Requests In Queue Research Articles

Prototype of the request in the service queue

The development of a visual prototype of an application in a single queue for service is given. The pre-image connects the accounting for the growth of losses due to the duration of waiting with such sides of the importance of the application as urgency and priority. Varieties of change of urgency in time are discussed. The possibility of interpreting service as a lasting good is considered. On this basis, it is proposed to use relative losses as the main measure for determining the place of an application in the queue - the ratio of losses due to waiting to the duration of service. The example shows that the order in which service requests arrive depends on the time when the service facility starts accessing the queue and on the ratio of the service durations of individual requests. For the case of returning the service facility to the request after a forced interruption, the possibility of rivalry with it by other requests in the queue that have not yet arrived for servicing is considered. The possibility of working with the queue when servicing in small parts with a change in serviced requests is shown. For this type of work, expressions for step-by-step calculations are given. Calculations are made for two complicated cases of servicing a queue of five requests with a contradictory combination of the initial data of requests. A diagram of the switching of service facilities between requests is given. Taking into account the four sides of the description of the request in the queue at once provides the prototype with greater flexibility than most widely used queuing disciplines. The proposed prototype can be taken as a basis for building multi-parameter models of applications and algorithms for automatic control of the queue of applications for social, economic and computational applications.

Using Simulation Modeling to Estimate Time Characteristics of a Distributed Computing System

In present time, distributed computing systems with parallel data processing are widely used. During development of such distributed systems problem of analyzing workload and structure parameters impact on system performance is presented. Special attention have to be pointed towards evaluating time spent by requests in queues and effects of prioritization algorithms on it.To evaluate computing system’s time characteristics different modeling methods can be used, most effective of which is simulation modeling. It is important, however, not to just conduct modeling, but to make sure that results are accurate.The purpose of this research is acquiring time characteristics of distributed computing system with use of simulation modeling with certain accuracy and estimation of modeling time required.To achieve this task simulation model was developed, which represents functioning of distributed computing systems in set period and takes into account prioritization algorithm, and workload model, which corresponds with selected computational system class. The GPSS language was used to implement the model. Based on the obtained simulation results, it is possible to compare the impact of different algorithms for processing priority requests depending on the parameters of the workload and structure. To evaluate accuracy of results regenerative method of model analysis was used, which is based on concepts of regenerative process and regeneration points.In this paper results of average time spent by requests in queue in dependence with used prioritization algorithm research are presented, as well as time required to achieve desired accuracy. Due to this, it is possible to reasonably recommend the most advantageous of the considered prioritization algorithms for implementation in the developed computing system, depending on the requirements.The presented approach to the analysis of the functioning of distributed computing systems and the assessment of their temporal characteristics will also undoubtedly be useful in the educational process for teaching students in the courses “Computer systems” and “Simulation modeling”.

Conversion of Classical Queuing Systems to Systems with Time Lag

The results of the classical queuing theory are used to model data transmission systems for various purposes, and the average delay of requests in the queue is used as the main characteristic for this. It is known that the average delay is directly proportional to the variances of random arrival and service intervals, which means its quadratic dependence on the coefficients of variation. Classical QS are applicable only in the case of fixed values of these coefficients of variation, which is a serious limitation. Unlike the classical theory, the article presents the results of research on QS described by the transformed distribution laws with a shift to the right. Such a transformation of the distribution laws with the introduction of a time shift parameter turns Markov QSs into non-Markov systems with delay. Spectral expansions and calculated formulas obtained on their basis for the average delay of requests in queue for sixteen QS with time lag are presented. These systems are obtained using four distribution laws used in queuing theory: exponential, hyperexponential, Erlang and hyper-Erlang. It has been theoretically and practically proven that in systems with time lag, the average delay is less than in classical systems. The resulting calculation formulas for the average delay expand and supplement the capabilities of classical systems. The spectral solutions allows you to calculate the average delay and its higher-order moments for these systems in mathematical packages for a wide range of flow parameters.

