Search

A wireless mesh network (WMN)-based disaster network shall provide an emergency communication infrastructure in case of a catastrophe destroyed any existing communication infrastructure. Since the hardware of the disaster network is deployed in an environment affected by the outcome of a catastrophe, events such as aftershocks and/or outbreaking fires are likely to occur and may destroy the hardware of the disaster network. To maintain its provided functionality and thus its usability, the network requires to be resilient to these and other events which are affecting the network infrastructure. To achieve a resilient network, the normal state of the network as well as possible challenges affecting the normal state need to be defined in prior. This scientific work deals with the derivation and definition of the required normal state of the WMN-based disaster network, as well as the definition of possible challenges resulting from environmental-based events. Since each possible challenge is influencing the network infrastructure of the WMN-based disaster network, possible measures for preventing and/or reducing the impact of each challenge are defined. In addition, emergency corrections capable of resolving the influences of an occurring challenge are defined.

The Wireless mesh network (WMN) is a popular network architecture used to support disaster recovery operations. However, few research works have addressed the capacity problem of such a network. This is due to the assumption that the communication network in disaster scenario is built to support services with a low rate requirement like delay tolerant messages. At the same time, the demand for higher data rates has increased in recent years due to the digitalisation of rescue operations and the use of new services (e.g. VoIP, drones and robots). Therefore, the capacity of the WMN is becoming a central issue in the design of future WMNs. This paper proposes a Layer 1 cluster-based network to solve the throughput bottleneck in the WMN. The proposed architecture is evaluated by several real world measurements. The obtained results are compared with the theory. The proposed solution shows a throughput improvement compared to a single-radio WMN and a multi-radio WMN using the CoMTaC channel allocation strategy.

This publication proposes a novel testing framework for the functional verification of decentralised services and applications in Peer-to-Peer (P2P)-connected Machine-to-Machine (M2M) networks. Besides presented challenges and requirements for testing within distributed environments, a concept for deriving and generating test cases based on a Test Description Language (TDL)-based approach is described and mapped to M2M applications.

P2P-based M2M application frameworks have several advantages, such as increased flexibility, efficiency and a lack of single point of failure as compared to centralised approaches. However, there are several security drawbacks which need to be addressed in order to provide the user a secure environment for the provision and usage of M2M applications. This publication presents different security issues inside P2P-based M2M application frameworks and evaluates P2P protocols based on security. In order to avoid different security attacks, the concept of trust and its importance are emphasized. Furthermore, a trust management system with special trust metric parameters is presented which considers the architecture of P2P-based M2M applications. Finally, blockchain principles are integrated for optimising the overall security in the system by improving data storage between peers, avoiding volatility of peers and ensuring correct working M2M applications.

This publication presents a novel concept for autonomous and decentralised M2M application service provision. The functional architecture of the approach is introduced as well as a detailed description of the system structure and process for application creation. Furthermore, this publication describes details about the proposed process for decentralised M2M application service management and formal description of M2M application services.