This paper evaluates the performance of the IEEE 802.11p standard for vehicular communication networks. The authors analyze the architecture of the Wireless Access in Vehicular Environments (WAVE) system and the IEEE 802.11p standard. They implement the key parameters of 802.11p in the ns-2 network simulator and use a realistic vehicular mobility model from VanetMobiSim. The performance metrics of throughput, end-to-end delay, and packet loss ratio are analyzed for a scenario of vehicles on a highway, with an ambulance transmitting periodic safety messages. The results show that vehicles can receive broadcast messages when within 138 meters of the ambulance, with little packet loss and similar throughput between vehicles
Class lecture by Prof. Raj Jain on Carrier Ethernet. The talk covers Options to Connect Two Data Centers?, Plesiochronous Digital Hierarchy (PDH), SONET/SDH, Multiprotocol Label Switching (MPLS), Label Switching Example, IP over MPLS over Ethernet, Martini Draft, Pseudo Wire: L2 Circuits over IP, Ethernet over PWE3 over MPLS, Virtual Private LAN Service (VPLS), Differentiated Services, Carriers vs. Enterprise, Issue: UNI vs Peer-to-Peer Signaling, UNI vs. ENNI, Operator Virtual Connection (OVC), Metro Access Ethernet Private Line, End-to-End Metro Ethernet Connection, Ethernet Virtual Connections (EVCs), Metro Ethernet Service Attributes, Metro Ethernet OAM, Metro Ethernet OAM Messages, Metro Ethernet Use Cases, Ethernet Provider Bridge (PB), Provider Backbone Network (PBB), MAC-in-MAC Frame Format, PBB Service Instance, Connection Oriented Ethernet, VLAN Cross-Connect, PBB-TE, PBB-TE QoS, Ethernet Tagged Frame Format Evolution, Comparison of Technologies. Video recording available in YouTube.
A presentation given by RAD’s CTO, Dr. Yaakov Stein, at the 2012 MPLS and Ethernet World Congress. The presentation compares the two technologies in ten critical categories and grades them on suitability, coverage and maturity
In this presentation, RAD’s Chief Scientist, Dr. Yaakov Stein, reviews the evolution of Ethernet OAM tools and practices and discusses the drivers for their developm
The NGN Carrier Ethernet System: Technologies, Architecture and Deployment Mo...Cisco Canada
This presentation discusses market trends and its impact on Network infrastructure, Cisco carrier Ethernet Transport Architecture, Cisco carrier Ethernet portfolio and TCO Leadership.
As SDH/SONET networks are being phased out, power utilities are starting to migrate to future-proof packet networks. This presentation reviews and compares Carrier Ethernet, MPLS and MPLS-TP to help power utilities determine which alternative offers the best fit for the operational needs of their mission-critical applications.
This presentation reviews the various tools that carrier-grade Ethernet offers to meet the performance required from the ICT network and discusses strategies for the transition to Smart Grid communications
Class lecture by Prof. Raj Jain on Carrier Ethernet. The talk covers Options to Connect Two Data Centers?, Plesiochronous Digital Hierarchy (PDH), SONET/SDH, Multiprotocol Label Switching (MPLS), Label Switching Example, IP over MPLS over Ethernet, Martini Draft, Pseudo Wire: L2 Circuits over IP, Ethernet over PWE3 over MPLS, Virtual Private LAN Service (VPLS), Differentiated Services, Carriers vs. Enterprise, Issue: UNI vs Peer-to-Peer Signaling, UNI vs. ENNI, Operator Virtual Connection (OVC), Metro Access Ethernet Private Line, End-to-End Metro Ethernet Connection, Ethernet Virtual Connections (EVCs), Metro Ethernet Service Attributes, Metro Ethernet OAM, Metro Ethernet OAM Messages, Metro Ethernet Use Cases, Ethernet Provider Bridge (PB), Provider Backbone Network (PBB), MAC-in-MAC Frame Format, PBB Service Instance, Connection Oriented Ethernet, VLAN Cross-Connect, PBB-TE, PBB-TE QoS, Ethernet Tagged Frame Format Evolution, Comparison of Technologies. Video recording available in YouTube.
A presentation given by RAD’s CTO, Dr. Yaakov Stein, at the 2012 MPLS and Ethernet World Congress. The presentation compares the two technologies in ten critical categories and grades them on suitability, coverage and maturity
In this presentation, RAD’s Chief Scientist, Dr. Yaakov Stein, reviews the evolution of Ethernet OAM tools and practices and discusses the drivers for their developm
The NGN Carrier Ethernet System: Technologies, Architecture and Deployment Mo...Cisco Canada
This presentation discusses market trends and its impact on Network infrastructure, Cisco carrier Ethernet Transport Architecture, Cisco carrier Ethernet portfolio and TCO Leadership.
As SDH/SONET networks are being phased out, power utilities are starting to migrate to future-proof packet networks. This presentation reviews and compares Carrier Ethernet, MPLS and MPLS-TP to help power utilities determine which alternative offers the best fit for the operational needs of their mission-critical applications.
This presentation reviews the various tools that carrier-grade Ethernet offers to meet the performance required from the ICT network and discusses strategies for the transition to Smart Grid communications
CyberLab Training Division :
The .NET Framework is Microsoft's Managed Code programming model for building applications on Windows clients, servers, and mobile or embedded devices. Microsoft's .NET Framework is a software technology that is available with several Microsoft Windows operating systems. In the following sections describes , the basics of Microsoft .Net Frame work Technology and its related programming models.
