Page 1030 - 5G Basics - Core Network Aspects

2 Transport aspects

Act_min_Mds = max(min_Mds, DTA_min_Mds)
Act_max_Mds = min(max_Mds, DTA_max_Mds)
The DRA shall select an Mds value such that Act_min_Mds ≤ Mds ≤ Act_max_Mds. In case Act_min_Mds >
Act_max_Mds, the value of hs_Mds shall be used by the DRA for the TDD frame configuration. In this case,
the ETR is lower than DTA_ETR_min but is still greater than or equal to ETR_min.
Upon completion of an OLR occurring on the line, the values of min_Mds, max_Mds, Act_min_Mds and
Act_max_Mds shall be updated by the DRA. If the ETR falls below DTA_ETR_min after an OLR procedure, the
DRA shall recalculate the values of min_Mds, max_Mds, Act_min_Mds and Act_max_Mds. If, as a result of this
recalculation, a change of Mds is needed to increase the rate above DTA_ETR_min, the DRA shall request a
change from the FTU-O, in compliance with the configured value of DTA_SMax. If the needed change
cannot be accomplished with one request, the DRA shall make the necessary number of requests. The valid
values and coding for DTA_ETR_min shall be the same as for ETR_min as specified in clause 11.4.2.1.

The control parameter DTA_ETR_min is derived by the DRA from the DPU-MIB configuration parameter for
the minimum expected throughput for DTA (DTA_MINETR).

NOTE 1 – To comply with the requirement ETR ≥ DTA_ETR_min in the upstream, under unfavourable loop conditions,
the Act_max_Mds might be lower than DTA_max_Mds. In this case the DRA will report in the DPU-MIB a GDRds (see
clause 7.11.1.3 of [ITU-T G.997.2]) that is lower than the NDRds, even in case the DRA or L2+ functions do not have
any intrinsic throughput capability limitations.
NOTE 2 – To comply with the requirement ETR ≥ DTA_ETR_min in the downstream, under unfavourable loop
conditions, the Act_min_Mds might be higher than DTA_min_Mds. In this case the DRA will report in the DPU-MIB a
GDRus (see clause 7.11.1.3 of [ITU-T G.997.2]) that is lower than the NDRus, even in case the DRA or L2+ functions do
not have any intrinsic throughput capability limitations.
T.2.8 Maximum net data rate for DTA (DTA_NDR_max)

See clause X.6.7.5.

T.3 Coordination between the link state request and the DTA request
The DRA shall only send a DTA.request primitive (see clause X.6.1) if the current link state is L0. Moreover,
the DRA shall not send the DTA.request primitive after a LinkState.Request is sent by the DRA to the FTU-O
until the corresponding LinkState.Confirm is received by the DRA.

1020