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| n |
proposal
two
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use
external Packet Data Network
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IWF1
incorporates IWF2 function - concentrates packets and performs
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protocol
conversions
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IWF1
located in BSS (Base Station Sub-system) requires many
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access
units to external network
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IWF1
located in MSC requires functions to route packets to proper
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BSC
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router
able to access HLR (and VLR if IWF1 is located in BSS)
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required
in external PDN
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| n |
proposal
three
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use
dedicated GPRS packet network from IWF1 to IWF2
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– |
protocol
routers interface with HLR (and VLR if IWF1 is located in
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BSS)
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packet
routing information could be cached at routers to avoid HLR
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check
for individual packets
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