Section: 8.9.11 IAB-node OAM
Content: NOTE: The general principles and procedures described in this clause does not apply to ng-eNB. The IAB-node receives commands, configuration data and software downloads (e.g. for equipment software upgrades) from its OAM system. The IAB-node can also send alarms and traffic counter information to its OAM system. The transport connection between the IAB-node and its OAM, using IP, is provided by the IAB-MT’s PDU session via 5G network, or the IAB-MT’s PDN connection via LTE network when IAB-MT uses EN-DC. NOTE: The transport connection between the IAB-node and its OAM may also be provided using the Backhaul IP layer by implementation. Alarms in the IAB generate bursts of high-priority traffic, to be transported in real time. Traffic counters generate bursts of traffic, but their transport need not be real-time. Configuration messages from OAM to the IAB will also generate small bursts of traffic, possibly with lower priority than alarms but still delay-sensitive: when a configuration is committed on the OAM, the time interval between the commitment and the effect on the equipment shall be small. Alarm messages and commands should be transported on a high-priority bearer, while counters may be transported on a lower priority bearer. OAM software download to the IAB may generate larger amounts of data, but both the required data rate and the priority of this kind of traffic are much lower than in the case of alarms, commands and counters. For different types of OAM traffic, it is necessary to use different DRBs between the IAB-MT and the serving DU, and different BH RLC channels for intermediate hops, with different QoS parameters. Aggregation of F1-U traffic for OAM with other F1-U traffic on the same BH RLC channels is not precluded. The QoS parameters are provided to the IAB-donor during the IAB-MT’s PDU session establishment, or the IAB-MT’s PDN connection establishment when IAB-MT uses EN-DC. NOTE: When the transport connection between the IAB-node and its OAM is provided by the Backhaul IP layer, the OAM traffic may be aggregated with other traffic types on the same BH RLC channel. The QoS for OAM is ensured by implementation. The continuity of OAM connectivity needs to be ensured as the mobile IAB-node moves across the mobile network.