Packet Switching (basics)
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Packet Switching (basics)
description
Packet Switching (basics). Crossbar scheduling: “ Take-a-ticket ”. HOL Probability that none of the N input ports chooses a given output port is (1-1/N) N ≈ 37% So, max throughput of this switch is: 63%. Avoid HOL-blocking with multiple input queues (one per output port). - PowerPoint PPT Presentation
Transcript of Packet Switching (basics)
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Packet Switching (basics)
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Crossbar scheduling: “Take-a-ticket”
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HOLProbability that none of the N input ports
chooses a given output port is (1-1/N)N ≈ 37%So, max throughput of this switch is: 63%
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Avoid HOL-blocking with multiple input queues (one per output port)
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PIM: Parallel Iterative Matching
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iSLIP (avoids randomization of PIM)
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iSLIP (cont’)
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Multistage switching
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Blocking vs non-blocking switching networks
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Blocking vs non-blocking switching networks
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Clos network (N, n, k):Non-blocking if k ≥2n-1 (Prove this!)
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Clos network (N,n,k=2n-1):Prove that min number of crosspoints = 5.6N√N
(for n= √ (N/2)
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Banyan networksand
the self-routing property
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Benes network
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