Estimation‐Based Load‐Balancing with Admission Control for Cluster Web Servers

The growth of the World Wide Web and web‐based applications is creating demand for high performance web servers to offer better throughput and shorter user‐perceived latency. This demand leads to widely used cluster‐based web servers in the Internet infrastructure. Load balancing algorithms play an important role in boosting the performance of cluster web servers. Previous load balancing algorithms suffer a significant performance drop under dynamic and database‐driven workloads. We propose an estimation‐based load balancing algorithm with admission control for cluster‐based web servers. Because it is difficult to accurately determine the load of web servers, we propose an approximate policy. The algorithm classifies requests based on their service times and tracks the number of outstanding requests from each class in each web server node to dynamically estimate each web server load state. The available capacity of each web server is then computed and used for the load balancing and admission control decisions. The implementation results confirm that the proposed scheme improves both the mean response time and the throughput of clusters compared to rival load balancing algorithms and prevents clusters being overloaded even when request rates are beyond the cluster capacity.     

Scalable resource management for high‐performance Web servers

Although many research efforts have been devoted to network congestion in the face of an increase in the Internet traffic, there is little recent discussion on performance improvements for endhosts. In this paper, we propose a new architecture, called scalable socket buffer tuning (SSBT), to provide high‐performance and fair service for many TCP connections at Internet endhosts. SSBT has two major features. One is to reduce the number of memory accesses at the sender host by using some new system calls, called Simple Memory‐copy Reduction (SMR) scheme. The other is equation‐based automatic TCP buffer tuning (E‐ATBT), where the sender host estimates ‘expected’ throughput of the TCP connections through a simple mathematical equation, and assigns a send socket buffer to them according to the estimated throughput. If the socket buffer is short, max–min fairness policy is used. We confirm the effectiveness of our proposed algorithm through both simulation technique and an experimental system. From the experimental results, we have found that our SSBT can achieve up to a 30% gain for Web server throughput, and a fair and effective usage of the sender socket buffer can be achieved. Copyright © 2004 John Wiley & Sons, Ltd.     

Web browsing optimization over 2.5G and 3G: end‐to‐end mechanisms vs. usage of performance enhancing proxies

2.5 Generation (2.5G) and Third Generation (3G) cellular wireless networks allow mobile Internet access with bearers specifically designed for data communications. However, Internet protocols under‐utilize wireless wide area network (WWAN) link resources, mainly due to large round trip times (RTTs) and request‐‐reply protocol patterns. Web browsing is a popular service that suffers significant performance degradation over 2.5G and 3G. In this paper, we review and compare the two main approaches for improving web browsing performance over wireless links: (i) using adequate end‐to‐end parameters and mechanisms and (ii) interposing a performance enhancing proxy (PEP) between the wireless and wired parts. We conclude that PEPs are currently the only feasible way for significantly optimizing web browsing behavior over 2.5G and 3G. In addition, we evaluate the two main current commercial PEPs over live general packet radio service (GPRS) and universal mobile telecommunications system (UMTS) networks. The results show that PEPs can lead to near‐ideal web browsing performance in certain scenarios. Copyright © 2006 John Wiley & Sons, Ltd.     

Performance of delay‐sensitive traffic in multi‐layered satellite IP networks with on‐board processing capability

In this article, performance of delay‐sensitive traffic in multi‐layered satellite Internet Protocol (IP) networks with on‐board processing (OBP) capability is investigated. With OBP, a satellite can process the received data, and according to the nature of application, it can decide on the transmission properties. First, we present a concise overview of relevant aspects of satellite networks to delay‐sensitive traffic and routing. Then, in order to improve the system performance for delay‐sensitive traffic, specifically Voice over Internet Protocol (VoIP), a novel adaptive routing mechanism in two‐layered satellite network considering the network's real‐time information is introduced and evaluated. Adaptive Routing Protocol for Quality of Service (ARPQ) utilizes OBP and avoids congestion by distributing traffic load between medium‐Earth orbit and low‐Earth orbit layers. We utilize a prioritized queueing policy to satisfy quality‐of‐service (QoS) requirements of delay‐sensitive applications while evading non‐real‐time traffic suffer low performance level. The simulation results verify that multi‐layered satellite networks with OBP capabilities and QoS mechanisms are essential for feasibility of packet‐based high‐quality delay‐sensitive services which are expected to be the vital components of next‐generation communications networks. Copyright © 2007 John Wiley & Sons, Ltd.     

