This Page Covers LTE Timers Which Include T300

8/10/2019 This Page Covers LTE Timers Which Include T300

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This page covers LTE timers which include T300, T301, T303, T304, T305, T310, T311, T320 andT321.

LTETimers

Function at Start/Stop/Expiry

T300

>>tarts at the !!" connection !E# transmit>>tops at the !eceipt o$ !!" connection setup or re%ect message &! at the cellreselection time &! upon a'ortion o$ connection esta'lishment '( )igher la(ers *L2+L3.>>-t the epir( per$orms the actions

T301

>>tarts at the !!" "onnection !e/esta'lishment !E#ET>>tops at the !eceipt o$ !!" "onnection !e/esta'lishment &!!!" "onnection !e/Esta'lishment !EE"T message &!hen selected cell 'ecomes unsuita'le to continue $urther>>-t epir(, it o to !!"6LE mode

T303

>>tarts when access is 'arred while per$orming !!" "&77E"T&7 ET-8L)9E7T$or 9&*9o'ile &riginating calls>>tops while entering !!""&77E"TE6 and upon cell re/selection mode

>>-t epir(, n$orms higher la(ers a'out 'arring alleviation

T304

>>tarts at the !eceipt o$ !!" "&77E"T&7 !E"&7:!-T&7 message along with9o'ilit( "ontrol n$o &! at the receipt o$ mo'ilit( $rom ET!- command message including"ELL ")-7E &!6E!>>tops at the success$ul completion o$ )-76&;E! to ET!- or "ELL ")-7E&!6E! is met>>-t epir(, it per$orms action 'ased on need.1. n the case o$ "ELL ")-7E &!6E! $rom E/T!- &! intra E/T!- handover, initiatethe !!" connection re/esta'lishment procedure.2. n case o$ )-76&;E! to E/T!-, per$orm the actions de$ined as per the speci$icationsapplica'le $or the source !-T.

T305

>>starts when access is 'arred while per$orming !!" "&77E"T&7 ET-8L)9E7T$or 9& signaling

>>tops when entering !!""&77E"TE6 and when E does cell re/selection>> -t epir(, n$orms higher la(ers a'out 'arring alleviation

T310

>>tarts when E detects >-t epir( it enters !!" 6LE state

T320

>> tarts upon receipt o$ t320 or upon cell re/ selection to E/T!- $rom another !-T withvalidit( time con$igured $or dedicated priorities *in which case the remaining validit( time isapplied.>>tops upon entering !!""&77E"TE6 state, when >starts upon receipt o$ measConfig including a reportConfig with the purpose setto reportCG>> tops at either o$ $ollowing cases?


2/9

1. pon acuiring the in$ormation needed to set all $ields o$ g!o"a!Ce!!#$or the reuestedcell2. upon receipt o$ measConfigthat includes removal o$ thereportConfigwith the purposeset to reportCG>> -t epir( initiates the measurement reporting procedure, stop per$orming the relatedmeasurements and remove the correspondingmeas$

Timer Start Stop

T300 Transmission of RRCConnectionRequest Reception of RRCConnectionSetup or

RRCConnectionReject message, cellre-selection and upon abortion of

connection establisment by upperlayers

T30% Transmission ofRRCConnectionReestabilsmentRequest

Reception ofRRCConnectionReestablisment or

RRCConnectionReestablismentRejecmessage as &ell as &en te selecte

cell becomes unsuitable

T30 Reception of RRCConnectionReject &ile performingRRC connection establisment .pon entering RRC(C/CT* andupon cell re-selection

T303 Access barred &ile performing RRC connection

establisment for mobile originating calls

.pon entering RRC(C/CT* and

upon cell re-selection

T30 Reception of RRCConnectionReconfiguration messageincluding te 4obilityControl )nfo or reception of4obility5rom.TRACommand message including

CellCange/rder

Criterion for successful completion ofando1er to .TRA or cell cangeorder is met 6te criterion is specified

in te target RAT in case of inter-RAT
http://www.sharetechnote.com/html/Handbook_LTE_T300.htmlhttp://www.sharetechnote.com/html/Handbook_LTE_T304.htmlhttp://www.sharetechnote.com/html/Handbook_LTE_T304.htmlhttp://www.sharetechnote.com/html/Handbook_LTE_T300.html


