... | ... | @@ -298,16 +298,25 @@ The enhancements to current IEEE 802.1AS include |
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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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- GSI
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- maximum latency: 100us over ~? bridge hops @ 1Gbps
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- GSI (not necessarily up-to-date)
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- maximum latency: 100us over ~4 bridge hops @ 1Gbps
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- guaranteed latency over tree-like topology
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- main network characteristics: ~2000 end stations, links of
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max 2km, max network span: 2km
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- traffic characteristics: "control data" size (payload):
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200-500 bytes (encoded into several frames of size 150-300
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bytes and sent in burst,
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200-500 bytes (encoded into 4 frames of size 150-300 bytes
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and sent in burst,
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[FEC](https://www.ohwr.org/project/white-rabbit/uploads/ff98688542afbe36e9f11877ba4c5f1a/ICALEPCS2011_poster.pdf)),
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sent every 100us, "normal data" size (payload): ~1500 bytes
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- Synchronization: sub-nanosecond in the entire network
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### Timing and Synchronization
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- profile/extension of PTP: WRPTP
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- requires physical syntonization using Synchronous Ethernet
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- using phase detection to enhance HW-timestamping precision to
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picosecond level
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- support of network redundancy and seamless (no time) reconfiguration
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