The IEEE 802.1 Time-Sensitive Networking is a standard technology to provide deterministic routing or transmission of packets on standard Ethernet. By reserving resources for critical traffic, and applying various queuing and shaping techniques, TSN achieves zero congestion loss for critical data traffic. This, in turn, allows TSN to guarantee a worst-case end-to-end latency for critical data. TSN also provides ultra-reliability for data traffic via a data packet level reliability mechanism as well as protection against bandwidth violation, malfunctioning, malicious attacks, etc. TSN includes reliable time synchronization, a profile of IEEE 1588, which provides the basis for many other TSN functions.

1. USING AI FOR OPTIMAL TIME SENSITIVE NETWORKING IN
AVIONICS
Tom Jose
R&D
Mirabilis Design Inc.
Email: tjose@mirabilisdesign.com
Deepak Shankar
Founder
Mirabilis Design Inc.
Email: Deepak.shankar@mirabilisdesign.com
Mohini Yadav
R&D
Mirabilis Design Inc.
Email: myadav@mirabilisdesign.com
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2. Outline
•Introduction
•Research Methods
•Results
•Conclusion
•Future works
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3. Issues at hand
•Wiring adds up significant amount of weight to the avionics system
• Airbus A380 contains 500 Km of cables
•Current Communication architecture used cannot support the future requirements for data
bandwidth and connectivity
• 10 Gbps or higher for In Flight Entertainment system as backbone and for remote media loading
•Monitored data from different points in the network needs to be multiplexed into a single flight
data recorder.
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4. Solution
•Using Ethernet as backbone gives very high bandwidth for data
•But Ethernet is not deterministic and hence time critical packets might get delayed or even
worse, gets dropped
•By applying Time Sensitive Networking protocols (IEEE 802.1), a deterministic behaviour for time
critical applications can be observed in theory.
•Point to points connections wont be necessary here which in turn would reduces the wiring
substantially.
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5. Research Methods
•We used a System Level Modelling tool called VisualSim Architect for validating the solution.
• VisualSim Architect already had the IEEE 802.1 protocols added to their library and offered
customization to the users along with full visibility to code written
• This helped us to create different test cases and carry out the research much more efficiently
• VisualSim Architect already had template designs using 1553 bus and AFDX which made the comparison
between these easier.
•We tested the virtual prototypes under extreme stress and analysed the end to end latency
across different traffic classes, Buffer occupancy , credit plots etc
• Different traffic classes under study were:
• CDT – Very high priority and is time critical, Control data packets
• AVB – High priority but not as critical as CDT, Audio Video packets
• BE – Low priority, Best Effort packets
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6. Use case 1 – Simple load test
Virtual prototype
built in VisualSim
Latency plots for CDT, AVB and
BE
Buffer occupancy at the gateway
egress port
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7. Use case 2 – Avionics system
Virtual prototype
built in VisualSim DASC 2020

8. Use case 2 - Results
We can see that the CDT frames are no longer having
a deterministic behavior. This happens because of the
wrong slot configuration for the CDT frames.
It is evident that, configuring the Gate Control
List, idleSlope and bandwidth allocation are very
critical when dealing with real time traffic.
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9. Results after adding AI algorithm to
select right configuration
We can see that a deterministic response times for the
CDT frames were maintained by using AI
algorithms. .
We trained the algorithm with more than thousand
parameter combinations and the algorithm was able
to provide the optimal configurations for the system.
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10. Conclusion
•TSN standards when implemented without the optimal configuration, we obtained non deterministic
behavior for all traffic classes.
•While when implemented with the aid of AI, we observed deterministic behavior for the critical real time
traffic and even though non deterministic, a much stable response times from best effort frames were also
observed.
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11. Future works
•Future work aims at improving the safety island architecture for the avionics system.
•The presented use cases in this presentation will be discussed in future work, where faults will be injected
and performance will be analyzed.
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12. DASC 2020