Connection Management Feature Parameter Description(ERAN2.0_01)

eRAN

Connection Management Feature Parameter Description

Issue 01

Date 2010-07-30

Huawei Proprietary and Confidential Copyright Huawei Technologies Co., Ltd.

Copyright Huawei Technologies Co., Ltd. 2010. All rights reserved. No part of this document may be reproduced or transmitted in any form or by any means without prior written consent of Huawei Technologies Co., Ltd. Trademarks and Permissions

and other Huawei trademarks are the property of Huawei Technologies Co., Ltd. All other trademarks and trade names mentioned in this document are the property of their respective holders. Notice The purchased products, services and features are stipulated by the contract made between Huawei and the customer. All or part of the products, services and features described in this document may not be within the purchase scope or the usage scope. Unless otherwise specified in the contract, all statements, information, and recommendations in this document are provided "AS IS" without warranties, guarantees or representations of any kind, either express or implied. The information in this document is subject to change without notice. Every effort has been made in the preparation of this document to ensure accuracy of the contents, but all statements, information, and recommendations in this document do not constitute the warranty of any kind, express or implied.

Huawei Technologies Co., Ltd.

Address: Huawei Industrial Base Bantian, Longgang Shenzhen 518129 People's Republic of China

Website: http://www.huawei.com

Email: [email protected]

Huawei Proprietary and Confidential Copyright Huawei Technologies Co., Ltd.

eRAN Connection Management Contents

Issue 01 (2010-07-30) Huawei Proprietary and Confidential Copyright Huawei Technologies Co., Ltd.

iii

Contents

1 Introduction.................................................................................................................................1-1 1.1 Scope.............................................................................................................................................................1-1 1.2 Intended Audience.........................................................................................................................................1-1 1.3 Change History..............................................................................................................................................1-1

2 Overview of Connection Management..................................................................................2-3 2.1 Random Access .............................................................................................................................................2-4 2.2 UE Connection ..............................................................................................................................................2-4

2.2.1 Signaling Connection...........................................................................................................................2-5 2.2.2 RB Management ..................................................................................................................................2-6

3 Related Concepts........................................................................................................................3-7 3.1 Tracking Area ................................................................................................................................................3-7 3.2 Access Stratum States....................................................................................................................................3-7 3.3 Non-Access Stratum States ...........................................................................................................................3-8 3.4 Call Types in the NAS...................................................................................................................................3-8

4 Random Access.........................................................................................................................4-10 4.1 Random Access Preambles..........................................................................................................................4-11

4.1.1 Overview............................................................................................................................................4-11 4.1.2 Preamble Sequence Generation and Classification ............................................................................4-11

4.2 Random Access Procedure ..........................................................................................................................4-12 4.2.1 Contention-Based RA Procedure .......................................................................................................4-13 4.2.2 Non-Contention-Based RA Procedure ...............................................................................................4-15

4.3 RA Backoff Control ....................................................................................................................................4-15

5 Signaling Connection Processing .........................................................................................5-17 5.1 RRC Connection Establishment..................................................................................................................5-17 5.2 Dedicated S1 Connection Establishment.....................................................................................................5-19 5.3 RRC Connection Reestablishment ..............................................................................................................5-20 5.4 Signaling Link Release................................................................................................................................5-22

6 RB Management .......................................................................................................................6-24 6.1 SRB2 Establishment and Modification .......................................................................................................6-24 6.2 DRB Establishment and Modification ........................................................................................................6-25 6.3 DRB Release ...............................................................................................................................................6-26

Contents eRAN

Connection Management

iv Huawei Proprietary and Confidential Copyright Huawei Technologies Co., Ltd.

Issue 01 (2010-07-30)

7 Engineering Guidelines..........................................................................................................7-28 7.1 T302 ............................................................................................................................................................7-28 7.2 RA Configurations ......................................................................................................................................7-28

8 Parameters ...................................................................................................................................8-1

9 Counters .......................................................................................................................................9-1

10 Glossary ...................................................................................................................................10-2 10.1 Terms.........................................................................................................................................................10-2 10.2 Acronyms and Abbreviations ....................................................................................................................10-2

11 Reference Documents............................................................................................................11-4

eRAN Connection Management 1 Introduction


1-1

1 Introduction 1.1 Scope

es the management of the connections between the User Equipment (UE), E-UTRAN NodeB (eNodeB), and Mobility Management Entity (MME). Connection

he on is released when the

service is complete.

ibes Random Access (RA), signaling connection management, ement, and related engineering guidelines.