Software‐defined network‐based prioritization to avoid video freezes in HTTP adaptive streaming

HTTP adaptive streaming (HAS) is becoming the de facto standard for video streaming services over the Internet. In HAS, each video is segmented and stored in different qualities. Rate adaptation heuristics, deployed at the client, allow the most appropriate quality level to be dynamically requested, based on the current network conditions. It has been shown that state‐of‐the‐art heuristics perform suboptimal when sudden bandwidth drops occur, therefore leading to freezes in the video playout, the main factor influencing users' quality of experience (QoE). This issue is aggravated in case of live events, where the client‐side buffer has to be kept as small as possible in order to reduce the playout delay between the user and the live signal. In this article, we propose a framework capable of increasing the QoE of HAS clients by reducing video freezes. The framework is based on OpenFlow, a widely adopted protocol to implement the software‐defined networking principle. An OpenFlow controller is in charge of introducing prioritized delivery of HAS segments, based on the network conditions and the HAS clients' status. Particularly, the HAS clients' status is obtained without any explicit clients‐to‐controller communication, and thus, no extra signaling is introduced into the network. Moreover, this OpenFlow controller is transparent to the quality decision process of the clients, as it assists the delivery of the segments, but it does not determine the actual quality to be requested. In order to provide a comprehensive analysis of the proposed approach, we investigate the performance of the proposed OpenFlow‐based framework in the presence of realistic Internet cross‐traffic. Particularly, we model two types of applications, namely, HTTP web browsing and progressive download video streaming, which currently represent the majority of Internet traffic together with HAS. By evaluating this novel approach through emulation in several multi‐client scenarios, we show how the proposed approach can reduce freeze time for the HAS clients due to network congestion up to 10 times compared with state‐of‐the‐art heuristics, without impacting the performance of the cross‐traffic applications. Copyright © 2016 John Wiley & Sons, Ltd.     

Recruitment and Retention for Community‐Based eHealth Interventions with Populations of Low Socioeconomic Position: Strategies and Challenges

Given persistent communication inequalities, it is important to develop interventions to improve Internet and health literacy among underserved populations. These goals drove the Click to Connect project, a community‐based eHealth intervention that provided novice computer users of low socioeconomic position with broadband Internet access, training classes, a Web portal, and technical support. In this article, we describe the strategies used to recruit and retain this population, the budgetary implications of such strategies, and the challenges and successes we encountered. Results suggest that personal contact between study staff and participants and provision of in‐depth technical support were central to successful recruitment and retention. Such investments are essential to realize the promise of eHealth with underserved populations.     

Performance analysis of data scheduling algorithms for multi‐item requests in multi‐channel broadcast environments

Nowadays querying multiple‐dependent data items in a request is common in many advanced mobile applications, such as traffic information enquiry services. In addition, multi‐channel architectures are widely deployed in many data dissemination systems. In this paper, we extend a number of data productivity‐based scheduling algorithms and evaluate their performance in scheduling multi‐item requests in multi‐channel broadcast environments. We observe from the experimental results two performance problems that render these algorithms ineffective. Lastly, we discuss possible causes of these problems to give insights in the design of a better solution. Copyright © 2009 John Wiley & Sons, Ltd.     

Web Services‐based network management: approaches and the WSNET system

While the Simple Network Management Protocol (SNMP) is still the dominant protocol for managing network elements in IP‐based networks and the Internet, network managers are acknowledging its limitations with respect to configuration management, application development and decentralization of management tasks. Web Services (WS) have been recently proposed to alleviate these limitations, given their pertinence to both decentralized management paradigms (e.g., CORBA), and XML management systems which provide efficiency in configuration management operations. This paper reviews architectures for WS‐based network management, outlining their advantages and disadvantages. These architectures address management of both individual network elements and composite multi‐device networks. Moreover, the paper introduces the architecture of a prototype system for WS‐based network management, namely WSNET. Along with presentation of the WSNET system, we provide a set of experimental results reporting performance figures for the WSNET system, as well as for systems based on other WS architectures. These figures allow for a comparative evaluation of the various systems, and manifest the benefits of the WSNET implementation. An important conclusion from our work is that WS should be seen as an accompaniment to conventional SNMP management rather than a replacement. However, there are also cases (e.g., need for secure remote access) where WS serve as a core rather than auxiliary solution, given that conventional methods are not applicable. Copyright © 2006 John Wiley & Sons, Ltd.     