A queuing theory based delay-efficient packet scheduler for machine type communication

Lately, there is a drastic change in the telecommunication industry due to emergence of Internet of Things (IoT). Machine to Machine (M2M) plays a very important role in enabling IoT. As the LTE is mainly suitable for Human-to-Human (H2H) communication, MTC faces some challenges in LTE like radio resource management and uplink-scheduling algorithms are not suitable for MTC. In this paper, we use a queuing theory and propose a packet scheduler, which would model the regular and event-driven traffic and schedule the jobs in queue for request processing. Then using the Markov Chain process, we calculate the queue length and determine the blocking probability. If there is high blocking probability and still there are some requests in queue, then those requests will be processed in virtual server for maximum network usage.

Queuing System with Unreliable Servers and Inhomogeneous Intensities for Analyzing the Impact of Non-Stationarity to Performance Measures of Wireless Network under Licensed Shared Access

Given the limited frequency band resources and increasing volume of data traffic in modern multiservice networks, finding new and more efficient radio resource management (RRM) mechanisms is becoming indispensable. One of the implemented technologies to solve this problem is the licensed shared access (LSA) technology. LSA allows the spectrum that has been licensed to an owner, who has absolute priority on its utilization, to be used by other participants (i.e., tenants). Owner priority impacts negatively on the quality of service (QoS) by reducing the data bit rate and interrupting user services. In this paper, we propose a wireless multiservice network scheme model described as a queuing system with unreliable servers and a finite buffer within the LSA framework. The aim of this work is to analyze main system performance measures: blocking probability, average number of requests in queue, and average queue length depending on LSA frequencies’ availability.

Indonesian Sign Language API (OpenSIBI API) as The Gateway Services for Myo Armband

We create an API (Application Programming Interface) for Indonesian Sign Language (Sistem Isyarat Bahasa Indonesia/SIBI) which is called OpenSIBI. In this case study, we use the Myo Armband device to capture hand gesture data movement. It uses five sensors: Accelerometer, Gyroscope, Orientation, Orientation-Euler, and EMG. First, we record, convert and save those data into JSON dataset in the server as data learning. Then, every data request (trial data) from the client will compare them using k-NN Normalization process. OpenSIBI API works as the middleware which integrated to RabbitMQ as the queue request arranger. Every service request from the client will automatically spread to the server with the queue process. As the media observation, we create a client data request by SIBI Words and Alphabeth Game, which allows the user to answer several stages of puzzle-game with Indonesian Sign Language hand gesture. Game-player must use the Myo armband as an interactive device that reads the hand movement and its fingers for answering the questions given. Thus, the data will be classified and normalized by the k-NN algorithm, which will be processed on the server. In this process, data will pass OpenAPI SIBI (which connected to RabbitMQ) to queue every incoming data-request. So, the obtained data will be processed one by one and sent it back to the client as the answer.

Distributed Queuing in Dynamic Networks

We consider the problem of forming a distributed queue in the adversarial dynamic network model of Kuhn, Lynch, and Oshman (STOC 2010) in which the network topology changes from round to round but the network stays connected. This is a synchronous model in which network nodes are assumed to be fixed, the communication links for each round are chosen by an adversary, and nodes do not know who their neighbors are for the current round before they broadcast their messages. Queue requests may arrive over rounds at arbitrary nodes and the goal is to eventually enqueue them in a distributed queue. We present two algorithms that give a total distributed ordering of queue requests in this model. We measure the performance of our algorithms through round complexity, which is the total number of rounds needed to solve the distributed queuing problem. We show that in 1-interval connected graphs, where the communication links change arbitrarily between every round, it is possible to solve the distributed queueing problem in O(nk) rounds using O(log n) size messages, where n is the number of nodes in the network and k <= n is the number of queue requests. Further, we show that for more stable graphs, e.g. T-interval connected graphs where the communication links change in every T rounds, the distributed queuing problem can be solved in O(n+ (nk/min(alpha,T))) rounds using the same O(log n) size messages, where alpha > 0 is the concurrency level parameter that captures the minimum number of active queue requests in the system in any round. These results hold in any arbitrary (sequential, one-shot concurrent, or dynamic) arrival of k queue requests in the system. Moreover, our algorithms ensure correctness in the sense that each queue request is eventually enqueued in the distributed queue after it is issued and each queue request is enqueued exactly once. We also provide an impossibility result for this distributed queuing problem in this model. To the best of our knowledge, these are the first solutions to the distributed queuing problem in adversarial dynamic networks.

