Client Requests Research Articles

Green Communications: Techniques and Challenges

Green innovation has drawn a gigantic measure of consideration with the improvement of the advanced world. Correspondingly with the advancement in correspondence innovation the ventures and analysts are centering to make this correspondence as green as would be prudent. In cell innovation the advancement of 5G is the subsequent stage to satisfy the client requests and it will be accessible to the clients in 2020. This will build the vitality utilization by which will result in overabundance emanation of co2. In this paper distinctive methods for the green correspondence innovation and a few difficulties are talked about. These methods incorporate gadget to-gadget correspondence (D2D), huge Multiple-Input Multiple-Output (MIMO) frameworks, heterogeneous systems and Green Internet of Things (IoT).

A stealing mechanism for delegation methods

Modern multi-core architectures exhibit non-uniform memory access (NUMA) behavior, where access by a core to data cached locally on a NUMA node is much faster than access to data cached on a remote node. Prior work has shown that on the NUMA multi-core system, delegation is the highly efficient solution to address the generally poor performance of locking methods on highly contended locks due to delegating the execution of critical section to one thread, reducing the movement of shared data between cores. However, we observe that delegation methods exhibit sub-par single-thread performance due mainly to the overheads of the communication between the server and client threads and request array traversal. To address this problem, this paper proposes a stealing mechanism that under no contention the clients can directly enter the critical section by enabling lock stealing. Meanwhile, under contention it employs delegation protocol by disabling lock stealing. Furthermore, we apply stealing mechanism to the state-of-the-art delegation methods: FFWD and RCL. The evaluation shows that delegation augmented with lock stealing can significantly improve the performance in the non-contended case, while matching the performance of their original counterparts in the contended circumstances.

A Proposed Adaptive Least Load Ratio Algorithm to Improve Resources Management in Software Defined Network OpenFlow Environment

So far, the existing load-balancing schemes (static and dynamic) have not taken over a concise and reasonable mechanism for systematic isolation of the resource counters monitored in the OpenFlow switch periodically. To address the aforementioned issue, the adaptive least load ratio algorithm was proposed and followed a straightforward procedure to generate the best possible decisions based on significant motivation characteristics identified in dynamic load balancing schemes like Least Connection-Based and Least Bandwidth-Based. the study was carried out using the HTTPerf tool as it provided a flexible facility for the generation of various HTTP workloads to evaluate server performance. Results revealed that, while Software defined network was under the influence of client requests load ranging from 0 up to 180 (req/sec), the proposed algorithm confirmed a faster server reply time up to 13.37%, server connection time up to 16.3% and average network throughput was improved up to 8%. Moreover, server CPU utilization time and average queue length were reduced to 2.5% and 14%. respectively. accordingly, and based on what the proposed algorithm has achieved in terms of quantitative performance parameters, it could be adopted in SDN-based data centers.

Innovative Methodology for the Identification of the Most Suitable Additive Technology Based on Product Characteristics

This paper reports the study and development case of an innovative application of the Cloud Manufacturing paradigm. Based on the definition of an appropriate web-based application, the infrastructure is able to connect the possible client requests and the relative supply chain product/process development capabilities and then attempt to find the best available solutions. In particular, the main goal of the developed system, called AMSA (Additive Manufacturing Spare parts market Application), is the definition of a common platform to supply different kinds of services that have the following common reference points in the Additive Manufacturing Technologies (DFAM, Design For Additive Manufacturing): product development, prototypes, or small series production and reverse engineering activities to obtain Computer-Aided Design (CAD) models starting from a physical object. The definition of different kinds of services allows satisfying several client needs such as innovative product definition characterized by high performance in terms of stiffness/weight ratio, the possibility of manufacturing small series, such as in the motorsport field, and the possibility of defining CAD models for the obsolete parts for which the geometrical information is missed. The AMSA platform relies on the reconfigurable supply chain that is dynamic, and it depends on the client needs. For example, when the client requires the manufacture of a small series of a component, AMSA allows the technicians to choose the best solutions in terms of delivery time, price, and logistics. Therefore, the suppliers that contribute to the definition of the dynamic supply chain have an important role. For these reasons, the AMSA platform represents an important and innovative tool that is able to link the suppliers to the customers in the best manner in order to obtain services that are characterized by a high-performance level. Therefore, a provisional model has been implemented that allows filtering the technologies according to suitable performance indexes. A specific aspect for which AMSA can be considered unique is related with the given possibility to access Design for Additive Manufacturing Services through the Web in accordance with the possible additive manufacturing technologies.

