Deterministic TCP Traffic Shaping for Backend Protection in Connected VehicleseIntroduction Thesis work is an excellent way to get closer to TRATON and build relationships for the future. Many of today's employees began their TRATON career with their degree project. Our team is responsible for developing and maintaining the Connectivity Platform, a brand-agnostic solution that enables unified communication and connectivity across trucks of all TRATON brands. We ensure that vehicles can reliably interact with backend systems and digital services, regardless of brand. We work with an agile, product-oriented mindset, owning the platform end-to-end and driving its evolution to meet future needs. Our work spans multiple domains, including connectivity, hardware integration, security, and diagnostics, while ensuring scalability and high availability for millions of connected vehicles worldwide. Background Many connected vehicles communicate with shared backend services for telemetry, remote diagnostics, software updates, cloud services, navigation, and other applications. These services often share the same cellular connection and onboard communication infrastructure. Traffic loads may vary across services and vehicles, resulting in changing bandwidth demand and potentially affecting latency, queue lengths, transmission rates, and communication predictability. This thesis aims to design, implement, and evaluate an onboard TCP traffic-shaping system for connected vehicles, using predefined rules for shaping and scheduling. These rules provide deterministic traffic control, while end-to-end latency and throughput remain subject to variable cellular conditions. The system is intended to help protect shared backend services from excessive outbound traffic generated by connected vehicles. It uses a TCP proxy to shape encrypted traffic according to configurable, service-specific policies designed to accommodate expected traffic while limiting disproportionate bandwidth use by service clients. When application demand exceeds the configured shaping limits or available network capacity, data may accumulate in bounded buffers. Forwarding is regulated according to the selected policy, and TCP backpressure is used to constrain sending applications. This provides a basis for studying how different traffic policies influence throughput, latency, buffer occupancy, and service quality under challenging network conditions. Historical traffic data may be used to support the configuration, scenario selection, and evaluation of the selected traffic-shaping model. Objective The objective of this thesis is to design, implement, and evaluate a deterministic TCP traffic-shaping system intended for onboard use in connected vehicles. The system will regulate variable application demand and help protect shared backend services from excessive traffic. The proposed system will include: A transparent TCP proxy that relays TLS-encrypted byte streams without terminating TLS, using se