What is Microsoft .Net Framework
what are the functions of microsoft .net framework?
Common Language Runtime in .Net Framework
How to Common Language Runtime
What is .Net Framework Class Library
What is Common Language Specification
What is Common Type System
What is Microsoft Intermediate Language
What is Portable Executable (PE) File Format
What is Microsoft Just In Time Compiler
How to Managed Code - Microsoft .Net Framework
What is .Net Framework Metadata
what is .Net Framework Assembly
What is Assembly Manifest
What is Global Assembly Cache
What is a .Net Satellite Assembly?
What are the contents of an Assembly?
How to Private Assembly and Shared Assembly
What is Microsoft .Net Strong Name
What is .Net Namespaces
What is Application Domain
What is Code Access Security
What is Garbage Collection
.Net Threads
For More Details.
Visit: http://www.cyberlabzone.com
CyberLab Training Division :
The .NET Framework is Microsoft's Managed Code programming model for building applications on Windows clients, servers, and mobile or embedded devices. Microsoft's .NET Framework is a software technology that is available with several Microsoft Windows operating systems. In the following sections describes , the basics of Microsoft .Net Frame work Technology and its related programming models.
What is Microsoft .Net Framework
what are the functions of microsoft .net framework?
Common Language Runtime in .Net Framework
How to Common Language Runtime
What is .Net Framework Class Library
What is Common Language Specification
What is Common Type System
What is Microsoft Intermediate Language
What is Portable Executable (PE) File Format
What is Microsoft Just In Time Compiler
How to Managed Code - Microsoft .Net Framework
What is .Net Framework Metadata
what is .Net Framework Assembly
What is Assembly Manifest
What is Global Assembly Cache
What is a .Net Satellite Assembly?
What are the contents of an Assembly?
How to Private Assembly and Shared Assembly
What is Microsoft .Net Strong Name
What is .Net Namespaces
What is Application Domain
What is Code Access Security
What is Garbage Collection
.Net Threads
For More Details.
Visit: http://www.cyberlabzone.com
CyberLab Training Division :
The .NET Framework is Microsoft's Managed Code programming model for building applications on Windows clients, servers, and mobile or embedded devices. Microsoft's .NET Framework is a software technology that is available with several Microsoft Windows operating systems. In the following sections describes , the basics of Microsoft .Net Frame work Technology and its related programming models.
What is Microsoft .Net Framework
what are the functions of microsoft .net framework?
Common Language Runtime in .Net Framework
How to Common Language Runtime
What is .Net Framework Class Library
What is Common Language Specification
What is Common Type System
What is Microsoft Intermediate Language
What is Portable Executable (PE) File Format
What is Microsoft Just In Time Compiler
How to Managed Code - Microsoft .Net Framework
What is .Net Framework Metadata
what is .Net Framework Assembly
What is Assembly Manifest
What is Global Assembly Cache
What is a .Net Satellite Assembly?
What are the contents of an Assembly?
How to Private Assembly and Shared Assembly
What is Microsoft .Net Strong Name
What is .Net Namespaces
What is Application Domain
What is Code Access Security
What is Garbage Collection
.Net Threads
For More Details.
Visit: http://www.cyberlabzone.com
Energy resources, energy conversion processes, and reliable energy delivery are the important issues in the 21st century. Smart grid is an intelligent electricity network aimed at providing interoperability between seven different domains: generation, transmission, distribution, customer, operations, markets, and service provider. This new approach is achieved by integration of power systems, advanced communications and information technology. In this paper, the technologies required for the smart will be studied. Different communication technologies, protocols and standards required for various component of smart grid will be identified.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
INVESTIGATION AND EVALUATION OF IEEE 802.11N WLANS LINK FEATURES PERFORMANCE ...pijans
For an efficient design of wireless local-area networks (WLANs), the simulation tools are important to accurately estimate the IEEE 802.11n/ac link features for WLANs. However, this true simulation of network behavior is critical in designing high-performance WLANs. Through testing, analysis, and modeling of the proposed scheme repetitively, the design of the WLAN can be enhanced with a small budget before making its practical implementation. Many network simulation tools have been established to give solutions for this request and ns-3 is the most widely used tools among them by the research industry as an open-source network simulator. In this paper, we examine the various link features of the 802.11n WLANs under several conditions. We investigate the effects of 802.11n WLAN modulation and coding schemes (MCSs), 20MHz single channel or 40 MHz bonded channel, guard intervals (GI), frame aggregation, data encoding, number of antennas and their data rate, and link distance features of 802.11n WLAN in ns-3 when only a unique host connects with the access point (AP) and generates data traffic. Besides, the performance for an enterprise scenario proposed by the IEEE 802.11ax study group is evaluated when several hosts are simultaneously creating traffic with their associated APs. The results demonstrate that ns-3 support most of the link features of the 802.11n protocol with significant accuracy.
