Revision 18bf9bb1
Added by osmith about 4 years ago
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well. |
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== Recommendations for Real-World Implementations |
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=== ATT = 0 |
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=== BCCH SI3: ATT = 0 |
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When changing from one pseudonymous IMSI to the next, it is important that the |
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ME does not detach from the network. Otherwise it would be trivial for an |
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attacker to correlate the detach with the attach of the same ME with the next |
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pseudonymous IMSI. |
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This is controlled with the ATT flag in the SYSTEM INFORMATION TYPE 3 (SI3) |
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message on the Broadcast Control Channel (BCCH), see 3GPP TS 44.018 Section |
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10.5.2.11. It must be set to 0. |
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// FIXME: verify how it set with operators in germany (OS#4404) |
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=== End to End Encryption of SMS |
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[[warn-no-imsi-change]] |
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=== Warning the User if the IMSI Does Not Change |
Also available in: Unified diff
spec: ATT = 0