Cloud-based Network Virtualization in IoT with OpenStack

In Cloud computing deployments, specifically in the Infrastructure-as-a-Service (IaaS) model, networking is one of the core enabling facilities provided for the users. The IaaS approach ensures significant flexibility and manageability, since the networking resources and topologies are entirely under users’ control. In this context, considerable efforts have been devoted to promoting the Cloud paradigm as a suitable solution for managing IoT environments. Deep and genuine integration between the two ecosystems, Cloud and IoT, may only be attainable at the IaaS level. In light of extending the IoT domain capabilities’ with Cloud-based mechanisms akin to the IaaS Cloud model, network virtualization is a fundamental enabler of infrastructure-oriented IoT deployments. Indeed, an IoT deployment without networking resilience and adaptability makes it unsuitable to meet user-level demands and services’ requirements. Such a limitation makes the IoT-based services adopted in very specific and statically defined scenarios, thus leading to limited plurality and diversity of use cases. This article presents a Cloud-based approach for network virtualization in an IoT context using the de-facto standard IaaS middleware, OpenStack, and its networking subsystem, Neutron. OpenStack is being extended to enable the instantiation of virtual/overlay networks between Cloud-based instances (e.g., virtual machines, containers, and bare metal servers) and/or geographically distributed IoT nodes deployed at the network edge.

Insights from systematic literature review of supply chain resilience and disruption

PurposeThe study of supply chain disruption (SCD) and supply chain resilience (SCR) remains to be studied deeply in the field of business management. The purpose of this paper is to showcase a framework of SCR strategies to reduce the adverse effects of SCD using systematic literature review and data visualization.Design/methodology/approachUsing a systematic literature review approach, the paper explores the concepts of supply chain disruption and supply chain resilience. Through rigorous systematic screening, authors studied papers on both the concepts and have proposed a framework for the same. The authors also have used data visualization and network diagram approaches for better understanding of the topic.FindingsThe systematic literature review of both the concepts brings out some exciting results which give a new direction to supply chain field. The outcome of this research also outlines numerous future research direction, which will be useful for the research community.Practical implicationsThe numerous strategies of SCR should be implemented by manufacturing as well as a service organization. The framework reported in this research help academician and practitioners to understand SCR and to easily overcome any level of disruption. Supply chain managers must also formulate strategies accordingly and make plans to continually expand the system.Originality/valueThis research is the first such attempt to showcase a formal systematic framework and co-occurrence networks as well as overlay networks of SCR and SCD.

Comparative analysis of routing techniques in chord overlay network

Overlay networks are not a new field or area of study. This domain of computing will someday drive P2P systems in various application areas such as block-chain, energy trading, video multicasting, and distributed file storage. This study highlights the two widely known methods of routing information employed in one of such overlay networks called chord. In this study, simulations of both routing modes (iterative and recursive) and their variations under no-churn (leaving and joining of nodes) and churn conditions was carried out. The routing parameter (successor list size) was varied for each of the routing techniques in a simulation study. The results obtained show that semi recursive routing gives a better routing performance under churn scenarios.

Efficient Communication Protocols for Non DHT-based Pyramid Tree P2P Architecture

In this paper, we have considered a recently reported 2-layer non-DHT-based structured P2P network. Residue Class based on modular arithmetic has been used to realize the overlay topology. At the heart of the architecture (layer-1), there exists a tree like structure, known as pyramid tree. It is not a conventional tree. A node i in this tree represents the cluster-head of a cluster of peers which are interested in a particular resource of type Ri (i.e. peers with a common interest). The cluster-head is the first among these peers to join the system. Root of the tree is assumed to be at level 1. Such a tree is a complete one if at each level j, there are j number of nodes. It is an incomplete one if only at its leaf level, say k, there are less than k number of nodes. Layer 2 consists of the different clusters. The network has some unique structural properties, e.g. each cluster has a diameter of only 1 overlay hop and the diameter of the network is just (2+2d); d being the number of levels of the layer-1 pyramid tree and d depends only on the number of distinct resources. Therefore, the diameter of the network is independent of the number of peers in the whole network. In the present work, we have used some such properties to design low latency intra and inter cluster data lookup protocols. Our choice of considering non-DHT and interest-based overlay networks is justified by the following facts: 1) intra-cluster data lookup protocol has constant complexity and complexity of inter-cluster data lookup is O(d) if tree traversal is used and 2) search latency is independent of the total number of peers present in the overlay network unlike any structured DHT-based network (as a matter fact unlike any existing P2P network, structured or unstructured). Experimental results as well show superiority of the proposed protocols to some noted structured networks from the viewpoints of search latency and complexity involved in it. In addition, we have presented in detail the process of handling churns and proposed a simple yet very effective technique related to cluster partitioning, which, in turn, helps in reducing the number of messages required to be exchanged to handle churns.