Content Distribution Applications Research Articles

Toward Next-Generation and Service-Defined Networks: A NovaGenesis Control Agent for Future Internet Exchange Point

The Internet has modified how we interact with the world, disrupting our leisure, work model, and economy. Nonetheless, it presents an ossified architecture and infrastructure that may burden future applications. These limitations have led to the development of future Internet architectures (FIAs), for example, NovaGenesis (NG). Considering recent trend topics such as next-generation networks, software-defined networking, service virtualization, and 5G network slicing, the coexistence of disjointed architectures in a multi-architectural network is the key to supporting applications with diverse requirements. In this article, we present NG data and control planes for a programming protocol-independent packet processor (P4)-based future Internet exchange point (FIXP). This proposal advances the state of the art by delivering a native and efficient NG controller that manages a multi-architecture exchange point on the fly. In this article, the NG controller prototype orchestrates a simulated autonomous system with FIXP to connect NG hosts (and its content distribution application) dynamically. The obtained results validate the solution.

Cache-Enabling UAV Communications: Network Deployment and Resource Allocation

In this article, we investigate the content distribution in the hotspot area, whose traffic is offloaded by the combination of the unmanned aerial vehicle (UAV) communication and edge caching. In cache-enabling UAV-assisted cellular networks, the network deployment and resource allocation are vital for quality of experience (QoE) of users with content distribution applications. We formulate a joint optimization problem of UAV deployment, caching placement and user association for maximizing QoE of users, which is evaluated by mean opinion score (MOS). To solve this challenging problem, we decompose the optimization problem into three sub-problems. Specifically, we propose a swap matching based UAV deployment algorithm, then obtain the near-optimal caching placement and user association by greedy algorithm and Lagrange dual, respectively. Finally, we propose a low complexity iterative algorithm for the joint UAV deployment, caching placement and user association optimization, which achieves good computational complexity-optimality tradeoff. Simulation results reveal that: i) the MOS of the proposed algorithm approaches that of the exhaustive search method and converges within several iterations; and ii) compared with the benchmark algorithms, the proposed algorithm achieves better performance in terms of MOS, content access delay and backhaul traffic offloading.

Robust optimal position detection scheme for relational database watermarking through HOLPSOFA algorithm

Nowadays, relational database watermarking is a challenging problem in many content distribution applications and internet-based application environments. The watermarking scheme for relational databases based on a hybrid algorithm, named as HOLPSOFA is proposed. In HOLPSOFA, the combination of Orthogonal Learning Particle Swarm Optimization and Firefly Algorithm is used. This new approach combines the advantages of Orthogonal Learning particle swarm optimization (OLPSO) and Firefly algorithm (FA), which can find the time-optimal solutions simultaneously. The overall relational database watermarking scheme consists of three stages, (1) Optimal location identification through HOLPSOFA algorithm, (2) Watermark embedding and (3) watermark extraction. The proposed HOLPSOFA algorithm is also compared with OLPSO and Firefly algorithm. The performance of the proposed watermarking method is analyzed through Mean Square Error (MSE) and normalized correlation (NC). Our extensive analysis illustrates that the proposed method is robust against various forms of database attacks, including insertion, deletion and alteration. Computer simulations show that the hybrid algorithm is very effective in diminishing different kind of attacks in terms of MSE and NC than existing algorithms.

Cost-Minimizing Dynamic Migration of Content Distribution Services into Hybrid Clouds

With the recent advent of cloud computing technologies, a growing number of content distribution applications are contemplating a switch to cloud-based services, for better scalability and lower cost. Two key tasks are involved for such a move: to migrate the contents to cloud storage, and to distribute the web service load to cloud-based web services. The main issue is to best utilize the cloud as well as the application provider’s existing private cloud, to serve volatile requests with service response time guarantee at all times, while incurring the minimum operational cost. While it may not be too difficult to design a simple heuristic, proposing one with guaranteed cost optimality over a long run of the system constitutes an intimidating challenge. Employing Lyapunov optimization techniques, we design a dynamic control algorithm to optimally place contents and dispatch requests in a hybrid cloud infrastructure spanning geo-distributed data centers, which minimizes overall operational cost over time, subject to service response time constraints. Rigorous analysis shows that the algorithm nicely bounds the response times within the preset QoS target, and guarantees that the overall cost is within a small constant gap from the optimum achieved by a T-slot lookahead mechanism with known future information. We verify the performance of our dynamic algorithm with prototype-based evaluation.

