LTE的UE specific paging cycle是哪条消息下达的？为什么会是UE-specific？

应该是在SIB2消息里带下来的：
T: DRX cycle of the UE. T is determined by the shortest of the UE specific DRX value, if allocated by upper layers, and a default DRX value broadcast in system information. If UE specific DRX is not configured by upper layers, the default value is applied.