Investigation and Evaluation of IEEE 802.11n WLANs Link Features Performance ...pijans
For an efficient design of wireless local-area networks (WLANs), the simulation tools are important to accurately estimate the IEEE 802.11n/ac link features for WLANs. However, this true simulation of network behavior is critical in designing high-performance WLANs. Through testing, analysis, and modeling of the proposed scheme repetitively, the design of the WLAN can be enhanced with a small budget before making its practical implementation. Many network simulation tools have been stablished to give solutions for this request and ns-3 is the most widely used tools among them by the research industry as an open-source network simulator. In this paper, we examine the various link features of the 802.11n WLANs under several conditions. We investigate the effects of 802.11n WLAN modulation and coding schemes (MCSs), 20MHz single channel or 40 MHz bonded channel, guard intervals (GI), frame aggregation, data encoding, number of antennas and their data rate, and link distance features of 802.11n WLAN in ns-3 when only a unique host connects with the access point (AP) and generates data traffic. Besides, the performance for an enterprise scenario proposed by the IEEE 802.11ax study group is evaluated when several hosts are simultaneously creating traffic with their associated APs. The results demonstrate that ns-3 support most of the link features of the 802.11n protocol with significant accuracy
Investigation and Evaluation of IEEE 802.11n Wlans Link Features Performance ...pijans
For an efficient design of wireless local-area networks (WLANs), the simulation tools are important to accurately estimate the IEEE 802.11n/ac link features for WLANs. However, this true simulation of network behavior is critical in designing high-performance WLANs. Through testing, analysis, and modeling of the proposed scheme repetitively, the design of the WLAN can be enhanced with a small budget before making its practical implementation. Many network simulation tools have been established to give solutions for this request and ns-3 is the most widely used tools among them by the research industry as an open-source network simulator. In this paper, we examine the various link features of the 802.11n WLANs under several conditions. We investigate the effects of 802.11n WLAN modulation and coding schemes (MCSs), 20MHz single channel or 40 MHz bonded channel, guard intervals (GI), frame aggregation, data encoding, number of antennas and their data rate, and link distance features of 802.11n WLAN in ns-3 when only a unique host connects with the access point (AP) and generates data traffic. Besides, the performance for an enterprise scenario proposed by the IEEE 802.11ax study group is evaluated when several hosts are simultaneously creating traffic with their associated APs. The results demonstrate that ns-3 support most of the link features of the 802.11n protocol with significant accuracy.
SPEECH QUALITY EVALUATION BASED CODEC FOR VOIP OVER 802.11P ijwmn
Voice over Internet Protocol (VoIP) may provide good services through Vehicular ad hoc networks
(VANETs) platform by providing services to many application scenarios range from safety to comfort.
However, VANETs networks introduce many challenges for supporting voice with QoS requirements. In
this paper, our study is based on Inter-Vehicle voice streaming rely on multi-hop fashion. For this task, a
performance evaluation of various audio CODECs will be analyzed by mean of simulations.
Furthermore, we test the impact of network environment on QoS metrics. To achieve good results,
CODECs behaviour is tested by using mobility information obtained from vehicular traffic generator. The
mobility model is based on the real road maps of an urban environment. Focusing on inter-vehicular
voice traffic quality, we provide simulations results in terms of both user level (MOS) metrics and
network level (such as Losses). According to this performance evaluation, we show that G.723.1 CODEC
worked well in the urban VANET environment.
VANET is a decentralized network that allows the vehicles to communicate with each other for providingsafety warning, traffic management and driver assistance systems. Vehicular IP in Wireless Access in Vehicular Environments (VIP-WAVE)has characterized the IP configuration for extended andnon-extended IP services, and amobilitymanagement scheme supportedby Proxy Mobile IPv6 over WAVE.As the vehicular networks are formed even in remote areas with inadequate power source, the units have power constraints which are overcome by power control in the proposed system .The objective of the paper is to improve the quality of the network by providing internet accesswith transmit power control along which the distance between the RSU and on-board vehicular units(OBU)is determined i.e., power consumption is reduced when at least distance. Hence the RSU provides Distance Cautious Internet Protocol (DCIP) to the OBU for internet access.This paper analyses the WAVE standard and its support of IP based applications, and proposesDistance Cautious Internet Protocol in WAVE(DCIP-WAVE).
An Accurate Performance Analysis of Hybrid Efficient and Reliable MAC Protoco...IJECEIAES
Vehicular Ad Hoc Networks (VANETs) is a technology supporting two types of applications, safety and service applications with higher and lower priorities respectively. Thereby, Medium Access Control (MAC) protocol is designed to provide reliable and efficient data broadcasting based on prioritization. Different from the IEEE 1609.4 (legacy), HER-MAC protocol is a new multi-channel MAC proposed for VANETs, offering remarkable performance with regards to safety applications transmission. This paper focuses on the analysis of packet delivery ratio of the HER-MAC protocol under non-saturated conditions. 1-D and 2-D Markov chains have been developed for safety and non-safety applications respectively, to evaluate mathematically the performance of HER-MAC protocol. The presented work has taken into account the freezing of the backoff timer for both applications and the backoff stages along with short retry limit for non-safety applications in order to meet the IEEE 802.11p specifications. It highlights that taking these elements into consideration are important in modeling the system, to provide an accurate estimation of the channel access, and guarantees that no packet is served indefinitely. More precise results of the system packet delivery ratio have been yield. The probability of successful transmission and collisions were derived and used to compute the packet delivery ratio. The simulation results validate the analytical results of our models and indicate that the performance of our models outperformed the existing models in terms of the packet delivery ratio under different number of vehicles and contention window.
Impact of Randomness on MAC Layer Schedulers over High Speed Wireless Campus ...ijcsse
IEEE802.11e standard provides an EDCA mechanism to ensure the QoS using service differentiation function for IMM traffics through the WCN. In an EDCA mechanism, IMM traffics have been classified into four categories and each category has specific priority. Many EDCA schedulers allow these traffics to access the channel based on assigned priorities. The IMM high priority traffic is high delay sensitive and required high bandwidth to ensure QoS over the networks. Scheduling mechanism is the effective way to satisfy IMM traffic but it cannot give guarantee because of the randomness of some EDCA schedulers or proposed networks. In order to provide the QoS, scheduling mechanism is the challenging issue to transmit IMM traffic through the channel and it is still need to be solved over WCN. This work aims to examine the effect of the randomness on different MAC layer schedulers' performance and evaluates the performance of the proposed schedulers using different performance metrics in WCN.
