Reliability Evaluation of a Multi-state Network with Multiple Sinks under Individual Accuracy Rate Constraint

Over The Top (OTT) provider detecting bad QoS for their users can not influence on the network by themselves. In the other hand, the Internet Service Providers (ISPs) along the path only see the effect in their own network. The users might agree on reducing a property (e.g., the bandwidth) on contract Service Level Agreements (SLA) with ISP to enhance other properties (e.g., Round Trip Time). This paper proposes a communication mechanism between OTT and its own ISP who could act as a relay with bordering ISPs chaining up to user premises, thus finally obtaining better QoS for the pair OTT/user reducing ISPs load in return. This paper proposes a REST interface for the specific case in which enforced RTT is to be exchanged by reducing available bandwidth as a counterpart, to be extended in future work.

This paper presents the contributions of the phd thesis “Mechanisms for management of SLA for Virtual Software Defined Networks based on QoS Classes”. Over the years the Internet has become the primary means of communication, where the users expect to access the Internet anytime, anywhere, and with a certain quality level. As a consequence, in the past few years the traffic demand to Internet access has increased. However, since the current Internet does not guarantee Quality of Service (QoS) and Quality of Experience (QoE), the companies apply a Service Level Agreements (SLA) with Internet Service Providers (ISPs). In this way, the Internet service providers aim to improve utilization of network resources and service delivery to the users through the deployment of Virtual Networks (VNs) over Software Defined Networks (SDNs), called virtual software defined networks (VSDNs). However, the management of this type of environment still presents open issues. In this context, a set of mechanisms to manage VSDN was developed. The objectives of the developed mechanisms are to negotiate, to deploy and to adapt the VSDNs according to the current state of the network infrastructure and the SLA definition.

The new IP multimedia subsystem (IMS) provides an overlay architecture for IP based core networks and enables the efficient provision of an open set of potentially highly integrated multimedia services (i.e. instant messaging, video conferencing, VoIP, application sharing, etc) on top of possibly different access technologies. However, there will be different domains and IMSs managed by different ISPs (Internet service providers) in the Internet. Each ISP has an SLA (service level agreement) established between its users, which defines what kind of resources and prices was agreed to be offered to each user. However there is no SLA between a visited domain and a mobile user. This paper analyses how to extend the QoS capabilities of the IMS offered to a mobile terminal when it roams among different domains. We propose a framework that integrates QoS and mobility management. This integration envisages the improvement of the overall end-to-end performance and the reduction of management entities in the network. The architecture presents the domain policy manager (DPM) as the decision-making and controller of a domain. The proposed architecture uses policies with inter-domain negotiation. An application scenario to show the framework functionality is described as well as the current status of the implementation.

This chapter introduces a greedy approach for delay monitoring of IP networks. It proposed two-phased monitoring scheme that ensures complete coverage of the network from both links and paths point of views, and it minimizes the monitoring overhead on the underlying production network. In the first phase it computes the locations of monitoring stations such that all network links or paths are covered by the minimal number of stations. Subsequently, in the second phase, it computes the minimal set of probe messages to be sent by each station such that the latency of every routing path can be measured. Unfortunately, both the station selection and the probe assignment problems are NP-hard. However, by using greedy approximation algorithms the scheme finds solutions close to the best possible approximations to both the station selection and the probe assignment problems. Further, the experimental results demonstrate the effectiveness of the presented algorithms for accurately monitoring large networks with very few monitoring stations and probe messages close to the number of network links.

The goal of monitoring contractual service level agreements (SLAs) is to measure the performance of a service, to evaluate whether its provider complies with the level of quality of the service (QoS) that the consumer expects. The aim of this paper is to bring to the system designer's attention the fundamental issues that monitoring of contractual SLAs involves: SLA specification, separation of the computation and communication infrastructure of the provider, service points of presence, metric collection approaches, measurement service and evaluation and violation detection service. The paper develops an architecture and give reasons why currently it is practicable to offer guaranteed QoS only to consumers sharing Internet service providers (ISPs) directly with the service provider.

