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technische universiteit eindhoven

Problem 16: Design-space Exploration

Jeroen Voeten, Bart Theelen

Eindhoven University of Technology

Embedded Systems Institute

J.P.M.Voeten@tue.nl

Packet-switch case

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technische universiteit eindhoven

I/O Bus

Links

NetworkAdaptors

BusArbiter

I/O Ports

Packet switch

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technische universiteit eindhoven

Specification A second-generation 4 x 4 switch

Fixed-sized packets of 25 bytes long

Link bandwidth 10 Mbps in both input and output direction (50.000 packets per second)

Incoming traffic per link: idle periods alternated with bursts

packets in a burst have the same destination

packet destination is homogeneously distributed (1 … 4)

traffic stream characterized with load and average burst-size parameters; average burst-size is 10 packets

Packets entering a full queue are lost

Bus-arbitration: round robin (one complete packet per turn & work-conserving)

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technische universiteit eindhoven

Minimize Total buffer capacities (in packets)

Bus capacity (in packets per second)

Maximize load that can be dealt with

Requirements Average packet delay at most 200 s

Packet loss probability at most 0.01

Optimization Criteria and Requirements