Wireless Evolution: IEEE 802.11N, 802.11AC, and 802.11AX Performance Comparisonpijans
The widespread adoption of IEEE 802.11 WLANs is attributed to their inherent mobility, flexibility, and
cost-effectiveness. Within the IEEE 802 working group, a dedicated task group is diligently advancing
WLAN technologies, particularly tailored for dense network scenarios. Amidst these advancements, the
802.11ac protocols have emerged as a preferred choice, delivering superior data transfer rates compared
to the preceding 802.11n standard. Significantly, the sixth-generation wireless protocol, IEEE 802.11ax,
has been introduced, showcasing enhanced performance capabilities that outpace its fifth-generation
predecessor, 802.11ac.In this pioneering investigation, we engage in an in-depth simulation-based scrutiny
of prominentWLAN protocols—namely, IEEE 802.11n, IEEE 802.11ac, and the cutting-edge IEEE
802.11ax. Our exhaustive analyses traverse a spectrum of critical metrics, encompassing throughput,
coverage, spectral efficiency, Tx/Rx gain, and Tx/Rx power.In a single-user and SISO scenario, both
802.11ac and 802.11ax outperform 802.11n. Significantly, 802.11ax surpasses the previous 802.11n/ac
standards, highlighting substantial advancements in wireless performance.
Similar to Performance evaluation-of-ieee-802.11p-for-vehicular-communication-networks (20)
Analyze the Customer Requirements
Characterize the Existing Network and Sites
Design the Network Topology and Solutions
Design a Network Topology
Design a Model for Network Layer Addressing and Naming
Select the Switching and Routing Protocols
Network Security Design
Network Management Design
Optimize the Network Design
Select Technologies and Devices
Test the Network Design
Document the Network Design
Transcript: Selling digital books in 2024: Insights from industry leaders - T...BookNet Canada
The publishing industry has been selling digital audiobooks and ebooks for over a decade and has found its groove. What’s changed? What has stayed the same? Where do we go from here? Join a group of leading sales peers from across the industry for a conversation about the lessons learned since the popularization of digital books, best practices, digital book supply chain management, and more.
Link to video recording: https://bnctechforum.ca/sessions/selling-digital-books-in-2024-insights-from-industry-leaders/
Presented by BookNet Canada on May 28, 2024, with support from the Department of Canadian Heritage.
Builder.ai Founder Sachin Dev Duggal's Strategic Approach to Create an Innova...Ramesh Iyer
In today's fast-changing business world, Companies that adapt and embrace new ideas often need help to keep up with the competition. However, fostering a culture of innovation takes much work. It takes vision, leadership and willingness to take risks in the right proportion. Sachin Dev Duggal, co-founder of Builder.ai, has perfected the art of this balance, creating a company culture where creativity and growth are nurtured at each stage.
Essentials of Automations: Optimizing FME Workflows with ParametersSafe Software
Are you looking to streamline your workflows and boost your projects’ efficiency? Do you find yourself searching for ways to add flexibility and control over your FME workflows? If so, you’re in the right place.
Join us for an insightful dive into the world of FME parameters, a critical element in optimizing workflow efficiency. This webinar marks the beginning of our three-part “Essentials of Automation” series. This first webinar is designed to equip you with the knowledge and skills to utilize parameters effectively: enhancing the flexibility, maintainability, and user control of your FME projects.
Here’s what you’ll gain:
- Essentials of FME Parameters: Understand the pivotal role of parameters, including Reader/Writer, Transformer, User, and FME Flow categories. Discover how they are the key to unlocking automation and optimization within your workflows.
- Practical Applications in FME Form: Delve into key user parameter types including choice, connections, and file URLs. Allow users to control how a workflow runs, making your workflows more reusable. Learn to import values and deliver the best user experience for your workflows while enhancing accuracy.
- Optimization Strategies in FME Flow: Explore the creation and strategic deployment of parameters in FME Flow, including the use of deployment and geometry parameters, to maximize workflow efficiency.
- Pro Tips for Success: Gain insights on parameterizing connections and leveraging new features like Conditional Visibility for clarity and simplicity.
We’ll wrap up with a glimpse into future webinars, followed by a Q&A session to address your specific questions surrounding this topic.
Don’t miss this opportunity to elevate your FME expertise and drive your projects to new heights of efficiency.
Epistemic Interaction - tuning interfaces to provide information for AI supportAlan Dix
Paper presented at SYNERGY workshop at AVI 2024, Genoa, Italy. 3rd June 2024
https://alandix.com/academic/papers/synergy2024-epistemic/
As machine learning integrates deeper into human-computer interactions, the concept of epistemic interaction emerges, aiming to refine these interactions to enhance system adaptability. This approach encourages minor, intentional adjustments in user behaviour to enrich the data available for system learning. This paper introduces epistemic interaction within the context of human-system communication, illustrating how deliberate interaction design can improve system understanding and adaptation. Through concrete examples, we demonstrate the potential of epistemic interaction to significantly advance human-computer interaction by leveraging intuitive human communication strategies to inform system design and functionality, offering a novel pathway for enriching user-system engagements.
