Traffic Policing Research Articles

Estimation of Backlog and Delay in OFDM/ TDMA Systems with Traffic Policing Through Network Calculus

In this paper, we firstly propose a policing algorithm based on multifractal traffic modeling, evaluating its performance in comparison to other algorithms. Further, we present an approach based on Network Calculus for estimating quality of service parameters, such as mean queue length (backlog) and delay. We analyze these two parameters for an OFDM/TDMA based simplified Wimax system with and without the application of traffic modeling based policing algorithms. We also evaluate the performance of the proposed algorithm in policing the traffic in an OFDM / TDMA system.

Obeying the Rules of the Road

Why do people comply with traffic laws and regulations? Road traffic policing tends to be premised on the idea that people comply when they are presented with a credible risk of sanction in the event of non-compliance. Such an instrumental model of compliance contrasts with the normative account offered by procedural justice theory, in which compliance is encouraged by legitimate legal authorities. Comparing these two accounts, we find evidence that both instrumental and normative factors explain variance in motorists’ self-reported propensity to offend. Extending the standard procedural justice account, we also find that it is social identity—not legitimacy—that forms the “bridge” linking procedural fairness and compliance, at least according to a definition of legitimacy that combines felt obligation and moral endorsement. Fair treatment at the hands of police officers seems to enhance identification with the social group the police represent, and in turn, identification seems to motivate adherence to rules (laws) governing social behavior. These findings have implications not only for understandings of legal compliance but also for our understanding of why procedural justice motivates compliance and the role of procedural justice in promoting social cohesion.

TQ/PSO - A New Scheduler to Optimize the Time Frame with PSO in WiMAX Networks

The technological advances of recent years caused a growth in the base of users sharing communication networks, especially with multimedia services such as IPTV, video conferencing and VoIP. These services require more resources and generate a large demand on the infrastructure of the network. Thus, the communication networks for wireless broadband, based on the IEEE 802.16 standard, known as WiMAX, meet the various demands of end users, such as the need for data access at all times and anywhere connectivity and bandwidth large effective. The guarantee of quality of services is a major factor for the performance of communication networks, for this, the scheduling mechanisms, call admission control and traffic policing, should be present. However, the IEEE 802.16 standard only specifies the mechanisms of how these policies should be implemented, but does not define how to implement them. Thus, this article aims to present a new scheduler for traffic uplink, with guaranteed provision of quality services, using the meta-heuristic particle swarm optimization, to calculate the duration of time frame, making possible to find an ideal value, which will provide a better allocation of network users.

Video Activity-Based Traffic Policing: A New Paradigm

The constant development of new multimedia applications, which are “greedy” in terms of bandwidth and Quality of Service (QoS) requirements, calls for new approaches to the traffic policing problem. This paper proposes, analyzes and presents an extensive performance evaluation of such a new approach, namely the activity-based video traffic policing. Using as a motivation recent work, which has shown that the classic traffic policing mechanisms provide unnecessarily strict policing for conforming but bursty video users, we propose five simple and efficient new mechanisms, which take into consideration and exploit video activity and the Group-of Pictures (GoP) pattern of the video traces. Contrary to the classic approach, our mechanisms do not use a token generator based on a fixed rate, but vary the token generation rate according to specific video activity-based algorithms. The results show significant improvement for conforming users, and reveal that dynamic traffic policing can provide much higher efficiency than the widely used static mechanisms. One of the new mechanisms, the Frame Size Aware Token Bucket, is shown to clearly outperform all other policing approaches for conforming users, and to provide comparable policing results with the classic mechanisms for non-conforming video users.

Method of data cleaning for network traffic classification

Network traffic classification aims at identifying the application types of network packets. It is important for Internet service providers (ISPs) to manage bandwidth resources and ensure the quality of service for different network applications. However, most classification techniques using machine learning only focus on high flow accuracy and ignore byte accuracy. The classifier would obtain low classification performance for elephant flows as the imbalance between elephant flows and mice flows on Internet. The elephant flows, however, consume much more bandwidth than mice flows. When the classifier is deployed for traffic policing, the network management system cannot penalize elephant flows and avoid network congestion effectively. This article explores the factors related to low byte accuracy, and secondly, it presents a new traffic classification method to improve byte accuracy at the aid of data cleaning. Experiments are carried out on three groups of real-world traffic datasets, and the method is compared with existing work on the performance of improving byte accuracy. Experiment shows that byte accuracy increased by about 22.31% on average. The method outperforms the existing one in most cases.

