lots that are available for uplink and downlink information transfer. For NRT packet data services, shared channels (USCH and DSCH) can be used to allow efficient allocations for a short period of time. Table 4.36 Mapping of Transport Channels to Physical Channels Transport Map to Physical channels channels Dedicated Physical Channel (DPCH) Primary Common Control Physical Channel (P-CCPCH) Secondary Common Control Physical Channel (S-CCPCH) Physical Random Access Channel (PRACH) Physical Uplink Shared Channel (PUSCH) Physical Downlink Shared Channel (PDSCH) Page Indicator Channel (PICH) Synchronization Channel (SCH) 4.4.12 Mapping Common Transport Channels The Broadcast Channel (BCH) We map the BCH onto the P-CCPCH, where the secondary SCH indicates in which time slot a mobile can find the P-CCPCH containing a BCH. For additional resources the BCH in P-CCPCH will comprise a pointer to additional FACH S-CCPCH resources in which this additional broadcast information will occur. 4.4.12.2 The Paging Channel (PCH) We map the PCH onto one or several S-CCPCHs while matching capacity to require- ments, indicate its location on the BCH, and always transmit it at a reference power level. To allow an efficient DRX, the PCH is divided into several paging sub-channels within the allocated multi-frame structure. See examples of multi-frame structures in [6]. Each paging sub-channel comes mapped onto two consecutive frames allocated to the PCH on the same S-CCPCH. Layer 3 information to a particular paging group ar- rives through the associated paging sub-channel. UE assignment to paging groups OC- curs independently of the assignment of UEs to paging indicators. 4.4.12.3 The Forward Channel (FACH) We map the FACH onto one or several S-CCPCHs. Indication of FACH location comes on the BCC, where both capacity and location can be changed when necessary. The FACH may or may not have power control. The UMTS Network and Radio Access Technology 4.4.12.4 The Random Access Channel (RACH) The RACH, which we map onto the PRACH, has intra