Difference between handover and Redirection in LTE ?

Question

Please explain what is the difference between handover and Redirection in LTE ?

Answer 1

One basic difference is "In handover procedure, target cell would be prepared and UE will latch on target cell based on the configuration sent by source enodeb to UE. Whereas in re-direction, target cell would n't be prepared for the Ue , And UE leave current cell and will try to latch on the cell/frequency, communicated by source eNB to UE.

So during handover procedure, UE will continue with the services which were being used by UE. But in case of re-direction, services will be interrupted.

Answer 2

When the UE is in RRC Connected mode on the serving cell while its measurements indicate that the neighbor cell ( Neighbor cell can be of the same RAT type or a different RAT type) is much better than the serving cell. Upon reporting this measurements to Source ENB , the ENB can ask the UE to handover to the target cell if
There exists the implementation of the interface between them .( For ex if the target and the source ENB have the X2 interface implemented then the Source ENB can handover the UE to the target ENB)

If there doesnot exists the implementation of the interface between them, then the obvious choice is to redirect the UE. Meaning the Source ENB shall release the connection of the UE and will ask the UE to redirect itself onto the target ENB by indicating the carrier frequency or the cell id in the RRC connection release message.