1.2 Intend This document is intended for:

z Personnel who need to understand connection management o work with Huawei products

1.3 Change History This nformation on the changes in different document versions. There are

o

z e Connection Management feature of a specific product version.

orial change: refers to the change in wording or the addition of the information that

Document Issues The document issue is as follows:

01 (2010-07-30)

This document describ

management is a series of processes in which dedicated connection between the UE and tMME is established for certain UE service and the dedicated connecti

This document also descrRadio Bearer (RB) manag

ed Audience

z Personnel wh

section provides itw types of changes, which are defined as follows:

Feature change: refers to the change in th

z Editwas not described in the earlier version.

zz Draft (2010-05-20)

1 Introduction eRAN


1-2 Huawei Proprietary and Confidential Copyright Huawei Technologies Co., Ltd.

Issue 01 (2010-07-30)

01 (2010-07-30) C f 05-20), issue 01 (2010-07-3 porates the changes described in the l

ompared with dra following tab

t (2010-e.

0) incor

Change Type Change Description Parameter Change

Feature change None. None.

The description about theparameters related to the

transmit

s deleted. ee the

on.

None.

power of the PRACH iFor detailed description, sPower Control Feature Parameter Descripti

The description about engineering guidelines is optimized, and a reference document is added.

mended value of the RachAlgoSwitch parameter is provided.

The recom

Editorial change

The mapping relationship between the feature and the

None.

feature list is added.

Draft (2010-05-2C e 01inc ang

0) ompared with issu

orporates the ch01 (2010-01-31) of eRAN1.1, draft (2es described in the following table.

0-05-20) of eRAN2.0

Change Type Change Description Parameter Change

Feature change The configurable parameters related to the connection management algorithms are changed.

e

cvTargetPwr tep

g parameter is

bleFmt z T302 z UeInactiveTimer

The following parameters ardeleted: z PreambInitRz PwrRampingSThe followinadded: z CellRadius z Pream

Editorial change None. None.

eRAN Connection Management 2 Overview of Connection Management


2-3

2 Overview of Connection Management Connection management in the LTE system involves management of the connections between the UE, eNodeB, and MME. The connection management is performed in both control plane and user plane.

Figure 2-1 shows the functions involved in connection management. RA is triggered by a when the UE needs to communicate with the network for purposes such as service request, location update, and paging. After the RA procedure is complete, the connection between UE and the MME in the control plane is started. Connection in the control plane consistsRadio Resource Control (RRC) signaling connection and dedicated S1 connection. RRC signaling connection refers to signaling connection between the UE and the eNodeB on the Uu interf

UE

the of

ace, and dedicated S1 connection refers to the signaling connection between the eNodeB and the MME. After the connection in the control plane is complete, the MME

odeB to establish E-UTRAN Radio Access Bearer (E-RAB) in the case of

E-R

NOTE

causes the eNservice request. Through RB management, the eNodeB establishes, modifies, and releases the

AB.

The security mode command procedure is not described in this document. For details about the related information, see the Security Feature Parameter Description.

2 Overview of Connection Management eRAN



Issue 01 (2010-07-30)

Figure 2-1 Connection establishment procedure

2.1 Random Access RA is the only policy for establishing and recovering the uplink synchronization between the UE and the eNodeB. Therefore, RA is important in the LTE system. RA consists of contention-based RA and non-contention-based RA. In contention-based RA procedure, the access may fail because a Random Access Channel (RACH) may fail to be allocated to the UE. In non-contention-based RA procedure, the eNodeB allocates a specified RACH to the UE. If the specified RACH is insufficient, the eNodeB requests the UE to initiate contention-based RA.

