scholarly journals Novel Queueing Model for Multimedia Over Downlink in 3.5G Wireless Network

2017 ◽  
Vol 2 (2) ◽  
pp. 68 ◽  
Author(s):  
Khalid Al-Begain ◽  
Alexander N. Dudin ◽  
Vilena V. Mushko
Keyword(s):  
Wireless Network ◽  
Queueing System ◽  
Buffer Management ◽  
Arrival Process ◽  
Management Scheme ◽  
Time Space ◽  
Buffer Time ◽  
Multimedia Stream ◽  
Shared Channel

In this paper, a model for multimedia transmission over downlink shared channel in 3.5G wireless network is presented. The multimedia stream consists of multiplesubstreams that are aggregated into one real-time and onenonreal-time flows. Correlation with each flow and between flows is assumed. Additionally, we propose a combined time-space priority buffer management scheme to optimise quality of service requirements for each flow. The problem is formulated in terms of a queue with two priority classes, one of which has time priority while the another has space priority. The input is described by the Batch Marked Markovian Arrival Process (BMMAP). Service time distributions are of PH (phase) type dependent on the class of a customer. The buffer is finite, but the customers of a class having higher priority for taking into the service from a buffer (time priority) can occupy only a part of this buffer. Queueing system's behavior is described in terms ofmulti-dimensional continuous time skip-free to the left Markov chain. It allows to exploit an effective algorithm for calculation of the stationary distribution of the queueing system. Loss probability for customers of both classes is calculated. Waiting time distribution for priority customers is calculated.

Demand of Wireless Network and Security in Current Research

2015 ◽  
Vol 14 (6) ◽  
pp. 5809-5813
Author(s):  
Abhishek Prabhakar ◽  
Amod Tiwari ◽  
Vinay Kumar Pathak
Keyword(s):  
Wireless Networks ◽  
Quality Of Service ◽  
Wireless Network ◽  
Network Performance ◽  
Wireless Security ◽  
Human Intervention ◽  
Unauthorized Access ◽  
Quality Of Service Parameters ◽  
Wireless Infrastructure

Wireless security is the prevention of unauthorized access to computers using wireless networks .The trends in wireless networks over the last few years is same as growth of internet. Wireless networks have reduced the human intervention for accessing data at various sites .It is achieved by replacing wired infrastructure with wireless infrastructure. Some of the key challenges in wireless networks are Signal weakening, movement, increase data rate, minimizing size and cost, security of user and QoS (Quality of service) parameters... The goal of this paper is to minimize challenges that are in way of our understanding of wireless network and wireless network performance.

scholarly journals AOIO: Application Oriented I/O Optimization for Buffer Management

Symmetry ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 573
Author(s):  
Xiaochang Li ◽  
Zhengjun Zhai ◽  
Xin Ye
Keyword(s):  
System Performance ◽  
Simulation Experiment ◽  
Buffer Management ◽  
Input Output ◽  
Output Data ◽  
Program Counter ◽  
Efficient Management ◽  
Management Scheme ◽  
Buffer Cache ◽  
Management Schemes

Emerging scale-out I/O intensive applications are broadly used now, which process a large amount of data in buffer/cache for reorganization or analysis and their performances are greatly affected by the speed of the I/O system. Efficient management scheme of the limited kernel buffer plays a key role in improving I/O system performance, such as caching hinted data for reuse in future, prefetching hinted data, and expelling data not to be accessed again from a buffer, which are called proactive mechanisms in buffer management. However, most of the existing buffer management schemes cannot identify data reference regularities (i.e., sequential or looping patterns) that can benefit proactive mechanisms, and they also cannot perform in the application level for managing specified applications. In this paper, we present an A pplication Oriented I/O Optimization (AOIO) technique automatically benefiting the kernel buffer/cache by exploring the I/O regularities of applications based on program counter technique. In our design, the input/output data and the looping pattern are in strict symmetry. According to AOIO, each application can provide more appropriate predictions to operating system which achieve significantly better accuracy than other buffer management schemes. The trace-driven simulation experiment results show that the hit ratios are improved by an average of 25.9% and the execution times are reduced by as much as 20.2% compared to other schemes for the workloads we used.

