documents. Our codes for n users that are -secure against c pirates have length O(c² log(n/ϵ)). This improves the codes proposed by Boneh and Shaw [1998] whose length is approximately the square of this length. The improvement carries over to works using the Boneh-Shaw code as a primitive, for example, to the dynamic traitor tracing scheme of Tassa [2005]. By proving matching lower bounds we establish that the length of our codes is best within a constant factor for reasonable error probabilities. This lower bound generalizes the bound found independently by Peikert et al. [2003] that applies to a limited class of codes. Our results also imply that randomized fingerprint codes over a binary alphabet are as powerful as over an arbitrary alphabet and the equal strength of two distinct models for fingerprinting. [ABSTRACT FROM AUTHOR]

Search, retrieval and storage of video content over the Internet and online repositories can be efficiently improved using compact summarizations of this content. Robust and perceptual fingerprinting codes, extracted from local video features, are astutely used for identification and authentication purposes. Unlike existing fingerprinting schemes, this paper proposes a robust and perceptual fingerprinting solution that serves both video content identification and authentication. While content identification is served by the robustness of the proposed fingerprinting codes to content alterations and geometric attacks, their sensitivity to malicious attacks makes them fit for forgery detection and authentication. This dual usage is facilitated by a new concept of sequence normalization based on the circular shift properties of the discrete cosine and sine transforms (DCT and DST). Sequences of local features are normalized by estimating the circular shift required to align each of these sequences to a reference sequence. The fingerprinting codes, consisting of normalizing shifts, are properly modeled using information-theoretic concepts. Security, robustness and sensitivity analysis of the proposed scheme is provided in terms of the security of the secret keys used during the proposed normalization stage. The computational efficiency of the proposed scheme makes it appropriate for large scale and online deployment. Finally, the robustness (identification-based) and sensitivity (authentication-based) of the proposed fingerprinting codes to content alterations and geometric attacks is evaluated over a large set of video sequences where they outperform existing DCT-based codes in terms of robustness, discriminability and sensitivity to moderate and large size intentional alterations. [ABSTRACT FROM AUTHOR]

The Session Initiation Protocol (SIP) is commonly used to establish Voice over IP (VoIP) calls. However, the original authentication scheme for SIP-based service typically uses HTTP Digest authentication protocol, which is s not providing security at an acceptable level. In this paper, we propose a secure and practical password-only authenticated key agreement scheme for SIP using elliptic curve cryptography(ECC). Our scheme is remarkable efficient and quite simple to use. And yet we can provide the rigorous proof of the security for it. Therefore, the end result is more suited to be a candidate for SIP authentication scheme. In addition, we also suggest an extended scheme capable of providing anonymity, privacy, and location privacy to protect the user's personal information and his real identity. [ABSTRACT FROM AUTHOR]

In recent years, the security of encryption and signature schemes in the presence of key-dependent plaintexts received attention, and progress in understanding such scenarios has been made. In this article we motivate and discuss a setting where an adversary can access tags of a message authentication code (MAC) on key-dependent message inputs, and we propose a way to formalize the security of MACs in the presence of key-dependent messages ( KD−EUF). Like signature schemes, MACs have a verification algorithm, and hence the tagging algorithm must be stateful. We present a scheme MAC-ver which offers KD−EUF security and also yields a forward-secure scheme. [ABSTRACT FROM AUTHOR]

Vehicular Ad-hoc Networks (VANETs) are wireless communication systems that provide safer and more efficient road services. Their interesting applications attract many researchers from both academia and industry. However, their security requirements represent challenges that should be addressed before VANETs can be deployed. Although there are several surveys covering VANETs, they either do not concentrate on security issues or do not cover recent work. In this paper, we provide a complete survey on recent security-related issues in VANETs. We present VANETs' security problems and the current techniques for solving them. We discuss to what extent each technique achieves security requirements such as authentication, integrity, privacy, and revocation of misbehaving vehicles. Finally, we present security problems in VANETs that are still open for future research. [ABSTRACT FROM AUTHOR]

