imes that a paging message has to be re-sent before it is answered, also has a profound effect. It can be seen that with one block reserved for AGCH and assuming three paging numbers per paging block, 25 pages can be sent per second. The paging traffic observed in a typical network can be found by means of: the number of pages per second per user; the number of subscribers; the paging success ratio. The signalling load is highly dependent on the parameters. In the same LA/RA, the paging load should be monitored. Note that if there is only one small cell in a given LA/RA, where a combined channel structure is in use, this will be the bottleneck if paging blocking criteria are strictly followed. In other words, the smallest cell in the LA/RA will set the PCH limit. 2.8.3 Parameter Planning in the WCDMA Network Physical layer procedures Logical Channels Logical channels were created to transmit a specific content. There are, for instance, logical channels to transmit the cell system information paging information or user data. Logical channels are offered as a data transfer service by the Medium Access Control (MAC) layer to the next higher layer. Consequently, logical channels are in use between the mobile phone and the RNC. Logical channels are characterised by Radio Network Planning and Optimisation the specific content to be transmitted: user data (DTCH), control messages (DCCH, CCCH), broadcast data (CTCH) and cell system information (BCCH). Control Channels (CCH) Broadcast Control Channel (BCCH) System information is made available on this channel. The system information informs the UE about the serving PLMN, the serving cell, neighbourhood lists, measurement parameters, etc. This information is permanently broadcast in the downlink. Paging Control Channel (PCCH) Given the BCCH information, the UE can determine at what times it may be paged. Paging is required when the RNC has no dedicated connection to the UE. The PCCH is a downlink channel. Common Control Channel (CCCH) Control information is transmitted on 