... | ... | @@ -215,16 +215,27 @@ The enhancements to current IEEE 802.1AS include |
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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 Shaper, 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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([page 15](http://www.ieee802.org/1/files/public/docs2011/new-avb-boiger-meeting-gen2-latency-req-1111.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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- b
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- c
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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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[page 15](http://www.ieee802.org/1/files/public/docs2011/new-avb-boiger-meeting-gen2-latency-req-1111.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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... | ... | @@ -250,6 +261,16 @@ The enhancements to current IEEE 802.1AS include |
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## **AVB *Gen2* vs. White Rabbit**
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- preemption
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<!-- end list -->
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- Time Aware Blocking Shaper:
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- some problem when cut-through for non-critical traffic -- we
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don't know the size of the frame
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<!-- end list -->
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- fault tolerance / isolation
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- we want to use VLANs to isolate different network and limit a
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propagation of destruction by mis-behaving node/switch
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