Packet Scheduling Algorithm Research Articles

Quality of Service- and Fairness-Aware Resource Allocation Techniques for IEEE802.11ac WLAN

Increased demand for high-quality multimedia applications over IEEE802.11 networks has further motivated service providers to improve the QoS (quality of service) for all types of network services. IEEE802.11ac is one of the advanced WLAN standards that provides wideband transmission channels and higher data rates, which are vital to support very high-throughput services. However, due to the use of the CSMA/CA-based random access packet transmission technique, the QoS and service fairness criteria cannot always be maintained, particularly for variable bit rate services. This paper proposes new packet scheduling algorithms to support consistently high QoS and intra-service fairness for high data rate video streams. We name the proposed algorithms FRA - TXOP (Flow Rate Adaptive Transmission Opportunity) and EAS (Enhanced Access Scheduler). These algorithms offer appropriate QoS and fairness to video services in a CSMA/CA network. The FRA - TXOP algorithm allocates the transmission resources according to the channel congestion levels experienced by video flows to improve and maintain consistent QoS values. At the same time, the EAS algorithm offers service fairness among the video streams by appropriately scheduling them on the downlink channel. The EAS algorithm is implemented on top of the FRA - TXOP algorithm to achieve high QoS and service fairness among video streams. An NS-3 simulation model is developed to evaluate the performance of the proposed algorithms. The performance analysis shows that the proposed algorithms enhance the video flow QoS in terms of throughput and packet delay as well as improve the fairness among the video flows compared to other TXOP algorithms.

Minimum Length Minimum Delay Scheduling Using Artificial Butterfly Optimization (ABO) Algorithm in Manet

Recently, the requirement for various real-time applications over Mobile ad-hoc networks (MANETs) has been increasing tremandously. Packet scheduling and routing algorithms are the important factors for improving the Quality of service (QoS) parameters over the MANETs. Still, it is not easy to proficiently aid multimedia broadcast with its stringent delay constraints over MANETs. Moreover, there are several problems in assisting QoS over MANETs owing to interference amid nodes in the network. In this paper, Minimum Length Minimum Delay Scheduling (MLMDS) using Artificial Butterfly Optimization (ABO) algorithm is proposed. A fitness function for ABO is derived in terms of the round trip scheduling delay, the conflict graph and the amount of slots in the data sub-frame. A slot selection algorithm is proposed such that the selected slot is supposed to yield lesser delay and spatial reuse. By simulation results, it has been shown that MLMDS achieves minimum delay with higher throughput.

SharpEdge: an asynchronous and core-agnostic solution to guarantee bounded-delays

What are the key properties that a network should have to provide bounded-delay guarantees for the packets? In this paper, we attempt to answer this question. To that end, we explore the theory of bounded-delay networks and provide the necessary and the sufficient conditions required to have deterministic bounded-delays in the network. We prove that as long as a network is work-conserving, independent of the packet scheduling and queue management algorithms used in the switches, it is sufficient to shape the traffic~\textit{properly} at the edge of the network to meet hard bounded-delays in the network. Using the derived theorems, we present SharpEdge, a novel design to meet deterministic bounded-delays in the network. To the best of our knowledge, SharpEdge is the first scheme that can meet all following key properties: 1) it supports coexistence of different classes of traffic, while it can guarantee their different required bounded-delays 2) it does not require any changes in the core of the network, 3) it supports both periodic and bursty traffic patterns, and 4) it does not require any time synchronization between network devices.

