Connection management for QoS service on the Web

The current World Wide Web service model treats all requests equivalently, both while being processed by servers and while being transmitted over the network. For some uses, such as Web prefetching or multiple priority schemes, different levels of service are desirable. This paper presents three simple, server-side, application-level mechanisms (limiting process pool size, lowering process priorities, limiting transmission rate) to provide two different levels of Web service (regular and low priority). We evaluated the performance of these mechanisms under combinations of two foreground workloads (light and heavy) and two levels of available network bandwidth (10 Mb/s and 100 Mb/s). Our experiments show that even with background traffic sufficient to saturate the network, foreground performance is reduced by at most 4–17%. Thus, our user-level mechanisms can effectively provide different service classes even in the absence of operating system and network support.

The study presented in this paper aims to quantify the impact of level of service on real time crash risks on freeways and to investigate the mechanisms of crash occurrences in different level of service. Using crash data and paired traffic data extracted from a northbound segment of the I-880 freeway in the United States, a conditional logit model is conducted to relate the crash risks to levels of service. It is found that LOS E had the greatest impact on crash occurrences on freeways, followed by LOS F and LOS D, and the crash risks associated with LOS B are not significantly different from those associated with LOS A. The random forest algorithm is further conducted to identify the contributing factors to crash occurrence in different LOS. The findings of random forest demonstrate that the mechanisms of crash occurrence are quite different across different levels of service. The vehicle platoon and abrupt change in vehicle speed contribute to the crash risks in LOS A and B. In LOS C or LOS D, lane changes have impacts on crash risks, and the high crash risks associated with LOS E are mainly caused by high traffic volumes and oscillating traffic conditions. The findings of this study suggests that different traffic management strategies should be developed in dynamic freeway traffic management systems based on the contributing factors to crash occurrences in different levels of service.

Introduction: Children and young people (CYP) with medical complexity, have high levels of healthcare needs and utilisation, representing 10% of patients attending children’s hospitals, and accounting for 60% of healthcare expenditure in the state of New South Wales (NSW), Australia. Furthermore, 30% of children in NSW live outside major cities and require enhanced local health solutions to manage healthcare needs, reduce travel and family disruptions and limit out-of-pocket expenses. The Rural Kids Guided Personalised Service (RuralKidsGPS) is a co-designed innovative integrated model of care coordination for CYP living with medical complexity, modelled on the successfully implemented and sustained KidsGPS program in tertiary children’s hospitals in Sydney. RuralKidsGPS is being implemented into four rural local health districts (LHDs) across NSW. This study explores early implementation barriers and enablers to inform contextual adaption and ensure scalability across diverse health settings. Methods: The implementation evaluation is informed by qualitative methods using semi-structured interviews and focus groups, with children and families, healthcare providers embedded researchers, and health service managers. Adopting an inductive approach underpinned by the Consolidated Framework for Implementation Research (CFIR), we identify implementation strategies, barriers and enablers influencing adoption, delivery, and sustainability of RuralKidsGPS. In this early phase of implementation evaluation (6-12 month after commencement) we have focused on implementation outcomes based on Proctor’s framework, including acceptability, appropriateness, adaptability, fidelity, and feasibility. Results: The interviews demonstrated the variations in setting and context across the LHDs and the adaption of RuralKidsGPS to meet local needs. Different levels of service demand, the time required for engagement with families from diverse socio-economic and cultural backgrounds and different levels of pre-existing service, and staff changes, contribute to the complexity of service implementation and delivery. All four LHDs share borders with jurisdictions outside of NSW, resulting in some children traveling across state or territory borders to access specialist health services. The complexities of sharing and gaining access to healthcare information across jurisdictions has impacted the timely delivery of care coordination and shared care plan development. RuralKidsGPS builds local healthcare capacity to manage CYP living with medical complexity but requires commitment and effort to build relationships with established local services and understanding of processes, and values, whilst conserving local resources. The perceived value and commitment to RuralKidsGPS by nurse care coordinators who leverage local knowledge and networks to deliver family-centred care, is a key enabler. Importantly, reciprocal support from health managers and health care professionals, and access to resources and networks is providing nurse coordinators the power to adapt and implement RuralKidsGPS. During this period, all LHDs were impacted by natural disasters (floods, bushfires) and COVID-19 creating barriers that required those implementing the RuralKidsGPS to flex and adapt. Conclusion: Early findings highlight the importance of adaptation to local contexts, the challenges and barriers and the resilience of the care coordinators implementing RuralKidsGPS. Care coordination enables families to navigate fragmented, complex health care systems, more efficiently and effectively. This research will inform the development of an implementation guide to support scaling and sustaining similar models of paediatric integrated care.