Kubernetes & AI - Beauty and the Beast !?! @KCD Istanbul 2024Tobias Schneck
As AI technology is pushing into IT I was wondering myself, as an “infrastructure container kubernetes guy”, how get this fancy AI technology get managed from an infrastructure operational view? Is it possible to apply our lovely cloud native principals as well? What benefit’s both technologies could bring to each other?
Let me take this questions and provide you a short journey through existing deployment models and use cases for AI software. On practical examples, we discuss what cloud/on-premise strategy we may need for applying it to our own infrastructure to get it to work from an enterprise perspective. I want to give an overview about infrastructure requirements and technologies, what could be beneficial or limiting your AI use cases in an enterprise environment. An interactive Demo will give you some insides, what approaches I got already working for real.
Software Delivery At the Speed of AI: Inflectra Invests In AI-Powered QualityInflectra
In this insightful webinar, Inflectra explores how artificial intelligence (AI) is transforming software development and testing. Discover how AI-powered tools are revolutionizing every stage of the software development lifecycle (SDLC), from design and prototyping to testing, deployment, and monitoring.
Learn about:
• The Future of Testing: How AI is shifting testing towards verification, analysis, and higher-level skills, while reducing repetitive tasks.
• Test Automation: How AI-powered test case generation, optimization, and self-healing tests are making testing more efficient and effective.
• Visual Testing: Explore the emerging capabilities of AI in visual testing and how it's set to revolutionize UI verification.
• Inflectra's AI Solutions: See demonstrations of Inflectra's cutting-edge AI tools like the ChatGPT plugin and Azure Open AI platform, designed to streamline your testing process.
Whether you're a developer, tester, or QA professional, this webinar will give you valuable insights into how AI is shaping the future of software delivery.
1. Performance Evaluation of IEEE 802.11p for
Vehicular Communication Networks
A. Jafari, S. Al-Khayatt and A. Dogman
Faculty of Art, Computing, Engineering and Sciences, Sheffield Hallam University, Sheffield, United Kingdom
Email: Amir.Jafari@student.shu.ac.uk; s.alkhayatt@shu.ac.uk; aadogman@my.shu.ac.uk
Abstract— IEEE 802.11p is an emerging standard which vehicles. Due to the characteristics of VANET and limited
provides vehicular safety communication through wireless bandwidth, periodic broadcast messages can consume the
networks. In this paper, the architecture of Wireless Access entire available bandwidth. Furthermore; the emergency
for Vehicular Environment (WAVE) and IEEE 802.11p messages need to be disseminated quickly and efficiently.
standard were analysed. The key parameters of this Consequently, there is a need to prioritise important and
standard are implemented in ns-2 network simulator to time-critical messages and use quality of services. The
accurately simulate vehicular ad hoc networks (VANETs). IEEE 802.11p MAC layer implements a priority scheme
The performance of this standard was measured in ns-2 in a similar way to IEEE 802.11e EDCA function.
network simulation environment using realistic vehicular
The contribution of this paper is to evaluate the IEEE
mobility models. The main performance metrics for
802.11p standard. A study was based on the structure of
vehicular safety communication; Throughput, End-to-End
the WAVE architecture for VANETs. We, subsequently,
delay, and Packet loss ratio were analysed for our scenario.
set up one real scenario which assisted us in analysing the
In addition, the effect of varying vehicle speed and different
message sizes on the performance metrics were measured.
performance metrics of the IEEE 802.11p. This scenario
was implemented and modelled using ns-2 network
I. INTRODUCTION simulator [2] with VanetMobiSim traffic simulator [3].
One of the most important points in the vehicular network
Intelligent Transportation System (ITS) is one of the simulation was that the nature of vehicular communication
information and communication technologies which has is based on the movement. Therefore, it is necessary to
attracted a lot of attention recently. This technology implement a realistic vehicular movement in the
enhances transportation safety, reliability, security and simulation. The main novelty of this paper is to implement
productivity by integrating with existing technologies. the key parameters of 802.11p standard in ns-2, and
Wireless data communication between vehicles is one of prepare the realistic vehicular mobility model by
the technologies which has improved the deployment of VanetMobiSim. In other words, all of the important
ITS applications. This communication is divided into two parameters are implemented accurately in the VANET
types: Vehicle to Vehicle (V2V) and Vehicle to simulation.
Infrastructure (V2I). Vehicles are equipped with short
range wireless communication technology (approximately Several publications [4], [5], [6] have studied the
100 to 300 metres) acting as computer nodes on the road. performance of 802.11p. However, none of the previous
This is known as vehicular ad hoc network (VANET) studies have supported realistic vehicular mobility
technology. The major objectives of VANET technology simulation. In [7], the authors have presented a
can be stated as follows: broadcasts warning messages to comprehensive evaluation and review of the performance
neighbouring vehicles in case of car accidents help of 802.11p and WAVE protocols supporting realistic
emergency vehicles to pass other vehicles quickly, and vehicular mobility model. However, standards were
provides drivers with latest real-time traffic information. implemented in Qualnet network simulator. In terms of
modelling accuracy, a new model of IEEE 802.11 MAC
A wide range of project activities have initiated around and PHY, which support IEEE 802.11P, is designed and
the world in order to improve vehicular communication implemented in ns-2 network simulator version 2.34 [8].
networks. In 2004, IEEE 802.11 task group p developed This version of ns-2 network simulator is used in this
an amendment to the 802.11 standard in order to enhance paper.
the 802.11 to support VANETs. This standard is known as
802.11p, it defines physical and medium access control The remainder of this paper is organised as follows. In
layers of VANETs. In addition, The IEEE 1609 working section II the WAVE and IEEE802.11p structure are
group defined IEEE 1609 protocol family which clarified. The simulation scenario is conducted in section
developed higher layer specification based on 802.11p. III. Results from the simulation and the analyses of the
This protocol consists of four documents: IEEE 1609.1, performance metrics of the IEEE 802.11p are presented in
IEEE 1609.2, IEEE 1609.3, and IEEE 1609.4. IEEE 1609 section IV. Finally, this paper is concluded in Section V.
protocol family and 802.11p together are called WAVE II. VEHICULAR COMMUNICATION BASED ON THE
standard. This system architecture is used for automotive
IEEE 802.11P AND WAVE SYSTEM
wireless communications [1].