2.2 UE Connection UE connection consists of signaling connection in the control plane and RB management.

Signaling connection in this document refers to the signaling connection before security establishment. The connection involves RRC signaling connection and signaling connection on the S1 interface. RRC connection establishment is Signaling Radio Bearer-1 (SRB1) establishment. Signaling connection on the S1 interface is dedicated S1 connection.

RB management in this document refers to the E-RAB establishment procedure after security establishment. The procedure involves Signaling Radio Bearer-2 (SRB2) establishment and Data Radio Bearer (DRB) establishment.

In the LTE system, the services between a UE and a Packet Data Network (PDN)-Gateway (GW) with the same QoS class are referred to as an Evolved Packet System (EPS) bearer. In the EPS bearer, the section between the UE and the eNodeB is RB, and the section between

eRAN Connection Management 2 Overview of Connection Management


2-5

the eNodeB and the Serving Gateway (S-GW) is S1 bearer, as shown in Figure 2-2. RB and S1 bearer are collectively referred to as E-RAB.

RB is classified into Signaling Radio Bearer (SRB) and DRB according to different bearing contents.

A SRB bears signaling, which is in the control plane. According to different signaling, three different SRBs can be defined as follows:

z Signaling Radio Bearer-0 (SRB0): bearing the RRC signaling prior to RRC connection establishment. The SRB0 is transmitted over the Common Control Channel (CCCH) through the Transparent Mode (TM) in the Radio Link Control (RLC) layer.

z SRB1: bearing the NAS signaling prior to SRB2 establishment and RRC signaling, which may contain Non-Access Stratum (NAS) signaling messages. The SRB1 is transmitted over the Dedicated Control Channel (DCCH) through the Acknowledged Mode (AM) in the RLC layer.

z SRB2: bearing NAS signaling. The SRB2 is transmitted over the DCCH through the AM in the RLC layer. The priority of the SRB2 is lower than that of the SRB1, and the SRB2 can be established only after the security is activated.

A DRB bears data in the user plane. A maximum of eight DRBs can be established between the UE and the eNodeB according to different QoS classes.

Figure 2-2 Different bearer types

2.2.1 Signaling Connection Signaling connection consists of the RRC connection between the UE and the eNodeB and dedicated S1 connection between the eNodeB and the MME.

Signaling connection establishment is triggered by the UE, which first requests RRC connection. After the RRC connection is established, the eNodeB starts the dedicated S1 connection over the S1 interface. Thus, signaling connection between the eNodeB and the MME can be established. The completion of the dedicated S1 connection indicates that the connection between the UE and the MME is complete.

2 Overview of Connection Management eRAN



Issue 01 (2010-07-30)

Signaling connection release is triggered by the MME. The connection of the E-RAB bearing services is released first, and then the dedicated S1 connection is released. The MME may also release dedicated S1 connection to release all the S1 resources.

2.2.2 RB Management RB management consists of the management of the SRB2 and DRB after security is established, which involves the establishment and modification of the DRB and SRB2 and also release of the DRB. The SRB2 cannot be released through RB management. Instead, the SRB2 is released with the SRB1 during signaling connection release.

eRAN Connection Management 3 Related Concepts


3-7

3 Related Concepts 3.1 Trackin

plemented when the UE moves among the TAs in the TAL. When a UE

Each cell of an eNodeB belongs to only one TA, and only the corresponding TA information needs to be broadcast in the cell. When the MME sends a paging message, all the cells

L, the information of which is stored in the UE, can receive the

3.2 Access

ted

essages to the UE.

When a UE is in RRC_CONNECTED mode, the eNodeB obtains the UE context. In this case, the eNodeB can control the UE for data transmission and handover, inform the UE about related scheduling information, receive the feedback information about channel quality and related information sent from the UE, and send SI messages to the UE.

g Area Tracking Area (TA) is a concept introduced in the LTE system for location management of UEs. A TA is identified by a Tracking Area Identity (TAI), which consists of the Mobile Country Code (MCC), Mobile Network Code (MNC), and Tracking Area Code (TAC).

