Traffic Processing Research Articles

Gigabit UWB video transmission system for wireless video area network

Ultra-wideband (UWB) technology has offered a large application bandwidth which has been reached up to 1 Gb/s recently. One of various UWB specifications, medium access control (MAC) and physical layer (PHY) technologies of WiMedia Alliance can also be used for high speed multimedia applications to establish a wireless video area network (WVAN). In this paper, we propose a Gb/s UWB video transmission system for WVANs. In order to verify the possibilities of Gb/s wireless transmission of multiple video streams, we first built an analysis model and a simulation model. Then we implemented a hardware-based traffic processing block and a Gb/s wireless MAC accelerator. Using the proposed Gb/s video transmission system, we can transmit high definition video streams to several tens of users while guaranteeing quality of service.

모바일 지도 서비스를 위한 공간 객체 포맷의 설계 및 구현

Providing services in a wireless environment with existing wired-based GIS solutions have many limitations such as slow communication, processing rates, and screen size. Among the components, data is considered to be the most important factor in GIS. In this paper, I describe MVF, the most recent technology pioneered by GIS researchers. MVF is a format for efficient usage of spatial object in order to express, save and transform in mobile GIS. First, I describe the definition of MVF syntax, then the implementation of Header Section Generation Module and Main Section Generation Module through the API. Since the issues of network traffic and Hangul processing in mobile GIS are important, I especially consider development of MVF in terms of spatial data size.

Service and Management Oriented Traffic Information Grid

Traffic information service plays an important role in one’s daily life. However, traffic information processing is very complicated because of its dynamic, cooperative and distributed features. This paper presents the Service and Monitoring Oriented Traffic Information Grid. In this system, it is a remarkable characteristic to provide real-time, dynamic information services for travelers and traffic managers by grid technology. The system provides travelers with services of optimized route scheme, bus arrival prediction based on real-time route status, and route status forecast. For traffic managers, the system can provide vehicle tracing, traffic monitoring, history data analysis, and decision making on traffic control strategy. In this regard, key research includes large multi-source traffic data integration, route status forecast, and optimum dynamic travel scheme implementation based on massive GPS data.

The subscription‐cover‐based routeing algorithm in content‐based publish/subscribe

PurposeThe publish/subscribe paradigm is useful for content diffusion in the internet. The purpose of this paper is to propose subscription covering to reduce the size of routeing table and notification matching time.Design/methodology/approachThe paper proposes a necessary and sufficient condition of correct routeing table configuration when using SSCBR algorithm.FindingsExperiments show that both SSCBR and RSCBR can reduce the size of routeing table, network traffic and time.Research limitations/implicationsAll these experiments are based on high speed wireline network. For wireless network, the results may be different.Originality/valueThe paper proposes a necessary and sufficient condition of correct routeing table configuration when using SSCBR algorithm and can easily validate the correctness of brokers' routeing table through it. Because RSCBR calculates less subscription covering relation, its performance in network traffic and average notification processing time may be better than SSCBR in certain scenarios.

Counting bloom filters for pattern matching and anti-evasion at the wire speed

Standard pattern-matching methods used for deep packet inspection and network security can be evaded by means of TCP and IP fragmentation. To detect such attacks, intrusion detection systems must reassemble packets before applying matching algorithms, thus requiring a large amount of memory and time to respond to the threat. In the literature, only a few efforts proposed a method to detect evasion attacks at high speed without reassembly. The aim of this article is to introduce an efficient system for anti-evasion that can be implemented in real devices. It is based on counting bloom filters and exploits their capabilities to quickly update the string set and deal with partial signatures. In this way, the detection of attacks and almost all of the traffic processing is performed in the fast data path, thus improving the scalability of intrusion detection systems.

Delay-Constrained Optimal Data Aggregation in Hierarchical Wireless Sensor Networks

A lot of realistic applications with wireless sensor networks adopt hierarchical architecture in which sensor nodes are grouped into clusters, with each cluster relying on a gateway node for local data aggregation and long-distance radio transmission. Compared to normal sensor nodes, the gateway nodes, also called application nodes (ANs), are equipped with relatively powerful transceivers and have more energy. Nevertheless, since an AN is the main gateway for sensor nodes within its clusters, its energy may be depleted more quickly than normal sensor nodes. As such, it is important to find methods to save energy for ANs. This paper presents a Delay-Constrained Optimal Data Aggregation (DeCODA) framework that considers the unique feature of traffic patterns and information processing at ANs for energy saving. Mathematical models and analytical results are provided, and simulation studies are performed to verify the effectiveness of the DeCODA framework.

