... | ... | @@ -210,33 +210,37 @@ The enhancements to current IEEE 802.1AS include |
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- proposed to exchange Tx and Rx (manually or automatically),
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[see](http://www.ieee802.org/1/files/public/docs2011/as-huang-compensation-for-physical-line-asymmetry-0311.pdf)
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### P802.1Qbv : Enhancements for Scheduled Traffic
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### P802.1Qbv : Enhancements for Scheduled Traffic - Time Aware Shaper
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- to provide lower network delays
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- defines ways for bridges and end stations to schedule the
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transmission of frames based on timing derived from IEEE Std 802.1AS
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- Time Aware (Blocking/De-blocking) Shaper in bridges and end
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stations, see
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[pages 30](http://www.ieee802.org/1/files/public/docs2011/new-pannell-latency-options-0311-v1.pdf),
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best used with preemption
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[pages 30](http://www.ieee802.org/1/files/public/docs2011/new-pannell-latency-options-0311-v1.pdf)
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- creates a time window within which only time-sensitive traffic is
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sent - enables to ensure that time-sensitive traffic does not
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interfere with best-effort traffic (the former does not need to wait
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for the latter to be finished sending)
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- best used with preemption
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([page 15](http://www.ieee802.org/1/files/public/docs2011/new-avb-boiger-meeting-gen2-latency-req-1111.pdf))
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- preemption enables to decrease the bandwidth overhead
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([page 11](http://www.ieee802.org/1/files/public/docs2012/new-avb-nfinn-preempt-advantage-0112-v02.pdf))
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### P802.1Qbu : Frame Preemption
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- to provide lower network delays
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- allows very time-sensitive packets to interrupt a normal best-effort
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packet being transmitted on an egress port and then resume it once
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the time-sensitive packet has been transmitted
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- [here](pages)
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30":http://www.ieee802.org/1/files/public/docs2011/new-pannell-latency-options-0311-v1.pdf
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- most efficient when used with Time Aware Blocking Shaper (would be
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defined in P802.Qbv),
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the time-sensitive packet has been
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transmitted
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- [pages 30](http://www.ieee802.org/1/files/public/docs2011/new-pannell-latency-options-0311-v1.pdf)
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- most efficient when used with Time Aware Shaper (would be defined in
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P802.Qbv),
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[page 15](http://www.ieee802.org/1/files/public/docs2011/new-avb-boiger-meeting-gen2-latency-req-1111.pdf)
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and page
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11":http://www.ieee802.org/1/files/public/docs2012/new-avb-nfinn-preempt-advantage-0112-v02.pdf
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-
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### New topology resolution (probably enhancement of IEEE 802.1Qat-2010)
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- aims at providing multiple paths for both redundancy and enhanced
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