Conflict Consulting Clinic as a Method of Practical Training of Humanities Students

Conflictology as an educational program aimed at training specialists in the field of conflict resolution includes not only theoretical aspects, it is focused on modern practice. This stems both from the interdisciplinary subject field of conflict management, which combines the fundamental and applied components, as well as the needs of the labor market and the students themselves. At the same time, being in the circle of social sciences and humanities, conflict management faces the traditional challenges for this industry, associated with the most relevant forms of organizing students’ practical work. The article analyzes the unique experience of the clinical form of organizing the practice of students majoring in conflictology, which has been implemented at St. Petersburg State University for 10 years. The practice of students, organized in the form of a conflict consulting clinic, first of all solves the problem of adapting students to the conditions and requirements of the practical activity of a conflictologist. The authors focus on the issues of correlating the clinical form to the requirements of the newest educational standard. The main forms and stages of students’ work in the clinic are presented. The article describes the opportunities of students in acquiring the skills and abilities in conflict resolution, organizing and conducting the negotiation process, mastering conflict management strategies. The authors conclude that the conflict consulting clinic is a complex pedagogical methodology that includes both in-class and out-of-class forms of student practical activity in working with real cases based on client requests and promoting mediation, as well as teacher supervision with rhythmically organized discussion and correction of students’ actions, which ensures due professionalism and quality services provided by students to external consumers.

Drones-as-a-service: a simulation-based analysis for on-drone decision-making

Drone services are expected to emerge in many areas around the world in the near future and this is generating increasing interest. While there is a proliferation of ideas for various applications that can be delivered via drone services, the subject of drone service provisioning has received relatively less attention and, hence, is not well understood. We envision that a variety of drone applications (e.g. renting a drone as a security guard, to pick up and deliver something or to take an interesting photo) can be delivered as a service, using a common set of underlying service provisioning principles, such as making decisions as to whom to service next. In this paper, we study by simulation how different decision-making strategies for drones impact clients and service providers. In particular, the trade-offs between maximising provider revenue versus maximising a client’s personal satisfaction, and different combinations of factors that influence drone behaviour (e.g. speed, distribution of clients, criteria for judging client requests, service duration, effect of battery and whether drones are allowed to change their target client on-the-fly) are investigated. This research has implications for scholars as well as drone service providers and application developers.

The conceptualization of processes for handling online requests of information resources in academic libraries in South Africa: Experience from an Open Distance e-Learning (ODeL) environment

This article aims to present the Open Distance eLearning library processes for requesting information resources using the Online Public Access Catalogue (OPAC). OPAC is known as a platform used by library clients to check the availability of information resources from the entire library collection. ODeL libraries also use the OPAC, not as a library catalogue, but as a portal for requesting information resources. The processes presented in this articles starts from when the library clients request information resources when the requests reach the library/library staff, how the online requests are handled when received, how they are sent to the requesters, how the information resources are sent back to the library after use by the requesters and the process of receiving the returned information resources.

HTTP-Request Classification in Automatic Web Application Crawling

The problem of automatic requests classification, as well as the problem of determining the routing rules for the requests on the server side, is directly connected with analysis of the user interface of dynamic web pages. This problem can be solved at the browser level, since it contains complete information about possible requests arising from interaction interaction between the user and the web application. In this paper, in order to extract the classification features, using data from the request execution context in the web client is suggested. A request context or a request trace is a collection of additional identification data that can be obtained by observing the web page JavaScript code execution or the user interface elements changes as a result of the interface elements activation. Such data, for example, include the position and the style of the element that caused the client request, the JavaScript function call stack, and the changes in the page's DOM tree after the request was initialized. In this study the implementation of the Chrome Developer Tools Protocol is used to solve the problem at the browser level and to automate the request trace selection.

An Empirical Investigation of Factors Causing Scope Creep in Agile Global Software Development Context: A Conceptual Model for Project Managers