A Study on Packet Scheduling Algorithms for Healthcare Contents over Fifth Generation (5G) Mobile Cellular Network

A Study on Packet Scheduling Algorithms for Healthcare Contents over Fifth Generation (5G) Mobile Cellular Network

Improving network performance with an integrated priority queue and weighted fair queue scheduling

<p>Quality of service (QoS) is the measure of network service availability and transmission. There are many factors influencing QoS among which one is the increasing number of network service users. The increase in the number of network service users and communication traffic causes network congestion. And the traffic congestion results in delay or packet loss and jitter variation. As a result, an organization’s network quality deteriorates and or even becomes unavailable. Therefore, to deliver a high quality network service to the users, a solution that avoids network traffic congestion is needed. In this study, the causes for network traffic congestion and the best solutions to eliminate traffic congestion in a network with congestion management and avoidance using an integrated priority queue (PQ) and weighted fair queue (WFQ) packet scheduling algorithms is proposed.</p>

Modified Proportional Fair Scheduling Algorithm for Heterogeneous LTE-A Networks

Growing of time-sensitive applications such as streaming multimedia, voice over IP and online gaming required strongly support from mobile communication technology. So, the persistent need for wireless broadband technologies such as LTE-A is essential. LTE-A can achieve QoS in an efficient manner by using a reliable packet scheduling algorithm. It also supports good cell coverage by using heterogeneous capability. In this paper, modifications of proportional fair (PF) algorithm are proposed with different methods to compute the average throughput, which is the main and important parameter in the PF cost function. These methods are geometric mean, root mean square and arithmetic mean. Vienna simulator is used to study the performance of the proposed algorithms. A comparison between PF modifications and the most famous algorithms (the original PF and Best CQI algorithms) with various UE velocities is introduced. Average UE throughput, spectral efficiency, energy per bit, cell throughput and fairness are used as performance indicators. The results expose that QPF has best improved values for spectral efficiency, energy per bit and fairness by 8.4%, 14%, and 9.3%, respectively than original PF. However, Best CQI has a better value of average UE and cell throughput than all algorithms of 2% and 1.8% in low and medium UE velocity, respectively, but the best value of all types of throughput at high speed is gained by QPF. QPF and GMPF has the same performance in fairness with all UEs speeds.

Downlink Radio Resource Management Through CoMP and Carrier Aggregation for LTE-Advanced Network

Long Term Evolution-Advanced (LTE-A) offers several new technologies to improve the performance of the user. However, poor received signal and interference from adjacent cells in the cell-edge area can reduce the efficiency of using individual technology. Therefore, the cell-edge users have lower throughput compared to the other users in the cell and LTE-A standard. An efficient downlink radio resource management scheme is proposed in this paper by combining the coordinated multipoint transmission and reception technique along with carrier aggregation technique to achieve higher throughput for the cell-edge user and better overall performance. The proposed method jointly transmits multiple component carriers to the cell-edge user from different cells to increase the bandwidth, strengthen the received signal, and reduce the interference while it satisfies several constraints. Modified largest weighted delay first packet scheduling algorithm is deployed for resource allocation, which takes into account the delay parameters, the probability of packet loss, and data rates of the user. The obtained system-level simulation results show that the proposed method significantly enhances the throughput performances, spectral efficiency, and fairness index, compared with the existing conventional methods.

A performance simulation and verification method of packet scheduling algorithms for data stream based on QoS

A performance simulation and verification method of packet scheduling algorithms for data stream based on QoS

A study of packet scheduling algorithms in long term evolution-advanced

<span lang="EN-GB">The allocation of radio resources is one of the most critical functions performed by the Radio Resource Management (RRM) mechanisms in the downlink Long Term Evolution – Advanced (LTE-Advanced). Packet scheduling concerns itself with allocation of these radio resources in an intelligent manner such that system throughput/capacity can be maximized whilst the required multimedia Quality of Service (QoS) is met. Majority of the previous studies of packet scheduling algorithms for LTE-Advanced did not take the effect of channel impairments into account. However, in real world the channel impairments cannot be obliterated completely and have a direct impact on the packet scheduling performance. As such, this work studies the impact of channel impairments on packet scheduling performance in a practical downlink LTE-Advanced. The simulation results obtained demonstrate the efficacy of RM2 scheduling algorithm over other scheduling algorithms in maximizing the system capacity and is more robust on the effect of the cellular channel impairments. </span>

