Hello,
I would like to know how can the “resumeMAC-I” value of an unauthenticated emergency session with EIA0 and NEA0 can be calculated ? Tried to find a mention of this in the spec but only authenticated sessions with AS security contexts are described.
Best regards,
Karim
Admin note: this post was updated with image below.
If EN-DC is not configured, this IE indicates the integrity protection algorithm to be used for SRBs and DRBs, as specified in TS 33.501 [11].
The network does not configure nia0 for SRBs except for unauthenticated emergency sessions for unauthenticated UEs in LSM (limited service mode) and DRBs.
If EN-DC is not configured, this field is mandatory present, and the algorithm shall be the same for all bearers.
For EN-DC, this IE indicates the integrity protection algorithm to be used for SRBs, as specified in TS 33.501 [11].
The algorithms nia0-nia3 is identical to the LTE algorithms eia0-3. For EN-DC, the algorithms configured for SRBs using master key shall be the same as for all SRBs using master key and the algorithms configured for bearers using secondary key shall be the same as for all bearers using secondary key.
The network does not configure nia0 for SRB3