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| n |
Basic service
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n |
Bearer service
(local loop access): analog (/ISDN)
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| n |
Value-added
services (telephonist-originated) services as
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n |
directory
inquiry (118)
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n |
weather, stock
exchange, ticket reservation ...
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| n |
Supplementary
services (Intelligent Terminal (IN)
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implementation)
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n |
distributed
supplementary as ‘call forwarding
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unconditional’,
‘call waiting’, ‘queuing’ ...
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n |
centralized
supplementary services (IN) use specialized
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routing &
charging as VPN, credit card calls, free phone
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(receiver
pays), universal access number (connected
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automatically to
the nearest office), ...
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