Differences in location management

Service continuity policy during handover

RNC cache forwarding policy

eNodeB cache forwarding policy

Data synchronization policy during handovers

It is ensured by the serial number.

It is ensured by the serial number.

Prerequisite for triggering location update

In the IDLE or the CONNECTED state

Only in the IDLE state

Location update mechanism

The MS informs the SGSN of information about the MS, such
as the RA. When the RAU procedure is triggered between SGSNs, information,
such as control context and security context, is migrated. Resources
on the old SGSN are released.

The UE sends a message to inform the MME about the TA in
which the UE is located.

Informing the subscriber data management center of location
update

Inform the HLR of the location update procedure between
the SGSNs.

Inform the HSS of the TAU procedure between the MMEs.