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| n |
NSS
is the main component of the public mobile network
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GSM
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– |
switching,
mobility management, interconnection to other
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networks,
system control
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| n |
Components
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Mobile
Services Switching Center (MSC)
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controls
all connections via a separated network to/from a mobile
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terminal
within the domain of the MSC - several BSC can belong
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to a
MSC
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Databases
(important: scalability, high capacity, low delay)
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n |
Home
Location Register (HLR)
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central
master database containing user data, permanent and semi-
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permanent
data of all subscribers assigned to the HLR (one provider
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can
have several HLRs)
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n |
Visitor
Location Register (VLR)
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local
database for a subset of user data, including data about all user
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currently
in the domain of the VLR
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