Restricted strong partially balanced t-designs were first formulated by Pei, Li, Wang and Safavi-Naini in investigation of authentication codes with arbitration. In this article, we will prove that splitting authentication codes that are multi-fold perfect against spoofing can be characterized in terms of restricted strong partially balanced t-designs. We will also investigate the existence of restricted strong partially balanced 3-designs RSPBD 3-( v, b, 3 × 2; λ, λ, 1, 0) s, and show that there exists an RSPBD 3-( v, b, 3 × 2; λ, λ, 1, 0) for any $${v\equiv 9\ (\mbox{{\rm mod}}\ 16)}$$ . As its application, we obtain a new infinite class of 3-fold perfect splitting authentication codes. [ABSTRACT FROM AUTHOR]

In 2010 the Interlibrary Loan department of the University of South Florida Tampa moved to unify its ILLiad sign-on practices and align with the University-wide objective toward a single sign-on environment. Initial plans to implement authentication with CAS evolved in response to obstacles and system failures and resulted in an ILLiad, Shibboleth, and CAS combination. This article reviews the migration project and its culmination in a successful, and unique, authentication assembly. [ABSTRACT FROM AUTHOR]

In recent years, wireless sensor networks (WSNs) have been considered as a potential solution for real-time monitoring applications and these WSNs have potential practical impact on next generation technology too. However, WSNs could become a threat if suitable security is not considered before the deployment and if there are any loopholes in their security, which might open the door for an attacker and hence, endanger the application. User authentication is one of the most important security services to protect WSN data access from unauthorized users; it should provide both mutual authentication and session key establishment services. This paper proposes a robust user authentication framework for wireless sensor networks, based on a two-factor (password and smart card) concept. This scheme facilitates many services to the users such as user anonymity, mutual authentication, secure session key establishment and it allows users to choose/update their password regularly, whenever needed. Furthermore, we have provided the formal verification using Rubin logic and compare RUASN with many existing schemes. As a result, we found that the proposed scheme possesses many advantages against popular attacks, and achieves better efficiency at low computation cost. [ABSTRACT FROM AUTHOR]

Abstract: As a unique and reliable biometric characteristic, palmprint verification has achieved a great success. However, palmprint alone may not be able to meet the increasing demand of highly accurate and robust biometric systems. Recently, palmvein, which refers to the palm feature under near-infrared spectrum, has been attracting much research interest. Since palmprint and palmvein can be captured simultaneously by using specially designed devices, the joint use of palmprint and palmvein features can effectively increase the accuracy, robustness and anti-spoof capability of palm based biometric techniques. This paper presents an online personal verification system by fusing palmprint and palmvein inforA fast palmprint and palmvein recognition systemA fast palmprint and palmvein recognition system quality can vary much, a dynamic fusion scheme which is adaptive to image quality is developed. To increase the anti-spoof capability of the system, a liveness detection method based on the image property is proposed. A comprehensive database of palmprint–palmvein images was established to verify the proposed system, and the experimental results demonstrated that since palmprint and palmvein contain complementary information, much higher accuracy could be achieved by fusing them than using only one of them. In addition, the whole verification procedure can be completed in 1.2s, which implies that the system can work in real time. [ABSTRACT FROM AUTHOR]

Abstract: Authentication is the process of determining whether someone or something is, in fact, who or what it is declared to be. As the dependence upon computers and computer networks grows, the need for authentication has increased. Biometrics is the science and technology of authentication by identifying the living individual''s physiological or behavioral attributes. Keystroke dynamics is a behavioral measurement and it utilizes the manner and rhythm in which each individual types. The approaches in keystroke dynamics can be categorized by the selection of features and the classification methods employed. The objective of this review paper is to summarize the well-known approaches used in keystroke dynamics in the last two decades. [Copyright &y& Elsevier]

