... | ... | @@ -309,16 +309,30 @@ The enhancements to current IEEE 802.1AS include |
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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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- Reliability seamless redundancy (synchronization-wise and critical
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data-wise)
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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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- using phase detection (DDMTD) to enhance HW-timestamping precision
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to picosecond level
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- auto-calibration of link asymmetry (single fiber and DDMTD phase
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detection)
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- support of network redundancy and seamless (no time) reconfiguration
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<!-- end list -->
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*AVBg2 vs. WR:**
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The main difference is the usage of SyncE and single fiber in WR. AVBg2
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bridges will have to be time aware, so will probably syntonize to
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grandmaster's frequency using Sync Messages and will need to synchronize
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to grandmaster, like WR (AVBg1 bridges are transparent and syntonize
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optionally). The efforts to support network redundancy and speed-up
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reconfiguration seem to be inline in WR and AVB.
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### Reliability
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### Latency:
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- preemption
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