To reduce the times of location update signaling caused by location change, multiple TAs areregistered in a Tracking Area List (TAL). Multiple TAs in a TAL are allocated to a UE so that TA update is not imcamps on the network, the MME determines which TAs are allocated to the UE. When the UE moves to a new TA, which is not in the registered TAL, TA update must be implemented. In this case, the MME allocates another TAL to the UE. The new TAL may contain some TAs in the original TAL.

belonging to the TAs in the TApaging message.

Stratum States Access Stratum (AS) states indicate the connection states between the UE and the eNodeB, which are determined by RRC states. AS states can be classified into idle mode and connecmode according to RRC states.

When a UE is in RRC_IDLE mode, the eNodeB cannot obtain the UE context. In this case, the eNodeB can send System Information (SI) messages and paging m

When a UE needs to communicate with the network for purposes such as service request, location update, and paging, the UE triggers RRC connection establishment. After the RRC connection is established, the UE is in RRC_CONNECTED mode.

3 Related Concepts eRAN



Issue 01 (2010-07-30)

3.3 Non-Access Stratum States NAS states indicate the connection states between the UE and the MME. According to the UE registration state and state of the dedicated S1 connection, NAS states can be classified into the following four states:

z EMM-DEREGISTERED: When the UE does not communicate with the network, the MME cannot obtain the UE context or location information and cannot provide services to the UE. In this case, the UE is in the EPS Mobility Management (EMM) DEREGISTERED state. For example, a powered-off UE is in the EMM-DEREGISTERED state.

z EMM-REGISTERED: When the UE accesses the network, the MME establishes and stores the UE context information and provides services to the UE. In this case, the UE is in the EMM-REGISTERED state. In this state, the MME and UE maintain the TAL information that is stored in the UE.

z ECM-IDLE: When dedicated S1 connection is not established, the NAS signaling connection between the UE and the MME is unavailable. In this case, the UE is in the EPS Connection Management (ECM) IDLE state. In this state, the eNodeB cannot obtain the UE context.

z ECM-CONNECTED: When dedicated S1 connection is established, the NAS signaling connection between the UE and the MME is available. In this case, the eNodeB establishes and stores the UE context information. Thus, the UE is in the ECM-CONNECTED state.

3.4 Call Types in the NAS NAS procedure consists of attach, detach, tracking area update, service request, and extended service request.

During the RRC connection establishment, the RRC Connection Request message contains the cause for the connection establishment. The causes supported in the protocol consist of Mobile Originating (MO)-signaling, MO-data, Mobile Terminating (MT)-access, emergency, and highPriorityAccess.

Call Types in the NAS consist of originating signaling, originating call, terminating call, and emergency call. When a UE in the EMM-IDLE state initiates a NAS message, the UE requests dedicated S1 connection. In this case, the UE selects a cause for RRC connection establishment according to NAS procedure, in which the UE notifies the lower layer of the purpose for the RRC connection. Table 3-1 describes the relations among NAS procedure, call type, and cause for RRC connection establishment.

Table 3-1 Relation between the cause for RRC connection establishment and call type

NAS Procedure Cause for RRC Connection Establishment

Call Type

Attach MO-signaling Originating signaling

Tracking area update MO-signaling Originating signaling

Detach MO-signaling Originating signaling

eRAN Connection Management 3 Related Concepts


3-9

NAS Procedure Cause for RRC Connection Call Type Establishment

MO-data (request for radio resources for service bearer)

Originating call

MO-data (request for resources for uplink signaling)

Originating call

Service request

MT-access (paging response) Terminating call

MO-data (mobile originating CS fallback)

Originating call

MT-access (mobile terminating CS fallback)

Terminating call

Extended service request

Emergency (mobile originating CS fallback emergency call)

Emergency call

After the request for the RRC connection establishment, the cause of which is not MO-data or MO-signaling, is rejected, the UE must wait for some time before sending the request for the RRC connection establishment again. The waiting time can be set through the T302 timer. When the UE receives a rejection message for the RRC connection establishment request, the timer starts. When the UE enters the RRC_CONNECTED mode or cell reselection is performed, the timer stops.