Estimation of backlog and delay in OFDM/TDMA systems with traffic policing using Network Calculus

Achieving quality of service (QoS) in OFDM based networks depends, among other factors, on mechanisms for traffic policing or control. Aggregate traffic in high speed networks can present multifractal characteristics such as bursts over a wide range of time scales, heavy tailed inter-arrival time densities, self-similarity and long-range dependence. These properties are followed by a degradation of quality of service for the traffic flows. In this paper, we firstly propose a policing algorithm based on multifractal traffic modeling, evaluating its performance in comparison to other algorithms. We present a more precise in general envelope modeling process in order to efficiently police the input traffic to the system. Further, we present an approach based on Network Calculus for estimating quality of service parameters, such as mean queue length (backlog) and delay. We analyze these two parameters for an OFDM/TDMA based simplified WiMAX system with and without the application of traffic modeling based policing algorithms. In other words, we propose an approach for evaluating some QoS parameters of an OFDM/TDMA system where the traffic is policed. We also evaluate the performance of the proposed algorithm in policing the traffic in an OFDM/TDMA system.

Holistic schedulability analysis for multipacket messages in AFDX networks

The ARINC-664, Part 7 (AFDX) standard defines a communication network based on Ethernet and the UDP/IP protocols. Contrary to general-purpose Ethernet, the timing behavior in AFDX is deterministic due to the use of special network switches and end systems with static routing tables and traffic policing at the sending end through mechanisms called virtual links. Even though the latencies in this network are bounded, there are scheduling and contention effects that need to be analyzed. In this paper we develop a response-time analysis for multipacket messages transmitted through an AFDX network including the scheduling of the virtual links and sub-virtual links, and also the contention in the end systems and in the switches. This analysis allows us to obtain worst-case latencies and output jitter for the network messages with a precise modeling of the sending and receiving ends. These results can be integrated in a holistic approach with the response time analysis of the threads in the processing nodes to obtain end-to-end response times in heterogeneous distributed systems.

Network-Resource Isolation for Virtualization Nodes

One key requirement for achieving network virtualization is resource isolation among slices (virtual networks), that is, to avoid interferences between slices of resources. This paper proposes two methods, per-slice shaping and per-link policing for network-resource isolation (NRI) in terms of bandwidth and delay. These methods use traffic shaping and traffic policing, which are widely-used traffic control methods for guaranteeing QoS. Per-slice shaping utilizes weighted fair queuing (WFQ) usually applied to a finegrained flow such as a flow from a specific server application to a user. Since the WFQ for fine-grained flows requires many queues, it may not scale to a large number of slices with a large number of virtual nodes. Considering that the purpose of NRI is not thoroughly guaranteeing QoS but avoiding interferences between slices, we believe per-slice shaping suffices our objective. In contrast, per-link policing uses traffic policing per virtual link. It requires less resource and achieves less strict isolation between hundreds of slices. Our results show that both methods perform NRI well but the performance of the former is better in terms of delay. Accordingly, per-slice shaping is effective for delay-sensitive services while per-link policing may be sufficiently used for the other types of services.

Service Violation Monitoring Model for Detecting and Tracing Bandwidth Abuse

Bandwidth abuse is a critical Internet service violation. However, its origins are difficult to detect and trace given similarities between abusive and normal traffic. So far, there is no capable and scalable mechanism to deal with bandwidth abuse. This paper proposes a distributed edge-to-edge model for monitoring service level agreement (SLA) violations and tracing abusive traffic to its origins. The mechanism of policing misbehaving user traffic at a single random early detection (RED) gateway is used in the distributed monitoring of SLA violations, including violations carried out through several gateways. Each RED gateway reports misbehaving users who have been sent notifications of traffic policing to an SLA monitoring unit. Misbehaving users are considered suspicious users and their consumed bandwidth shares are aggregated at every gateway to be compared with SLA-specified ratios. Bandwidth is abused when SLA-specified ratios are exceeded. By reporting bandwidth abuse, illegitimate users can be isolated from legitimate ones and source hosts of abusive traffic may be traced. Approximate simulation results show that the proposed model can detect any SLA violation and identify abusive users. In addition, the proposed model can trace user violations back to their source machines in real time.

