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Cyber-physical systems (CPS) increasingly require real-time, high bandwidth data communication and processing. To address this, Time Sensitive Networking (TSN) provides latency-bounded data trans- mission at one or more gigabits-per-second throughput. However, it does not commonly connect directly to I/O devices, such as sensors and ac- tuators. In contrast, Universal Serial Bus (USB) is ubiquitous for device I/O, but has yet to be widely adopted for host-to-host networking. This paper considers the use of a common USB software stack for both device I/O and host-to-host communication. We compare against a sys- tem using USB for device I/O and TSN for host-level networking. Our findings show that a unified approach using USB results in reduced soft- ware complexity, simplified bus coordination, and more effective miti- gation of priority inversion when transferring data across multiple bus segments. Experiments show that end-to-end latency is within expected delay bounds, and is reduced if the same USB software stack is used for all communication with a given host. This suggests that bridging chal- lenges exist in current systems, which are solved by either extending a high-bandwidth bus such as TSN to support device I/O, or enhancing USB with improved networking capabilities.
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This content will become publicly available on November 5, 2026
Real-Time Bridging of I/O and Network Buses in Cyber-Physical Systems
Cyber-physical systems (CPS) increasingly require real-time, high bandwidth data communication and processing. To address this, Time Sensitive Networking (TSN) provides latency-bounded data transmission at one or more gigabits-per-second throughput. However, it does not commonly connect directly to I/O devices, such as sensors and actuators. In contrast, Universal Serial Bus (USB) is ubiquitous for device I/O, but has yet to be widely adopted for host-to-host networking. This paper considers the use of a common USB software stack for both device I/O and host-to-host communication. We compare against a system using USB for device I/O and TSN for host-level networking. Our findings show that a unified approach using USB results in reduced software complexity, simplified bus coordination, and more effective mitigation of priority inversion when transferring data across multiple bus segments. Experiments show that end-to-end latency is within expected delay bounds, and is reduced if the same USB software stack is used for all communication with a given host. This suggests that bridging challenges exist in current systems, which are solved by either extending a high-bandwidth bus such as TSN to support device I/O, or enhancing USB with improved networking capabilities.
more »
« less
- Award ID(s):
- 2007707
- PAR ID:
- 10649899
- Publisher / Repository:
- Proceedings of the 33rd International Conference on Real-Time Networks and Systems (RTNS)
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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