The communication model for real‐time web service in telecom domain

Development of services that span over the Internet and Telecom networks is driving significant efforts towards the integration of services offered by Telecom operators. The telecommunications R&D community also starts adapting and developing similar service delivery platforms to offer a wide range of new value‐added services faster and more cost efficiently inspired by the success of Web service technologies for the development and deployment of IT services. In this paper, we have an analysis for Telecom Web services communication requirements and also propose Telecom Web services communication model considering the specific characteristics as state, asynchronous, event‐driven communications in Telecom domain. We focus on the design and implementation details for real‐time Web service communication model in Telecom domain, and as the framework of communication model for Telecom Web services, the enhanced state machine design and implementation, and the messages dispatching design and implementation for Telecom Web services communication model, and also illustrate the third party end call control scenarios. Finally, we give the conclusion and future essential work. Copyright © 2009 John Wiley & Sons, Ltd.     

An efficient and lightweight embedded Web server for Web‐based network element management

An Embedded Web Server (EWS) is a Web server which runs on an embedded system with limited computing resources to serve embedded Web documents to a Web browser. By embedding a Web server into a network device, it is possible to provide a Web‐based management user interface, which are user‐friendly, inexpensive, cross‐platform, and network‐ready. This article explores the topic of an efficient and lightweight embedded Web server for Web‐based network element management. Copyright © 2000 John Wiley & Sons, Ltd.     

A framework to determine the optimal weight parameter of RED in next‐generation Internet routers

Active buffer management can improve the performance of Transmission Control Protocol/Internet Protocol‐based networks. Random early detection (RED), an active queue management scheme, has been proposed by the Internet Engineering Task Force for next‐generation Internet routers. RED uses a number of parameters, such as buffer thresholds, a packet drop probability and a weight parameter. RED suffers from low throughput and large delay/jitter and induces instability in networks. Previous attempts to improve the performance of RED were based on modifying the thresholds and drop probabilities. In this paper, we show that an optimal value of the weight parameter can improve the performance of RED, and then develop a framework to determine the optimal value of the weight parameter. We show that the optimal weight parameter obtained from our framework improves the performance of RED. Copyright © 2008 John Wiley & Sons, Ltd.     

Link repair in managed multi‐domain connections with end‐to‐end quality guarantees

The Internet is a platform providing connection channels for various services. Whereas for services like email the best‐effort nature of the Internet can be considered sufficient, other services strongly depend on service‐specific connection quality parameters. This quality dependence has led to dedicated content distribution networks as a workaround solution for services like YouTube. Such workarounds are applicable to a small number of services only. With the global application of the Internet, the impact of quality of service varies from annoyance due to jitter in VoIP communication to endangering human lives in telemedicine applications. Thus network connections with end‐to‐end quality guarantees are indispensable for various existing and evolving services. In this paper we consider point‐to‐point multi‐domain network connections for which the end‐to‐end quality has to be assured. Our contribution includes the classification of fault cases in general and countermeasures against end‐to‐end performance degradation. By correlating events and reasonable countermeasures, this work provides the foundation for quality assurance during the operation phase of end‐to‐end connections. We put our contribution in the context of a vision of global‐goal‐aware self‐adaptation in computer networks and outline further research areas that require a similar classification to the work provided here. Copyright © 2012 John Wiley & Sons, Ltd.     