Implementation of Class-Based Low Latency Fair Queueing (CBLLFQ) Packet Scheduling Algorithm for HSDPA Core Network

To provide a guaranteed Quality of Service (QoS) to real-time traffic in High-Speed Downlink Packet Access (HSDPA) core network, we proposed an enhanced mechanism. For an enhanced QoS, a Class-Based Low Latency Fair Queueing (CBLLFQ) packet scheduling algorithm is introduced in this work. Packet classification, metering, queuing, and scheduling using differentiated services (DiffServ) environment was the points in focus. To classify different types of real-time voice and multimedia traffic, the QoS provisioning mechanisms use different DiffServ code points (DSCP).The proposed algorithm is based on traffic classes which efficiently require the guarantee of services and specified level of fairness. In CBLLFQ, a mapping criterion and an efficient queuing mechanism for voice, video and other traffic in separate queues are used. It is proved, that the algorithm enhances the throughput and fairness along with a reduction in the delay and packet loss factors for smooth and worst traffic conditions. The results calculated through simulation show that the proposed calculations meet the QoS prerequisites efficiently.

A novel localised network coding-based overhearing strategy

Network coding is a very effective approach to improve network throughput and reduce end-to-end delay. However, the existing approaches cannot thoroughly solve the problem of how to deal with newly overheard packets when the buffer is full, meanwhile, coding node does not schedule the packets in coding queue according to the packets' information in overhearing buffer. As a result, these methodologies lack flexibility and require quite a few assumptions. To address these limitations, we propose a new network coding overhearing strategy which is based on data packet switching and scheduling (DPSS) algorithm. First, when overhearing buffer is full and the sink nodes have overheard new packets, sink nodes will drop the recently overheard packets but record their IDs; second, sink nodes report the packets' information to the coding node that schedules the packets in coding queue for ease of encoding. Finally, sink nodes delete the packets which have been used for decoding, and call for the ever dropped packets when decoding ratio reaches the threshold. Theoretical analysis and simulation demonstrate that, compared with traditional overhearing policies, our scheme gets higher coding ratio and less delay.

An improved downlink packet scheduling algorithm for delay sensitive devices in both H2H and M2M communications in LTE-advanced networks

An improved downlink packet scheduling algorithm for delay sensitive devices in both H2H and M2M communications in LTE-advanced networks

Service assurance packet-scheduling algorithm for a future aeronautical mobile communication system

In recent years, realizing safe and efficient air traffic management (ATM) has become one of the most important social issues because of the rapid increase in air traffic volume. To realize safe and efficient ATM, it is necessary for related stakeholders to share aeronautical big data by connecting to aircrafts and ground systems efficiently and globally. However, the current aeronautical communication systems are not adapted to be used in support of global collaborative decision making (CDM) through information exchange. In order to accelerate the implementation of information collaborative environment and improve operational awareness in the aeronautical domain, this study focuses on an information platform for sharing aeronautical big data, and a communication medium for achieving Internet of aeronautical things. This paper proposes a new packet-scheduling algorithm for a next-generation aeronautical mobile communication system that includes various types of services and devices. The algorithm balances service assurance and service fairness using strict priorities for real-time services and loose priorities for non-real-time services. Performance evaluations were conducted using a network simulator to confirm the effectiveness of the proposed algorithm. First, a simple single-device scenario was utilized to confirm the effectiveness of the quality of service function for an aeronautical mobile communication system. Second, a multiple-device scenario was employed to evaluate the performance of the proposed scheduler. Finally, an airport scenario was used to demonstrate the effectiveness of our algorithm in a more practical situation. Furthermore, we show that the airport scenario is useful for evaluating the overall performance of a new aeronautical mobile communication system in the system introduction phase or cell design phase.

