sufficient radio channel quality. Note 2: The rate of non congestion related packet losses that may occur between a radio base station and a PCEF should be regarded to be negligible. A PELR (packet error loss rate) value specified for a standardized QCI therefore applies completely to the radio interface between a UE and radio base station. Note 3: This QCI is typically associated with an operator controlled service, that is, a service where the SDF aggregate's uplink/downlink packet filters are known at the point in time wh en the SDF aggregate is authorized. In case of E-UTRAN this is the point in time when a corresponding dedicated EPS bearer is established / modified. Note 4: This QCI could be used for prioritization of specific services according to operator configuration. Note 5: This QCI could be used for a dedicated "premium bearer" (e.g., associated with premium content) for any subscriber/subscriber group. Also in this case, the SDF aggregate's uplink / downlink packet filters are known at the point in time when the SDF aggregate is authorized. Alternatively, this QCI could be used for the default bearer of a UE/PDN for "premium subscribers". Note 6: This QCI is typically used for the default bearer of a UE/PDN for non privileged subscribers. Note that AMBR can be used as a "tool" to provide subscriber differentiation between subscriber groups connected to the same PDN with the same QCI on the default bearer. Source: C 2009 3GPP [23] Next Generation Mobile Communications Ecosystem RRM functions User plane Control plane Admission Semi-persistent Layer 3 management control scheduling Hybrid ARQ Dynamic Layer 2 manager scheduling Link adaptation PDCCH Layer 1 adaptation manager Figure 3.29 RRM functionalities at different layers. Reproduced with permission from Laselva et al. C IEEE [22] 3.9.2.1.2 Semi-Persistent Scheduling It allows periodic allocation of certain transmission resources for a particular user which is initially configured by RRC. The periodic allocation represents regular scheduling of a fi