The specific nature of VANET makes it different from In this section we briefly present an outline of WAVE
other kinds of networks; some of the characteristics of architecture system and IEEE 802.11p protocol for
VANET are high mobility, short communication periods, VANET.
dynamic topology and limited bandwidth. Communication
in VANETs is based on event-driven messages or
broadcast messages exchanged between surrounding
2. A. Physical and MAC Layers The contention procedure between channels to
The physical and MAC layers of WAVE are based on access the medium supported by different timer
IEEE 802.11p standard. The physical layer of IEEE settings based on the internal contention
802.11p consists of seven channels in 5.9GHz band which procedure. [7]
is similar to IEEE 802.11a design, but the main difference Logical link control (LLC) is another element of
is that the IEEE 802.11p uses 10MHZ bandwidth for each WAVE structure which is similar to upper sub-layer of
channel instead of 20MHZ bandwidth in IEEE 802.11a. OSI layer two. LLC provides the communication between
The physical layer of 802.11p uses OFDM technology in upper layers and the lower layer.
order to increase data transmission rate and overcome
signal fading in wireless communication. One of the C. Network and Transport Layers
specifications of IEEE 802.11p is that the management The IEEE 1609.3 defines the operation of services at
functions are connected to the physical and MAC layers network and transport layers. Moreover, it provides
called physical layer management entity (PLME) and wireless connectivity between vehicles, and vehicles to
MAC layer management entity (MLME), respectively [4]. roadside devices. The functions of the WAVE network
The IEEE 802.11p uses CSMA/CA to reduce collisions services can be separated into two sets:
and provide fair access to the channel. Data-plane services: They transmit network
traffics and support IPV6 and WSMP protocols.
Resource Manager Security WAVE short-message- Protocol (WSMP)
IEEE 1609.1 Services provides this capability that applications can send
UDP/TCP WSMP IEEE
IPV6 WME 1609.2 short message to increase the probability of
LLC IEEE receiving the messages in time.
Multi Channel Operation 1609.3 Management-plane services: Their functions are
IEEE 1609.4 to configure and maintain system, for instance:
WAVE MAC MLME IPV6 configuration, channel usage monitoring,
IEEE 802.11p and application registration. This service is
WAVE PHY PLME
IEEE 802.11p
known as WAVE management entity (WME).
Figure 1. WAVE Architecture D. Resource Manager
B. Multichannel Operation IEEE 1609.1 standard defines a WAVE application
known as resource manager (RM) which allows
IEEE 1609.4 is one of the standards of the IEEE 1609 communication between applications runs on Roadside
protocol family, which manages channel coordination and units (RSU) and On-board units (OBU). The RM resides
supports MAC service data unit delivery. This standard on either OBUs or RSUs [10].
describes seven different channels with different features
and usages (six service channels and one control channel). E. Security Services
In addition, these channels use different frequencies and The IEEE 1609.2 standard defines security services for
transmit powers. Eichler [4] mentions that each station the WAVE architecture and the applications which run
continuously alternates between the control channel and
one of the service channels; however the different through this architecture. This standard defines the format
channels cannot be used at the same time. According to and the processing of secure messages [1].
[9], the control channel is used for system control and
safety data transmission. III. SIMULATION
The IEEE 802.11p MAC layer is based on multichannel Implementing and deploying VANETs in a real world
operation of WAVE architecture and 802.11e EDCA. can be prohibitively expensive and difficult.
EDCA mechanism defines four different access categories Consequently, most of the researches in the area of
(AC) for each channel. The access categories are indicated Vehicular communication network are based on
by AC0-AC3, and each of them has an independent queue simulation for evaluation [11].
[4]. The EDCA mechanism provides prioritization by Simulation in VANET consists of two components:
assigning different contention parameters to each access traffic simulation and network simulation. Traffic
category. AC3 has the highest priority to access medium, simulation focuses on vehicular mobility and it generates
whereas AC0 has the lowest priority. Each frame is a trace file which provides realistic vehicles movement.
categorized into different access categories, depending on This trace file is fed into the network simulator which
the importance of the message. In IEEE 802.11p MAC defines the realistic position of each vehicle during the
layer, there are six service channels and one control network simulation. The network simulator then
channel and each of them has four different access implements the VANET protocols and produces a trace
categories. Consequently, during data transmission, there file which prepares complete information about the events
are two contention procedures to access the medium: taking place in the scenario. Information is then analysed
Internal contention procedure which occurs to evaluate the performance metrics of the IEEE 802.11p
inside each channel between their access in VANET.
categories by using the contention parameters VanetMobiSim is selected as a traffic simulator for this
(Arbitrary InterFrame space (AIFS) and paper, since it is an open source and is validated against
Contention Window (CW)). commercial simulators. This simulator supports Intelligent
DriverModel with Intersection Management (IDMIM)
which generates realistic vehicular mobility model [12].