Watermarking Relational Databases Using Genetic Algorithm with Ring Crossover Technique

Proving ownership rights on outsourced relational databases is a crucial issue in today internet-based application environments and in many content distribution applications. This type of system is non-intrusive, resilient, blind, reversible and suitable for databases of any size with reasonable performance on embedding and extraction. Ownership rights on outsourced relational database are extremely vital subject in today’s internet surroundings and in much content sharing request, because the rapid growth of the internet and related technologies offered an unprecedented ability to access and redistribute digital content. The genetic algorithm is an optimization and search technique based on the principles of genetics and natural selection. Proposed watermarking technique is flexible one to synchronize the error. The main aim of the paper to conquer the most important weakness in previously proposed watermarking techniques. Here threshold-based techniques are used in the watermarking decoding. Six type of cross over are implemented in the genetic algorithm. In order to find the effectiveness and feasibility for the proposed crossover operator, a comparison between the results of different crossover operators used in GA is made through a three type of attacks i.e., deletion attack, alteration attack, insertion attack with various levels. In this paper compare our proposed method with five different methods. From the experimental result it is clearly observed that the proposed method of ring crossover proves better result than existing method. Proposed method gives 100% accuracy even when up to 100% of the data set size tuples were altered, deleted and inserted

Understanding Processing Overheads of Network Coding-Based Content Distribution in VANETs

Content distribution in vehicular networks, such as multimedia file sharing and software updates, poses a great challenge due to network dynamics and high-speed mobility. In recent years, network coding has been shown to efficiently support distribution of content in such dynamic environments, thereby considerably enhancing the performance. However, the related work in the literature has mostly focused on theoretic or algorithmic aspects of network coding so far. In this paper, we provide an in-depth analysis on the implementation issues of network coding in wireless networks. In particular, we study the impact of resource constraints (namely CPU, disk, memory, and bandwidth) on the performance of network coding in the content distribution application. The contribution of this paper is twofold. First, we develop an abstract model of a general network coding process and evaluate the validity of the model via several experiments on real systems. This model enables us to find the key resource constraints that influence the network coding strategy and thus to efficiently configure network coding parameters in wireless networks. Second, we propose schemes that considerably improve the performance of network coding under resource constrained environments. We implement our overhead model in the QualNet network simulator and evaluate these schemes in a large-scale vehicular network. Our results show that the proposed schemes can significantly improve the network coding performance by reducing the coding overhead.

Proactive data dissemination to mission sites

In many situations and domains it is important to deliver information to personnel as they work in the field. We consider a specialized content distribution application in wireless mesh networks. When a new mission arrives--for example, when a fire alarm sounds--data is pushed to storage nodes at the mission site where it may be retrieved locally by responding personnel (e.g., police, firefighters, paramedics, government officials, and the media). It is important that information is available at low latency, when requested or pulled by the personnel. The total latency experienced will be a combination of the push delay (if the personnel arrive at the mission site before all the data can be pushed), and the pull delay. Each delay component will in turn be a function of (1) the hop distance traveled by the data when pushed or pulled and (2) any congestion on the links. In this paper, we define algorithms and protocols that trade-off the push and pull latencies depending on the type of application. Our goal is to choose a storage node assignment minimizing the total latency-based cost. We start with a simple model in which cost is a function of distance, and then extend the model, explicitly taking congestion into account. Since the problem is NP-hard even to approximate, our focus is on developing efficient algorithms and distributed protocols that can be easily deployed in wireless mesh networks. In NS2 simulations, we find that our heuristic algorithms achieve, on average, a cost within at most 15% of the optimum.

