Enhanced Multimedia Exchanges over the Internet

Although the Internet was not originally designed for exchanging multimedia streams, consumers heavily depend on it for audiovisual data delivery. The intermittent nature of multimedia traffic, the unguaranteed underlying communication infrastructure, and dynamic user behavior collectively result in the degradation of Quality-of-Service (QoS) and Quality-of-Experience (QoE) perceived by end-users. Consequently, the volume of signalling messages is inevitably increased to compensate for the degradation of the desired service qualities. Improved multimedia services could leverage adaptive streaming as well as blockchain-based solutions to enhance media-rich experiences over the Internet at the cost of increased signalling volume. Many recent studies in the literature provide signalling reduction and blockchain-based methods for authenticated media access over the Internet while utilizing resources quasi-efficiently. To further increase the efficiency of multimedia communications, novel signalling overhead and content access latency reduction solutions are investigated in this dissertation including: (1) the first two research topics utilize steganography to reduce signalling bandwidth utilization while increasing the capacity of the multimedia network; and (2) the third research topic utilizes multimedia content access request management schemes to guarantee throughput values for servicing users, end-devices, and the network. Signalling of multimedia streaming is generated at every layer of the communication protocol stack; At the highest layer, segment requests are generated, and at the lower layers, byte tracking messages are exchanged. Through leveraging steganography, essential signalling information is encoded within multimedia payloads to reduce the amount of resources consumed by non-payload data. The first steganographic solution hides signalling messages within multimedia payloads, thereby freeing intermediate node buffers from queuing non-payload packets. Consequently, source nodes are capable of delivering control information to receiving nodes at no additional network overhead. A utility function is designed to minimize the volume of overhead exchanged while minimizing visual artifacts. Therefore, the proposed scheme is designed to leverage the fidelity of the multimedia stream to reduce the largest amount of control overhead with the lowest negative visual impact. The second steganographic solution enables protocol translation through embedding packet header information within payload data to alternatively utilize lightweight headers. The protocol translator leverages a proposed utility function to enable the maximum number of translations while maintaining QoS and QoE requirements in terms of packet throughput and playback bit-rate. As the number of multimedia users and sources increases, decentralized content access and management over a blockchain-based system is inevitable. Blockchain technologies suffer from large processing latencies; consequently reducing the throughput of a multimedia network. Reducing blockchain-based access latencies is therefore essential to maintaining a decentralized scalable model with seamless functionality and efficient utilization of resources. Adapting blockchains to feeless applications will then port the utility of ledger-based networks to audiovisual applications in a faultless manner. The proposed transaction processing scheme will enable ledger maintainers in sustaining desired throughputs necessary for delivering expected QoS and QoE values for decentralized audiovisual platforms. A block slicing algorithm is designed to ensure that the ledger maintenance strategy is benefiting the operations of the blockchain-based multimedia network. Using the proposed algorithm, the throughput and latency of operations within the multimedia network are then maintained at a desired level

Data Hiding and Its Applications

Data hiding techniques have been widely used to provide copyright protection, data integrity, covert communication, non-repudiation, and authentication, among other applications. In the context of the increased dissemination and distribution of multimedia content over the internet, data hiding methods, such as digital watermarking and steganography, are becoming increasingly relevant in providing multimedia security. The goal of this book is to focus on the improvement of data hiding algorithms and their different applications (both traditional and emerging), bringing together researchers and practitioners from different research fields, including data hiding, signal processing, cryptography, and information theory, among others

Big Data Security (Volume 3)

After a short description of the key concepts of big data the book explores on the secrecy and security threats posed especially by cloud based data storage. It delivers conceptual frameworks and models along with case studies of recent technology

Challenges and Remedies to Privacy and Security in AIGC: Exploring the Potential of Privacy Computing, Blockchain, and Beyond

Artificial Intelligence Generated Content (AIGC) is one of the latest achievements in AI development. The content generated by related applications, such as text, images and audio, has sparked a heated discussion. Various derived AIGC applications are also gradually entering all walks of life, bringing unimaginable impact to people's daily lives. However, the rapid development of such generative tools has also raised concerns about privacy and security issues, and even copyright issues in AIGC. We note that advanced technologies such as blockchain and privacy computing can be combined with AIGC tools, but no work has yet been done to investigate their relevance and prospect in a systematic and detailed way. Therefore it is necessary to investigate how they can be used to protect the privacy and security of data in AIGC by fully exploring the aforementioned technologies. In this paper, we first systematically review the concept, classification and underlying technologies of AIGC. Then, we discuss the privacy and security challenges faced by AIGC from multiple perspectives and purposefully list the countermeasures that currently exist. We hope our survey will help researchers and industry to build a more secure and robust AIGC system.Comment: 43 pages, 10 figure