4 Random Access eRAN



Issue 01 (2010-07-30)

4 Random Access RA is performed before a UE begins to communicate with the network. During RA, a UE

em responds to the request and allocates a e RA procedure, the UE can obtain the uplink

ncns

i

z

z z data to a UE

z RC_CONNECTED mode needs to transmit

e TA modification commands from the eNodeB, the UE infers that the UE

Depe e follo

z he access preambles are allocated to UEs by the eNodeB,

d in the Medium Access Control (MAC) layer. Therefore, no corresponding logical channel is

requests access to the system, and then the systRandom Access Channel (RACH). Through thsy hronization signals from the network and request dedicated resources for service data tra mission.

RA s performed in the following scenarios:

Case 1: initial RRC connection establishment. When a UE is changed from RRC_IDLE mode to RRC_CONNECTED mode, the UE initiates RA.

z Case 2: RRC connection reestablishment. When a radio link fails, the UE needs to reestablish RRC connection. In this case, the UE initiates RA. Case 3: handover. When a UE performs handover, the UE initiates RA in the target cell.Case 4: downlink data arrival. When an eNodeB needs to transmit downlinkin RRC_CONNECTED mode and finds that the UE is in the uplink synchronization loss state, the eNodeB instructs the UE to initiate RA. If the uplink timer that is maintained by the eNodeB expires and the eNodeB cannot receive sounding signals from the UE, the eNodeB infers that the UE is in the uplink synchronization loss state. Case 5: uplink data arrival. When a UE in Ruplink data to an eNodeB and finds that it is in the uplink synchronization loss state, the UE initiates RA. If the uplink timer that is maintained by the UE expires and the UE cannot receivis in the uplink synchronization loss state.

nding on whether contention is introduced, the RA procedure can be categorized into thwing types:

z Contention-based RA: The access preambles are generated by UEs, and there may be conflicts among the preambles. Therefore, the eNodeB needs to resolve the contention for UE access. Case 1, case 2, and case 5 are contention-based RA. Non-contention-based RA: Tand each preamble is dedicated to a UE. Therefore, there are no preamble conflicts. When the dedicated preambles that are allocated by the eNodeB are used up, non-contention-based RA becomes contention-based RA. Case 3 and case 4 are non-contention-based RA.

The RACH is used only for the transmission of RA preambles. The preambles are handle

eRAN Connection Management 4 Random Access


4-11

available for the preambles. The Physical Random Access Channel (PRACH) bears the RACH. The PRACH has fixed time and frequency resources, which can be obtained from the common channel configuration parameters in the System Information Block-2 (SIB2).

BFD-002010 Random Access Procedure and dure.

4.1 Random Access Preambles 4.1.1 Overv

E FDD The preamble

and the cell radius can be set through bles in different formats

c n , TSEQ, a cell radii

Table 4-1 Examples of the preambles in different formats

This chapter describes the basic features LTDLBFD-002010 Random Access Proce

iew During the RA procedure of a UE, an eNodeB allocates an RA preamble to the UE. The RApreamble is a burst, which consists of the length of a Cyclic Prefix (CP) CPT and length of a preamble sequence TSEQ in time and involves six resource blocks in frequency.

There are five RA preamble formats, which are used for cells of different radii. LTsupports preamble formats 0-3, and LTE TDD supports preamble formats 0-4. format can be set through the PreambleFmt parameter,the CellRadius parameter. Table 4-1 describes the preamorresponding to differe t TCP nd through examples.

Preamble Format

Burst TCP TSEQ FDD Cell Radius

TDD Cell (R) Radius (R)

0 1,000 s 103.1 s 800 s 4.5 km m < R 14.5 km

R 1 1.4 k

1 2,000 s 684.4 s 800 s m < R 77.3 km

m < R 77.3 km

29 k 29 k

2 2,000 s 203.1 s 1,600 s m < R 29.5 km

m < R 29.5 km

14 k 14 k

3 3,000 s 684.4 s 1,600 s 77 km < R 100 km

77 km < R 100 km

4 167.9 s 14.58 s 133.33 s Not involved. R 1.4 km

By reading prach-ConfigurationIndex in the SIB2, the UE knows the occurrence time of the PRACH in each radio frame. The value of prach-ConfigurationIndex ranges from 0 to 63, and each value contains cell bandwidth, percentage of the occupied uplink resources, number of access times in a second, average access delay, and radio frame and subframe numbers iPRACH. prach-ConfigurationIndex indicates different con

n the tents for the FDD mode and TDD

ges the value ts UE

4.1.2 Pream

mode. For details, see reference document [3]. The eNodeB automatically chanof prach-ConfigurationIndex according to the load on the PRACH. This prevenpreamble conflicts caused by overload on the PRACH.

