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ManagementBy SW PA Frank Lin@ext.2612

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EPS Mobility Management

-In the EMM-DEREGISTERED state, the EMM context in MME holds novalid location or routing information for the UE. The UE is not reachable by

, .In the EMM-DEREGISTERED state, some UE context can still be stored in

the UE and MME, e.g. to avoid running an AKA(Authentication and Key.

EMM-REGISTERED:The UE enters the EMM-REGISTERED state by a successful registrationrocedure which is either an Attach rocedure or a Trackin Area U date

procedure. In the EMM-REGISTERED state, the UE can receive servicesthat require registration in the EPS.The UE location is known in the MME to at least an accurac of thetracking area list allocated to that UE (excludingsome abnormal cases).

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EPS Mobility Management

- ,perform a tracking area update if the new TA is not in the list of TAs thatthe UE has received from the network in order to maintain the registration

.perform the periodic tracking area updating procedure to notify the EPC

that the UE is available.procedure.perform the service request procedure in order to establish the radiobearers when u link user data is to be sent.

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EPS Connection Management

-A UE is in ECM-IDLE state when no NAS signaling connection betweenUE and network exists. In ECM-IDLE state, a UE performs cell

.according to TS 23.122 [10].

There exists no UE context in E-UTRAN for the UE in the ECM-IDLE state.-_ _

state.The UE and the MME shall enter the ECM-CONNECTED state when thesi nalin connection is established between the UE and the MME.

ECM-CONNECTED:The UE location is known in the MME with an accuracy of a cell ID. Themobilit of UE is handled b the handoverprocedure. The UE performs the tracking area update procedure when TAIin the EMM system information is not in the list of TA's that the UE is

registered with the network.For a UE in the ECM-CONNECTED state, there exists a signalingconnection between the UE and the MME. Thesignaling connection is made up of two parts: an RRC connection and anS1_MME connection.

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EPS Connection Management

-The S1 release procedure changes the state at both UE and MME fromECM-CONNECTED to ECM-IDLE.

, . .due to radio link error or out of coverage.

In this case, there can be temporal mismatch between the ECM-state in-

MME.

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UE State Management

connection management (ECM) and EPS mobility management (EMM): ECM-CONNECTED

connection on the S1-MME interface.

ECM-IDLE

on the S1-MME interface. EMM-REGISTEREDThe re istration rocedure has been successful for the UE.

EMM-DEGISTEREDThe UE has been switched off.

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UE State Management

- -RRC_IDLE and EUTRARRC_CONNECTED.

initiation and support

of EPC connection management state transitions such as:Triggering the UE to initiate a ECM-IDLE to ECM-CONNECTED transition Initial accessTransition to ECM-CONNECTED

Signaling connection releaseTransition to ECM-IDLE Error scenariosFor example RRC connection re-establishment

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Reading Experience

. ,are based on UE but on MME in LTE.In LTE:

ECM-CONNECTEDEither the RRC isconnected on the air EMM-REGISTERED

MME

interface or the S1 isconnected the S1-MMEinterface.

The registrationprocedure has beensuccessful for the UE.

oo

ECM-IDLEThe RRC is released on

EMM-DEGISTEREDThe UE has been

t e a r nter ace an t eS1 is not connected on

the S1-MME interface.

.