Abstract: Mutual entity authentication plays an important role in securing wireless sensor networks. In this paper, we propose a computationally efficient authentication framework, based on a well-studied problem—learning parity with noise (LPN). This kind of LPN-based authentication approaches only involve simplest bit-operations, which makes them suitable for resource-restrained sensor nodes. The proposed HB-hybrid framework introduces a new noise mode to prevent a general man-in-the-middle attack against previous LPN-based protocols, presents a gentle approach to securely combine several HB-like one-way authentication protocols and extends to mutual authentication which effectively thwarts the reflection attack. It spawns three specific protocols with different trade-offs between communication overload and memory cost. We extensively analyze their performance and security properties. Moreover, some optimization mechanisms on communication costs are given and the application scenarios for different wireless sensor networks are discussed at length. [ABSTRACT FROM AUTHOR]

This paper presents the hardware-software co-design of an elliptic curve cryptographic (ECC) system-on-chip (SoC) implementation of a mutual authentication protocol for network/data communication systems. Designing such computationally intensive cryptosystems, particularly for resource-constrained embedded applications using the conventional register transfer level (RTL) methodology leads to extended design cycles, inefficient design-space exploration, very long simulation cycles, tedious verification procedure, and sub-optimal final realization. The solution to this problem is to apply hardware-software co-simulation methods abstracted at the Electronic System Level (ESL). In the ESL modelling framework proposed in this paper, the Unified Modelling Language (UML) is used to create the design documents that describe the system static architecture and functional behaviour. SystemC is used in generating the cycle-accurate executable simulation models. A technique for design space exploration at the system level is also proposed to obtain the best hardware-software partitioning of the ECC SoC well before the final prototype is available. Experimental works with the proposed ESL co-design platform show that early system verification can be performed efficiently, and simulation speed of an ESL model is shown to be about 1000 times faster than the simulation of the equivalent RTL model. System execution time is estimated to be within 95% accuracy of its equivalent RTL. [ABSTRACT FROM AUTHOR]

Abstract: This paper deals with a novel vehicle manufacturer and model recognition scheme, which is enhanced by color recognition for more robust results. A probabilistic neural network is assessed as a classifier and it is demonstrated that relatively simple image processing measurements can be used to obtain high performance vehicle authentication. The proposed system is assisted by a previously developed license plate recognition, a symmetry axis detector and an image phase congruency calculation modules. The reported results indicate a high recognition rate and a fast processing time, making the system suitable for real-time applications. [ABSTRACT FROM AUTHOR]

The author reflects on the issues of retraction and corrections published in the journal "Anaesthesia." He stresses on the subject of ethics in research and its correlation to publication ethics which follow guidelines provided by the Committee on Publication Ethics (COPE) in Great Britain so that publication errors could be avoided. The author suggests the use of the iThenticate software CrossCheck scan to determine the authentication and authorship of editorials before publishing.

A practical web/python implementation of Zero-Knowledge Authentication protocol without any prior knowledge of the concept of Zero-Knowledge Proof. The Zero-Knowledge Proof is a concept used in many cryptography systems. It allows a party to prove that he/she knows something (i.e. credential), without having to send over the value of the credential. In this implementation, it will be used to prove the password of the user without sending over the actual password. The system also allows for no password hashes to be stored on the server. The purpose of the implementation is to make implementing the Zero-Knowledge Proof Authentication portable and easily customizable. This is achieved by using python based scripts in web applications to simulate the protocol. [ABSTRACT FROM AUTHOR]

The combination of wired and wireless technologies is spreading rapidly with the advance of Internet and networks, since it enables the creation of new services, and provides new features to both users and service providers. In such wired and wireless integrated services, network integration is very important, because such systems involve linking heterogeneous networks; and they involve integrating transmission technologies across networks. In this situation, existing security and communication technologies are unsuitable, since network integration involves heterogeneous networks. The network may have several security vulnerabilities. Also, the available services are for roaming users. In these services, we must provide fast authentication and security for roaming. Therefore, in this paper we proposed authentication and ID-based key management in pervasive environments. Our system provides efficient, secure communication. [ABSTRACT FROM AUTHOR]

