on of the PHY RAC for radio resources. Allocate radio/transport resources RRC: EPS radio bearer setup Configure MAC/scheduler PHY radio BS establishment UE internal configuration and binding of application-UL filter- EPS radio BS-Phys radio BS RRC: EPS radio BS response EPS bearer setup response Create redicated bearer response EPS bearer service established EPS radio BS EPS access BS EPS: Evolved Packet System NAS: Non-access Stratum BS: Bearer Service GBR: Guaranteed Bit Rate MBR: Maximum Bit Rate AMBR: Aggregate Maximum Bit Rate Figure 4.3 Radio admission control (RAC) in conjunction with evolved packet system (EPS) bearer service establishment. From the LTE radio access network's perspective, the mobility management entity of the core network requests an EPS bearer (characterized by a set of QoS parameters). The RAN exercises admission control for guaranteed bit rate (GBR) services and, in case of admission, estab- lishes the underlying physical radio bearer service that will support the requested EPS bearer. radio resource situation due to mobility or for other reasons. RBC is involved in the release of radio resources associated with radio bearers at session termination, handover, or other occasions. It is important to realize that RBC and "setting up" a radio bearer in LTE do not imply the static assignment and dedication of radio resources to users or user data flows. For example, when the RAC is executed upon a radio bearer setup, the RAN assesses the necessary radio resources (typically on a statistical basis) and makes an admission decision. Thus, RAC has the responsibil- ity to keep the overall load within the feasible region in which the RAN remains stable and is able to deliver the expected QoS. Subsequently, it is the task of the scheduler to assign resources dynamically to users SO that the QoS commitments are indeed kept and radio resources remain highly utilized. Radio admission control has the task to check the availability of radio resources when setting up a GBR radio bearer (upon an EPS bear