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EUTRAN LTE Mobile Networks

Working with LTE MAC traces in Wireshark

Using Wireshark to view and analyze MAC layer LTE traffic

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EPC EUTRAN LTE Mobile Networks Notes RF

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

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 […]

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LTE Mobile Networks RF RFCs & Standards Security

LTE (4G) – Ciphering & Integrity of Messages

We’ve already touched on how subscribers are authenticated to the network, how the network is authenticated to subscribers. Those functions are done “in the clear” meaning anyone listening can get a copy of the data transmitted, and responses could be spoofed or faked. To prevent this, we want to ensure the data is ciphered (encrypted) […]

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EUTRAN LTE Mobile Networks Notes RF

IMTx: NET02x (4G Network Essentials) – Radio Interface – 5. RLC Protocol

These are my lecture notes from IMT’s NET02x (4G Network Essentials) course, I thought I’d post them here as they may be useful to someone. You can find my complete notes here. As we just discussed the MAC layer multiplexes streams from the RLC layer. This allows mutliple streams of data to share the same […]

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EUTRAN LTE Mobile Networks Notes RF

IMTx: NET02x (4G Network Essentials) – Radio Interface – 4. Transmission Reliability in Radio

These are my lecture notes from IMT’s NET02x (4G Network Essentials) course, I thought I’d post them here as they may be useful to someone. You can find my complete notes here. Radio is always subject to interference, we talked before about how coding is used on the physical layer to try and correct these […]