... | @@ -280,6 +280,26 @@ The enhancements to current IEEE 802.1AS include |
... | @@ -280,6 +280,26 @@ The enhancements to current IEEE 802.1AS include |
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## **AVB *Gen2* vs. White Rabbit**
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## **AVB *Gen2* vs. White Rabbit**
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### Requrements
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- Ultra-low latency for critical traffic
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- CERN
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- maximum latency: 1000us over ~5 bridge hops @ 1Gbps
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([page 10](https://www.ohwr.org/project/white-rabbit/uploads/1244844e3c3cf850fad84e575f3b3f61/wrCernControlAndTiming.v1.1.pdf))
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- guaranteed latency over tree-like topology
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([page 19](https://www.ohwr.org/project/white-rabbit/uploads/1244844e3c3cf850fad84e575f3b3f61/wrCernControlAndTiming.v1.1.pdf))
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- main network characteristics: \_2000 end stations, links of
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max 10km, max network span: 10km
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- traffic characteristics: "control data" size (payload):
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burst of 4 x 300 bytes
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([FEC](https://www.ohwr.org/project/white-rabbit/uploads/ff98688542afbe36e9f11877ba4c5f1a/ICALEPCS2011_poster.pdf)),
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~8 "control streams" (defined in VLANs, see
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[page 7](https://www.ohwr.org/project/white-rabbit/uploads/1244844e3c3cf850fad84e575f3b3f61/wrCernControlAndTiming.v1.1.pdf))
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sent every 1000us, "normal data" size (payload): ~1500 bytes
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<!-- end list -->
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- preemption
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- preemption
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<!-- end list -->
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<!-- end list -->
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