Hopper and Blum (Asiacrypt 2001) and Juels and Weis (Crypto 2005) recently proposed two shared-key authentication protocols—HB and HB+, respectively—whose extremely low computational cost makes them attractive for low-cost devices such as radio-frequency identification (RFID) tags. The security of these protocols is based on the conjectured hardness of the “learning parity with noise” (LPN) problem, which is equivalent to the problem of decoding random binary linear codes. The HB protocol is proven secure against a passive (eavesdropping) adversary, while the HB+ protocol is proven secure against active attacks. [ABSTRACT FROM AUTHOR]

Abstract: The current study outlines the behavior of non-linear and non-group cellular automata having periodic boundary conditions. We find a CA having enough unique states which is called a length, and extract particular states from the CA based on some properties, i.e., Hamming distance, frequency, and run-up and run-down. The extracted states can be alternatively used for cryptographic applications which demand integrity and authentication of identities such as a one-time password scheme. [Copyright &y& Elsevier]

Biometric authentication presents an increasing interest in the last years. Among the usual biometric features employed in the authentication systems speech plays an important role and is well accepted by the users. Speech as biometric verifier has some important advantages in use, respectively: the low price for the sensors (microphone), the easy way (noninvasive) of samples acquisition, the large amount of available data for training and testing and the ability to provide real time processing. Our approach employs only features extracted in the time domain, so two orders smaller computational requirements are implied than in the case of usual frequency domain processing. Due to this quality a low complexity and low cost implementation may be done using an ATMEL microcontroller platform. The system is based on the TESPAR coding method for the feature extraction from speech signal allowing a real time processing on a medium power computation platform. The system performances proves the discrimination capability of the TESPAR method even when using only the distances for the classification task and encourages the improvement of the system for low cost applications. The method employment may be extended to other applications like biomedical waveform diagnostics (EEG, ECG) or industrial system monitoring. [ABSTRACT FROM AUTHOR]

The article discusses the security mechanism on Physical unclonable functions (PUF) in limiting the amount of leaked information. It presents the index-based syndrome coding (IBS), an error correction technique to explain its differences from coding method wherein IBS leaks less information and yields a higher coding gain. It also features the two-stage coding which is deemed to minimize error correction complexity by repetition coding and conventional syndrome generation using XOR masking. INSET: Related Work.

With the increasing use of computers nowadays, information security is becoming an important issue for private companies and government organizations. Various security technologies have been developed, such as authentication, authorization, and auditing. However, once a user logs on, it is assumed that the system would be controlled by the same person. To address this flaw, we developed a demonstration system that uses facial recognition technology to periodically verify the identity of the user. If the authenticated user's face disappears, the system automatically performs a log-off or screen-lock operation. This paper presents our further efforts in developing image preprocessing algorithms and dealing with angled facial images. The objective is to improve the accuracy of facial recognition under uncontrolled conditions. To compare the results with others, the frontal pose subset of the Face Recognition Technology (FERET) database was used for the test. The experiments showed that the proposed algorithms provided promising results. [ABSTRACT FROM AUTHOR]

Abstract: Radio frequency identification (RFID) technology has recently aroused great interest due to its convenience and economic efficiency. Through RFID become popular worldwide, it is susceptible to various attacks and security problems. Since RFID systems use wireless transmission, user privacy may be compromised by malicious people intercepting the information contained in the RFID tags. Many of the methods previously proposed to prevent such attacks do not adequately protect privacy or reduce database loading. In this paper, we propose a new authentication and encryption method that conforms to the EPC Class 1 Generation 2 standards to ensure RFID security between tags and readers. Our scheme not only reduces database loading, but also ensures user privacy. Finally, we survey our scheme from several security viewpoints, and prove its feasibility for use in several applications. [Copyright &y& Elsevier]

This paper shows that the advantage of any q-query adversary (which makes at most q queries) for distinguishing OMAC from a uniform random function is roughly Lq2/2 n. Here L is the number of blocks of the longest query and n is the output size of the uniform random function. The so far best bound is roughly σσ2/2 n == O( L2 q2/2 n) and hence our new bound is an improved bound. Our improved security analysis also works for OMAC1 and CMAC which has been recommended by NIST as a candidate of blockcipher based MAC. [ABSTRACT FROM AUTHOR]