3. Jiang et al. [13] mention that vehicular safety 170
communications based on IEEE 802.11p consist of safety 160
150
broadcast messages between neighbouring vehicles. 140
130
Consequently, the overall IEEE 802.11p performance is 120
Distance (m)
110
related to broadcast messages reception performance. PBC 100
90
agent is a broadcast message generator implemented in ns- 80
70
2 version 2.34. We used this agent in order to define the 60
50
broadcast message generation behaviour in our simulation. 40
30
20
The scenario is a highway of 1500 metres long with three 10
0
lanes in one direction and nine vehicles moving in these
0 6 12 18 24 30 36 42 48 54 60
three lanes. The maximum speeds of the lanes are around
Vehicle 2
80, 100 and 130 km/h respectively. The speed limit for Simulation Time (s)
Vehicle 4
each lane is 60 km/h. The distance between each lane is 4
metres. In the scenario, an ambulance is in the emergency Vehicle 10
situation travelling in the same direction as other vehicles Figure 3. Distance between the ambulance and other vehicles during
at the speed of 150 km/h. The ambulance is located behind movement
other cars which are 100 metres apart. The IDMIM
generates realistic vehicular mobility model. The Packet loss (%)
ambulance transmits one periodic broadcast message with
a payload of 250 bytes in every 0.2 seconds. In order to
evaluate the effect of different message sizes on the
performance metrics, we implemented another two
scenarios in which the ambulance transmits period
broadcast messages with the payload of 500, 1000 bytes
respectively. Each network simulations run twenty times
with the same mobility trace to obtain an average and get
a notion of statistical significance.
▬Packet loss between vehicle 1 and 2
▬Packet loss between vehicle 1 and 4 Simulation Time (s)
▬Packet loss between vehicle 1 and 10
Figure 4. Packet loss between the ambulance and other vehicles during
movement
Figure 2. Scenario
IV. RESULTS Fig. 5 demonstrates the throughput of vehicles 2, 4, and
10 with the message size of 250 bytes. The figure shows
Results obtained from the scenario previously described that the throughput of vehicles 4 and 10 fluctuate between
are presented in this section. Throughput, End-to-End 1.8 and 2.2 Kbps, when the distances between the vehicles
delay, and packet loss were calculated for nine vehicles as and the ambulance are less than 138 metres. It can be seen
numbered in Fig. 2 during the simulation run-time (i.e. 65 from Fig. 5 that all of the vehicles have nearly similar
seconds). In addition, the impact of various speeds on throughput when the distances between vehicles and
different performance metrics was also evaluated. ambulance are less than 138 metres. In other words,
Fig. 3 shows the distances between the ambulance and throughput of all the vehicles which their distances do not
vehicles 2, 4, and 10 throughout the simulation . Also, exceed 138 metres from the ambulance are same and there
Packet loss between the ambulance and these vehicles is no packet loss between these vehicles and ambulance.
during the simulation time is illustrated in Fig. 4. It is The most important point is that each vehicle has different
clearly shown in Fig. 4 that there is no packet loss speed, as a result the throughput and packet loss are not
between the ambulance and vehicle 4 after 58 seconds of affected by the varying speed.
the simulation time; regarding to Fig. 3, the distance
6.4
between the ambulance and vehicle 4 is less than 138 5.9
metres after 58 seconds. Fig.4 shows that packet loss is 5.4
dropped to 0% after 38 seconds of simulation, at the same 4.9
Throughput (kbps)
time Fig. 3 demonstrates that the distance between 4.4
3.9
ambulance and vehicle 10 is less than 138 metres after 38 3.4
seconds. It provides similar results for vehicle 10 and 4. 2.9
Accordingly, the vehicles can receive the broadcast 2.4
1.9
message when their distance from the ambulance is less 1.4
than 138 metres. 0.9
0.4
-0.1
0
0 10 20 30 40 50 60
Simualtion Time (s)
Figure 5. Throughput of vehicle 2,4, and 10 (message size 250 bytes)
4. 180
End-to-End delay between the ambulance and vehicles 160
2, 4, and 10 with the message size of 250 bytes are shown
Average Distance (m)
140
in Fig. 6. A comparison between Fig. 3 and Fig. 6 shows 120
that as long as the distance between vehicle and the 100
ambulance is below 138 metres, the results of both figures 80
look similar. As the distance between sender and receiver 60
40
increases, End-to-End delay increases accordingly. It is
20
observed that End-to-End delay is significantly influenced 0
by the distance between sender and receiver of the 2 3 4 5 6 7 8 9 10
message. As mentioned earlier, vehicles have different Vehicle Numbers
speed; consequently, various vehicle speeds do not have
any impact on End-to-End delay. Figure 8. Average distance between the ambulance and other vehicles
(message size 250 bytes)
0.4665
100
0.46645
90
0.4664 80
End-to-End Delay (ms)
Package Loss (%)
0.46635 70
60
Average
0.4663
50
0.46625
40
0.4662 30
0.46615 20
10
0.4661
0
0.46605
2 3 4 5 6 7 8 9 10
0.466 Vehicle Numbers
0 5 10 15 20 25 30 35 40 45 50 55 60 65
End-to-End Delay between vehicle 1 and 2
Simulation Time (s)
Figure 9. Average packet loss between the ambulance and other
End-to-End Delay between vehicle 1 and 4
vehicles (message size of 250 bytes)
End-to-End Delay Between vehicle 1 and 10
Fig. 10 and Fig. 11 illustrate the average throughput and
End-to-End delay with three different message sizes (250,
Figure 6. End-to-End delay between the ambulance and other vehicles 500, 1000 bytes). According to these figures the average
(message size 250 bytes) throughput and End-to-End delay are increased by
increasing the message size, but the increment of
Fig. 7, Fig. 8 and Fig. 9 illustrate the average throughput of vehicles 4, 7, and 10 is not as high as other
throughput, distance and packet loss between all vehicles vehicles.