scholarly journals A queueing model for error control of partial buffer sharing in ATM

1999 ◽  
Vol 5 (4) ◽  
pp. 329-348
Author(s):  
Boo Yong Ahn ◽  
Ho Woo Lee
Keyword(s):  
Error Control ◽  
Approximation Scheme ◽  
Queueing System ◽  
Recursive Method ◽  
Loss Probabilities ◽  
Mean Waiting Time ◽  
System Equations ◽  
The Mean ◽  
Buffer Sharing

We model the error control of the partial buffer sharing of ATM by a queueing systemM1,M2/G/1/K+1with threshold and instantaneous Bernoulli feedback. We first derive the system equations and develop a recursive method to compute the loss probabilities at an arbitrary time epoch. We then build an approximation scheme to compute the mean waiting time of each class of cells. An algorithm is developed for finding the optimal threshold and queue capacity for a given quality of service.

Performance Approximation for Time-Dependent Queues with Generally Distributed Abandonments

2021 ◽  
Author(s):  
Gregor Selinka ◽  
Raik Stolletz ◽  
Thomas I. Maindl
Keyword(s):  
Performance Measures ◽  
Real World ◽  
Queueing System ◽  
Time Dependent ◽  
Interval Length ◽  
Arrival Process ◽  
Real World Data ◽  
World Data ◽  
Extant Literature ◽  
Approximation Quality

Many stochastic systems face a time-dependent demand. Especially in stochastic service systems, for example, in call centers, customers may leave the queue if their waiting time exceeds their personal patience. As discussed in the extant literature, it can be useful to use general distributions to model such customer patience. This paper analyzes the time-dependent performance of a multiserver queue with a nonhomogeneous Poisson arrival process with a time-dependent arrival rate, exponentially distributed processing times, and generally distributed time to abandon. Fast and accurate performance approximations are essential for decision support in such queueing systems, but the extant literature lacks appropriate methods for the setting we consider. To approximate time-dependent performance measures for small- and medium-sized systems, we develop a new stationary backlog-carryover (SBC) approach that allows for the analysis of underloaded and overloaded systems. Abandonments are considered in two steps of the algorithm: (i) in the approximation of the utilization as a reduced arrival stream and (ii) in the approximation of waiting-based performance measures with a stationary model for general abandonments. To improve the approximation quality, we discuss an adjustment to the interval lengths. We present a limit result that indicates convergence of the method for stationary parameters. The numerical study compares the approximation quality of different adjustments to the interval length. The new SBC approach is effective for instances with small numbers of time-dependent servers and gamma-distributed abandonment times with different coefficients of variation and for an empirical distribution of the abandonment times from real-world data obtained from a call center. A discrete-event simulation benchmark confirms that the SBC algorithm approximates the performance of the queueing system with abandonments very well for different parameter configurations. Summary of Contribution: The paper presents a fast and accurate numerical method to approximate the performance measures of a time‐dependent queueing system with generally distributed abandonments. The presented stationary backlog carryover approach with abandonment combines algorithmic ideas with stationary queueing models for generally distributed abandonment times. The reliability of the method is analyzed for transient systems and numerically studied with real‐world data.

scholarly journals Análisis basado en parámetros QoS para el servicio VoIP sobre wireless en un campus universitario [Analysis based on QoS parameters for VoIP service on a wireless network within a university campus]

2014 ◽  
Author(s):  
Alexander Olave ◽  
Luis Felipe Valencia ◽  
Juan Carlos Cuéllar
Keyword(s):  
Quality Of Service ◽  
Wireless Network ◽  
Packet Loss ◽  
Cost Benefit ◽  
Access Point ◽  
University Campus ◽  
Delay Jitter ◽  
Qos Parameters ◽  
La Red

