Implementing congestion control in the real world

It is well known that congestion control is a key issue for the safe deployment of multimedia applications over IP. We describe our initial experiences implementing TCP-friendly congestion control in a system designed to deliver HDTV content over IP networks. In particular we discuss the effects of packet reordering on the calculated throughput, and highlight the problems this can pose for high-rate applications

Integrated Freeway and Arterial Traffic Control to Improve Freeway Mobility without Compromising Arterial Traffic Conditions Using Q-Learning

Freeway and arterial transportation networks are operated individually in most cities nowadays. The lack of coordination between the two increases the severity of traffic congestion when they are heavily loaded. To address the issue, we propose an integrated traffic control strategy that coordinates freeway traffic control (variable speed limit control, lane change recommendations, ramp metering) and arterial signal timing using Q-learning. The agent is trained offline in a single-section road network first, and then implemented online in a large simulation network with real-world traffic demands. The online data are collected to further improve the agent's performance via continuous learning. We observe significant reductions in freeway travel time and number of stops and a slight increase in on-ramp queue lengths by implementing the proposed approach in scenarios with traffic congestion. Meanwhile, the queue lengths of adjacent arterial intersections are maintained at the same level. The benefits of the coordination mechanism is verified by comparing the proposed approach with an uncoordinated Q-learning algorithm and a decentralized feedback control strategy.Comment: 12 pages, 10 figures, 5 table

Influence of Wireless Novel Routing Protocol by Using MDPC Algorithm

This research study investigates the influence of a novel wireless routing protocol that incorporates the MDPC (Multiplicative-Divisive Probabilistic Congestion Control) algorithm. The background of the research stems from the increasing demand for efficient and reliable routing protocols in wireless networks, which face challenges such as limited bandwidth, variable network topologies, and dynamic environmental conditions. The purpose of this study is to evaluate the performance of the proposed routing protocol and assess its effectiveness in addressing these challenges. To achieve this objective, a series of methodologies were employed. First, an in-depth analysis of existing routing protocols was conducted to identify their limitations and areas for improvement. The simulations were conducted in controlled environments, and real-world deployment scenarios may introduce additional challenges that need to be addressed. Furthermore, practical implications of implementing the protocol, such as hardware and software compatibility, scalability, and security considerations, should be thoroughly investigated before widespread adoption

Achieving genuinely dynamic road user charging : issues with a GNSS-based approach

Peer reviewedPostprin

Evaluation of the implementation process of urban road pricing schemes in the United Kingdom and Italy

This paper is based upon detailed research that has taken place in the UK and Italy, on the implementation strategies for urban road pricing schemes. In the UK, both in London and Durham, the Road User Charging schemes required new legislation, and were implemented rapidly. The time from announcement to implementation took three years and the schemes were introduced after short periods of intensive planning, consultations and stakeholder networking. In Italy, the situation has been very different. The road pricing schemes in Rome and Genoa were not introduced under specific legislation but rather evolved from access control zones originally implemented in historic urban centres. The incremental introduction of the Italian road pricing experiments has taken approximately ten years. The paper undertakes a comparison of these different strategies to introduce urban road pricing and the lessons they contain for the development of similar measures elsewhere. The comparison of the different implementing experiences is undertaken using Strategic Policy Niche Management, a method designed to explore, among other factors, the dynamics of the stakeholder networks involved in planning, introducing, marketing and managing radical urban Travel Demand Management policies

Network emulation focusing on QoS-Oriented satellite communication

This chapter proposes network emulation basics and a complete case study of QoS-oriented Satellite Communication

Analysing road pricing implementation processes in the UK and Norway

Traditional transport policies of road expansion entail a relatively simple system of actors and processes around which expertise, knowledge, and skills which has built up over many decades. Some of the more radical Travel Demand Management measures, including urban road pricing, involve a complicated set of institutions, processes, people and procedures. Road pricing schemes often get delayed or abandoned due to controversy, disagreements, unanticipated problems and a whole host of other delaying factors. If they are implemented, they tend to be diluted and consequently become less effective. Strategic Niche Management (SNM) has previously been used to provide guidelines on the implementation of innovative transport technologies through setting up protected experimental settings (niches) in which actors learn about the design, user needs, social and political acceptability, and other aspects. Here SNM is modified to cover a policy approach through the analysis of road user charging case studies in the UK and Norway. A detailed analysis of the road user charging schemes in Bergen, Oslo, Durham and London is presented. Key factors identified include the role of stakeholder and user networks, the existence of a project champion, understanding the motivations and expectations of stakeholders and users, learning with regards to the regional context, and the change in perceptions associated with acceptance. Comparison between the four cases shows different approaches emerging from each country in implementing and ‘marketing’ of the policies. The paper concentrates on approaches such as: the purpose for introducing the policies, the involvement of users in the planning process and, the use of revenues for either providing alternative transport modes or financing road infrastructure. Key factors identified using the SNM framework include the role of stakeholder and user networks, the existence of a project champion, understanding the motivations and expectations of stakeholders and users, learning with regards to the regional context, and the change in perceptions associated with acceptance. This type of analysis could prove useful for transport planners envisaging the implementation of road pricing projects