Implementation of Job Scheduling Algorithms in a Cloud Computing Environment for B2C Electronic Commerce architecture using GI/G/1 queuing model

Traditional B2C Electronic Commerce architecture instigated using n-Tier Client/Server architecture has continually been sluggish, intricate, and costly. With the advent of Cloud computing environment, the amenities vital for the Electronic Commerce architecture are accomplished by proficient organization, which comprises servers, storage supervision, network skills, and virtualization technologies. The research recommends the Job Scheduling algorithm and its enactment on B2C Electronic Commerce architecture. The algorithm is implemented using GI/G/1 Queuing model, to assess the performance of the proposed algorithm using four queuing parameters, specifically, Average numbers of requests in an B2C E-Commerce architecture, Average numbers of requests in the queue, Average waiting time of requests in an B2C ECommerce architecture, Average waiting time of requests in queue. Finally, the allied simulations and numeral results are provided, to relate the performance of the proposed algorithm.

Research on HLA Optimistic Time Advance Mechanism Based on FQR

With the widely application of High Level Architecture (HLA) standard that supports interoperability and reusability, correct understanding of time management and advance mechanism in HLA has been a concerning difficult problem in the field of distributed simulation. Aiming at the problem, the paper analyzed and compared difference between conservative time advance mechanism and optimistic time advance mechanism. The rollback manager was introduced to implement the optimistic time advance mechanism. The middleware was also applied to deal with the rollback process in simulation model. In order to make fully use of advantages of optimistic synchronization mechanism, Flash Queue Request (FQR) service that provided by HLA was used to arrive at an improved time advance algorithm.

Sensitivity analysis for output performance measures in long-range dependent queueing system

Internet traffic has been shown to exhibit characteristics that are very different from traditional telephone network traffic such as long-range dependence (LRD). Therefore, performance analysis of queueing system in LRD traffic is needed to design reliable networks under the tremendous growth of Internet traffic. In this paper, we evaluate the sensitivity of input distribution on the output performance measures. We conduct a Monte Carlo simulation based on a designed experiment in order to relate four performance measures such as the mean and the expected maximum number of requests in queue, and the mean and the expected maximum time in queue to the degree of LRD in arrival, traffic intensities and the types of distributions in G/G/1 queue. Experimental results show that mis-identification of input distributions has a significant effects on the output performances especially when one of the input distributions has LRD property. For such cases, Weibull distribution overestimated the output performances while lognormal distribution underestimated those of the LRD queues. Scope and purpose In the era of information technology, understanding the nature of queueing system associated with a network traffic is crucial for effective network management. The main feature of arrival and service times in information network traffic is LRD property. Many long-tailed distributions have been applied to the fitting of arrival and service time distributions with LRD property. The main purpose of this paper is to see the exchangability of those long-tailed distributions to LRD distributions. We generate both arrival/service time distributions from Pareto, one of the representative distributions with LRD and fit these distributions with long-tailed distributions such as Weibull and lognormal. The result of our sensitivity analysis is expected to provide the case where careful input data analyses are specially needed for the queueing network management.

Response Time of a Fixed-Head Disk to Transfers of Variable Length

Due to the practical complexity of addressing variable length records placed in arbitrary locations of a fixed-head disk (or drum), and because of difficulty of managing secondary memory space in such cases, variable length records are often stored with their first address at a fixed location of the magnetic support. We present a queuing model of such a scheme, assuming a Poisson arrival stream and arbitrary distributed record lengths. The stationary probability distribution of the number of transfer requests in queue and the expected response time are obtained. Numerical examples illustrating the results are presented.