Predictive Modeling in a VoIP System, Journal of Telecommunications and Information Technology, 2013, nr 4

An important problem one needs to deal with in a Voice over IP system is server overload. One way for preventing such problems is to rely on prediction techniques for the incoming traffic, namely as to proactively scale the available resources. Anticipating the computational load induced on processors by incoming requests can be used to optimize load distribution and resource allocation. In this study, the authors look at how the user profiles, peak hours or call patterns are shaped for a real system and, in a second step, at constructing a model that is capable of predicting trends

VoIP Service Model for Multi-objective Scheduling in Cloud Infrastructure

Voice over IP (VoIP) is very fast growing technology for the delivery of voice communications and multimedia data over internet with lower cost. Early technical solutions mirrored the architecture of the legacy telephone network. Now, they have adopted the concept of distributed cloud VoIP. These solutions typically allow dynamic interconnection between users on any domains. However, providers face challenges to use infrastructure in the best efficient and cost-effective ways. Hence, efficient scheduling and load balancing algorithms are a fundamental part of this approach, especially in presence of the uncertainty of a very dynamic and unpredictable environment. In this paper, we formulate the problem of dynamic scheduling of VoIP services in distributed cloud environments and propose a model for bi-objective optimisation. We consider it as the special case of the bin packing problem, and discuss solutions for provider cost optimisation while ensuring quality of service

The good wife : Lina Loos, Adolf Loos and the making of an idea

This work presents a theoretical and methodological inquiry into the rewards of reconsidering what is commonly understood to be irrelevant in discussions in architecture, in this case a significant protagonist who has remained invisible until now, namely Lina Loos, Adolf Loos's first wife. Her own writing, especially in an article she authors and publishes in 1904, 'Vandals', shows an early concern, exemplified by references to architecture, for a significant Loosian topic: the material manifestation of modernity. Considering this, the text searches for reasons for her absence from the discussion in architecture while arguing for Lina Loos's significance in two of Loos's projects, 'My wife's bedroom' and 'Ornament and Crime'. The text starts by debating Lina Loos-s overall absence from academic discussions until the end of the twentieth century and her still persisting absence from architectural discussions in particular. Given that her writing shows a good grasp on a variety of fin-de-siècle topics, among them the material consequences of modernity, the text continues by searching for possible reasons for her continuing irrelevance within the boundaries of the architectural discussion. In this context, the writing of history, changing schools of thought and authorities are discussed as they provide and manipulate the available and relevant topics and materials, which form the basis for the architectural discussion and determine its outcome. In Lina's case, her status as a woman without professional affiliation contributes to a great degree to her alleged irrelevance in architecture. When she is considered at all in architectural discussions until now, Lina Loos appears as Adolf Loos's muse for the bedroom project in their marital apartment. This concept is debated as hindering the scholarly discussion in architecture from moving beyond an understanding of Lina as the provider of creative inspiration for someone else, onto an understanding of her as an active and significant protagonist. Freeing Lina of her problematic status, both as a woman without professional affiliation and muse, and following cluesiv provided by her biographers and other disciplines, the final discussion entails discussing Lina Loos's role as a significant protagonist in architecture. It is argued that only with her influence as a client, Adolf Loos is able to conceive of the unique aesthetic of 'My wife's bedroom' and, most importantly, to articulate his powerful ideas on ornament, which culminate in his manifesto 'Ornament and Crime'. 'Vandals' and 'Ornament and Crime' are presented as a dialogue between authors, the former enriching Adolf Loos's thoughts by architectural examples. Lina Loos and her piece 'Vandals' are a necessary and significant part of the discussion surrounding 'Ornament and Crime'. What makes Lina Loos especially central is that, beyond her contribution to the outcome of an architectural project as a client, she is a significant protagonist in architectural theory.12

Dynamic MixVoIP

Dynamic optimization based on incoming load analysis and prediction is considered to be an innovative approach in order to prevent the overload of the servers in a Voice over IP system. The ongoing project is in an early stage of study and the followings are the current vision and concept regarding it. The information gathered by inspecting the real system of an IT company, MixVoIP, (probe server and sensors spread inside the cloud) and by analyzing the data provided by the predictive algorithm, will be used to optimize load distribution and resource allocation. The implementation in the real-life environment should lead to an improvement of the service offered but also to a sensible reduction of the associated carbon emissions, e.g. as a result of an improved load management, reduced idle CPU times or optimally exploited resources

Predictive Modeling in a VoIP System

An important problem one needs to deal with in a Voice over IP system is server overload. One way for pre- venting such problems is to rely on prediction techniques for the incoming traffic, namely as to proactively scale the avail- able resources. Anticipating the computational load induced on processors by incoming requests can be used to optimize load distribution and resource allocation. In this study, the authors look at how the user profiles, peak hours or call pat- terns are shaped for a real system and, in a second step, at constructing a model that is capable of predicting trends

VoIP Traffic Modelling using Gaussian Mixture Models, Gaussian Processes and Interactive Particle Algorithms

The paper deals with an important problem in the Voice over IP (VoIP) domain, namely being able to understand and predict the structure of traffic over some given period of time. VoIP traffic has a time variant structure, e.g. due to sudden peaks, daily or weekly moving patterns of activities, which in turn makes prediction difficult. Obtaining insights about the structure and trends of traffic has important implications when dealing with the nowadays cloud-deployed VoIP services. Prediction techniques are applied to anticipate the incoming traffic, for an efficient distribution of the traffic in the system and allocation of resources. The article looks in a critical manner at a series of machine learning techniques. We namely compare and review (using real VoIP data) the results obtained when using a Gaussian Mixture Model (GMM), Gaussian Processes (GP), and an evolutionary like Interacting Particle Systems based (sampling) algorithm. The experiments consider different setups as to verify the time variant traffic assumption

Distributed Adaptive VoIP Load Balancing in Hybrid Clouds

Cloud computing as a powerful economic stimulus widely being adopted by many companies. However, the management of cloud infrastructure is a challenging task. Reliability, security, quality of service, and cost-efficiency are important issues in these systems. They require resource optimization at multiple layers of the infrastructure and applications. The complexity of cloud computing systems makes infeasible the optimal resource allocation, especially in presence of uncertainty of very dynamic and unpredictable environment. Hence, load balancing algorithms are a fundamental part of the research in cloud computing. We formulate the problem of load balancing in distributed computer environments and review several algorithms. The goal is to understand the main characteristics of dynamic load balancing algorithms and how they can be adapted for the domain of VoIP computations on hybrid clouds. We conclude by showing how none of these works directly addresses the problem space of the considered problem, but do provide a valuable basis for our work