Technical studies for operations with real-time communications in robotic missions

Robotic telepresence operations between earth and space are of high research value for science as they enable operators on ground to perform physical tasks in space without the need of human presence. Real-Time telepresence with haptic-feedback and stereoscopic imaging, however, poses new requirements to physical parameters of the communication channel like loss, delay and jitter as well as to the protocols spoken between the participants. To meet the new requirements, past robotic missions like ROKVISS chose to use specialized and dedicated communication channels while bypassing the established ground station network infrastructure. However, performing robotic and standard TM/TC operations in parallel was impossible because the Space Link could only be locked by either of the communication chains. For future missions, we present a setup that multiplexes robotic science data and standard TM/TC into one physical channel. Real-time requirements are met because the setup makes use of several FPGAs that forward UDP packets in synchronization with a common master clock. We present test results and test measurements of this technology and compare the proposed setup to a software based solution. Furthermore we present general approaches, tools and techniques for real-time related tasks. Finally we discuss the use of Space Link and Space Link Extension protocols in the communication chain and their impact on the real-time requirements. Operational aspects of the new setup and protocols are discussed as well

Evaluation of the IEC 61850 Communication Solutions

Initially, when the IEC 61850 standard was prepared, it was intended to be used within the limits of a substation for information exchange between devices. In the course of time and due to the standard’s advantages, its concepts are nowadays used as well in other application areas of the power utility system. The IEC 61850 is based to the maximum extent on other existing communication standards (IEC/IEEE/ISO/OSI), offering among others: visualization of the real applications through the ASCI interface, standardized messages to be exchanged (GOOSE, SV), one configuration language regardless of the device (IED) type/brand, and mapping to already implemented computing protocols (MMS, TCP/IP, Ethernet). The features mentioned above lead to cost reduction, reliability, and interoperability, making the IEC61850 the dominant standard for intra- and inter-substation communication. The parts 90-1 and 90-5 of the IEC 61850 standard concern the application of the tunneling and routing method in order to extend the communication beyond the substation’s limits. Although they establish the theoretical background, it can be mentioned a lack of information regarding real applications. So, the objective of this thesis was at first to establish the communication link which will allow the communication of devices belonging to different LANs and second, the acquiring of the round trip times from the exchanged messages. The experiments were conducted by a combination of software (Hamachi) and embedded platform (BeagleBone) pinging to each other first via tunneling and next via 4G mobile network. The acquired round-trip times were used to evaluate and compare the tunneling and the 4G routing method, estimating in parallel what are the perspectives of these methods to be used for inter-substation communication.fi=Opinnäytetyö kokotekstinä PDF-muodossa.|en=Thesis fulltext in PDF format.|sv=Lärdomsprov tillgängligt som fulltext i PDF-format

Delay measurements In live 5G cellular network

Abstract. 5G Network has many important properties, including increased bandwidth, increased data throughput, high reliability, high network density, and low latency. This thesis concentrate on the low latency attribute of the 5G Standalone (SA) mode and 5G Non-Standalone (NSA) mode. One of the most critical considerations in 5G is to have low latency network for various delay-sensitive applications, such as remote diagnostics and surgery in healthcare, self-driven cars, industrial factory automation, and live audio productions in the music industry. Therefore, 5G employs various retransmission algorithms and techniques to meet the low latency standards, a new frame structure with multiple subcarrier spacing (SCS) and time slots, and a new cloud-native core. For the low latency measurements, a test setup is built. A video is sent from the 5G User Equipment (UE) to the multimedia server deployed in the University of Oulu 5G test Network (5GTN) edge server. The University of Oulu 5GTN is operating both in NSA and SA modes. Delay is measured both for the downlink and the uplink direction with Qosium tool. When calculating millisecond-level transmission delays, clock synchronization is essential. Therefore, Precision Time Protocol daemon (PTPd) service is initiated on both the sending and receiving machines. The tests comply with the specifications developed at the University of Oulu 5GTN for both the SA and the NSA mode. When the delay measurement findings were compared between the two deployment modes, it was observed that the comparison was not appropriate. The primary reason for this is that in the 5GTN, the NSA and the SA have entirely different data routing paths and configurations. Additionally, the author did not have sufficient resources to make the required architectural changes

Analysis of Ethernet Powerlink network and development of a wireless extension based on the IEEE 802.11n WLAN

In questa tesi si analizza inizialmente Ethernet POWERLINK (EPL), una delle reti Ethernet Real-Time più popolari grazie alle sue caratteristiche e prestazioni. Viene poi proposta l'estensione wireless della rete POWERLINK basata sulla rete IEEE 802.11n (WLAN), con quest'ultima opportunamente ottimizzata per la comunicazione industriale attraverso l'algoritmo di dynamic rate adaptation RSIN

