Adaptive Management of Volatile Edge Systems at Runtime With Satisfiability

Edge computing offers the possibility of deploying applications at the edge of the network. To take advantage of available devices’ distributed resources, applications often are structured as microservices, often having stringent requirements of low latency and high availability. However, a decentralized edge system that the application may be intended for is characterized by high volatility, due to devices making up the system being unreliable or leaving the network unexpectedly. This makes application deployment and assurance that it will continue to operate under volatility challenging. We propose an adaptive framework capable of deploying and efficiently maintaining a microservice-based application at runtime, by tackling two intertwined problems: (i) finding a microservice placement across device hosts and (ii) deriving invocation paths that serve it. Our objective is to maintain correct functionality by satisfying given requirements in terms of end-to-end latency and availability, in a volatile edge environment. We evaluate our solution quantitatively by considering performance and failure recovery.

Service Failure, Recovery, and Sustainable Development

Extant literature on corporate social responsibility (CSR) and marketing shows that CSR plays an important role when a service fails; thus, application of recovery strategy becomes crucial for sustainable development. CSR creates greater performance expectations amongst stakeholders as well as helps to legitimise organisational activities when a service fails. This study maintains that CSR is crucially important not only in legitimising organisational actions, but in ensuring that stakeholders' loyalty, trust, and justice are assured. This CSR, service failure, and recovery nexus is more needed in the controversial extractive industry in Nigeria, which has a history of illegitimacy, irresponsible corporate responsibility, lack of accountability, and failure of justice, which have triggered and sustained corporate-stakeholder conflict. This landscape has negative impact on sustainable development, peace, and justice in the Niger Delta region of Nigeria, where oil is extracted.

Automatic Failure Recovery for Container-Based IoT Edge Applications

Recent years have seen the rapid adoption of Internet of Things (IoT) technologies, where billions of physical devices are interconnected to provide data sensing, computing and actuating capabilities. IoT-based systems have been extensively deployed across various sectors, such as smart homes, smart cities, smart transport, smart logistics and so forth. Newer paradigms such as edge computing are developed to facilitate computation and data intelligence to be performed closer to IoT devices, hence reducing latency for time-sensitive tasks. However, IoT applications are increasingly being deployed in remote and difficult to reach areas for edge computing scenarios. These deployment locations make upgrading application and dealing with software failures difficult. IoT applications are also increasingly being deployed as containers which offer increased remote management ability but are more complex to configure. This paper proposes an approach for effectively managing, updating and re-configuring container-based IoT software as efficiently, scalably and reliably as possible with minimal downtime upon the detection of software failures. The approach is evaluated using docker container-based IoT application deployments in an edge computing scenario.

Routing Path Assignment for Joint Load Balancing and Fast Failure Recovery in IP Network

Distributed link-state routing protocols, including Open Shortest Path First (OSPF) and Intermediate System–Intermediate System (IS-IS), have successfully provided robust shortest path routing for IP networks. However, shortest path routing is inflexible and sometimes results in congestion on some critical links. By separating the control plane and the data plane, the centralized control of Software Defined Networking (SDN)-based approach possesses flexible routing capabilities. Fibbing is an approach that can achieve centralized control over a network running distributed routing protocols. In a Fibbing-controlled IP network, the controller cleverly generates fake protocol messages to manipulate routers to steer the flow of the desired paths. However, introducing fake nodes destroys the structure of the loop-free property of Loop-Free Alternate (LFA) that is used to achieve fast failure recovery in IP networks. This paper addresses this issue and presents a solution to provision routing paths so a Fibbing network can still apply LFA in the network. The proposed network jointly considers load-balanced and fast failure recovery. We formulate the problem as an integer linear programming problem. The numerical results reveal that the proposed method can provide 100% survivability against any single node or single link failure.

Coordination of synchronous compensators and converters to improve the commutation failure recovery performance in HVDC systems

A novel control strategy of synchronous compensators and converters is proposed to increase the ability of line commutated converter (LCC) based HVDC systems to successfully recover from commutation failures (CFs). The dynamic var support is one of the most important factors, which impact the commutation process. Many synchronous compensators have been implemented to enhance the transient voltage stability for improving the CF recovery performance. However, the traditional automatic voltage regulator (AVR) of synchronous compensator may not be suitable for the commutation voltage support, because the transient var demand of converters during the CF recovery is neglected. In our work, the voltage control will be adaptively adjusted, depending on the state of converters. Case studies based on simulations in PSCAD/EMTDC show that the proposed strategy can improve the performance of fault recovery from CF.