Scope creep is considered as one of the crucial reasons for the failure of traditional software development projects. The ability to manage and control the change elements on a project, particularly the project scope, is a key to project success. The notion of agile process was introduced to tackle the scope change-related challenges such as scope creep. By adopting an agile-footed process, the development organizations can react to the consistent market changes and client requests. However, continuous change accommodation may negatively impact on the success of the targeted project since the project manager mainly focuses on controlling scope change rather than analyzing its impact on the cost and quality. The agile-process advocates have accepted that this situation could happen even following agile methodology, which prompts on compromising the quality, postponed the plans, increases the cost, plan to modify, and diminished the consumer loyalty. Additionally, the scope-related challenge significantly increases, especially when managing scope creep in Global Software Development (GSD) context. Thus, there is a need to focus on scope creep factors in the context of AGSD. Motivated by this, current work aims at identifying the factors causing scope creep in the context of AGSD. To achieve the targeted objectives, we reported the current state-of-the-art related to existing scope creep models in AGSD context. We performed a systematic literature review and an empirical study to address the formulated research questions. The current study also identifies the additional challenges of scope creep from the industrial perspective. Based on the obtained results, the current work proposes a conceptual model for scope creep to assist the agile practitioners to effectively handle the scope creep, which ultimately increases the project success and forecasts change control effect on a software project. Moreover, the proposed conceptual model’s effectiveness is validated through expert judgment and a case study. The obtained promising results ensure the additional aspects of AGSD; hence, the project manager could overcome the project’s overall risk by implementing the proposed model.

Analysis of average waiting time and server utilization factor using queueing theory in cloud computing environment

In industry-academy studies, the cloud computing model goes way above the ground. Cloud has emerged as a fantastic business model for service users and, depending on consumer requirements, can be used pay per usage base. Due to inadequate hardware or software resources, When the quantity of client requests for their high-demand service requirements is large, they prefer to wait in a server queue. As a result, in this study, Reduction in overall waiting time and server utilization factor has been focused on. Comparison has been made on average waiting time and analysis made on server utilization using the M/M/c queuing model.

DATABASE PROTECTION BASED ON WEB APPLICATION FIREWALL

Web applications are increasingly being used in activities such as reading news, paying bills, and shopping online. As these services grow, you can see an increase in the number and extent of attacks on them, such as: theft of personal information, bank data and other cases of cybercrime. All of the above is a consequence of the openness of information in the database. Web application security is highly dependent on database security. Client request data is usually retrieved by a set of requests that request the application user. If the data entered by the user is not scanned very carefully, you can collect a whole host of types of attacks that use web applications to create security threats to the database. Unfortunately, due to time constraints, web application programmers usually focus on the functionality of web applications, but only few worry about security. This article provides methods for detecting anomalies using a database firewall. The methods of penetration and types of hacks are investigated. A database firewall is proposed that can block known and unknown attacks on Web applications. This software can work in various ways depending on the configuration. There are almost no false positives, and the overhead of performance is relatively small. The developed database firewall is designed to protect against attacks on web application databases. It works as a proxy, which means that requests for SQL expressions received from the client will first be sent to the developed firewall, rather than to the database server itself. The firewall analyzes the request: requests that are considered strange are blocked by the firewall and an empty result is returned to the client.

VidCloud

As video-streaming services have expanded and improved, cloud-based video has evolved into a necessary feature of any successful business for reaching internal and external audiences. In this article, video streaming over distributed storage is considered where the video segments are encoded using an erasure code for better reliability. We consider a representative system architecture for a realistic (typical) content delivery network (CDN). Given multiple parallel streams/link between each server and the edge router, we need to determine, for each client request, the subset of servers to stream the video, as well as one of the parallel streams from each chosen server. To have this scheduling, this article proposes a two-stage probabilistic scheduling. The selection of video quality is also chosen with a certain probability distribution that is optimized in our algorithm. With these parameters, the playback time of video segments is determined by characterizing the download time of each coded chunk for each video segment. Using the playback times, a bound on the moment generating function of the stall duration is used to bound the mean stall duration. Based on this, we formulate an optimization problem to jointly optimize the convex combination of mean stall duration and average video quality for all requests, where the two-stage probabilistic scheduling, video quality selection, bandwidth split among parallel streams, and auxiliary bound parameters can be chosen. This non-convex problem is solved using an efficient iterative algorithm. Based on the offline version of our proposed algorithm, an online policy is developed where servers selection, quality, bandwidth split, and parallel streams are selected in an online manner. Experimental results show significant improvement in QoE metrics for cloud-based video as compared to the considered baselines.

Design of AGV human-machine interactive control system

The outdoor intelligent transportation of a pharmaceutical factory requires the workshop to put forward task requirements according to the situation and provide multiple AGVs that can meet both man-machine control and networked scheduling. On the basis of existing AGV, an AGV control method based on human-computer interaction is proposed. First, design the overall architecture of the control system, use the touch screen to design and develop the AGV mobile client and task request client to form an industrial wireless network. The establishment of a network enables the AGV mobile client, task request client and vehicle management system to achieve cross-platform communication. Based on this, the client system sets and controls the AGV, which effectively solves the AGV’s man-machine control and networking scheduling problems. After functional testing and performance verification, the system works stably, with good flexibility and scalability.

