Impact on credit freeze before gate closing in CBS and GCL integration into TSN

Hugo Daigmorte (1) , Marc Boyer (2)

1 DISC - Département d'Ingénierie des Systèmes Complexes
2 DTIS, ONERA, Université de Toulouse [Toulouse]

The Time Sensitive Networking (TSN) task group has added a set of mechanisms to Ethernet in order to provide a real-time network. In particular, the output port scheduling based on a Credit-Based Shaper (CBS) algorithm, that was introduced formerly by the Audio-Video Bridging (AVB) task group, has been enhanced with a time driven Gate Control List (GCL). This implies some update in the credit evolution rules, and several solutions may exist. In this paper, we compare the solution used in the standard with another one used in most papers, and also with a third one, designed as a trade-off between the two others. The comparison is first done on some hand-made examples, showing some credit overflow and unfairness potential problems. Then, simulations are done on a single switch with 3 CBS queues.

Mots clés: Real Time Network; Time Sensitive Networking; TSN

Domaines: Systèmes embarqués

Hugo Daigmorte, Marc Boyer. Impact on credit freeze before gate closing in CBS and GCL integration into TSN. 27th International Conference on Real-Time Networks and Systems (RTNS 2019), Nov 2019, Toulouse, France. pp.1-10. ⟨hal-02335619⟩