Radio Link Failure:When UE is in Connected mode we have a Radio Link between UE and e-NodeB and the Radio Link is Existing between UE and eNodeB only.
Radio Link Failure Causes: 1.)PDCCH Block Error Rate (BLER) is> 10% is Observed at PHY.
2.)RRC Connectio Reconfiguration Failure(To Setup/Release Measurements,To Setup/Modify/Release Bearers).
3.)RRC Connection Reconfiguration Failure(Handover Failure).
4.) Max RACH Preamble Transmission reached.
5.)Max RLC Retransmission reached(RLC Unrecoverable error).
6.)PDCP Integrity check Failure.
7.)Uplink Time alignment Timer Expiry.