Three types of RRC message are used to transfer system information: the MIB message,
the SIB1 message and SI messages.An SI message includes one or more SIBs (SIB2- SIB13) . MIB is transmitted on PBCH while SIBs are trasmitted on PDSCH.
Overall SIB Scheduling concept is as follows.
i) MIB is transmitted at a fixed cycles (every 4 frames starting from SFN 0) .
ii) SIB1 is also transmitted at the fixed cycles (every 8 frames starting from SFN 0).
iii) All other SIB are being transmitted at the cycles specified by SIB scheduling information elements in SIB1
An SI message includes one or more SIBs (SIB2- SIB13) which have the same scheduling requirements(periodicity).The mapping of SIBs to SI messages is flexibly configurable by schedulingInfoList included in SystemInformationBlockType1.