Investigation of multicast‐based mobility support in all‐IP cellular networks

To solve the IP mobility problem, the use of multicast has been proposed in a number of different approaches, applying multicast in different characteristic ways. We provide a systematic discussion of fundamental options for multicast‐based mobility support and the definition and experimental performance evaluation of selected schemes. The discussion is based on an analysis of the architectural, performance‐related, and functional requirements. By using these requirements and selecting options regarding network architecture and multicast protocols, we identify promising combinations and derive four case studies for multicast‐based mobility in IP‐based cellular networks. These case studies include both the standard any‐source IP multicast model as well as non‐standard multicast models, which optimally utilize the underlying multicast. We describe network architecture and protocols as well as a flexible software environment that allows to easily implement these and other classes of mobility‐supporting multicast protocols. Multicast schemes enable a high degree of flexibility for mobility mechanisms in order to meet the service quality required by the applications with minimal protocol overhead. We evaluate this overhead using our software environment by implementing prototypes and quantifying handoff‐specific metrics, namely, handoff and paging latency, packet loss and duplication rates, as well as TCP goodput. The measurement results show that these multicast‐based schemes improve handoff performance for high mobility in comparison to the reference cases: basic and hierarchical Mobile IP. Comparing the multicast‐schemes among each other the performance for the evaluated metrics is very similar. As a result of the conceptual framework classification and our performance evaluations, we justify specific protocol mechanisms that utilize specific features of the multicast. Based on this justification, we advocate the usage of a source‐specific multicast service model for multicast‐based mobility support that adverts the weaknesses of the classical Internet any‐source multicast service model. Copyright © 2006 John Wiley & Sons, Ltd.     

LoGos: Internet‐Explorer‐Based Malicious Webpage Detection

Malware propagated via the World Wide Web is one of the most dangerous tools in the realm of cyber‐attacks. Its methodologies are effective, relatively easy to use, and are developing constantly in an unexpected manner. As a result, rapidly detecting malware propagation websites from a myriad of webpages is a difficult task. In this paper, we present LoGos, an automated high‐interaction dynamic analyzer optimized for a browser‐based Windows virtual machine environment. LoGos utilizes Internet Explorer injection and API hooks, and scrutinizes malicious behaviors such as new network connections, unused open ports, registry modifications, and file creation. Based on the obtained results, LoGos can determine the maliciousness level. This model forms a very lightweight system. Thus, it is approximately 10 to 18 times faster than systems proposed in previous work. In addition, it provides high detection rates that are equal to those of state‐of‐the‐art tools. LoGos is a closed tool that can detect an extensive array of malicious webpages. We prove the efficiency and effectiveness of the tool by analyzing almost 0.36 M domains and 3.2 M webpages on a daily basis.     

An eigenvalue‐based edge infrastructure for cloud‐based CDN

In today's dynamic video landscape, an end user needs services to be delivered to any devices anytime with less delay over the Internet. Now users' expectation has changed; they want faster time‐to‐market, cost reduction, and the ability to adjust according to the evolving requirements, which are a limit for the traditional server‐based approach. The explosive growth of the internet multimedia application needs a new approach to content delivery to overcome the limitations of server‐based techniques. Cloud‐based content delivery networks (CCDNs) have recently started to emerge where contents are cached from the cloud storage and delivered through the distribution service to meet quality of services (QoS) of requested services. In this paper, we dealt with CCDN deployment problem and proposed a new eigenvalue‐based edge infrastructure for a network service provider to serve the users with a variation on proximity interest concerning operational cost and user QoS satisfaction. The edge infrastructure designing is a two‐step process: (a) ideal location search for placing edge server and (b) edge server placement and capacity provisioning. The performance of the proposed approach is appraised via modeling and simulation. Performance evaluation outcomes are exhibited to manifest the effectiveness and competitiveness of our approach when compared with existing algorithms.     

Service‐oriented 5G network architecture: an end‐to‐end software defining approach

With the ever‐increasing mobile demands and proliferation of mobile services, mobile Internet has penetrated into every aspect of human life. Although the 4G mobile communication system is now being deployed worldwide, simply evolving or incrementally improving the current mobile networks can no longer keep the pace with the proliferation of mobile services. Against this background, aiming to achieve service‐oriented 5G mobile networks, this article proposes an end‐to‐end software defining architecture, which introduces a logically centralized control plane and dramatically simplifies the data‐plane. The control plane decomposes the diversified mobile service requirements and, correspondingly, controls the functions and behaviors of data‐plane devices. Consequently, the network directly orients towards services, and the devices are dynamically operated according to the service requirements. Therefore, the proposed architecture efficiently guarantees the end‐to‐end QoS and quality of experience. The challenges and key technologies of our architecture are also discussed in this article. Real traces‐based simulations validate the performance advantages of proposed architecture, including energy efficiency and the whole performance. Copyright © 2015 John Wiley & Sons, Ltd.     