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T30" Access barred &ile performing RRCconnection

establisment for mobile originating signalling

.pon entering RRC(C/CT* and

upon cell re-selection

T3%0 .pon detecting pysical layer problems i#e# upon

recei1ing 3%0 consecuti1e out-of-sync indicationsfrom lo&er layers

.pon recei1ing 3%% consecuti1e in-

sync indications from lo&er layers,upon triggering te ando1er

procedure and upon initiating teconnection re-establisment

procedure

T3%% .pon initiating te RRCconnectionreestablismentmprocedure

Selection of a suitable -.TRA cell ora cell using anoter RAT#

T30 .pon recei1ing t30 or upon cell 6re7selection to -.TRA from anoter RAT &it 1alidity time configured

for dedicated priorities 6in &ic case te remaining1alidity time is applied7#

.pon entering RRC(C/CT*,&en !+4 selection is performed on

request by AS, or upon cell6re7selection to anoter RAT 6in &ic

case te timer is carried on to teoter RAT7#

T3% .pon recei1ing measConfig including a reportConfig

&it te purpose set to reportC')

.pon acquiring te information

needed to set all fields of cell'lobal)dfor te requested cell, upon recei1ing

measConfig tat includes remo1al ofte reportConfig &it te purpose se

to reportC')
http://www.sharetechnote.com/html/Handbook_LTE_T310.htmlhttp://www.sharetechnote.com/html/Handbook_LTE_T310.html


4/9

$rop Sessions %&art 1 of 2'

Lauro

2( )ar 2012 *+01 &) 0

There are several reasons wh( a session ma( drop in LTE. )owever, whether thesession is dropped or not depends on the particular vendor implementation. That is, thedrop ma( 'e caused '( a E message or '( measurements carried out '( the e7ode8.

8oth the E and the e7ode8 ma( chec@ i$ the radio lin@ is in/s(nch. n this 'log, we willdescri'e t,e acti-ities t,at t,e .E carries out to determine i$ the radio lin@ is in/s(nchand their conseuences.


5/9

$ the E detects n310 consecutive out/o$/s(nc indications, it starts the t310 timer. $ thetimer epires, the lin@ has $ailed. $ the E detects n311 consecutive in/s(nc indicationsprior to the t310 timer epiring, then the timer is stopped and the lin@ has not $ailed.

So 7,at ,appens after t,e .E #etects t,at t,e !in fai!e#

$ the E determines that the !adio Lin@ $ails, the E will tr( to reconnect with an !!""onnection !eesta'lishment !euest message. There are a num'er o$ cases thatcould occur 'ased on vendor implementation.

,at if t,e e8o#e9 #oes not support C Connection eesta"!is,ment

The case shown in the $igure 'elow is the simplest case where the e78 does notsupport !!" "onnection reesta'lishment. n this case, the e78 responds with an !!""onnection !eesta'lishment !e%ect message. imultaneousl(, the e78 will realiAe thatthe radio lin@ has $ailed and reuest the connection to 'e release to the 99E. t $irst

reuests to drop the E "ontet or the connection to the E. The cause value is set toB!adio "onnection with E Lost.C The 99E will respond with a E "ontet !elease"ommand. -t this point, the e7ode8 will respond with the E "ontet !elease"omplete message to the 99E and will release the !!" connection with the E '(sending an !!" "onnection !elease to the E. 6epending on the !: conditions, theE ma( or ma( not receive this message.
http://lteuniversity.com/cfs-file.ashx/__key/communityserver-blogs-components-weblogfiles/00-00-00-00-92/6862.Fig1.png


6/9

,at if t,e e8o#e9 #oessupport C Connection eesta"!is,ment

$ the e7ode8 supports !!" connection !eesta'lishment, and assumingthat thee7ode8 $inds 'oth the L and 6L in s(nch when it receives the !!" connection

reesta'lishment reuest message, two scenarios ma( occur? !!" connectionreesta'lishment success and $ailure.

n the case o$ an !!" connection reesta'lishment success, the $ollowing signaling iscarried echanged.


7/9

$ the !!" connection gets success$ull( reesta'lished, then the session does not getdropped.

$ the !!" connection reesta'lishment procedure $ails in one o$ its steps, then thee7ode8 will send the E contet release reuest message to the 99E. 7ote that the!!" connection reesta'lishment process ma( $ail in several steps. 8elow, in the $igure,onl( one case is shown.


8/9

$ the !!" connection reesta'lishment $ails, then the session is dropped.

:es; you are rig,t


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Documents

This Page Covers LTE Timers Which Include T300