One Method of Cloud Computing Bandwidth Allocation Based on Fairness

In order to solve the bandwidth allocation unfairness problem in the cloud computing network, one method uses fairness congestion control algorithm, access control list (ACL) and traffic policing and traffic shaping in the paper. The method can rationally solve the problem after analyzing the reason of cloud computing bandwidth allocation unfairness. For illustration, one network video conference example was utilized to show the method in solving bandwidth allocation unfairness problem.The experimental results show network bandwidths are fairly allocated, packet loss ratio and latency is obvious improvement. The method deals with non-adaptive UDP and TCP adaptive flow congestion and provides the end-to-end quality of service over the differentiated services networks, and the bandwidth allocation problem based on fairness in the cloud computing network is solved well. DOI: http://dx.doi.org/10.11591/telkomnika.v11i2.2059 Full Text: PDF

Design and Analysis of AFDX Network Based High-Speed Avionics System of Civil Aircraft

Avionics Full Duplex Switched Ethernet (AFDX) standardized as ARINC 664 is a major upgrade for integrated avionics systems of civil aircraft. It becomes the current communication technology in the context of avionics and provides a backbone network for the civil avionics system. This paper focuses on features of AFDX network protocol. Architecture of AFDX switch based on shared memory is proposed to meet the requirements of avionics real-time system. In addition, frame filtering, traffic policing and frame schedule function are used to eliminate uncertainties in huge traffic flows. End System (ES) host-target architecture is also researched in this paper. Virtual link scheduler, redundancy management, and protocol stack in ES are designed to ensure determinism and reliability of data communication. AFDX switch and ES have been successfully developed, and configuration tool, ARINC 615A loader and simulation tool related to AFDX network are also provided as package solution to support avionics system construction. Finally, AFDX switch and ESes have passed ARINC 664 protocol conformance test and certification, the test results show that our AFDX products meet the requirements of real-time communication, determinism and reliability defined in ARINC 664

Loss probability estimation and control for OFDM/TDMA wireless systems considering multifractal traffic characteristics

In this paper, we analyze the queueing performance in terms of loss rate of an OFDM (orthogonal frequency-division multiplexing)/TDMA (time division multiplexing access) based wireless system taking into account the multifractal behavior of the wireless traffic flows. To this end, first, we show evidences of multifractal characteristics on wireless traffic traces. These findings motivated us to propose a traffic policing and control scheme based on a multifractal envelope process in order to maintain the traffic flows well-behaved, i.e., in accordance to the desired QoS parameters. Furthermore, by assuming a multifractal traffic model, we derive a data loss probability equation for wireless traffic flows that was applied to the OFDM/TDMA based wireless system. Simulations and comparisons to other methods were carried out in order to verify the efficiency of the proposed traffic policing scheme as well as of the loss probability estimation approach.

Traffic management based on token bucket mechanism for WiMAX networks

In large scale networks like the IEEE 802.16 (WiMAX), it is very important not only to monitor, but also to control the amount of traffic injected into the network. This process helps in decreasing congestion and by consequence, in guaranteeing the Quality of Service (QoS) requirements for each class of traffic. In this study we propose a traffic policer based on token bucket concept for WiMAX networks. Token bucket parameters (token rate and bucket size) are adjusted according to the traffic characteristics for each traffic class individually. Simulation results show that the proposed traffic policing technique greatly enhances the network performance. It decreases the average delay for real time traffic like rtPS, and therefore, reduces data drop probability due to missed deadlines. It also decreases data loss probability for non real time service class like nrtPS.

The effects of increased police enforcement along a route in London

There have been many studies of the link between the level of policing in an area and the behaviour of local drivers, but those that have been conducted in the United Kingdom were either small scale or were conducted many years ago. Consequently, a practical trial was carried out in London in May 2008 to investigate the effects of increasing the level of traffic policing in a busy urban area under modern conditions. Operation Radar ran for four weeks and increased the visible presence of police on a six mile stretch of the A23 in South London. Two teams of six officers and one sergeant were deployed in two shifts per weekday on the six mile route, using both static and mobile policing methods in a mixture of vehicles.This paper summarises the effects achieved, both in terms of the number of offences detected by the police and the effects on driver behaviour observed by a series of roadside surveys. These surveys measured vehicle speeds and drivers’ use of mobile phones and seatbelts. Vehicle speeds reduced systematically during the operation along the route and in surrounding areas, and some effects remained at least two weeks after the operation had finished. The survey data do not, however, show any positive effect of enforcement on the use of mobile phones or seatbelts.