Phishing is a form of online identity theft associated with both social engineering and technical subterfuge and is a major threat to information security and personal privacy. Here, the authors present an effective image-based antiphishing scheme based on discriminative keypoint features in Web pages. Their invariant content descriptor, the Contrast Context Histogram (CCH), computes the similarity degree between suspicious and authentic pages. The results show that the proposed scheme achieves high accuracy and low error rates. [ABSTRACT FROM AUTHOR]

This paper proposes a facial and visual speech feature extraction method for automatic person authentication in video. The method proposed in Viola and Jones (2006) is used to detect the face region. Face region is processed in YCbCr color space to determine the locations of the eyes. The system models the non-lip region of the face using a Gaussian distribution, and it is used to locate the center of the mouth. Facial and visual speech features are extracted using multiscale morphological erosion and dilation operations, respectively. The facial features are extracted relative to the locations of the eyes and visual speech features are extracted relative to the locations of the eyes and mouth. Auto-Associative Neural Network (AANN) and Support Vector Machines (SVMs) are analyzed for person authentication. AANN models are used to capture the distribution of facial and visual speech features of a subject. SVMs are used to construct the optimal separating hyperplane for facial and visual speech features. The evidence from face and visual speech modalities are combined using a weighting rule, and the result is used to accept or reject the identity claim of the subject. The performance of the system is evaluated for XM2VTS database. It is seen that the system achieves an Equal Error Rate (EER) of about 0.41% and 0.37% for 50 subjects using AANN and SVM, respectively. Finally, the performance of the AANN and SVM models for person authentication are compared. Experimental results show that the SVM gives better performance than the AANN model. [ABSTRACT FROM AUTHOR]

This paper presents a new user dependent approach in iris recognition systems. In the proposed method, consistent bits of iris code are calculated, based on the user specifications, using the user's mask. Another contribution of our work is in the iris segmentation phase, where a new pointwise level set approach with area preserving has been used for determining inner and outer iris boundaries, both exclusively performed in one step. Thanks to the special properties of this segmentation technique, there is no constraint about angles of head tilt. Furthermore, we showed that this algorithm is robust in noisy situations and can locate irises which are partly occluded by eyelid and eyelashes. Experimental results, on three renowned iris databases (CASIAIrisV3, Bath, and Ubiris), show that our method outperforms some of the existing methods, both in terms of accuracy and response time. [ABSTRACT FROM AUTHOR]

The article offers information on the implementation of Performance-focused Service Oriented Network Monitoring Architecture (perfSONAR) as the authentication and authorization architecture for web service-oriented architecture. It states that the perSONAR was developed by through the Gigabit European Advanced Network Technology (GEANT) project through the cooperation of Internet2, Energy Sciences Network (Esnet) of U.S. Department of Energy, and Brazilian National Research and Educational Network. It says that the perSONAR deliver performance measurement through multi-domain environment. It adds that the perfSONAR shows the possibility of an identity federation model for network measurement and administration tools.

The article focuses on the European Fusion Development Agreement (EFDA) federation which is an organisation of fusion research laboratories in Europe which include Commissariat à l'énergie atomique (CEA) of France, JET of Great Britain, and KFKI/HAS of Hungary. It states that Performance Application Programming Interface (PAPI) was implemented as the authentication and authorization infrastructure in all fusion research laboratories for security of data access in all the organisations. It mentions that improvements such as JAVA application integration and single sign off mechanism were achieved. It says that EFDA achieves central web file system, new data access paradigms, and video integration.

The article discusses the lessons that were learned from using the Sloan Digital Sky Survey (SDSS) catalog archive server. Topics include an examination of the advantages to using a database management system (DBMS), such as data integrity and availability, data mining capabilities, and fast query performance, and the authors' recommendations for scientific archive projects that researchers may find useful, such as Central Authentication Service (CAS) usage and traffic logging.

The article focuses on the research about image recognition, considered an important branch of artificial intelligence (AI), conducted in China. It notes that the fundamental research and practical applications of image recognition started in China during the 1960s, reaching 50 years. The fundamental researches include the integration of statistical and syntactic pattern recognition, the introduction of artificial neural networks (ANNs), and the analysis of high-dimensional data. Meanwhile, it notes that the years intended by Chinese researchers on image recognition application helped them to achieve significant developments including the introduction of the optical character recognition, a reliable identity authentication technology, and the intelligent transportation systems (ITS).