Traffic Probe Data Processing for Full-Scale Deployment of Vehicle-Infrastructure Integration

Vehicle-infrastructure integration (VII) is expected to provide greatly improved transportation planning and operations data by enabling many–and eventually all–road vehicles to function as traffic data probes. This means that VII probe data can be processed to produce useful information about the operation of an arterial roadway based on studies using a traffic microsimulation. Simulation provides a “truth model” representation of all vehicle trajectories, which serves as the basis for comparison with probe data sampling strategies under development in the VII program. Modifications to the probe data sampling strategies are suggested to enhance the quality of the data, especially its timeliness. Applications to weather condition detection, incident detection, and realtime adaptive traffic signal control, each with significantly different data requirements, were considered, and the ability of the probe sampling system to support these applications was evaluated. The least-demanding applications, such as weather condition detection, can be served well even at low market penetrations of VII-capable vehicles, but the most demanding applications (real-time adaptive signal control) appear to require the majority of vehicles to be equipped. Recommendations were defined for additional research needed to support the development and deployment of a viable VII traffic probe data system.

DDOS Attack Detecting and Defending Model

This paper presents the APA-ANTI-DDoS (aggregate-based protocol analysis anti-DDoS) model to detect and defend the DDoS attack. APA-ANTI-DDoS model contains the abnormal traffic aggregate module, the protocol analysis module and the traffic processing module. The abnormal traffic aggregate module classifies the network traffic into normal traffic and the abnormal traffic; the protocol analysis module analyzes the potential features of DDoS attack traffic in the abnormal traffic; the traffic processing module filters the abnormal traffic according to the current features of DDoS attack, and resumes the non-attack traffic with the help of testing the congestion control feature of the traffic. The paper then implements the APA-ANTI-DDoS system. The experimental results show that APA-ANTI-DDoS model can primely detect and defend DDoS attack and resume the non-attack traffic at the time of miscarriage of justice to guarantee the legal communication traffic.

VGITS: ITS based on intervehicle communication networks and grid technology

The intelligent traffic system based on intervehicle communication networks and grid technology is proposed. This system adopts hybrid architecture, and diverse real-time traffic services are provided in a centralized or decentralized way. Grid technology is introduced to provide the high performance computing platform for massive traffic data processing and real-time traffic service presenting. Moreover, the computation and communication capacity of the IVC network is developed and exploited to provide decentralized traffic services to drivers. Therefore, the system load is balanced among grid nodes and in-vehicle terminal, and better performance is achieved. At last, a prototype is implemented to demonstrate the efficiency and effectivity.

SIP-based Qos support architecture and session management in a combined IntServ and DiffServ networks

With the development of next-generation convergence networks, the Internet needs to support new network architecture and session management methods that can support various applications requiring differentiated traffic processing and high quality of services, instead of the conventional best-effort service. In next-generation networks based on all-IP, it is expected that SIP will play an important role in session establishment between end-to-end user terminals. Accordingly, this paper proposes a new QoS support SIP-based network architecture that integrates SIP clients, QoS-enabled SIP servers, and policy-based network management in a combined IntServ and DiffServ networks. To control the network access of users and manage network resources, the use of policy servers and QoS extended SIP signaling is presented. Numerical analysis is then used to derive the session establishment delay for the proposed signaling scenarios. Simulations under various environments show appropriate parameter ranges in terms of the server capacity and number of users for the required delay bounds.

Enhanced Internet security by a distributed traffic control service based on traffic ownership

The frequency and intensity of Internet attacks are rising at an alarming pace. Several technologies and concepts were proposed for fighting distributed denial of service (DDoS) attacks: traceback, pushback, i3, SOS and Mayday. This paper shows that in the case of DDoS reflector attacks they are either ineffective or even counterproductive. We then propose the novel concept of traffic ownership and describe a system that extends control over network traffic by network users to the Internet using adaptive traffic processing devices. We safely delegate partial network management capabilities from network operators to network users. All network packets with a source or destination address “owned” by a network user can now also be controlled within the Internet instead of only at the network user's Internet uplink. By limiting the traffic control features and by restricting the realm of control to the “owner” of the traffic, we can rule out misuse of this system. Applications of our system are manifold: prevention of source address spoofing, DDoS attack mitigation, distributed firewall-like filtering, new ways of collecting traffic statistics, service-level agreement validation, traceback, distributed network debugging, support for forensic analyses and many more. A use case illustrates how our system enables network users to prevent and react to DDoS attacks.

