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• Health of RIC platform modules –
  • Ability to initiate a Health-check on each of the common platform modules within the RIC (e.g., logging, tracing, conflict manager, xAPP manager, subscription management, O1 Termination, A1 Mediator, etc.), store results and declare alarm/alert conditions [5 in Figure 1]
  • Ability for each common platform module in the RIC to perform a self-check [6]
    • Implementation Option[1]: The self-check can potentially leverage Kubernetes Liveness and Readiness probes. Liveness probes can be configured to execute a command, issue a http-get, and open a TCP socket against the container/pod.   Readiness probes can be configured to ensure the pod is ready before allowing it handle traffic.  To further check a module’s (pod) ability to communicate with other modules over RMR (RIC Message Router), each module could subscribe to its own topic, send a hello-world message regularly to itself and ensure it can send and receive messages.
  • Any alarm/alert conditions or clearing of alarms/alerts are sent immediately via the O1 VES interface. [7-8]
• Health of xAPPs
  • Ability of RIC to invoke Health-check requests to each of the xAPP instances deployed on the RIC [9]
  • Ability of each xAPP to perform Health-checks on itself and respond back to the RIC [10]
    • Implementation Option: See Implementation Option above for platform modules.
  • Any alarm/alert conditions or clearing of alarms/alerts are sent immediately via the O1 VES interface. [7-8]

External Interfaces

For northbound (NB) external interfaces, the RIC is responsible to check its interface functions - O1 Termination module and , A1 Mediator.  In , and E2 Termination modules.  

In addition, heartbeats or keep-alive signals over O1 are verified by the NB clients invoking the O1.  

The RIC also checks the E2 interface - initially its heartbeat to individual RAN resources, and progressive the latency of messages/data flow over E2.  heartbeat message come from RAN resources over the E2 interface.

Note: Since the role of RIC is to enable near realtime control loop actions, latency is an important set of telemetry to be collected and reported - E2 latency and RIC processing latency.  As RIC matures release over release, latency telemetry should be defined and implemented.

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