Security in wireless sensor networks has become important as they are being developed and deployed for an increasing number of applications. The severe resource constraints in each sensor make it very challenging to secure sensor networks. Moreover, sensors are usually deployed in hostile and unattended environments and hence are susceptible to various attacks, including node capture, physical tampering, and manipulation of the sensor program. Park and Shin [2005] proposed a soft tamper-proofing scheme that verifies the integrity of the program in each sensor device, called the program integrity verification (Ply), in which sensors authenticate PIV servers (PIVSs) using centralized and trusted third-party entities, such as authentication servers (ASs). This article presents a distributed authentication protocol of PIVSs (DAPP) without requiring the commonly used ASs. DAPP uses the Blundo scheme [Blundo et al. 1992] for sensors and PIVSs to establish pairwise keys and for PIVSs to authenticate one another. We also present a protocol for PIVSs to cooperatively detect and revoke malicious PIVSs in the network. We implement and evaluate both DAPP and PIV on Mica2 Motes and laptops, showing that DAPP reduces the sensors' communication traffic in the network by more than 90% and the energy consumption on each sensor by up to 85%, as compared to the case of using a centralized AS for authenticating PIVSs. We also analyze the security of DAPP under various attack models, demonstrating its capability in dealing with diverse types of attacks. [ABSTRACT FROM AUTHOR]

The article evaluates a few protocols that have been suggested for use of radio frequency identification (RFID) tagged systems and identifies vulnerabilities that may be present. According to the authors, these protocols include single-round and multiple-round protocols for a single tag. The article then provides a brief background on privacy/security related issues in RFID tag implementations. When appropriate, the authors present modifications of existing protocols to prevent identified vulnerabilities .

In the fragile/semifragile digital image watermarking for image authentication, fragility or sensitivity of the embedded watermark to malicious attacks is an important problem. On the other hand, robustness to some incidental manipulations, such as JPEG compression, is required for the semifragile watermark. Recently, a binary-phase-only-filter (BPOF)-based watermarking technique has been proposed for image authentication, where the authors embedded a watermark upon the BPOF of the Fourier spectrum of an image into the corresponding magnitude. Then, they performed image authentication by calculating the correlation between the extracted watermark and the phase information computed from the watermarked image. In this paper, we propose to use the identical ratio (IR) between the extracted watermark and the computed BPOF to detect watermark and measure the degree of authenticity. The IR is simpler, computationally efficient, and yields better watermark-detection performance when compared to the correlation-based calculation. In addition, it is found that the technique works better for fragile watermarking when compared to the semifragile watermarking. Furthermore, to accommodate semifragile watermarking, we propose to use the low-frequency ranges for watermark embedding and detection, which improves the required fragility and robustness. The performance of the improved algorithm is verified via experimental results. [ABSTRACT FROM AUTHOR]

The problem of non-interactive message authentication using an insecure broadband channel and an authenticated narrow-band channel is considered. This problem has been considered in the context of ad hoc networks, where it is assumed that there is neither a secret key shared among the two parties nor a public-key infrastructure in place. A formal framework for protocols of this type is presented, along with a new protocol which is as efficient as the best previous protocols. The security of the proposed protocol is based on a new property of hash functions called ‘hybrid-collision resistance’. [ABSTRACT FROM AUTHOR]

In this paper, a field authentication scheme, suitable for providing more efficient operations within an encrypted database, is introduced and discussed. Applying the concept of this proposed scheme, the database will be safeguarded and protected for situations such as a ciphertext search attack, a plaintext substitution attack, and/or a ciphertext substitution attack. In addition, this proposed scheme can be used to facilitate the “projections” operation executed in the database while also allowing the individual field value to be decrypted and authenticated. It is also important to note that the “selection” operation can be directly applied to the resultant database without the tediousness of going through the decryption process by using the random filters concept in the field authentication. Furthermore, the use of the aforementioned concept can eliminate exposure of some unqualified records and, as a result, speed up the process of executing the query. [Copyright &y& Elsevier]

