A Universal Mobile Telecommunication System (UMTS) is a broadband, packet based system for the transmission of text, digitized voice, video and multi-media. It is a highly subscribed to standard for third generation and is generally based on Wideband Coded Division Multiple Access (W-CDMA).
In a UMTS network, a Radio Resource Control (RRC) part of the protocol stack is responsible for the assignment, configuration and release of radio resources between the UE and the UTRAN. This RRC protocol is described in detail in the 3GPP TS 25.331 specifications. Two basic modes that the UE can be in are defined as “idle mode” and “UTRA connected mode”. UTRA stands for UMTS Terrestrial Radio Access. In idle mode, the UE is required to request a RRC connection whenever it wants to send any user data or in response to a page whenever the UTRAN or the Serving GPRS Support Node (SGSN) pages it to receive data from an external data network such as a push server. Idle and Connected mode behaviors are described in detail in 3GPP specifications TS 25.304 and TS 25.331 respectively. To be able to exchange data, a UE in idle mode first needs to set up a RRC Connection process, which moves it to one of the states of the connected mode. The UE is also assigned a radio bearer by the network as part of the process. Initial radio bearer resource configuration and any subsequent change in bearer configuration are controlled by the network.
When in a UTRA RRC connected mode, the device can be in one of four states. These are:                CELL-DCH: A dedicated channel is allocated to the UE in uplink and downlink in this state to exchange data. The UE must perform actions as outlined in 3GPP 25.331.        CELL_FACH: no dedicated channel is allocated to the user equipment in this state. Instead, common channels are used to exchange a small amount of bursty data. The UE must perform actions as outlined in 3GPP 25.331 which includes the cell selection process as defined in 3GPP TS 25.304.        CELL_PCH: the UE uses Discontinuous Reception (DRX) to monitor broadcast messages and pages via a Paging Indicator Channel (PICH). No uplink activity is possible. The UE must perform actions as outlined in 3GPP 25.331 which includes the cell selection process as defined in 3GPP TS 25.304. The UE must perform the CELL UPDATE procedure after cell reselection.        URA_PCH: the UE uses Discontinuous Reception (DRX) to monitor broadcast messages and pages via a Paging Indicator Channel (PICH). No uplink activity is possible. The UE must perform actions as outlined in 3GPP 25.331 including the cell selection process as defined in 3GPP TS 25.304. This state is similar to CELL_PCH, except that URA UPDATE procedure is only triggered via URA reselection.        
The transition from an idle mode to the different states of connected mode and vise-versa is controlled by the UTRAN. The transition may not be optimal for all underlying services on the UE.
The problem with the above is that the RRC radio bearer allocation and adaptation as well as RRC state transition profile is static for every device connected to the network regardless of subscription profile. It could even be static for all the applications on the device. The subscription may be closely tied to the applications of a handset, such as that for always-on applications. If radio bearer allocation and adaptation is not based on the underlying application or subscription for which the UE initiates the RRC request, it could lead to suboptimal performance such as increase in latency, a reduction in effective data rate, etc. In addition, since the UTRAN controls when the RRC connected state is changed to a different, less battery intensive state or into an idle mode, a UE may be forced to stay in a higher data rate and intensive battery state than the required state or mode, thereby draining battery life and wasting network resources.