Multipath Dynamic Adaptive Streaming over HTTP Using Scalable Video Coding in Software Defined Networking

Dynamic Adaptive Streaming over HTTP (DASH) offers adaptive and dynamic multimedia streaming solutions to heterogeneous end systems. However, it still faces many challenges in determining an appropriate rate adaptation technique to provide the best quality of experience (QoE) to the end systems. Most of the suggested approaches rely on servers or client-side heuristics to improve multimedia streaming QoE. Moreover, using evolving technologies such as Software Defined Networking (SDN) that provide a network overview, combined with Multipath Transmission Control Protocol (MPTCP), can enhance the QoE of streaming multimedia media based on scalable video coding (SVC). Therefore, we enhance our previous work and propose a Dynamic Multi Path Finder (DMPF) scheduler that determines optimal techniques to enhance QoE. DMPF scheduler is a part of the DMPF Scheduler Module (DSM) which runs as an application over the SDN controller. The DMPF scheduler accommodates maximum client requests while providing the basic representation of the media requested. We evaluate our implementation on real network topology and explore how SVC layers should be transferred over network topology. We also test the scheduler for network bandwidth usage. Through extensive simulations, we show clear trade-offs between the number of accommodated requests and the quality of the streaming. We conclude that it is better to schedule the layers of a request into the same path as much as possible than into multiple paths. Furthermore, these result would help service providers optimize their services.

Service quality of building services consultants in building project delivery; clients’ perspectives

The role of consultant services engineers in the construction process is pivotal as they make significant contributions towards successful delivery of construction projects. They are responsible for ensuring that the technical specifications and design standards of mechanical, electrical and plumbing aspects of construction projects are adhered to with due consideration to budget and schedule. The quality of services offered by these consultants have however become a source of worry to clients recently in Nigeria as reflected in variance in the quality of services they render. This study examined clients’ assessment of service quality of consultant services engineers in building project delivery. The study adopted survey research design with a total 121 responses obtained from target respondents using structured questionnaire administered to clients’ organizations. The study adapted the 22 SERVQUAL service quality variables from literature. The study discovered that client’s expectation of service quality of building services consultant exceeded the actual perceived service in building project delivery. Clients are unimpressed with the ability of the consultants to show sincere interest, provision of services at the time promised, the ability to give client specialized services relating to MEP and willingness to help client. Out of date software is being used and clients are rarely satisfied with consultants’ responsiveness and assurance. It is imperative for service consultants to understand client’s expectations and ensure such needs are met in the construction delivery process in order to ensure the service quality gap is eliminated. Finally, there is the need for consultants to be conscientious by timeously responding to all instructions and requests of clients as well as improve reputation which will ultimately pay off in project outcome.

IPoE based campus network IPv4/IPv6 dual-stack admission control design and implementation

With the expansion of the campus network, various security risks have appeared. Most campus networks have implemented AAA, but seldom implemented admission control, which decreases the efficiency of dynamic allocation of IP addresses and makes it possible for users to avoid traffic billing. In order to realize the admission control of IPv4/IPv6 dual-stack network in large-scale campus network, we design and implement IPoE-based dual-stack admission control for the campus network in Tsinghua University. In IPoE, users can obtain IP address by DHCP with Ethernet physical link access. Authentication is achieved through a variety of user authentication methods. IP packets are encapsulated in Ethernet and pass through the access network to BRAS devices. BRAS devices find the user's address assignment information based on the client hardware address and the current Vlan ID after receiving the client's DHCP confirmation request message. Our main contributions include: for the various application scenarios under unified IPv4/IPv6 network, session-level IPoE technology is proposed; with the application of different configuration template in different protocol stack, various account control policy is submitted to AAA servers to achieve multi-type, multi-scenario requirements; to deal with the risk in large scale campus network, BRAS, AAA server, DHCP server can cooperate to realize that only authorized users are permitted to obtain addresses, thus avoid the security threats from unauthorized users; to cope with the high load pressure under large-scale deployment, the whitelist of webportal configured on the BRAS side reduces the load on webportal servers. The actual deployment shows that the dual-stack access authentication system has achieved the design objectives and runs smoothly.