Steganography Approach to Image Authentication Using Pulse Coupled Neural Network

This paper introduces a model for the authentication of large-scale images. The crucial element of the proposed model is the optimized Pulse Coupled Neural Network. This neural network generates position matrices based on which the embedding of authentication data into cover images is applied. Emphasis is placed on the minimalization of the stego image entropy change. Stego image entropy is consequently compared with the reference entropy of the cover image. The security of the suggested solution is granted by the neural network weights initialized with a steganographic key and by the encryption of accompanying steganographic data using the AES-256 algorithm. The integrity of the images is verified through the SHA-256 hash function. The integration of the accompanying and authentication data directly into the stego image and the authentication of the large images are the main contributions of the work

Multimedia security and privacy protection in the internet of things: research developments and challenges

With the rapid growth of the internet of things (IoT), huge amounts of multimedia data are being generated from and/or exchanged through various IoT devices, systems and applications. The security and privacy of multimedia data have, however, emerged as key challenges that have the potential to impact the successful deployment of IoT devices in some data-sensitive applications. In this paper, we conduct a comprehensive survey on multimedia data security and privacy protection in the IoT. First, we classify multimedia data into different types and security levels according to application areas. Then, we analyse and discuss the existing multimedia data protection schemes in the IoT, including traditional techniques (e.g., cryptography and watermarking) and emerging technologies (e.g., blockchain and federated learning). Based on the detailed analysis on the research development of IoT-related multimedia security and privacy protection, we point out some open challenges and provide future research directions, aiming to advance the study in the relevant fields and assist researchers in gaining a deeper understanding of the state of the art on multimedia data protection in the IoT

Cybersecurity applications of Blockchain technologies

With the increase in connectivity, the popularization of cloud services, and the rise of the Internet of Things (IoT), decentralized approaches for trust management are gaining momentum. Since blockchain technologies provide a distributed ledger, they are receiving massive attention from the research community in different application fields. However, this technology does not provide cybersecurity by itself. Thus, this thesis first aims to provide a comprehensive review of techniques and elements that have been proposed to achieve cybersecurity in blockchain-based systems. The analysis is intended to target area researchers, cybersecurity specialists and blockchain developers. We present a series of lessons learned as well. One of them is the rise of Ethereum as one of the most used technologies. Furthermore, some intrinsic characteristics of the blockchain, like permanent availability and immutability made it interesting for other ends, namely as covert channels and malicious purposes. On the one hand, the use of blockchains by malwares has not been characterized yet. Therefore, this thesis also analyzes the current state of the art in this area. One of the lessons learned is that covert communications have received little attention. On the other hand, although previous works have analyzed the feasibility of covert channels in a particular blockchain technology called Bitcoin, no previous work has explored the use of Ethereum to establish a covert channel considering all transaction fields and smart contracts. To foster further defence-oriented research, two novel mechanisms are presented on this thesis. First, Zephyrus takes advantage of all Ethereum fields and smartcontract bytecode. Second, Smart-Zephyrus is built to complement Zephyrus by leveraging smart contracts written in Solidity. We also assess the mechanisms feasibility and cost. Our experiments show that Zephyrus, in the best case, can embed 40 Kbits in 0.57 s. for US$1.64, and retrieve them in 2.8 s. Smart-Zephyrus, however, is able to hide a 4 Kb secret in 41 s. While being expensive (around US$ 1.82 per bit), the provided stealthiness might be worth the price for attackers. Furthermore, these two mechanisms can be combined to increase capacity and reduce costs.Debido al aumento de la conectividad, la popularización de los servicios en la nube y el auge del Internet de las cosas (IoT), los enfoques descentralizados para la gestión de la confianza están cobrando impulso. Dado que las tecnologías de cadena de bloques (blockchain) proporcionan un archivo distribuido, están recibiendo una atención masiva por parte de la comunidad investigadora en diferentes campos de aplicación. Sin embargo, esta tecnología no proporciona ciberseguridad por sí misma. Por lo tanto, esta tesis tiene como primer objetivo proporcionar una revisión exhaustiva de las técnicas y elementos que se han propuesto para lograr la ciberseguridad en los sistemas basados en blockchain. Este análisis está dirigido a investigadores del área, especialistas en ciberseguridad y desarrolladores de blockchain. A su vez, se presentan una serie de lecciones aprendidas, siendo una de ellas el auge de Ethereum como una de las tecnologías más utilizadas. Asimismo, algunas características intrínsecas de la blockchain, como la disponibilidad permanente y la inmutabilidad, la hacen interesante para otros fines, concretamente como canal encubierto y con fines maliciosos. Por una parte, aún no se ha caracterizado el uso de la blockchain por parte de malwares. Por ello, esta tesis también analiza el actual estado del arte en este ámbito. Una de las lecciones aprendidas al analizar los datos es que las comunicaciones encubiertas han recibido poca atención. Por otro lado, aunque trabajos anteriores han analizado la viabilidad de los canales encubiertos en una tecnología blockchain concreta llamada Bitcoin, ningún trabajo anterior ha explorado el uso de Ethereum para establecer un canal encubierto considerando todos los campos de transacción y contratos inteligentes. Con el objetivo de fomentar una mayor investigación orientada a la defensa, en esta tesis se presentan dos mecanismos novedosos. En primer lugar, Zephyrus aprovecha todos los campos de Ethereum y el bytecode de los contratos inteligentes. En segundo lugar, Smart-Zephyrus complementa Zephyrus aprovechando los contratos inteligentes escritos en Solidity. Se evalúa, también, la viabilidad y el coste de ambos mecanismos. Los resultados muestran que Zephyrus, en el mejor de los casos, puede ocultar 40 Kbits en 0,57 s. por 1,64 US$, y recuperarlos en 2,8 s. Smart-Zephyrus, por su parte, es capaz de ocultar un secreto de 4 Kb en 41 s. Si bien es cierto que es caro (alrededor de 1,82 dólares por bit), el sigilo proporcionado podría valer la pena para los atacantes. Además, estos dos mecanismos pueden combinarse para aumentar la capacidad y reducir los costesPrograma de Doctorado en Ciencia y Tecnología Informática por la Universidad Carlos III de MadridPresidente: José Manuel Estévez Tapiador.- Secretario: Jorge Blasco Alís.- Vocal: Luis Hernández Encina