Strategies of collaboration in multi-swarm peer-to-peer content distribution

In modern Peer-to-Peer (P2P) content distribution applications, multiple swarms typically exist, each corresponding to the dissemination of one content among interested peers. A common design in the existing P2P applications is to allow peers in one swarm to help each other, while different swarms are only coupled when sharing the upload bandwidth at the dedicated content servers/publishers. In recent years, a number of proposals have emerged which advocate inter-swarm collaboration and resource sharing, where peers in one swarm may contribute their storage and bandwidth resources to help peers in the swarm of another content. Such inter-swarm collaboration can improve content availability and optimize resource utilization in the entire system, at the cost of additional overhead for content preloading and inter-swarm coordination. This paper presents a survey of studies on effective inter-swarm collaboration mechanisms in the existing literature. This paper first discusses strategies of collaboration in P2P file sharing applications, and then presents multi-channel collaborative design for P2P live and Video-on-Demand (VoD) streaming. In particular, this paper elaborates our recent design of collaboration strategies among multiple streaming channels in a P2P VoD system, and shows that the server cost can be reduced by up to 25% while high streaming qualities are guaranteed in the entire system, even during extreme scenarios such as unexpected flash crowds. This paper also discusses representative approaches to implement inter-swarm collaborations in various P2P content distribution systems.

Shortcoming, problems and analytical comparison for flooding-based search techniques in unstructured P2P networks

Peer-to-Peer networks attracted a significant amount of interest because of their capacity for resource sharing and content distribution. Content distribution applications allow personal computers to function in a coordinated manner as a distributed storage medium by contributing, searching, and obtaining digital content. Searching in unstructured P2P networks is an important problem, which has received considerable research attention. Acceptable searching techniques must provide large coverage rate, low traffic load, and optimum latency. This paper reviews flooding-based search techniques in unstructured P2P networks. It then analytically compares their coverage rate, and traffic overloads. Our simulation experiments have validated analytical results.

Monitoring and management of peer-to-peer systems

The peer-to-peer paradigm has had large success in content distribution and multimedia communication applications on the Internet. In a peer-to-peer network, the participating nodes create an infrastructure to provide a desired functionality and offer their resources to host an application in a distributed manner.

Fast subscriber identification based on the zero knowledge principle for multimedia content distribution

In this article, an innovative method is proposed for the realisation of zero knowledge subscriber identification schemes that is suitable for multimedia content distribution applications. The fundamental principle underlying the proposed method is the concept of using one-way Boolean functions as transformations for the zero knowledge identification. This enables the increase of the speed of completion of the identification process by two to three orders of magnitude, compared to the corresponding speed when using modular arithmetic with large numbers. A method for the establishment of one way Boolean functions for zero knowledge identification has been developed. Two examples for the application of the proposed method are presented.

Digital watermarking for relational databases using traceability parameter

Proving ownership right on outsourced relational database is a crucial issue in today's internet-based application environments and in many content distribution applications. We present a mechanism for proof of ownership which is based on the secure embedding of a robust imperceptible watermark in the relational database. It is achieved by formulating a watermarking method, which will watermark only the numeric attributes and introduce the traceability parameter in the watermark detection technique. This monitors the modifications made to the relational database by the attacker. Proposed watermark detection technique is having a time complexity of O(η), where η is the number of tuples in the relational database and this technique is resilient to subset attack, alteration attack and data replacement attack.

Tardos Fingerprinting is Better Than We Thought

Tardos has proposed a randomized fingerprinting code that is provably secure against collusion attacks. We revisit his scheme and show that it has significantly better performance than suggested in the original paper. First, we introduce variables in place of Tardos' hard-coded constants and we allow for an independent choice of the desired false positive (FP) and false negative (FN) error rates. Following through Tardos' proofs with these modifications, we show that the code length can be reduced by more than a factor of two in typical content distribution applications where high FN rates can be tolerated. Second, we study the statistical properties of the code. Under some reasonable assumptions, the accusation sums can be regarded as Gaussian-distributed stochastic variables. In this approximation, the desired error rates are achieved by a code length twice shorter than in the first approach. Overall, typical FP and FN error rates may be achieved with a code length approximately five times shorter than in the original construction.