Wavelength division multiplexing/time division multiplexing (WDM/TDM) passive optical networks (PON) is being viewed as a promising solution for delivering multiple services and applications. The hybrid WDM / TDM PON uses the wavelength and bandwidth allocation strategy to control the distribution of the wavelength channels in the uplink direction, so that it can ensure the high bandwidth requirements of multiple Optical Network Units (ONUs) while improving the wavelength resource utilization. Through the investigation of the presented dynamic bandwidth allocation algorithms, these algorithms can't satisfy the requirements of different levels of service very well while adapting to the structural characteristics of mixed WDM / TDM PON system. This paper introduces a novel wavelength and bandwidth allocation algorithm to efficiently utilize the bandwidth and support QoS (Quality of Service) guarantees in WDM/TDM PON. Two priority based polling subcycles are introduced in order to increase system efficiency and improve system performance. The fixed priority polling subcycle and dynamic priority polling subcycle follow different principles to implement wavelength and bandwidth allocation according to the priority of different levels of service. A simulation was conducted to study the performance of the priority based polling in dynamic resource allocation algorithm in WDM/TDM PON. The results show that the performance of delay-sensitive services is greatly improved without degrading QoS guarantees for other services. Compared with the traditional dynamic bandwidth allocation algorithms, this algorithm can meet bandwidth needs of different priority traffic class, achieve low loss rate performance, and ensure real-time of high priority traffic class in terms of overall traffic on the network.

The widespread diffusion of distributed services, providing access to resources through the Net, has stressed the need of secure ways to authenticate users. The heterogeneity of resources leads to different authentication mechanisms implementations often requiring multiple log-on actions also in intra-domain multi-services scenario. The article presents a roadmap on authentication mechanisms implemented at different levels of services’ software structure.

A given infrastructure system has different levels of service (LOS) for different users. To date, limited work has been done to combine these LOS to an asset level LOS. In addition, existing methods to determine LOS are based on the quantitative performance measures related to the capacity of the infrastructure systems. These methods neglect other qualitative factors, for example, neighborhood safety and appearance. This paper describes a proposed asset level of service (ALOS) determination methodology, which can be integrated with decision support systems (DSS) as a performance indicator. The proposed ALOS is a composite LOS for different users of the infrastructure system. Incorporation of ALOS with DSS will aid the municipalities in producing improved resource allocation plans in compliance with service standards, applicable codes, and regulations. In this paper, a framework of the development of ALOS in municipal infrastructure systems is presented. The analytical hierarchy process is used to model the ALOS. The developed framework is then applied to calculate the ALOS for the municipality/urban roads, to combine LOS for vehicle users, bicyclists, and pedestrians; accounting for qualitative factors, such as neighborhood safety and aesthetics.

1 - The Big Picture

The setup for the authors' problem consists of n servers that must complete a set of tasks. Each task can be handled only by a subset of the servers, requires a different level of service, and once assigned can not be re-assigned. They make the natural assumption that the level of service is known at arrival time, but that the duration of service is not. The on-line load balancing problem is to assign each task to an appropriate server in such a way that the maximum load on the servers is minimized. The authors derive matching upper and lower bounds for the competitive ratio of the on-line greedy algorithm for this problem, namely /sup (3n)2/3///sub 2/(1+o(1)), and derive a lower bound, Omega ( square root n), for any other deterministic or randomized on-line algorithm. >

M2I2tswTCM: A new efficient optimization marker algorithm to improve fairness bandwidth in DiffServ networks

Blockchain-based applications have been recently introduced in communication networks. Different applications require different levels of service whereas existing blockchain-based applications mostly provide a single class of service. In this paper, we propose a multi-class blockchain services (MCBS) framework that prioritizes the processing of time-critical blockchain-based applications in communication networks. We model MCBS as a queueing system and derive the average service times for the different classes. We then formulate a multi-objective optimization problem to simultaneously optimize the average service time and aggregate transactions arrival rate. The numerical results show that existing blockchains may not satisfy the requirements of time-critical applications whereas a high priority queue in MCBS may meet the requirement. In addition, we analyze MCBS under double-spend attacks and show that with maximum attacker hash power, the blockchain system can still be stable if the aggregate transaction arrival rate is lower than half of its maximum achievable value.

