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EPC EUTRAN LTE Mobile Networks Notes RF SDM

LTE (4G) – TMSI & GUTI

We’ve already touched on how subscribers are authenticated to the network, how the network is authenticated to subscribers and how the key hierarchy works for encryption of user data and control plane data. If the IMSI was broadcast in the clear over the air, anyone listening would have the unique identifier of the subscriber nearby […]

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LTE Mobile Networks RF RFCs & Standards Security SIM Cards

LTE (4G) – EUTRAN – Key Distribution and Hierarchy

We’ve talked a bit in the past few posts about keys, K and all it’s derivatives, such as Kenc, Kint, etc. Each of these is derived from our single secret key K, known only to the HSS and the USIM. To minimise the load on the HSS, the HSS transfers some of the key management […]