ble Sequence Generation and Classification The preamble sequence is defined by a cyclic shift of the Zadoff-Chu (ZC) sequence. The logical index of the ZC sequence is determined by RootSequenceIdx, whose value ranges




Issue 01 (2010-07-30)

from 0 to 837. The number of digits for cyclic shifts is determined by the eNodeB accordito the cell type and cell radius. The logical index of the ZC sequence is cyclic. That is, the logical index 0 is consecutive to 837. Each cell can be configured with 64 preamble sequences. If 64 preambles cannot be generated from a single ZC sequence, additional preamble sequences are obtained from the ZC sequences with the consecutive logical indexes until all

ng

ce

fore, the 64 preamble sequences are divided into: random preamble sequence group and ble p

The g counters are periodically collected for the dedicated preamble sequence:

z the

iod arrives, the RACH-related parameters are updated in the broadcast SI messages if the number of preamble sequences changes. The RACH-related parameters consist of the number of random preamble sequences and proportion of random

4.2 Random Access Procedure i a command on the PDCCH. The basic p

1. 2. The U

2 and

es the UE of the PRACH

The contention-based RA procedure is different from the non-contention-based RA procedure. sections. For detailed RA procedures, see

the 64 sequences are found. For details about the preamble sequences generated from cyclic shifts of the ZC sequence, see reference document [3]. The logical index of the ZC sequenand configured cyclic shift value are transmitted in the PRACH configurations in the SIB2.

Based on the contention-based RA and non-contention-based RA, a UE uses the random preamble sequence or dedicated preamble sequence that is allocated by the eNodeB. Therededicated preamble sequence group. To reduce UE preamble conflicts, the random preamsequence groups are divided into preamble sequence group A and preamble sequence grouB.

followin

Maximum number of dedicated preamble sequences that are allocated to the UE inperiod

z Number of preamble sequences in the current dedicated preamble sequence group

Based on the counters, the eNodeB modifies the classification of the dedicated preamble sequence group and random preamble sequence group. In addition, random preamble sequences are evenly divided into group A and group B.

When the SI modification per

preamble sequence group A.

RA s initiated by a UE or starts when a UE receives RA rocedure is as follows:

The UE sets the number of RA attempts to 1. E obtains the PRACH configuration of the serving cell.

For contention-based RA, the UE reads prach-ConfigurationIndex in the SIBobtains the PRACH configuration of the cell.

For non-contention-based RA, the eNodeB notificonfiguration through RRC signaling.

3. The UE transmits an RA preamble to the eNodeB. 4. The eNodeB transmits an RA response to the UE.

The procedures are described in the following reference document [4].



4-13

4.2.1 Conten directly uploads an RA preamble if the PRACH

nf expires or is not specified, the UE must obtai

Whe mble sequence group B is selected if f A is selected if any of the

follo

z The size of the transport block msg3 in the scheduled data transmission is larger than the group A.

z The path loss is smaller than the corresponding threshold.

reamble in the group has an even

tion-Based RA Procedure For contention-based RA, the UEco iguration is specified and does not expire. If it

n the PRACH configuration.

n the UE obtains the PRACH configuration, RA preathe ollowing conditions are met, or RA preamble sequence group

wing conditions is not met:

z Random preamble sequence group B exists.

threshold of random preamble sequence

After a random preamble sequence group is selected, a pprobability to be selected.

