Which E2SM KPM version does srsRAN use?

[P4sca1]

I compiled FlexRIC using the -DKPM_VERSION=KPM_V3 flag. However, FlexRIC cashes when it tries to decode a RICIndication message from srsRAN gNodeB:

nearRT-RIC: /flexric/src/sm/kpm_sm/kpm_sm_v03.00/dec/kpm_dec_asn.c:186: kpm_dec_ind_msg_asn: Assertion `rval.code == RC_OK && "Are you sending data in ATS_ALIGNED_BASIC_PER syntax?"' failed.

I checked the gnb_e2ap.pcap file which indicates that KPM version 2 is used, instead of version 3.

Based on the following statement, I expected srsRAN to use version 3.

In addition, the repository provides two example Python-based xApps that allow requesting and monitoring E2 metrics from the gNB using all reporting styles (1-5) of the e2sm-kpm module (which was updated to version 3).
#471 (comment)

Also, am I correct that the version refers to the O-RAN specification of E2SM KPM? Which means that version 4 is already standardized?

[pgawlowicz]

Please check this patch: #567 (reply in thread)

[P4sca1]

I tried with the patch file and it is working now. It is important to start the xApp after the UE connects. Otherwise you get the following error:

nearRT-RIC: /flexric/src/sm/kpm_sm/kpm_sm_v03.00/dec/dec_asn_kpm_common/dec_meas_data.c:20: kpm_dec_meas_data_asn: Assertion `meas_data[i].meas_record_len >= 1 && meas_data[i].meas_record_len <= maxnoofMeasurementValue' failed.

Could you explain why Wireshark still shows KPM v2 in the RICIndication messages instead of v3?

[pgawlowicz]

Thanks for pointing this out, I will check. Probably, we send an empty RIC indication, while we should set the reported values to 0.

Not sure, about Wireshark. Which version do you use? You might try to compile from source.

[P4sca1]

I use version 4.2.4 on MacOS. Just wanted to make sure, that srsRAN sends version 3 packets.

[pgawlowicz]

Not sure why Wireshark shows KPM v2, it seems the dev version uses already v3 (check here). srsRAN also uses version 3.

Note that the in version 2, the Timestamp has 4 bytes (see here),
while in version 3, it has 8 bytes (see here)