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Time-Sensitive Networking (TSN) has emerged as a key technology for ensuring reliable and deterministic communication in vehicular networks. However, the complexity of evaluating, configuring, and analyzing TSN mechanisms has hindered its widespread adoption. This paper introduces CONAN-TSN, an integrated toolchain designed to address these challenges by providing a comprehensive solution for the configuration, analysis, and evaluation of TSN networks. CONAN-TSN includes tools for traffic generation, traffic mapping, scheduling, and timing analysis, enabling seamless integration and practical implementation of TSN in vehicular systems. The toolchain’s effectiveness is demonstrated through its application to an industrial use case, showcasing its ability to enhance network schedulability and performance. The results highlight CONAN-TSN’s potential to bridge the gap between theoretical benefits and real-world deployment of TSN, offering a valuable resource for researchers and practitioners in the field.

Time-Sensitive Networking (TSN) is a set of standards with significant industrial impact potential, primarily due to its ability to integrate multiple traffic types with different requirements, offering great network flexibility. Among these traffic types, Audio-Video Bridging (AVB) stands out for its real-time guarantees and dynamic scheduling. In order to guarantee a specific set of AVB frames meet their timing requirements a Worst-Case Response Time Analysis (WCRTA) is essential. Unfortunately, current WCRTAs are often overly conservative, failing to guarantee schedulability for TSN systems operating even under low bandwidth conditions. This limits the practical usefulness of these analyses. Since TSN utilizes a multi-hop architecture, most WCRTAs analyze each link independently and then add the contributions. This compartmental analysis introduces pessimism, particularly when calculating the interference caused by other AVB frames with the same priority as the frame under analysis. In this paper, we address this issue by refining the Same-Priority Interference (SPI) calculation, leading to a significant improvement in the schedulability of WCRTAs and, consequently, the overall efficiency of TSN networks.

Time-Sensitive Networking (TSN) has become one of the most relevant communication networks in many application areas. Among several trafik classes supported by TSN networks, Audio-Video Bridging (AVB) traffk requires a Worst-Case Re­sponse Time Analysis (WCRTA) to ensure that AVB frames meet their time requirements. In this paper, we evaluate the existing WCRTAs that cover various features of TSN, including Scheduled Trafik (ST) interference and preemption. When considering the effect of the ST interference, we detect optimism problems in two of the existing WCRTAs, namely (i) the analysis based on the busy period calculation and (ii) the analysis based on the eligible interval. Therefore, we propose a new analysis including a new ST interference calculation that can extend the analysis based on the eligible interval approach. The new analysis covers the effect of the ST interference, the preemption by the ST traffic, and the multi-hop architecture. The resulting WCRTA, while safe, shows a significant improvement in terms of pessimism level compared to the existing analysis approaches relying on either the concept of busy period or the Network Calculus model. 

The new generation networks and systems are increasingly demanded to present higher capacities such as flexibility, adaptability, or real-time capabilities. In this context, Time-Sensitive Networking (TSN) standards provide Ethernet with functionalities capable of meeting these new demands. However, the adoption of TSN by the industry has been limited due to the high complexity of configuring and analyzing its various mechanisms. This thesis aims to address this issue by developing tools to facilitate the adoption of TSN in the industry. To this end, we have created tools to enable efficient and semi-automatic TSN configuration and analysis. These tools can efficiently configure TSN networks based on traffic characteristics while supporting legacy devices in case of migration or integration of legacy systems to TSN. Additionally, the analysis tools enable guaranteeing the compliance of the TSN configuration with the network requirements with reduced waste of resources.

Specifically, we have devised a mapping tool called LETRA to distribute the Ethernet-based traffic among the three basic types of TSN traffic, i.e. Scheduled Traffic (ST), Audio-Video Bridging Traffic (AVB), and Best-Effort Traffic (BE). Since ST requires traffic scheduling, we developed HERMES, a heuristic scheduler that generates efficient schedules in a fast manner. For AVB traffic, which requires some previous schedulability analysis to guarantee it meets its time requirements, we propose a new Worst-Case Response Time Analysis (WCRTA) which reduces the pessimism of previous approaches. Finally, regarding the support for the integration of legacy devices in TSN systems, we have developed mechanisms to avoid adverse consequences resulting from the lack of synchronization between legacy devices and TSN.