Resumen Voz sobre IP, VoIP, es uno de los servicios con mayor desarrollo bajo plataformas inalámbricas; actualmente se ha iniciado su implementación como alternativa frente a la PSTN (red pública conmutada). El interés por VoIP radica en su relación costo-beneficio, ya que las organizaciones pueden utilizar la misma plataforma de su red de datos para transmitir voz. Por lo anterior, es importante que la organización tenga claro que, para garantizar el buen funcionamiento del servicio de VoIP, es decir para ofrecer QoS, se debe realizar la medición de parámetros que afectan la calidad del servicio como lo son: el retardo, la variación del retardo, el ancho de banda y la pérdida de paquetes. Este artículo analiza y valida los parámetros de QoS necesarios para garantizar el buen funcionamiento del servicio de VoIP sobre la red inalámbrica del campus de la Universidad Icesi. Se realizan pruebas en diferentes escenarios para mostrar que no solo factores como el retardo, y su variación, influyen en la calidad de servicio, sino que también la intensidad de la señal que recibe el cliente desde los puntos de acceso.Palabras Clave: Voz sobre IP, Calidad de servicio, Pérdida de paquetes, Retardo, Variación del Retardo, Intensidad de Señal. Abstract VoIP is one of the services that has been developing over under this type of wireless platforms and today has begun to implement as an alternative to the PSTN (Public Switched Telephone Network). The interest in VoIP is its cost-benefit ratio, and that organizations can use the same platform for their data network to transmit voice. Therefore it is important that the organization is clear that to ensure the smooth operation of the VoIP service, ie provide QoS, you must perform the measurement of parameters that affect the quality of service such as: delay, jitter, bandwidth, packet loss. In this paper we analyze and validate the QoS parameters needed to ensure the smooth operation of VoIP over wireless network on the Icesi University campus. We performed a series of tests in different scenarios to show that not only factors such as delay and jitter influencing the quality of service, but also the client signal strength received from of the AP (Access Point).Keywords: Voice over IP, Quality of service, Packet Loss, Delay, Delay variation, signal intensity.

scholarly journals An Efficient Log Buffer Management Scheme of Flash Memory Through Delay of Merging Hot Data Blocks

2010 ◽  
Vol 10 (1) ◽  
pp. 68-77
Author(s):  
Hak-Chul Kim ◽  
Yong-Hun Park ◽  
Jong-Hyeong Yun ◽  
Dong-Min Seo ◽  
Suk-Il Song ◽  
...  
Keyword(s):  
Flash Memory ◽  
Buffer Management ◽  
Management Scheme

scholarly journals Introducing a Mobility Access Category for IEEE 802.11e

2020 ◽  
Vol 9 (5) ◽  
pp. 1610-1614
Keyword(s):  
Quality Of Service ◽  
Wireless Network ◽  
Ieee 802.11E ◽  
Network Simulator ◽  
Mobile Nodes ◽  
Mobile Stations ◽  
Simulation Scenario ◽  
Simulation Results ◽  
The Impact

With traffic increase in a wireless network beyond its capacity and as the number of connected devices continue to grow, the quality of service (QoS) degrades. In this paper we study the impact of mobility on throughput in the case of an infrastructure wireless network using IEEE 802.11 Wi-Fi standard. Since we found in the literature that the mobility of stations can have an impact on the quality of service, we try to remedy to this by implementing a new access category reserved for mobile stations. First we compare the throughput between static and mobile nodes, both connected to a QoS station. Then we propose our new model that consists of adding a new access category used by mobile nodes regardless of their traffic category. The study was made by simulating different scenarios using Network Simulator-3 (NS-3). We found that the throughput may vary depending on the simulation scenario. The simulation results show that with the proposed solution the mobile nodes can have a better throughput.

Sign in / Sign up

Export Citation Format

Share Document