Fast and Secure Packet Scheduling with Packet Level Redundancy Elimination in Dynamic Mobile Networks

Mobile networks are fast and flexible for effective communication, where it only needs a dynamic topology and unstructured network construction. Due to this flexible nature, the resource utilization and energy consumption is high when comparing to the other static networks. In this scenario, packet redundancy is major problem on mobile networks, which increases network traffic and energy. Currently redundancy elimination is performed using redundancy elimination (RE) solution, which affects the end-to-end privacy. To eliminate redundant packet transfers and provide fast and secure packet transfer in the dynamic mobile network, a new middle box framework is proposed in this paper. This framework is named as Sift Hub, which is a centre point to verify the packet redundancy and security violations. This includes four algorithms to perform packet redundancy elimination, packet scheduling and verification. The algorithms are One pass signature generation algorithm (OSGA) for packet security, Predictive encryption technique using enhanced hidden vector encryption algorithm for redundancy detection on encrypted traffic, Packet level data filtering algorithm (PLDF) for eliminating un-authenticated and redundant packets and RAPS-Redundancy aware packet scheduling algorithm for fast data scheduling over dynamic mobile networks. The Shift_Hub supports inter and intra packet level redundancy elimination and secure packet scheduling without affecting the end-to-end privacy. The Shift_Hub is implemented and the performance is evaluated on dynamic mobile network scenario created on NS2 simulator. The results shows, the proposed work gives better performance in finding and eliminating redundant packet in secure manner than the existing works.

Coflow Scheduling in the Multi-Resource Environment

In data centers, a lot of cluster computing applications follow the coflow working pattern. That is, a collection of flows between two groups of machines is semantically related. On the other hand, network function virtualization sufficiently improves the performance of data center networks. It however complicates the network environment by introducing many multi-function middleboxes each with multiple resources. Coflows encounter extremely different processing delays under diverse network functions. Prior coflow scheduling schemes are insufficient to guarantee the coflow completion time in the multi-resource environment. In this paper, we propose, model, and analyze the coflow scheduling problem in the multi-resource environment. We present a dedicated method, data rate guarantee for coflow (DRGC), to guarantee the data rate requirements of coflows in this situation. DRGC prioritizes the coflow scheduling sequence, assigns precise data rates for coflows, and deploys a packet scheduling algorithm at middleboxes to guarantee their transmissions. In our experiments, DRGC efficiently guarantees the completion times of coflows and supports 15% more workload, compared with other scheduling schemes.

Cross-Layer Performance Analysis of Downlink Multi-Flow Carrier Aggregation in Heterogeneous Networks

Multi-flow carrier aggregation (CA) is an emerging technique that is implemented to improve the capacity of cellular networks. In this paper, we study the cross-layer performance of user equipments (UEs) in heterogeneous networks under multi-flow CA. We develop a queuing analytical model for measuring packet-level performance parameters, e.g., packet loss probability and queuing delay. Our developed model accounts for the time-varying channels, the channel scheduling algorithm, partial channel quality information feedback, and the number of component carriers deployed at each tier. Our model also takes into consideration stochastic packet arrivals, the packet scheduling algorithm, and out-of-sequence packet delivery. The developed model can be used to tune the various system and operating parameters in order to offload traffic from the macrocells to the small cells while maintaining the quality of service requirements of UEs. The accuracy of the analytical model developed in this paper is validated through computer simulations.

Toward Delay-Based Utility Maximization: Modeling and Implementation in an SDWN Platform

Packet (link) scheduling algorithms in wireless networks should be able to maximize the networks' transmission capability while maintaining an acceptable delay and fairness performance. Maximum-weight (MW) policies based on the delay index are throughput-optimal in a wireless network. However, sampling the real-time head-of-line (HOL) packet statistics is still challenging. We model the delay as a function of the arrival rate and service rate, and this model enables the scheduling algorithms to obtain the packet delay without high-frequency sampling. Then, we model the delay-related performance problems in everyday life as a utility-maximization problem. By utilizing the Lyapunov optimization, we transform the initial problem into a queue stability problem and design an MW algorithm to solve it. The solution can ensure deterministic long-term average delay guarantees. Moreover, its throughput utility differs from the optimally fair value by an amount that is inversely proportional to the delay guarantee. We evaluate the theoretical performance via simulations. We also build a real-world software-defined wireless network platform and implement our algorithm on it to evaluate the algorithm's actual performance. The experimental results show that our method outperforms the state-of-the-art algorithm in terms of throughput by up to 13.83%, and it outperforms the default first-in, first-out (FIFO) method by up to 40.41%.

