The job of moving data round a network, with the objectives of maximum throughput, minimum delay, and minimum cost, is very similar to the job of moving components and subassemblies round a factory. Manufacturing has been through a revolution over the last 50 years, and modern manufacturing uses concepts and techniques that would have been thought crazy 50 years ago. Even with recent advances, computer networks are still more like the old production lines. So if 1355 seems crazy to you now, this analogy might help to explain why 1355, or something very much like it, is utterly inevitable.
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Old production line |
Modern manufacturing |
IEEE 1355 |
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Bottlenecks |
Spare or flexible capacity to eliminate bottlenecks |
Multiple paths and adaptive routing to eliminate bottlenecks, provide fault tolerance |
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Rigid production lines |
Flexible manufacturing |
Flexible encapsulation of other protocols, |
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Quality doesn't matter/repair if faulty |
Quality is paramount, Zero defects |
Reliable links, |
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Don't change it |
Continuous improvement |
Adding nodes and links continuously improves the network throughput |
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Lead time is irrelevant |
Just-In-Time because delay reduces quality, reduces customer service, and reduces throughput |
Worm-hole routing and flow-control minimise delay |
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Long conveyor belt |
Many small, independent, cells |
Many independent links |
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Large batch sizes |
Small batches, in trays, preferably one unit per tray |
Small packets, appropriate for the application |
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"Push" components onto the line |
When a tray is used, the tray goes back as an order to "pull" more components |
Feedback flow-control "pulls" data when there is space for it |
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Long change-over time |
Very fast tool-change |
Fast, widely distributed, independent, arbitrations; |
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Environment does not matter |
Waste of any kind is damaging to the environment (as well as profit) |
Eliminate wasted data from buffer overflow, eliminate wasted power driving unnecessary wires, eliminate unnecessary RF pollution |
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Inventory is asset |
Inventory is liability |
Minimise data buffers |
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Make 50% profit margin once per year |
Make 20% profit margin 10 times per year |
1/5th the link speed in a switched network can offer 20 times the overall throughput of a bus or ring |