After a reestablishment, the PDCP sequence number counters have to be
reset. Implement an API to allow the RRC to reset the sequence numbers
for a particular UE in the case of reestablishment
The RRC gives its own RRC UE ID. It won't intervene if DUs assign the same RNTI to different UEs: it simply does not care what the DUs do with the RNTI.
- Use the same CU-UP in E1 as in CU-CP: we don't have a separate entity
to allocate IDs, and we just use the same as the CU-CP
- Correct gNB CU-UP/CP UE IDs in E1AP message types to 32bit
- Set CU UP UE ID explicitly for clarity
- Remove RNTI from E1 messages, E1 does not know what an RNTI is
- The CU/DU UE ID is used in DL RRC Message Transfer
- Note: The CU UE ID currently is still the RNTI
- on every DL RRC Message, the DU verifies that the UE exists
- Refactor RRC: common function to forward protected SRB PDUs
The RRC uses gNB_ue_ngap_id as its primary ID; the following commits
will introduce the usage of the (F1) gNB CU UE ID. This commits renames
the gNB_ue_ngap_id to rrc_ue_id to better reflect its usage as the RRC's
primary UE ID.
It will be used as the NGAP and F1 (CU) UE IDs.
The RLC tests were not compiling because of the include of
openair2/RRC/NR/rrc_gNB_radio_bearers.h
by
openair2/LAYER2/nr_rlc/nr_rlc_entity.h
which does not seem correct/necessary to start with.
The only thing needed by nr_rlc_entity.h from rrc_gNB_radio_bearers.h
is MAX_DRBS_PER_UE which can be defined in common/platform_constants.h
like NGAP_MAX_PDU_SESSION.
For the reestablishment, the SRB2 in the RRC reconfiguration
following the reestablishment needs to include ReestablishPDCP true.
We were not sending that. In this commit, I add a parameter to
add that parameter on demand. There might be a better solution.
CMake now takes the option ASN1C_EXEC to select an asn1c to use for
compilation. For instance, run with
cmake .. -GNinja -DASN1C_EXEC=/opt/asn1c/bin/asn1c
or
./build_oai --cmake-opt -DASN1C_EXEC=/opt/asn1c/bin/asn1c
to select the alternative asn1c. For instance, this is important for the
CI to allow to build multiple versions of OAI in parallel that might use
different commits of OAI.
Further, this patch introduces functionality to check for the support of
asn1c options that we require, and alerts the user if they are missing,
alongside a message of how to resolve the problem.
We don't work much on asn1c. The version we use has several bugs.
There is an active community out there that fixes bugs and improves
asn1c. Let's use their version.
Robert Schmidt