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| n |
UMTS supports
wide range of applications that posses
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different
quality of service (QoS) requirements.
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| n |
Applications
and services can be divided in different
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groups,
depending on QoS requirements. Four traffic
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classes can been
identified:
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n |
Conversational
class (very delay-sensitive traffic)
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n |
Streaming class
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n |
Interactive
class
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n |
Background class
(the most delay insensitive)
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| n |
Hence TCP
(Connection-oriented transport-layer ) is not
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always applied
- one may use also UDP (Connectionless
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transport-layer
protocol) - Why?
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