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| n |
Circuit-switched
operation
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– |
uplink
and downlink channels allocated for a user for entire call
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period
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n |
busy
user uses only one direction of link (typically), so 50% of
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resources
are wasted
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– |
user
pays for the connection time, not for the amount of data
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n |
bad
connections - more retransmissions - make more money for
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operator
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n |
pay
even if no data is transmitted
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– |
connection
establishment time: 20-25 seconds
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n |
bad
for short-lived transactions
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– |
capacity:
9.6 kbps (channel coding designed for worst-case radio
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situation)
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connections:
to any modem service in PSTN
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