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| n |
Problems
with New metric
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under
low load, static factors dominated cost; worked OK
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under
high load, congested links had very high costs; packets
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oscillated
between congested and idle links
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range
of costs too large; preferred path of 126 lightly loaded
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56Kbps
links to a 1-hop 9.6Kbps path
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| n |
Revised
ARPANET metric
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replaced
delay measurement with link utilization
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compressed
dynamic range
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n |
highly
loaded link never has a cost more than 3 times its idle cost
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n |
most
expensive link only 7 times the cost of the least expensive
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n |
high-speed
satellite link more attractive than low-speed terrestrial link
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n |
cost
is a function of link utilization only at moderate to high loads.
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