In order to facilitate the adoption of Time Sensitive Networking (TSN) by the industry, it is necessary to develop tools to integrate legacy systems with TSN. In this article, we propose a solution for the coexistence of different time domains from different legacy systems, each with its corresponding synchronization protocol, in a single TSN network. To this end, we experimentally identified the effects of replacing the communications subsystem of a legacy Ethernet-based network with TSN in terms of synchronization. Based on the results, we propose a solution called TALESS (TSN with Legacy End-Stations Synchronization). TALESS can identify the drift between the TSN communications subsystem and the integrated legacy devices (end-stations) and then modify the TSN schedule to adapt to the different time domains to avoid the effects of the lack of synchronization between them. We validate TALESS through both simulations and experiments on a prototype. We demonstrate that thanks to TALESS, legacy systems can synchronize through TSN and even improve features such as their reception jitter or their integrability with other legacy systems.

Novel production paradigms aim at increasing the efficiency and flexibility of production systems. Nonetheless, traditional industrial infrastructures lack the mechanisms needed to support these new paradigms. One of the main limiting factors is the architecture, which follows the automation pyramid in which subsystems are divided in layers depending on their functionalities. This allowed to meet the timing and dependability requirements of the production subsystems, however at the cost of limiting the exchange of information required to provide increased flexibility to the system. For this reason, in this paper we propose a new industrial architecture with a single network infrastructure to connect all the devices that conform to the industrial systems. On top of that, we design an Automatic Network Configurator to support the automatic configuration of the system. To assess the feasibility of our design and evaluate its performance, we implement the first instance of the architecture capable of supporting changes in the traffic requirements during run-time, i.e., without stopping or disrupting the system's operation. Furthermore, we use the implemented instance to measure the time required for reconfigurations.

New technologies present opportunities and challenges for industries. One major challenge is the ease, or even feasibility, of its adoption. The Time-Sensitive Networking (TSN) standards offer a range of features relevant to various applications and are key for the transition to Industry 4.0. These features include deterministic zero-jitter, low-latency data transmission, transmission of traffic with various levels of time-criticality on the same network, fault tolerance mechanisms, and advanced network management allowing dynamic reconfiguration.

This thesis aims to develop tools that enable the industry to adopt TSN easily and efficiently. Specifically, we create tools that facilitate the migration of legacy networks to TSN, enabling the preservation of most of the legacy systems and solutions while reducing costs and adoption time. Firstly, we introduce LETRA (Legacy Ethernet-based Traffic Mapping Tool), a tool for mapping Ethernet-based legacy traffic to the new TSN traffic classes. Secondly, we develop HERMES (Heuristic Multi-queue Scheduler), a heuristic Time-Triggered (TT) traffic scheduler that can meet the characteristics of legacy systems and provide quick results suitable for reconfiguration. Thirdly, we develop TALESS (TSN with Legacy End-Stations Synchronization), a mechanism to avoid adverse consequences caused by the lack of synchronization between legacy systems and TSN-based ones, as not all legacy systems need to support the TSN synchronization mechanisms. Finally, we improve Stream Reservation Protocol (SRP) to enhance Audio-Video Bridging (AVB) traffic configuration in terms of termination and consistency.

Uppfinningen av ångmaskinen i slutet av 1700-talet markerade början på en kontinuerlig och snabb process av automatisering och förbättring inom industrin, som tog ytterligare fart i och med införandet av datorstyrda maskiner och robotik i mitten av 1900-talet. Moderna fabriker och deras produkter är beroende av hundratals specialiserade processorer, inklusive sensorer, ställdon och styrenheter, som samarbetar för att utföra uppgifter och tillhandahålla tjänster. Dessa processorer är beroende av kommunikations-subsystem för att samordna och dela resurser. Dessa system, som vanligtvis kallas distribuerade system, omger oss och används av de flesta människor hela tiden. Exempel på distribuerade system finns i en mängd olika exempel, från moderna bilar till fabriker som producerar olika varor. I en bil finns det till exempel många olika sensorer och ställdon som hastighetsmätare, positionssensorer, bränsleinsprutare och tändspolar, som alla arbetar tillsammans för att se till att bilen fungerar säkert och effektivt, medan det i fabriker används robotarmar, transportband och andra anordningar för att automatisera produktionsprocessen och öka effektiviteten.

