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HUAWEI AND ZTE RRC

REESTABLISHMENT

Background, Activation and

parameter recommendations

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The physical layer of the UE is able to generate an in-sync or out-of-sync

primitive once every 10 ms radio frame. It is also possible that conditions are such that neither primitive is generated

during a radio frame.

The in-sync or out-of-sync primitives are reported to the RRC layer which is

then responsible for acting appropriately. If N313 (default 20) consecutive out-

of-sync primitives are received then the UE starts timer T313 (default 3 s). IfN315 (default 1) successive in-sync indicators are received while T313 is

running then the UE stops T313 and the UE remains synchronized

If T313 expires before N315 in-sync indicators have been received the UE

recognizes that radio link failure has occurred. At this stage the UE releases

its dedicated physical channel configuration and attempts to complete a cellupdate using the random access channel.

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Either or both of timers T314 (default 12 s) and T315 (default 180 s) arestarted. The early versions of 3GPP TS 25.331 stated that T314 should beassociated with transparent and unacknowledged mode radio bearers

whereas T315 should be associated with acknowledged mode radio bearers.

This definition was subsequently removed, allowing the RNC to select whichRadio Access Bearers (RAB) to associate with each timer. The relevant timer isnow signaled as part of the RAB establishment procedure.

Figure_1 Radio link failure avoided

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Figure_2 Radio link failure with recovery (completed)

Figure_2 Radio link failure with recovery (failed)

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T302:(Proposed to change from 2 sec to 1.4 Sec)RRC Connected mode timer, sent in

SIB 1 and UTRAN Mobility Information

Start :When MAC layer indicates success or failure of sending either a Cell

Update or a URA Update.

Stop: When a Cell Update Confirm or URA Update Confirm is received.Upon Expiry: Re-transmit the Cell Update or URA update if V302

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HUAWEI RRC REESTABLISHMENT ACTIVATION

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SIGNALING PROCEDURE AFTER SWTICH UPDATE

Scenario 1 Scenario 2 Scenario 3

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RECOMMENDED UE TIMER PARAMETER SET

FOR BOTH ZTE AND HUAWEI