An improved downlink packet scheduling algorithm for delay sensitive devices in both H2H and M2M communications in LTE-advanced networks

The demand for increased data rate with improved QoS for real-time data traffic is ever increasing in the present day wireless environment. The scheduling schemes available in the literature incur lot of scheduling overhead at the eNodeB. Therefore, this work recommends an energy efficient, QoS-aware scheduler with reduced scheduling complexity at the eNodeB, for transmission of delay sensitive data. The scheduling problem is composed as a gain of weighted transmission rates of all possible combinations of various resources required by the channel for transmitting data. An improved greedy algorithm at the eNodeB, has been developed to allocate the resources dynamically to the user equipments (UEs) for the transmission of real-time data. The input video frames to the algorithm are compressed using discrete wavelet transform. The results of this research work show that the proposed scheduling algorithm greatly improves the coverage of the cell edge users. The performance of this greedy scheduler is compared with other two notable schedulers in the literature namely LOG rule and EXP-rule. This scheduling algorithm outperforms the other schemes in terms of QoS parameters for real-time data transmission.

Congestion Control and Packet Scheduling for Multipath Real Time Video Streaming

Real time video traffic has stringent delay requirement and is bandwidth demanding when streaming over the internet. Single path transmission may provide unsatisfactory picture quality to users due to packet loss, jitter, and low bandwidth. Multipath transmission is another option to achieve better service by aggregating bandwidth and exploiting path diversity. As utility maximization theory shows, to achieve better satisfaction is to provide higher throughput and lower frame delivery delay for real time video traffic. The congestion control is responsible to probe maximum available bandwidth and packet scheduling is to take advantages of path diversity, which are two key research points in multipath context and are also the main concern in this paper. Given the BBR congestion control algorithm causes high-packet loss rate and large transmission delay when BBR flows competing for bandwidth resource, a delay response BBR (Delay-BBR) algorithm is proposed for real time video transmission. The main idea is that the sender will actively reduce the rate to let intermediate routers drain the excess occupied buffer once round trip delay signal exceeds a certain threshold. The results show that the delay-BBR can achieve lower transmission delay and lower packet loss rate when compared with QUIC-BBR and WebRTC-BBR. The rate stable feature makes delay-BBR appropriate for real time video transmission. Moreover, a packet scheduling algorithm works in coordination with the rate control algorithm achieves lower frame delivery delay further compared with the benchmark algorithms.

Max-Min Resource Allocation for Video Transmission in NOMA-Based Cognitive Wireless Networks

Non-orthogonal multiple access (NOMA)-based cognitive wireless networks can improve the spectral efficiency to utilize the vacant spectrum resource and exploit the power domain diversity. In this paper, we formulate a max-min resource allocation problem for video traffic in NOMA-based cognitive wireless networks as a mixed integer non-linear programming (MINLP) problem. The max-min video transmission problem is subject to the constraints of maximum accessed user number at each subchannel, total available energy of each secondary user, video encoding characteristics, and interference power threshold. To solve the formulated MINLP problem, we divide it into two subproblems, i.e., a power allocation and secondary user scheduling subproblem, and a video packet scheduling subproblem. First, we apply a successive convex approximation to transform the joint power allocation and secondary user scheduling subproblem into a bi-convex programming problem. Second, the binary search and dual decomposition methods are combined to obtain the approximated optimal power allocation and secondary user scheduling solutions. Finally, we propose a heuristic packet scheduling algorithm. Simulation numerical results show that the proposed algorithm improves the video quality and guarantees the fairness among different secondary users.