Home care clients have safety barriers related to medication storage, disposal, and safe use of opioids. Limited research is available regarding medication safety initiatives in the home care setting. This study evaluates a medication safety initiative, linked with opioid misuse and overdose prevention screening, for home care clients with different levels of service. Training and screening tools designed for community pharmacies by the Opioid & Naloxone Education (ONE) Program were modified for use by home health nurses. All new admits to the home health services were screened for medication storage, medication disposal, and use of pain medications. Patients taking opioids were screened for opioid-specific risks. Interventions based on screening results included education, provision of medication lock boxes, drug disposal packets, and/or naloxone. Most home care clients (85%) are properly storing their medication and 38% were not properly disposing unused medications. Higher levels of care had greater pain medication needs, including the provision of naloxone. This study demonstrates the opportunity to incorporate medication safety screening into nursing home health visits.

Water for the urban poor: Balancing financial and social objectives through service differentiation in the Kenyan water sector

Assuring the required quality of service, despite the growing volume and variety of Internet of Things (IoT) traffic, has remained an immense challenge in the popular WiFi networks. The IoT devices using short TCP flows often attain very different levels of service due to the complicated interactions between the transport layer protocol and the shared dynamic wireless medium. We develop in this paper a novel queue management policy by using a transient model to capture the interactions of IoT (short TCP) flows over traditional traffic in WiFi networks. Based on the Markov regenerative processes coupled with fluid model, we discover that the adaptive admission control (AAC) mechanism at the WiFi access point (AP) improves the response time and fairness of IoT traffic over the lossy WiFi links. To this end, under the proposed AAC, packets are admitted into the AP in such a way that the fractions of packets in the AP buffer belonging to the different IoT devices are balanced resulting in a comparable level of service. We furthermore prove the stability of the system dynamics under AAC which provides important practical insights in designing home WiFi IoT system.

We study a pricing problem that is motivated by the following examples. A cloud computing platform such as Amazon EC2 sells virtual machines to clients, each of who needs a different number of virtual machine hours. Similarly, cloud storage providers such as Dropbox have customers that require different amounts of storage. Software companies such as Microsoft sell software subscriptions that can have different levels of service. The levels could be the number of different documents you are allowed to create, or the number of hours you are allowed to use the software. Companies like Google and Microsoft sell API calls to artificial intelligence software such as face recognition, to other software developers. Video and mobile games are increasingly designed in such a way that one can pay for better access to certain features. Spotify and iTunes sell music subscription, and different people listen to different number of songs in a month. Cellphone service providers like AT&T and Verizon offer cellular phone call minutes and data. People have widely varying amounts of data consumption.

In conventional TCP/IP networks, there is a differentiated service architecture for providing different levels of services. Similarly in Delay Tolerant Networks (DTNs), we need to provide differentiated services where the network resources are limited, particularly in buffer size. Since DTNs have their own network characteristics, such as multiple copy routings, and intermittently connection, the traditional differentiated service architecture does not apply. In this paper, we propose two simple schemes to provide a packet forwarding assurance in DTNs. The two proposed schemes are an absolute differentiation scheme, and a relative differentiation scheme. These schemes have a prioritization process when a packet is dropped from the local buffer at each node to provide a high priority to Assured Forwarding (AF) packet and a low priority to Best Effort packet. We show that the proposed algorithms can dynamically find the appropriate target delivery ratio for AF packets, which can provide forwarding assurance for AF packets while avoiding starvation of BE packets, without any global information even though network conditions are changing. We believe that our study is the initial step toward exploiting differentiation services in DTNs.