Watermarking Relational Databases Using Optimization-Based Techniques

Proving ownership rights on outsourced relational databases is a crucial issue in today's internet-based application environments and in many content distribution applications. In this paper, we present a mechanism for proof of ownership based on the secure embedding of a robust imperceptible watermark in relational data. We formulate the watermarking of relational databases as a constrained optimization problem and discuss efficient techniques to solve the optimization problem and to handle the constraints. Our watermarking technique is resilient to watermark synchronization errors because it uses a partitioning approach that does not require marker tuples. Our approach overcomes a major weakness in previously proposed watermarking techniques. Watermark decoding is based on a threshold-based technique characterized by an optimal threshold that minimizes the probability of decoding errors. We implemented a proof of concept implementation of our watermarking technique and showed by experimental results that our technique is resilient to tuple deletion, alteration, and insertion attacks.

FairPeers: Efficient Profit Sharing in Fair Peer-to-Peer Market Places

The technical impact of the Peer-to-Peer (P2P) paradigm on content distribution applications has been proved successful and efficient, when participants cooperation is achieved. Conversely, the business model is not clear: given a copy-protected object, its owner must be paid back for each transaction taking place from a provider to a receiver. The P2P paradigm assumes that a receiver turns into a provider, but it is questionable why she/he should provide properly the content, if the owner wants to be reimbursed. Actual systems introduce fairness, giving incentives (e.g., a differential service, like in BitTorrent) to altruistic peers, with the consequence that the owner of an object is economically damaged everyday. Hence, music and film industry sees P2P techniques as a hostile framework for distributing copy protected content for free: today’s answer of the industry is investing in DRM-based solutions, that are not interoperable between different devices and players. In this paper, we present FairPeers, a P2P market framework, that joins a straightforward intellectual property protection and a fair economic model by maintaining the efficiency typical of P2P file sharing systems. The study is completed with an exhaustive security analysis, and the description of a prototype implementation that shows that the P2P paradigm is mature enough to present to the broadest community new revenue models, simply using available tools and state-of-the-art techniques.

Architecture of a PVR Appliance with 'Long-Tail' Internet-TV Capabilities

The design and implementation of a networked PVR appliance incorporating support for Internet-TV is described. The appliance incorporates support for the bittorrent protocol and employs user tools for content location, management and scheduling which encourage background downloading of content and it is particularly suited for long-tail content distribution applications. The standard bittorrent algorithm has been modified to allow client bandwidth and content storage to be managed from a central content server. With this modified protocol each PVR can function as a combined broadcast and storage node in an Internet-wide distribution system.

Broadcast Encryption Using Probabilistic Key Distribution and Applications

A family of novel broadcast encryption schemes based on probabilistic key pre-distribution are proposed, that enable multiple sources to broadcast secrets, without the use of asymmetric cryptographic primitives. A comprehensive analysis of their efficiencies and performance bounds are presented. The paper also suggests a framework for applications of broadcast encryption, depending on 1) the relationship between the size of the network (or the total number of deployed devices) and the group size, and 2) the nature of the devices (stateless or otherwise) in the deployment. The utility of the proposed broadcast encryption schemes is investigated for securing content distribution applications based on the publish-subscribe paradigm.

A survey of peer-to-peer content distribution technologies

Distributed computer architectures labeled "peer-to-peer" are designed for the sharing of computer resources (content, storage, CPU cycles) by direct exchange, rather than requiring the intermediation or support of a centralized server or authority. Peer-to-peer architectures are characterized by their ability to adapt to failures and accommodate transient populations of nodes while maintaining acceptable connectivity and performance.Content distribution is an important peer-to-peer application on the Internet that has received considerable research attention. Content distribution applications typically allow personal computers to function in a coordinated manner as a distributed storage medium by contributing, searching, and obtaining digital content.In this survey, we propose a framework for analyzing peer-to-peer content distribution technologies. Our approach focuses on nonfunctional characteristics such as security, scalability, performance, fairness, and resource management potential, and examines the way in which these characteristics are reflected in---and affected by---the architectural design decisions adopted by current peer-to-peer systems.We study current peer-to-peer systems and infrastructure technologies in terms of their distributed object location and routing mechanisms, their approach to content replication, caching and migration, their support for encryption, access control, authentication and identity, anonymity, deniability, accountability and reputation, and their use of resource trading and management schemes.