- according to 5.3.7.4 of TS 38.331: 1> re-establish RLC for SRB1;
- gNB:
1) re-establish RLC for SRB1 in nr_rlc_update_id
2) re-establish RLC for remaining RBs concurrently with RRCReconfiguration
issue: gNB) in nr_rlc_update_id the gNB is re-establishing RLC for all
RBs at the same time when receiving RRCReestablishmentRequest
from UE
UE) according to the specs, the UE is re-establishing RLC for
SRB1 with RRCReestablishmentRequest the other RBs are
re-established during RRCReconfiguration (in our case in
nr_rrc_ue_process_RadioBearerConfig) when receiving
reestablishRLC IE in rlc_BearerToAddModList
RLC TX) this leads to RLC counters mismatch after re-establishment:
control PDUs discarded until max nb of retx is reached
and then UL failure occurs
- remove PDCP reestablishment for DRBs from RRCReestablishment message generation
- do PDCP reestablishment and CUUP notification calls after reception or RRCReestablishmentComplete
- this is necessary to make it consistent with the RRCReconfiguration message that contains
RadioBearerConfig with the list of bearers to add/release
which is followed by PDCP re-establishment at UE
- SRB1 shall be re-established at the time of RRCReestablishmentRequest
according to 5.3.7.4 of 3GPP TS 38.331
- SRB2 shall be re-established when creating srb-ToAddModList
according to 5.3.5.6.3 of 3GPP TS 38.331
- adding a new test case
- the test case simulate a DL radio channel with noise and runs Iperf test with such channel conditions
- use CustomCommand class to send commands to a Telnet server
- switched from netcat’s unsupported -N option (OpenBSD) to --send-only (Ncat 7.94) for compatibility with CI
re-sync CI test in F1 RFSIM
- to be used in the future, for CI of RRCReestablishment in RFSIM
- adding four new test cases (040021, 040022, 040023, 040023) to the RFSIM F1 configuration
- the test cases simulate a disruption of the radio channel, verify UE sync loss and resync
and restore the original channel conditions
- use CustomCommand class to send commands to a Telnet server
temp xml
- this change simplifies the enum definition and makes it easier
to add, remove, or modify states in the future
- the states are now defined in the NR_UE_L2_STATES macro,
and the enum members are generated automatically from this macro
- PDCP reestablishment on CUCP (DRBs) triggering Bearer Context Modification procedures over E1
- Performing PDCP reestablishment for requested DRBs on CUUP
- Introduced function to notify re-establishment to CU-UP
- removed call to PDCP reestablishment for the DRBs on CUCP (it's done on CUUP)
cuup_notify_reestablishment:
- to fetch PDU session to setup in E1 following logic as in e1_send_bearer_updates
- fill bearer context modification request with stored F1-U tunnel information
during E1 reestablishment, otherwise it would initialized to 0 by default
- update GTP tunnel with the stored configuration after E1 reestablishment
- many structs and definitions are overlapping between the two different E1 procedures
- introduced naming specific to E1 Bearer Context Modification to improve readability
- grouped SDAP and PDCP configuration IEs for better reusability and readability
- introduced functions to set and get default PDCP config (DRBs and Bearer Contexts)
find_or_next_pdu_session:
- find_or_next_pdu_session refers to the E1 Bearer Context Modification Request
-- therefore it has to return pdu_session_to_mod_t* and takes in input e1ap_bearer_mod_req_t *
see !MR2545 for more context
- according to specs, in NR there are 4 SRBs
- in OAI the relevant define is used in the RRC procedures
- this commit harmonizes code by removing redundancy
- triggered by RRC reconfiguration events according to clause 5.3.5.6.5 of TS 38.331
- This procedure does QoS flow to DRB mapping according to clause 5.3.1 of TS 37.324
- QoS flows to DRBs to be released are also handled
- deleted: ../../../executables/rfsim.c
- removed unused command line options to set SINR and SNR
- removed unused functions to get SINR and SNR
- removed unused RFSIM struct members
- CU-CP replying to the CU-UP with a Setup Failure message in case of unsuccessfull E1 Setup Request
- message is decoded by the CU-UP, and stops the process
Guido Casati