Performance Improvement of video based applications in WFQ using Committed Access Rate

ABSTRACT In this paper, the video received, IP drop in WFQ is improved using committed access rate (CAR). The committed access rate is used for video and http applications and for WFQ queuing scheme. From results, it has been analyzed that the video received in WFQ shows much better improvement than the conventional. The significant results have been investigated for IP drop in case of WFQ with committed access rate and conventional which are 0.7 and 8.36 packets per second respectively. The result for video received in case of WFQ with committed access rate and conventional is 383.8 and 5.56 packets per seconds. Keywords Weighted Fair Queue, Committed Access Rate (CAR), IP QoS, ToS 1. INTRODUCTION Committed access rate is a method for managing unwanted traffic on the network without affecting the important traffic. CAR set high TOS for video traffic and low TOS for HTTP traffic. WFQ can prioritize the traffic and give the high bandwidth to the video traffic. CAR provides high bandwidth for video applications. CAR defines a rate-limiting feature for policing traffic, which helps managing the network's access bandwidth policy by ensuring that traffic falling within specified rate parameters is transmitted, while dropping packets that exceed the acceptable amount of traffic or transmitting them with a different priority. The input and output traffic on an interface or sub-interface may be selected based on a flexible set of criteria like all IP traffic or all traffic on an interface or based on IP precedence or MAC address or IP Access List, after which it applies the contracted rate limits, which are the parameters for a token bucket algorithm i.e. average rate, normal burst size and excess burst size. Once the packet is determined to be conforming or exceeding its limits the defined conform/ exceed action will be taken. Committed access rate can be used with the IP traffic. It doesn’t work for non-IP traffic like AppleTalk, IPX, SNA, DECNet [1]. CAR is a limiting or policing scheme which consists of certain rules based on attributes such as class of service (COS), data rate, normal burst size and excess burst size which sets a bandwidth limit for specific types of traffic on router interfaces. For example, you can create a policy that limits web traffic to 200 kilobits/sec. This puts a cap on the bandwidth available to that traffic, ensuring that the remainder of the interface’s bandwidth is available to other kinds of traffic. In this example, if web traffic does not fill 200 kilobits/sec, other kinds of traffic can use the unused bandwidth. Packets are dropped if traffic bursts exceed the limit. CAR limiting does not attempt to smooth or shape the traffic flow in the way that GTS or FRTS attempt to do. Because CAR does not buffer the traffic, there is no delay in sending it, unless the traffic flow exceeds your rate policy and it is dropped. One of the main uses for limiting policies is to ensure that traffic coming into the network is not exceeding agreed-upon rates. If the limiting policy for inbound traffic is defined, the traffic can be controlled before it gets into your network at the inbound interface [2]. Traffic policing controls the maximum rate of traffic sent or received on an interface. Based on the results of the token bucket measurement, an action can be configured to mark packets and separate packets into multiple classes or levels of service. Traffic polices provide two key benefits: Bandwidth management through rate limiting: It control the maximum rate of traffic sent or received on an interface. Traffic that falls within the rate parameters is sent, whereas traffic that exceeds the parameters is dropped, or sent with a different priority. Packet marking through IP precedence, QoS group, or DSCP value setting

POPI: A User-Level Tool for Inferring Router Packet Forwarding Priority

Packet forwarding prioritization (PFP) in routers is one of the mechanisms commonly available to network operators. PFP can have a significant impact on the accuracy of network measurements, the performance of applications and the effectiveness of network troubleshooting procedures. Despite its potential impacts, no information on PFP settings is readily available to end users. In this paper, we present an end-to-end approach for PFP inference and its associated tool, POPI. This is the first attempt to infer router packet forwarding priority through end-to-end measurement. POPI enables users to discover such network policies through measurements of packet losses of different packet types. We evaluated our approach via statistical analysis, simulation and wide-area experimentation in PlanetLab. We employed POPI to analyze 156 paths among 162 PlanetLab sites. POPI flagged 15 paths with multiple priorities, 13 of which were further validated through hop-by-hop loss rates measurements. In addition, we surveyed all related network operators and received responses for about half of them all confirming our inferences. Besides, we compared POPI with the inference mechanisms through other metrics such as packet reordering [called out-of-order (OOO)]. OOO is unable to find many priority paths such as those implemented via traffic policing. On the other hand, interestingly, we found it can detect existence of the mechanisms which induce delay differences among packet types such as slow processing path in the router and port-based load sharing.