A Fair Scheduling Algorithm for Wireless Internet Differentiated Service Networks

The recent Internet needs a network structure and traffic engineering that can support various applications requiring differentiated traffic processing and a high quality of service. The extension of the Internet from wired to wireless systems that generate location-dependent and burst errors has made the support of good services more difficult with existing packet scheduling algorithms. Accordingly, this paper troposes a wireless differentiated service packet scheduling (WDSPS) algorithm that can provide reliable and fair services in differentiated wireless internet service networks. As such, the proposed scheduling algorithm solves the HOL blocking problem within a class packet queue that occurs in a wireless network, supports differentiated services for each class defined in a differentiated service network, and facilitates gradual and efficient service compensation not only among classes but also among flows within a class, thereby preventing a monopoly by one class or one flow. Simulations confirmed that the proposed WDSPS scheduling algorithm could provide the required QoS differentiation between classes and enhanced the service throughput under various wireless network conditions.

Assessing Issues, Technologies, and Data Needs to Meet Traffic Input Requirements by Mechanistic-Empirical Pavement Design Guide: Implementation Initiatives

As part of the implementation initiatives undertaken by the Indiana Department of Transportation Research Division, this paper presents the effort made to identify potential issues arising from traffic data processing and to assess technologies and data needs to meet the requirements of traffic design inputs in the Mechanistic-Empirical Pavement Design Guide. Global Positioning Systems (GPSs) and geographical information system (GIS) technologies were proposed to manage weigh-in-motion (WIM) and automatic vehicle classification site information and manipulate the traffic design input database. Computer programs were developed to process the raw data ASCII files generated from a WIM vendor's software. A platform was developed to combine GPS coordinates, GIS base maps, data processing programs, and the traffic database into an integral unit. Three WIM sites were selected for trial study. It was demonstrated that, with this platform, the WIM sites and database can be accessed visually and more efficiently. I...

Urban Traffic Information Service Application Grid

Traffic information processing is very complicated because of dynamic, cooperative and distributed features. This paper describes the prototype system version 2.0 of Urban Traffic Information Service Application Grid (UTISAG), which is based on the previous version. In this version, a new architecture and more enhanced services are introduced. The remarkable characteristic of the new system is providing dynamic information services for travelers by grid technology. Therefore, the key research includes integrating large multi-source traffic data, forecasting route status, simulating regional traffic flow parallelly, and implementing optimum dynamic travel scheme based on massive GPS data.

고성능 침입탐지 및 대응 시스템의 구현 및 성능 평가

최근 정보통신기반이 급속히 발달하고 사용자가 늘어남에 여러가지 사이버 공격이 늘어나고 있다. 침해사고를 예방하고 효과적인 대응방법이 마련된 침입탐지시스템들은 저속 환경에서의 실시간 분석에 적합하도록 설계되고 구현되었기 때문에, 증가하는 트래픽 양을 처리하는데 어려움이 있다. 또한, 기가비트 이더넷(Gigabit Ethernet) 환경과 같은 고속 네트워크 환경이 현실화되므로 대용량의 데이터를 처리할 수 있는 효과적인 보안 분석 기법들이 필요하다. 본 논문에서는 고속 네트워크 환경에 필요한 침입탐지 및 그 대응 방법에 위한 고속 침입탐지 메커니즘 적용 시스템을 제안한다 이는 패킷 헤더 기반의 패턴 매칭 기능과 시스템 커널 영역에서 수행되는 패킷 데이터 기반의 패턴 매칭 기능을 통해서, 고속 네트워크 환경에 적합한 침입탐지 메커니즘을 제안하며, 시스템의 성능을 기존 운용 시스템과 비교 분석함으로써, 제안한 침입탐지 메커니즘이 트래픽 처리성능면에서 최대 20배까지 우수했다. Recently, the growth of information infrastructure is getting fatter and faster. At the same time, the security accidents are increasing together. We have problem that do not handle traffic because we have the Intrusion Detection Systems in low speed environment. In order to overcome this, we need effective security analysis techniques that ran Processed data of high-capacity because high speed network environment. In this paper we proposed the Gigabit Intrusion Detection System for coordinated security function such as intrusion detection, response on the high speed network. We suggested the detection mechanism in high speed network environment that have pattern matching function based packet header and based packet data that is proceeded in system kernel area, we are shown that this mechanism was excellent until maximum 20 times than existing system in traffic processing performance.