Swarm intelligence‐based radio resource management for V2V‐based D2D communication

Internet of Things is a promising paradigm that provides the future network of interconnected devices. Device‐to‐Device (D2D) communication, which is considered as an enabler for vehicle‐to‐everything applications, has become an emerging technology to optimize network performance. In this paper, we study the Radio Resource Management (RRM) issue for D2D‐based Vehicle‐to‐Vehicle communication. The RRM key role is to assure the proficient exploitation of available resources while serving users according to their quality of service parameters. An Ant Colony Optimization (ACO)‐based Resource Allocation (ACORA) scheme is proposed in this paper. Swarm intelligence algorithm ACO is adopted to reduce the computational complexity while realizing satisfactory performance. Simulation results show promising performance of our proposed ACORA scheme.     

Network infrastructure extension using 802.1D‐based wireless mesh networks

Ubiquitous Internet access is becoming a major requirement for end‐users due to the increasing number of services and applications supported over the Internet. Extending the coverage of current Wi‐Fi infrastructures installed in companies, universities and cities, has been considered a solution to help in fulfilling this requirement, namely when it comes to wireless and nomadic Internet access. This paper describes and analyses a new and simple solution, called Wi‐Fi network Infrastructure eXtension (WiFIX), aimed at extending current Wi‐Fi infrastructures. WiFIX is based on standard IEEE 802.1D bridges and a single‐message protocol that is able to self‐organize the network, and it only requires software changes in IEEE 802.11 access points (APs); no changes to IEEE 802.11 stations are needed. Overhead analysis and experimental results show both the higher efficiency of the solution compared to the IEEE 802.11s draft standard and its good performance as far as data throughput, delay and packet loss are concerned. Copyright © 2010 John Wiley & Sons, Ltd.     

Cooperation and end‐to‐end in the Internet

This paper analyzes the motivation and strategies for ensuring cooperative behavior among hosts and customer networks in the Internet and 5G networks. The hypothesis is that better cooperation among the benevolent entities could improve the overall Internet welfare, motivating the need for adoption of cooperative security. However, in state of the art, the prevalent security approach in the Internet is based on self‐help, while the adoption of cooperative methods is progressing slowly. At the same time, the ubiquitous reliance on 5G and mission critical nature of some of the new services, for example, ultrareliable (machine‐to‐machine) communication and Internet of things, requires that 5G will do its best to curb the malicious (noncooperative) behavior from becoming a cause of failure to the legitimate services. In this paper, we relate our analysis of the conditions for sustainable cooperation in the Internet with the famous end‐to‐end principle, and present the hypothesis that there is no end‐to‐end solution to the problem of ensuring cooperation among Internet hosts. Game theory allows studying the outcomes of interactions among the players with conflicting interests. We use it to study the hypothesis and show that introducing the reputation of Internet nodes and customer networks can lead to cooperation, which improves the overall Internet welfare and reduces the payoffs of malicious actors. We study the possible response of noncooperative users with advanced defection strategies and the resulting outcomes. We argue that 5G shall make significant progress towards uprooting the selfish behavior and malicious activities using cooperation and relate it with motivation for providing ubiquitous connectivity and ultrareliable services. The paper concludes by summarizing our earlier work on the application of the proposed methods of cooperation to 5G and the Internet; outlining how cooperation in security is not only desirable but also feasible.     

Bitcoin's dynamic peer‐to‐peer topology

Topology discovery is a prerequisite when investigating the network properties; with the enormous number of Bitcoin users and performance issues, it becomes critical to analyse the network in a fashion that makes it possible to detect all Bitcoin's nodes and understand their behaviour. In massive, dynamic, and distributed peer‐to‐peer (P2P) networks like Bitcoin, where thousands of updates occur per second, it is hard to obtain an accurate topology representing the structure of the network as a graph with nodes and links by using the traditional local measurement approaches based on batches, offline data, or on the discovery of the topology around a small set of nodes and then combine them to discover an approximate network topology. All of which present some limitation when applying them on blockchain‐based networks. In this paper, we propose a topology discovery system that performs a real‐time data collection and analysis for Bitcoin P2P links, which assembles incoming nodes information for deeper graph analysis processing. The topology discovery system allows us to gain knowledge on the Bitcoin network size, the network stability in terms of reachable, churn, and well‐connected nodes, as well as some data regarding the effects of some countries' Internet infrastructure on Bitcoin traffic.