Den snabba utvecklingen av tekniken kan dock göra det svårt för företag att hålla jämna steg med de senaste verktygen och systemen, eftersom kostnaden för att införa tekniken kanske inte är kostnadseffektiv, inte bara på grund av att tekniken måste förvärvas, utan också på grund av de förändringar som införandet kräver i andra system som samarbetar. Till exempel skulle införandet av ett nytt kommunikations-subsystem kräva att alla enheter som använder det anpassas. Dessutom kräver uppgraderingen till nyare teknik ofta betydande resurser, inte bara ekonomiska utan även naturresurser. Detta kan leda till ökat avfall och ökade koldioxidutsläpp, vilket utgör en risk för miljön. Dessutom kan följderna av teknikuppgraderingar, till exempel bortskaffande av föråldrad utrustning och produktion av e-avfall, ha ytterligare miljöpåverkan.

I den här avhandlingen fokuserar vi på Time Sensitive Networking (TSN), en ny kommunikationsstandard med betydande fördelar för den framväxande tekniken. Även om TSN-tekniken ger många fördelar, bland annat högre kommunikationshastighet och lägre latenstider, saknar många nuvarande industrisystem mjuk- och hårdvarukraven för att stödja denna teknik. Målet med vår forskning är därför tvåfaldigt: för det första att förbättra TSN’s mekanismer för att göra den mer attraktiv för industrin och för det andra att utveckla verktyg som möjliggör en sömlös migration och integration av äldre system till TSN, så att slutstationerna kan utnyttja fördelarna med TSN utan att behöva byta ut eller uppgradera större delen av systemet. Detta tillvägagångssätt sparar värdefull tid och resurser och minskar det avfall som uppstår under processen.

In order to enable the adoption of Time Sensitive Networking (TSN) by the industry and be more environmentally sustainable, it is necessary to develop tools to integrate legacy systems with TSN. In this paper, we propose a solution for the coexistence of different time domains from different legacy systems with their corresponding synchronization protocols in a single TSN network. To this end, we experimentally identified the effects of replacing the communications subsystem of a legacy Ethernet-based network with TSN in terms of synchronization. Based on the results, we propose a solution called TALESS (TSN with Legacy End-Stations Synchronization). TALESS is able to identify the drift between the TSN communications subsystem and the integrated legacy devices (end-stations) and modify the TSN schedule to adapt to the different time domains to avoid the effects of the lack of synchronization between them. We validate TALESS through both simulations and experiments on a prototype. Thereby we demonstrate that thanks to TALESS, legacy systems are able to synchronize through TSN and even improve features such as their reception jitter or their integrability with other legacy systems.

Offline scheduling of Scheduled Traffic (ST) in Time-Sensitive Networks (TSN) without taking into account the quality of service of non-ST traffic, e.g., time-sensitive traffic such as Audio-Video Bridging (AVB) traffic, can potentially cause deadline misses for non-ST traffic. In this paper, we report our ongoing work to propose a solution that, regardless of the ST scheduling algorithm being used, can ensure meeting timing requirements for non-ST traffic. To do this, we define a frame called Guard Frame (GF) that will be scheduled together with all ST frames. We show that a proper design for the GFs will leave necessary porosity in the ST schedules to ensure that all non-ST traffic will meet their timing requirements.

The Time-Sensitive Networking (TSN) standards provide a toolbox of features to be utilized in various application domains.The core TSN features include deterministic zero-jitter and low-latency data transmission and transmitting traffic with various levels of time-criticality on the same network. To achieve a deterministic transmission, the TSN standards define a time-aware shaper that coordinates transmission of Time-Triggered (TT) traffic. In this paper, we tackle the challenge of scheduling the TT traffic and we propose a heuristic algorithm, called HERMES. Unlike the existing scheduling solutions, HERMES results in a significantly faster algorithm run-time and a high number of schedulable networks. HERMES can be configured in two modes of zero or relaxed reception jitter while using multiple TT queues to improve the schedulability. We compare HERMES with a constraint programming (CP)-based solution and we show that HERMES performs better than the CP-based solution if multiple TT queues are used, both with respect to algorithm run-time and schedulability of the networks.