ミクロ交通シミュレーションによる交差点部の安全性評価に関する研究

A traffic safety measure is decided from the results of the traffic accident data. Therefore, it is difficult for us to decide the traffic safety measures and to do the previous evaluation for the traffic safety measures before a traffic accident occurs. In addition to this, we have the problem for implementing the suitable traffic safety measures when the traffic flow changed by modifying the road network and developing the new interchange. To solve this subject, we examined the micro-traffic simulation method (NETSIM and Simr) which is used the verification of traffic processing against the traffic safety evaluation. In consequence, we applied our past research results to the micro-traffic simulation and carried out developing the new safety evaluation technics of intersection.

인터넷 환경에서 서버간 부하 분산을 위한 새로운 웹 클러스터 기법

This paper presents a new web cluster scheme based on dispatcher which does not depend on operating system for server and can examine server`s status interactively. Two principal functions are proposed for new web cluster technique. The one is self-controlled load distribution and the other is transaction fail-safe. Self-controlled load distribution function checks response time and status of servers periodically, then it decides where the traffic goes to guarantee rapid response for every query. Transaction fail-safe function can recover lost queries including broken transaction immediately from server errors. Proposed new web cluster scheme is implemented by C language on Unix operating system and compared with legacy web cluster products. On the comparison with broadcast based web cluster, proposed new web cluster results higher performance as more traffic comes. And on the comparison with a round-robin DNS based web cluster, it results similar performance at the case of traffic processing. But when the situation of one server crashed, proposed web cluster processed traffics more reliably without lost queries. So, new web cluster scheme Proposed on this dissertation can give alternative plan about highly increasing traffics and server load due to heavy traffics to build more reliable and utilized services.

A distributed dynamic channel assignment method for a mixture of narrowband and broadband traffic in a cellular system

This paper proposes an autonomous distributed dynamic channel assignment method, considering a mixture of narrowband and broadband traffic processing in a multicarrier TDMA mobile communication system. As the first step, narrowband and broadband calls are considered, and the system in which the calls share the carrier [carrier-sharing (CS) method], and the system in which the calls use separate carriers [carrier partitioning (CP) method], are compared. For each method, a mathematical model is proposed for the blocking probability analysis in the dynamic channel assignment, based on the steady-state probability. Using the models, the range for which the CS method exhibits a better performance than the CP method is specified. A problem in the dynamic channel assignment in the CS method is that the transmission quality of the broadband call may be degraded by interference from a narrowband call. In order to overcome such a problem, a method is proposed where the suppression of the leftovers of nonavailable channels for assignment, the multicarrier modulation using frequency hopping, the reallocation connection of calls, the variable-rate transmission connection, and the retry-type hand-off are combined. It is verified by computer simulation that the proposed method exhibits a performance which is better than that of the conventional method. © 2000 Scripta Technica, Electron Comm Jpn Pt 1, 83(11): 85–94, 2000

Signal Coordination and Arterial Capacity in Oversaturated Conditions

Models for estimation of the capacities of oversaturated arterials were developed. The input variables in these models are capacities of individual intersections, offsets, and vehicle queue lengths. Models for quantification of capacity loss due to blockage caused by downstream queues are also presented. The proposed models show that when arterial capacity is determined in oversaturated conditions, it is not sufficient to consider only the capacities of critical intersections; instead, the capacities of critical subsystems must be considered. A critical subsystem is any two intersections plus the link that joins them where traffic processing capability is the lowest. This traffic processing capability, or critical subsystem capacity, determines the arterial capacity. It is a function of the capacities of the respective intersections, the offset between them, and the queue length on the link joining them. It is shown that a critical subsystem is not unique in that it may change location over the course of the study period. To minimize capacity loss, it is shown that offsets must be an explicit function of queue lengths. The practical use of the models was demonstrated for an oversaturated two-intersection system. The results show that improper setting of offsets can lead to significant capacity loss. In extreme cases all capacity in a given cycle may be lost if the offsets are not set properly.

Traffic Video Image Processing Systems Installations - An Examination of VIPS Standardization

During two recent research projects (1993-94 and 1996-97), the California Polytechnic State University - San Luis Obispo (Cal Poly) and the California Department of Transportation (Caltrans) conducted field tests in a variety of freeway/highway/street locations and under a variety of conditions to assess the feasibility of deployment of traffic video image processing systems (VIPS) for detection purposes in California. This paper discusses system performance issues as well as some of the major needs for standardization in the area of traffic detection through image processing as observed during the field tests for both freeway monitoring as well as intersection control.