Abstract: This paper improves a recently proposed hardcopy watermarking method by introducing new approaches to decode the embedded information. The proposed method, coined as text luminance modulation (TLM), embeds hidden data in office-like documents, while presenting robustness to the print–scan (PS) channel. The hidden data is embedded by slightly modulating the luminance of characters and symbols. This change can be set unperceivable to the human eye and detected with the aid of a scanner. In previous works, the hidden data was retrieved by using the average luminance level or the halftone pattern as a detection metric. In this paper, however, the detection process combines different metrics into a single metric, significantly improving the detection performance. This paper proposes a new PS model where characteristics induced by the halftoning in the printing process are considered, allowing the use of the variance of a character as a new detection metric. Performance analyses validate the proposed PS model. Experiments illustrate the precision of the analyses and the applicability of the method. [Copyright &y& Elsevier]

The article presents a study which analyzes the certification of computer algorithms. Software reliability decrements the possibility of having computer bugs on the implementation of an algorithm. Certification of algorithms reduces the risks of having erroneous answers that were made by bugs while the implementation is being carried out. A discussion on the authentication of induced subgraphs is also provided.

We define authenticated video as decoded video that results from those received packets whose authenticities have been verified. Generic data stream authentication methods usually impose overhead and dependency among packets for verification. Therefore, the conventional rate-distortion (R-D) optimized video streaming techniques produce highly sub-optimal R-D performance for authenticated video, since they do not account for the overhead and additional dependencies for authentication. In this paper, we study this practical problem and propose an Rate-Distortion-Authentication (R-D-A) optimized streaming technique for authenticated video. Based on packets' importance in terms of both video quality and authentication dependencies, the proposed technique computes a packet transmission schedule that minimizes the expected end-to-end distortion of the authenticated video at the receiver subject to a constraint on the average transmission rate. Simulation results based on H.264 JM 10.2 and NS-2 demonstrate that our proposed R-D-A optimized streaming technique substantially outperforms both prior (authentication-unaware) R-D optimized streaming techniques and data stream authentication techniques. In particular, when the channel capacity is below the source rate, the PSNR of authenticated video quickly drops to unacceptable levels using conventional R-D optimized streaming techniques, while the proposed R-D-A Optimization technique still maintains optimized video quality. Furthermore, we examine a low-complexity version of the proposed algorithm, and also an enhanced version which accounts for the multiple deadlines associated with each packet, which is introduced by stream authentication. [ABSTRACT FROM AUTHOR]

This paper proposes an infrastructure and related algorithms for the controlled and cooperative updates of XML documents. Key components of the proposed system are a set of XML-based languages for specifying access-control policies and the path that the document must follow during its update. Such path can be fully specified before the update process begins or can be dynamically modified by properly authorized subjects while being transmitted. Our approach is fully distributed in that each party involved in the process can verify the correctness of the operations performed until that point on the document without relying on a central authority. More importantly, the recovery procedure also does not need the participation of a central authority. Our approach is based on the use of some special control information that is transmitted together with the document and a suite of protocols. We formally specify the structure of such control information and the protocols. We also analyze security and complexity of the proposed protocols. [ABSTRACT FROM AUTHOR]

The article features a discussion on Web service ecosystems. A Web service ecosystem is a logical collection of Web services whose exposure and access are subject to constraints characteristic of business service delivery. In these ecosystems, service consumers procure services through different distribution and delivery channels, outsourcing service delivery functions such as payment, authentication, and mediation to specialist intermediarics. Web service ecosystems make explicit the notion of service procurement, separating it from that of conventional service supply.

The article demonstrates the use of Perl::Critic, a system that analyzes Perl source code to search for deviations from code standards. In a given example, Perl Critic is used do detect errors in a code that reads connection information from a comma-separated values (CSV) file. The code uses a connect ( ) method which overrides DBI connect ( ) and does a look-up in a CSV file to get the authentication information and other options.