A Systematic Review on Image Data Protection Methods

Securing data is the main goal of any data security system (DSS). Valuable data must be protected all the time and stored in a very highly secure data storage device. This need has become more critical due to the continuous growth of data size.  Furthermore, non-text data in the form of images, audio, and videos can now be transferred and processed easily and thus become part of sensitive data that needs to be protected. Since there is a need to secure and protect data in any form in order to keep them private and valid, it is expected that there would be many attempts already that have been proposed in the literature for this purpose. This paper reviews a group of these proposed strategies and methods that have been applied to different kinds of DSSs. Challenges and future trends of DSSs are also discussed. A number of main findings are grouped and organized as follows: (1) there are many different kinds of security techniques, each of which offers varying degrees of performance in terms of the amount of data and information that can be managed securely, (2) depending on the architecture of the proposed method, the tactics or strategies of the security system, the kinds of DSSs, as well as a few other factors, some methods are more appropriate for the storage of certain categories of data than others

Artificial Intelligence-Altered Videos (Deepfakes), Image-Based Sexual Abuse, and Data Privacy Concerns

Artificial Intelligence (AI) is a phenomenon that has become embedded in human life, and this symbiotic relationship between technology and humanity is here to stay. One such use of AI is deepfakes. The use of AI for deepfakes is arguably one of the most controversial topics because it raises ethical issues. Deepfakes are images or recordings that have been convincingly altered and manipulated to misrepresent someone as doing or saying something that they did not actually do or say. These manipulations thrive in the political arena and recently in the pornography industry, in which women’s faces are masked onto other bodies to create video illusions that cause non-consensual sexual-image abuse and other harms. It is no surprise that the malicious use of deepfake technology has prompted regulatory legislation like the United States National Defense Authorization Act (NDAA), and the recent ratification of amendments to the Digital Services Act (DSA) on criminalizing malicious deepfakes. Scholars, advocates, and victims continue to call for more specific and stricter laws to regulate deepfakes and assign penalties for non-adherence. This paper presents a timely analysis of deepfake pornography as a type of image-based sexual abuse, and of the position of the law on malicious use of deepfake technology. Data protection concerns under the General Data Protection Regulation, and policy recommendations and measures for redress, control, and eradication are also addressed