Predictable data transport : a delay and energy perspective

Cyber-physical systems extend the digital revolution to almost every aspect of our lives by bridging the gap between the digital and physical worlds. These systems demand unprecedented timeliness and reliability guarantees that the current operating and network systems do not provide. Transport layer protocols are the direct communication interface for the application layer and, hence, are key to providing end-to-end guarantees to the application. This thesis addresses how transport layer protocols should be designed to support cyber-physical systems. A clear candidate is the Predictably Reliable Real-time Transport (PRRT) protocol, which provides the application with a predictably reliable service within the specified time budget. This thesis makes original contributions to PRRT’s error control function, which decides when and how much redundancy must be transmitted to meet the reliability and delay requirements of the application. The main contributions of this thesis are threefold: i) the SHARQ algorithm, which obtains the optimal error control configuration meeting the application constraints, and has been optimized to achieve predictably quick reactions to channel changes, ii) the DeepSHARQ algorithm, which leverages neural networks and a novel output regularization method to bring this predictability to resource-constrained devices, and iii) a systematic analysis of binary codes as an energy-efficient alternative for error coding at the transport layer, questioning the long-held belief that Vandermonde codes are a more suitable alternative due to their better error correction capabilities. ; Cyber-physikalische Systeme erweitern die digitale Revolution auf nahezu jeden Aspekt unseres Lebens, indem sie die Kluft zwischen der digitalen und physikalischen Welt überbrücken. Diese Systeme erfordern beispiellose zeitliche und beispiellose Garantien bzgl. Zeit-Verbrauch und Fehlerraten, die das aktuelle Betriebssystem und das Netzwerk nicht bieten. Transport-Protokolle sind die direkte Kommunikationsschnittstelle ...