14 lines
450 B
Plaintext
14 lines
450 B
Plaintext
FOSS in the Mobile World
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GSM Network Architecture
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GSM is a bit-synchronous network
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it draws many analogies from ISDN and SDN
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layer 2 modelled after Q.921 / LAPD
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call signalling modelled Q.931
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but: many more protocols for mobility management, radio resources, ...
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like all traditional Telco protocols: Intelligence in the network, not in the end nodes.
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GSM is a TDMA "nightmare"
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e.g. you never know from/for whom data is without the timing context
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