Dynamic versus Static Traffic Policing: A New Approach for Videoconference Traffic over Wireless Cellular Networks

The subject of traffic policing for computer communication networks has been studied extensively in the literature. However, the constant development of new multimedia applications which are ldquogreedyrdquo in terms of bandwidth and Quality of Service requirements calls for new approaches to the traffic policing problem. In this work, we introduce a new video model for single H.263 videoconference sources and we use it in order to propose a new traffic policing approach for wireless videoconference traffic. We study well-known traffic policing mechanisms which still present interesting, unsolved problems when servicing video traffic and propose, to the best of our knowledge, for the first time in the relevant literature that the token generator is based on a traffic model and not on a fixed rate. The proposed approach shows significant improvement in the results obtained by all the traffic policing mechanisms, and hence, shows that dynamic traffic policing can provide much higher efficiency than the widely used static approach.

Spanning tree elevation protocol: Enhancing metro Ethernet performance and QoS

The economics and familiarity of Ethernet technology is motivating the vision of wide-scale adoption of Metro Ethernet Networks (MEN). Despite the progress made by the community on additional Ethernet standardization and commercialization of the first generation of MEN, the fundamental technology does not meet the expectations that carriers have traditionally held in terms of network resiliency, load management, and Quality of Service (QoS). We propose a new concept of Spanning Tree Elevation Protocol (STEP) that increases MEN performance while supporting QoS including traffic policing and service differentiation. STEP manages multiple Spanning Trees as a means to control the traffic flow rates and to differentiate classes of traffic. Whenever a service level agreement is compromised, STEP redirects frames of affected flows to the next spanning tree in sequence utilizing the alternate paths. As a result, the capacity in terms of network throughput is greatly enhanced while almost avoiding any reconvergence time in the case of failures. The gain ranges from 1.7% to 7.3% of the total traffic in the face of failure; while load balancing increases an additional 12.8% to 37% of the total throughput. At the same time, STEP maintains the required bandwidth for high priority traffic class during the failure scenarios and the high congestion scenarios.

Does Policing the Risk Society Hold the Road Risk?

Road risk consumes a great deal of police effort. It is currently estimated that in OECD countries, some 10 to 20 percent of police manpower resources go into policing the roads. Ericson and Haggerty's book, Policing the Risk Society (1997), sets out to annul Bittner's classical, coercion-based reading of the police and replace it with a radically new paradigm that foregrounds the panoptical or knowledge work dimension of the police and its potential to serve the interests of non-police social-disciplinary institutions. In this article, we test this neo-Foucauldian paradigm on the basis of a body of research into road traffic policing. As a result, we observe that though non-police owner-managers of new risks challenge the societal immanence, centrality and publicness of police organizations, with time, these challenges fail. We therefore argue that Ericson and Haggerty's notion of panoptical policing should be taken as a theoretical innovation, which, far from eliminating Bittner's paradigm, enhances it with a new force.

An ethernet switch architecture for bandwidth provision of broadband access networks

Ethernet is one of the potential candidates capable of meeting the bandwidth demands of subscribers and successfully supporting various services in broadband access networks. However, the lack of a traffic management capability is a major obstacle to successful deployment. In this article we suggest an Ethernet switch architecture that offers performance-guaranteed broadband access services. We also discuss the micro-architecture of the switch and associated design issues. Switches in the proposed architecture identify subscriber traffic without handling higher layer protocols, regulate it with per subscriber traffic policing, and ensure deterministic network performance. The implemented switch ASIC offers 28 gigabit Ethernet ports, integrating 9 million logic gates and 51 memories holding a total of 3.4 Mb to store data and control states on a single 10 mm x 10 mm die using 0.13 mum CMOS technology. The performance evaluation results, verified using a network performance analyzer, show that the proposed architecture guarantees transfer rates of individual subscribers based on their service agreements, effectively protecting network resources from excess traffic, which adversely affects the QoS of existing users' traffic.