srsRAN control capabilities via E2/FlexRIC

[alektoja]

Hi,
I’m integrating srsRAN Project (gNB/DU) with a FlexRIC near-RT RIC. E2 is up and xApps connect. I see E2SM-RC on the DU and Action ID 6 “Slice-level PRB quota” mapping to du_mac_sched_control_config (files e2sm_rc_control_action_du_executor.*).

A few quick questions:

1. Which E2SM-RC control actions/styles are supported today on DU/CU? Is Action 6 the only one available out-of-the-box?
2. Is per-UE control (e.g., UL/DL MCS cap, P0_PUSCH, OLLA offsets) supported via RC or MAC_SM? Sending “MAC control: pusch_mcs” from FlexRIC gets CONTROL-ACK, but gNB MCS doesn’t change—does that mean MAC_SM control isn’t implemented?
3. If not, what’s the recommended extension point? Would adding an RC action (CRNTI, UL_MCS_MAX) → DU/MAC → clamp in ue_link_adaptation_controller be aligned with the project?

Setup: srsRAN Project (latest commit), FlexRIC RIC with KPM + RC; sample xApps from examples/xApp/c/control (e.g., xapp_oran_slice_ctrl).

[pgawlowicz]

Hi,

1. Currently, we support:

• CONTROL Service Style 3: Connected Mode Mobility, Control Action ID 1: Handover Control in CU.
• CONTROL Service Style 2: Radio Resource Allocation Control, Control Action ID 6: Slice-level PRB quota in DU. Note that the RIC Control Message generated by xapp_oran_slice_ctrl has the wrong format. To get a correct message, you can use ORAN-SC-RIC and simple_rc_xapp.py.

2. No, currently only PRB limits are supported per UE. Note that only E2SM-KPM and E2SM-RC are supported. MAC_SM is a custom FlexRIC module, and it will not be supported.

3. Please analyse how Slice-level PRB quota control is implemented. The MCS limits are already implemented, but can be set only in config file. The main task would be to expose them to E2 agent.