The full potential of smart cities is not yet realized, and opportunities continue to exist in relation to the business models which govern service provision in cities. In saying this, we make reference to the waste services made available by councils across cities in the United Kingdom (UK). In the UK, smart waste management (SWM) continues to exist as a service trialed across designated cities, and schemes are not yet universally deployed. This therefore exists as a business model which might be improved so that wider roll-out and uptake may be encouraged. In this paper, we present a proposal of how to revise SWM services through integrating the Internet service provider (ISP) into the relationship alongside home and business customers and the city council. The goal of this model is to give customers the opportunity for a more dynamic and flexible service. Furthermore, it will introduce benefits for all parties, in the sense of more satisfied home and business owners, ISPs with a larger customer base and greater profits, and city councils with optimized expenses. We propose that this is achieved using personalized and flexible SLAs. A proof-of-concept model is presented in this paper, through which we demonstrate that the cost to customers can be optimized when they interact with the SWM scheme in the recommended ways.

Bandwidth-aware allocation of resilient Virtual Software Defined Networks

The differentiated services (DiffServ) framework is widely proposed as an efficient method for providing advanced IP services to large‐scale networks, with QoS requirements. However, the provisioning of such services in production networks has proved to be more difficult than initially expected, in defining, setting and verifying appropriate Service Level Agreements (SLAs). GEANT, the Gigabit core pan‐European research network, on a pilot basis introduced ‘Premium IP’ service, offering bounded delay and negligible packet loss to the European National Research & Education Networks (NRENs) that it interconnects. However, large scale provisioning of this new service requires the definition of efficient interaction procedures between administrative domains involved and methods for SLA monitoring. This paper focuses on these issues and presents the experience acquired from the early experiments in GEANT, as an example of hierarchical Gigabit multi‐domain environment, enabled with QoS provisioning to its constituent NRENs. This model scales more efficiently than the common peering Internet Service provider (ISP) commercial paradigm. Finally, we outline other options that promise QoS, such as Layer 2 VPNs in MPLS backbones, with non‐standard (yet) mechanisms. Copyright © 2004 John Wiley & Sons, Ltd.

In the differentiated services (DS) enabled networks, Internet service providers (ISPs) establish service level agreements (SLAs) with their customers. Prices of the SLAs and quality of data transmission services should correspond to the requirements of the customers and operations aims of the ISPs. For this reason, IP domains of the ISPs should contain a control system for setting the selling prices of the SLAs and DS services used for data flows of the SLAs. The control system should consider dynamically both requirements of the customers and quality of end-to-end data transmission services. This task is complex because the customers and operators of other networks may not give useful information to the ISPs for the control task. For this reason, a new fuzzy controller based control system is developed. The system operates using local measurements of ingress routers of IP domains about the behaviour of the customers. It does not inquire the level of satisfaction of the customers about offered data transmission services, or capacities of networks of other operators. The operations of the control system are tested using the Network Simulator 2.Key wordsMulti-service InternetDifferentiated ServicesService Level AgreementsFuzzy controllers

This paper proposes a performance index to evaluate the capability of a maintainable computer network (MCN) that is required to send d units of data from the source to the sink through two paths within time T. The proposed system reliability performance index quantifies the probability that a MCN delivers a sufficient capacity with a maintenance budget no greater than B. Two procedures are integrated in the algorithm — an estimation procedure for estimated system reliability and an adjusting procedure utilizing the branch-and-bound approach for accurate system reliability. Subsequently, the estimated system reliability with lower bound and upper bound, and accurate system reliability can be derived by applying the recursive sum of disjoint products (RSDP) algorithm.

Residential and small business customers often have need for high instantaneous download throughput for their Internet transactions which can exceed the throughput provided by the customer's Internet Service Provider (ISP). At the same time, these peak demand periods are relatively brief and may constitute only a few hours a day. During the non-peak periods, these customers have an unused Internet capacity that could be used by others. In this work, we propose and evaluate a bandwidth aggregation system for wireless routers. This system allows neighboring users to form bandwidth pools from the users' connections to their ISPs, allowing users to achieve aggregated instantaneous bandwidth. By transparently segmenting large Web requests, our approach avoids changes to the users' machines, ISPs, or remote servers. We implement and evaluate such a system and discuss related issues.