System-on-chip architecture for secure sub-microsecond synchronization systems

213 p.En esta tesis, se pretende abordar los problemas que conlleva la protección cibernética del Precision Time Protocol (PTP). Éste es uno de los protocolos de comunicación más sensibles de entre los considerados por los organismos de estandarización para su aplicación en las futuras Smart Grids o redes eléctricas inteligentes. PTP tiene como misión distribuir una referencia de tiempo desde un dispositivo maestro al resto de dispositivos esclavos, situados dentro de una misma red, de forma muy precisa. El protocolo es altamente vulnerable, ya que introduciendo tan sólo un error de tiempo de un microsegundo, pueden causarse graves problemas en las funciones de protección del equipamiento eléctrico, o incluso detener su funcionamiento. Para ello, se propone una nueva arquitectura System-on-Chip basada en dispositivos reconfigurables, con el objetivo de integrar el protocolo PTP y el conocido estándar de seguridad MACsec para redes Ethernet. La flexibilidad que los modernos dispositivos reconfigurables proporcionan, ha sido aprovechada para el diseño de una arquitectura en la que coexisten procesamiento hardware y software. Los resultados experimentales avalan la viabilidad de utilizar MACsec para proteger la sincronización en entornos industriales, sin degradar la precisión del protocolo

Spatial Statistical Data Fusion on Java-enabled Machines in Ubiquitous Sensor Networks

Wireless Sensor Networks (WSN) consist of small, cheap devices that have a combination of sensing, computing and communication capabilities. They must be able to communicate and process data efficiently using minimum amount of energy and cover an area of interest with the minimum number of sensors. This thesis proposes the use of techniques that were designed for Geostatistics and applies them to WSN field. Kriging and Cokriging interpolation that can be considered as Information Fusion algorithms were tested to prove the feasibility of the methods to increase coverage. To reduce energy consumption, a compression method that models correlations based on variograms was developed. A second challenge is to establish the communication to the external networks and to react to unexpected events. A demonstrator that uses commercial Java-enabled devices was implemented. It is able to perform remote monitoring, send SMS alarms and deploy remote updates

Moving target defense for securing smart grid communications: Architectural design, implementation and evaluation

Supervisory Control And Data Acquisition (SCADA) communications are often subjected to various kinds of sophisticated cyber-attacks which can have a serious impact on the Critical Infrastructure such as the power grid. Most of the time, the success of the attack is based on the static characteristics of the system, thereby enabling an easier profiling of the target system(s) by the adversary and consequently exploiting their limited resources. In this thesis, a novel approach to mitigate such static vulnerabilities is proposed by implementing a Moving Target Defense (MTD) strategy in a power grid SCADA environment, which leverages the existing communication network with an end-to-end IP Hopping technique among the trusted peer devices. This offers a proactive L3 layer network defense, minimizing IP-specific threats and thwarting worm propagation, APTs, etc., which utilize the cyber kill chain for attacking the system through the SCADA network. The main contribution of this thesis is to show how MTD concepts provide proactive defense against targeted cyber-attacks, and a dynamic attack surface to adversaries without compromising the availability of a SCADA system. Specifically, the thesis presents a brief overview of the different type of MTD designs, the proposed MTD architecture and its implementation with IP hopping technique over a Control Center–Substation network link along with a 3-way handshake protocol for synchronization on the Iowa State’s Power Cyber testbed. The thesis further investigates the delay and throughput characteristics of the entire system with and without the MTD to choose the best hopping rate for the given link. It also includes additional contributions for making the testbed scenarios more realistic to real world scenarios with multi-hop, multi-path WAN. Using that and studying a specific attack model, the thesis analyses the best ranges of IP address for different hopping rate and different number of interfaces. Finally, the thesis describes two case studies to explore and identify potential weaknesses of the proposed mechanism, and also experimentally validate the proposed mitigation alterations to resolve the discovered vulnerabilities. As part of future work, we plan to extend this work by optimizing the MTD algorithm to be more resilient by incorporating other techniques like network port mutation to further increase the attack complexity and cost

Wireless Data Logger – A Joint Use of Frequency Converter and Wireless Sensor Network

“Smart Industry” is a new unavoidable trend in vast varieties of industry fields. In the case of developing smart crane systems, cutting edge innovation and design is required. Many crane manufactures have expressed their strong interest in applying wireless technology to their crane products. Recent research achievements in wireless sensor node development have created technologically mature, cost effective solutions for many applications. When either monitoring or controlling the crane, one must have access to the frequency converter first. As for the purpose of analyzing the behavior of crane, the Wireless Sensor Network can be used to collect data from frequency converters. In this thesis, a wireless sensor network system was designed and developed in order to collect data from several frequency converters. The UWASA Node, a wireless sensor node designed by researchers from Aalto University and University of Vaasa, was implemented for establishing this wireless data logging network. As a result, the system has an ability of logging continuous data as well as the changes of data in user defined logging interval. Additionally, the reliability of the wireless transmission was investigated and possible solutions were presented.fi=Opinnäytetyö kokotekstinä PDF-muodossa.|en=Thesis fulltext in PDF format.|sv=Lärdomsprov tillgängligt som fulltext i PDF-format