Online Inter-Datacenter Service Migrations

Service migration between datacenters can reduce the network overhead within a cloud infrastructure; thereby, also improving the quality of service for the clients. Most of the algorithms in the literature assume that the client access pattern remains stable for a sufficiently long period so as to amortize such migrations. However, if such an assumption does not hold, these algorithms can take arbitrarily poor migration decisions that can substantially degrade system performance. In this paper, we approach the issue of performing service migrations for an unknown and dynamically changing client access pattern. We propose an online algorithm that minimizes the inter-datacenter network, taking into account the network load of migrating a service between two datacenters, as well as the fact that the client request pattern may change “quickly”, before such a migration is amortized. We provide a rigorous mathematical proof showing that the algorithm is 3.8-competitive for a cloud network structured as a tree of multiple datacenters. We briefly discuss how the algorithm can be modified to work on general graph networks with an $O{\mathrm{(log\vert V\vert)}}$ O ( log | V | ) probabilistic approximation of the optimal algorithm. Finally, we present an experimental evaluation of the algorithm based on extensive simulations.

Pengiriman Video secara Live Streaming Menggunakan Dynamic Adaptive Streaming over HTTP (DASH)

Keterbatasan bandwidth dan fluktuasi trafik pada jaringan menjadi kendala dalam proses pengiriman video. Pada saat ketersediaan bandwidth kecil dan traffic jaringan yang tinggi, proses pengiriman video akan memakan waktu yang lama dikarenakan proses transmisi video yang lambat atau lebih umum disebut dengan buffering. Penelitian ini melakukan evaluasi pengiriman video secara live streaming menggunakan metode Dynamic Adaptive Streaming over HTTP (DASH) pada jaringan LAN. DASH merupakan sebuah protokol streaming adaptive yang mampu menyajikan video dengan kualitas video sesuai kemampuan jaringan pada klien. Implementasi ini dilakukan menggunakan video kompresi H.265 dan proses streaming dilakukan pada jaringan LAN secara live streaming sebanyak 20 klien. Hasil penelitian ini diperoleh nilai throughput pengiriman video mencapai 1,4 Mbps dan nilai delay terbesar 12,5 ms. Persentase permintaan klien terhadap kualitas video tertinggi untuk 1 klien sebanyak 98%. Sedangkan penggunaan 20 klien, permintaan untuk video kualitas tinggi berkurang menjadi 46% yang membuktikan bahwa DASH berhasil diimplementasikan secara live streaming.
 Kata kunci: Video, Live, Streaming, H.265, DASH

Building high throughput permissioned blockchain fabrics

Since the introduction of Bitcoin---the first widespread application driven by blockchains---the interest in the design of blockchain-based applications has increased tremendously. At the core of these applications are consensus protocols that securely replicate client requests among all replicas, even if some replicas are Byzantine faulty. Unfortunately, these consensus protocols typically have low throughput, and this lack of performance is often cited as the reason for the slow wider adoption of blockchain technology. Consequently, many works focus on designing more efficient consensus protocols to increase throughput of consensus. We believe that this focus on consensus protocols only explains part of the story. To investigate this belief, we raise a simple question: Can a well-crafted system using a classical consensus protocol outperform systems using modern protocols? In this tutorial, we answer this question by diving deep into the design of blockchain systems. Further, we take an in-depth look at the theory behind consensus, which can help users select the protocol that best-fits their requirements. Finally, we share our vision of high-throughput blockchain systems that operate at large scales.

A Client Bootstrapping Protocol for DoS Attack Mitigation on Entry Point Services in the Cloud

This paper presents a client bootstrapping protocol for proxy-based moving target defense system for the cloud. The protocol establishes the identity of prospective clients who intend to connect to web services behind obscure proxy servers in a cloud-based network. In client bootstrapping, a set of initial line of defense services receive new client requests, execute an algorithm to assign them to a proxy server, and reply back with the address of the chosen proxy server. The bootstrapping protocol only reveals one proxy address to each client, maintaining the obscurity of the addresses for other proxy servers. Hiding the addresses of proxy servers aims to lower the likelihood that a proxy server becomes the victim of a denial-of-service (DoS) attack. Existing works address this problem by requiring the solution of computationally intensive puzzles from prospective clients. This solution slows the progression of attacks as well as new clients. This paper presents an alternative idea by observing that limited capacity of handling initial network requests is the primary cause of denial-of-service attacks. Thus, the suggested alternative is to utilize cost-effective high-capacity networks to handle client bootstrapping, thus thwarting attacks on the initial line of defense. The prototype implementation of the protocol using Google’s firebase demonstrates the proof of concept for web services that receive network requests from clients on mobile devices.