and the ambulance respectively. The probability of
message reception for vehicles 4, 7 and 10 is less than 10
other vehicles and they have the highest average packet
Average Throughput (kbps)
9
8
loss, since their average distance is more than other 7
vehicles and at the beginning of simulation their distance 6
5
from the ambulance is more than 138 metres. However 4
other vehicles, which their distances do not exceed 138 3
metres from the ambulance during simulation time, have 2
1
equal and highest rate of average throughout without any 0
packet loss. This is another reason indicating that 0 1 2 3 4 5 6 7 8 9 10
throughput and packet loss are not influenced by different Message size 250 bytes
Vehicle Numbers
vehicle speed. Message size 500 bytes
Message size 1000 bytes
1.8
Average Throughput (kbps)
Figure 10. Average throughput of vehicles with different message sizes
1.5
1.2
0.9
0.6
0.3
0
2 3 4 5 6 7 8 9 10
Vehicle Numbers
Figure 7. Average throughput of vehicles (message size 250 bytes)
5. [9] M. Amadeo, C. Campolo, and A. Molinaro, "Enhancing IEEE
1.6 802.11p/WAVE to provide infotainment applications in
Average End-toEnd Delay (ms)
1.4 VANETs," Ad Hoc Networks, Elsevier, 2010.
1.2 [10] WILLIAMS, B. “Intelligent Transport Systems Standards,” Artech
1 House Publishers, 2008.
0.8 [11] S. Olariu and M. Weigle, Eds., “Vehicular Networks: From
0.6 Theory to Practice,” Chapman & Hall/CRC, 2009.
0.4 [12] J. Härri, F. Filali, and C. Bonnet, “Mobility Models for Vehicular
0.2 Ad Hoc Networks: A Survey and Taxonomy,” research rep. RR-
0 06-168, Institut Eurecom, Mar. 2007.
0 1 2 3 4 5 6 7 8 9 10 [13] D. Jiang, V. Taliwal, A. Meier, W. Holfelder, and R. Herrtwich,
“Design of 5.9 GHz DSRC-based vehicular safety
Message size 250 bytes
Vehicle Numbers communication,” IEEE Wireless Communications, vol. 13, no. 5,
Message size 500 bytes pp. 36–43, Oct. 2006.
Message size 1000 bytes
Figure 11. Average End-to-End delay between the ambulance and other
vehicles with different message size
V. CONCLUSION
In this paper we studied the full details of the WAVE
architecture and IEEE 802.11p standard for vehicular ad
hoc networks (VANET). We implemented the key
parameters of 802.11p in ns-2 network simulation using
realistic vehicular mobility model generated by
VanetMobisim traffic simulation. One scenario was
implemented in the simulation. We analysed three
important metrics in order to evaluate the performance of
IEEE 802.11p standards. Based on our findings, we have
observed that the performance metrics (throughput, End-
to-End delay, and packet loss) are not affected by varying
vehicle speed. Analysis of throughput for the all vehicles
showed that the probability of successful message
reception was same for all the vehicles when the distance
between sender and receiver of the message was less than
138 metres. In addition, End-to-end delay metric was
directly related to the distance between the vehicle
transmitting the broadcast messages and its neighbouring
vehicles. Results of scenarios with different message sizes
demonstrated that the average throughput and End-to-End
delay metrics were increased by increasing message sizes.
REFERENCES
[1] R. A. Uzcátegui and G. Acosta-Marum, “WAVE: A Tutorial,”
IEEE Commun. Mag., May 2009.
[2] “Network Simulator ns-2,” http://www.isi.edu/nsnam/ns.
[3] “VanetMobiSim, ” http://vanet.eurecom.fr.
[4] S. Eichler, “Performance evaluation of the IEEE 802.11p WAVE
communication standard,” in Proc. IEEE Vehicular Technology
Conf., Baltimore, MD, US, Oct. 2007, pp. 2199-2203.
[5] T. Murray, M. Cojocari, H. Fu, “Measuring the performance of
IEEE 802.11p using ns-2 simulator for vehicular networks,” in:
Proc. IEEE EIT, 2008, pp. 98–503.
[6] K. Bilstrup, E. Uhlemann, E. G. Ström and U. Bilstrup,
“Evaluation of the IEEE 802.11p MAC method for vehicle-to-
vehicle communication,” Proc. IEEE Int. Symposium on Wireless
Vehicular Communications, Calgary, Canada, Sept. 2008.
[7] S. Grafling, P. Mahonen, and J. Riihijarvi, “Performance
evaluation of IEEE 1609 WAVE and IEEE 802.11p for vehicular
communications,” in Proceedings of the 2nd International
Conference on Ubiquitous and Future Networks (ICUFN ’10),
June 2010, pp. 344 –348.
[8] Q. Chen, F. Schmidt-Eisenlohr, D. Jiang, M. Torrent-Moreno, L.
Delgrossi, and H. Hartenstein, “Overhaul of IEEE 802.11
modeling and simulation in ns-2,” in Proc. 10th ACM Symp.
MSWiM, Chania, Greece, Oct. 2007, pp. 159–168.