Service-level-agreement (SLA) monitoring measures network quality-of-service (QoS) parameters to evaluate whether the service performance complies with the SLAs. It is becoming increasingly important for both Internet service providers (ISPs) and their customers. However, the rapid expansion of the Internet makes SLA monitoring a challenging task. As an efficient method to reduce both complexity and overheads for QoS measurements, sampling techniques have been used in SLA monitoring systems. In this paper, a novel adaptive stratified sampling strategy is developed based on the stratified sampling with optimum allocation to make the QoS monitoring less intrusive and more efficient. Simulations using real traffic traces are conducted, which show that the proposed algorithm achieves better performance than systematic sampling and Poisson sampling

With continuous advancements in the domain of information and communication technologies, large-scale enterprises and the Internet service providers have realized about the limited capacity of data storage available to them. This leads to the concept of sharing of resources among the enterprises by renting these services through the Service Level Agreements (SLAs). Fog Computing is proposed to be an extension of cloud computing architecture where the resources are brought near the end users. Fog computing, in contrast to cloud computing provides services along with the computing resources. To borrow the services, the enterprises have to pay according to their usage of the services or resources. In this paper, two nature inspired algorithms are compared to determine the efficient management of resources so that the cost of resources can be minimized and the billing can be achieved through calculation of the utilized resources. Pigeon Inspired Optimization (PIO) and Enhanced Differential Evolution (EDE) are used to determine the energy consumed by the cloudlets or edge nodes that in turn can be used for estimating the bill through the Time of Use pricing variable. We evaluate both of the aforementioned technique to determine their performance regarding the bill calculation on the basis of usage of fog servers. Simulation results demonstrate that PIO gives significantly better results than EDE in terms of resource utilization whereas for bill reduction EDE outperforms PIO based technique.

End-users, whether at home, within an enterprise, or mobile, require managed Internet services, specially in a model, where Internet Service Providers (ISP) are characterized as service sellers and end-users as service buyers. Today, ISPs acting in similar roles (seller/buyer) establish peering agreements between them to manage services. Can these schemes developed for managing inter-ISP services be extended to managing Internet services to large numbers of end-users?Today, Internet service provisioning determines a market, where legal contracts between users and providers are essential. Effective and efficient combinations of fine-grained monitoring and charging functions are a key to successful service provisioning for endusers. However, it is not clear how these functions will be provided in technical and economical terms.The panel will discuss a number of open issues: Do we need managed services for end-users, especially including charged services? Is there a need to charge differently for different services? How fine-grained can efficient monitoring be? What are the types of technical parameters, such as bandwidth, error rates, and delay, which can be used for pricing services? How can service level agreements be specified within a contract so that they can be monitored and enforced by both the seller and the buyer? The goal of this panel will be to develop an understanding of issues and approaches for the support of Ineternet services from the perspective of a large set of end-users.

The mammoth Internet traffic growth puts a significant load on Internet Service Provider's (ISP) network capacity which impacts a wide range of network Quality of Service (QoS) metrics such as latency, jitter, throughput, packet loss, link utilization, load balancing, and service availability. From the ISP's perspective, understanding the possible impact of the future Internet traffic on its network QoS is critical for provisioning their network capacity in a cost-effective manner while meeting Service Level Agreement (SLA) between an operator and its customers. To achieve the above goal, one needs a mechanism that is capable of taking input from the projected future traffic, assign the forecasted traffic over the end-to-end network, and then analyses the impact on the network's QoS status. In this paper, we developed a novel network planning framework, namely Network Impact Modeling and Analysis (NIMA) that uses novel methods and techniques to alert ISP's network capacity planners on the: (a) links that are subject to high-risk in terms of congestion; (b) impact on latency, jitter, packet loss, and throughput; (c) impact on load balancing; and finally suggests an optimal routing strategy that can improve the overall network health. For simulation purposes, we used Mininet in combination with a floodlight controller for implementation. The experiments are performed on different sized mesh topologies to test the effectiveness of our proposed framework.