Figure 4-1 Contention-based RA procedure

Figure 4-1 shows the contention-based RA procedure. The procedure is divided into four stepUE transmitting an RA preamble, eNodeB transmitting an RA response, UE transmitting uplink scheduled data, and eNodeB transmitting a contention resolution.

s:

UE Transmittie

transmit power of a preamble P , see the Power Control Feature Parameter Description.

ated, the UE transmits a preamble with the transmit

eNodeB Trans

the Downlink Shared Channel (DL-SCH). The response contains RA-Preamble Identifier,

ng an RA Preamble The UE transmits an RA preamble over the PRACH. For details about the calculation of th

PRACH

On the following PRACH that is allocpower of PPRACH. The preamble usually carries information of six bits, in which five bits indicate the Random Access Radio Network Temporary Identifier (RA-RNTI), and one bit indicates the size of the uplink transport block msg3 in the scheduled data transmission.

mitting an RA Response Upon receiving the UE preamble, the eNodeB applies for Temporary Cell RNTI (C-RNTI) and uplink and downlink scheduling resources. The eNodeB transmits an RA response over




Issue 01 (2010-07-30)

Tim ng Alignment Information, Initial UL Grant, and Temporary C-RNTI. A message onCH can carry multiple RA responses to be transmitted to multiple UEs.

i the DL-S

Once t l

z

z If the UE does not receive a response within the TTI, or if all received RA responses at do not match the transmitted RA preamble, the UE

Then, the UE performs RA again if the number of

UE Transmitti UThe whic

cording to the RA scenario.

z LC

z

t carried in the message. z during a handover procedure without a

C-RNTI are transmitted over the DCCH, and also carried.

eNodeB Trans

successfully resolved, the contention-based RA procedure ends.

tion timer starts.

resol situa

MAC Packet Data Unit (MAC PDU) is successfully decoded.

If the contention resolution timer expires, the UE infers that the contention resolution fails. Then, the UE performs RA again if the number of RA attempts is smaller than the maximum number of attempts. If the number of RA attempts is not smaller, the RA procedure fails.

he preamble is transmitted, the UE monitors the Physical Dedicated Control Channe(PDCCH) in the Transmission Time Interval (TTI) until it obtains the required RA response.

If the received RA-Preamble Identifier is consistent with the identifier that the UE previously sent, the UE infers that the response is successful. Then, the UE transmitsuplink scheduled data.

contain RA preamble identifiers thinfers that the response reception fails.RA attempts is smaller than the maximum number of attempts. If the number of RA attempts is not smaller, the RA procedure fails.

ng plink Scheduled Data UE transmits uplink scheduled data over the UL-SCH. The size of the transport block, h is not smaller than 80 bits, is specified in the preamble. The carried signaling and

information in the transport block vary ac

Initial RRC connection establishment RThe RRC Connection Request message is transmitted over the CCCH in TM in the

layer. NAS UE_ID is carried in the message, and the message is not segmented. RRC connection reestablishment The RRC Connection Reestablishment message is transmitted in TM in the RLC layer.

t segmented, and the NAS message is noThe message is noTarget cell access that is contention-based dedicated RA preamble The RRC Handover Confirm message andif required, Buffer Status Report (BSR) is

z Other scenarios At least C-RNTI of the UE is transmitted.

mitting a Contention Resolution The contention resolution is generated in the RRC layer. Then, the eNodeB transmits the contention resolution to the UE through the CCCH or DCCH over the DL-SCH. If the contention is

If the UE receives the contention resolution, the contention resolu

The UE monitors the PDCCH before the timer expires. The UE infers that the contention ution is successful, and it notifies the upper layer and stops the timer in the followingtions:

z The UE obtains the C-RNTI when monitoring the PDCCH. z Messages transmitted over the CCCH are contained in the uplink message, and

Temporary C-RNTI is obtained when the UE monitors the PDCCH. In addition, the



4-15

4.2.2 Non-Contention-Based RA Procedure Compared with the contention-based RA procedure, the non-contention-based RA procedure does not have the contention and conflict resolution steps because the RA preamble is allocated by the eNodeB. Figure 4-2 shows the non-contention-based RA procedure.

Figure 4-2 Non-contention-based RA procedure

The non-contention-based RA procedure is as follows:

1. The eNodeB allocates an RA preamble to the UE in dedicated signaling. During handover, the HO COMMAND message transmitted by the source eNodeB

carries an allocated preamble. Upon downlink data arrival, the signaling in the MAC layer carries an allocated

preamble. 2. Over the RACH, the UE transmits the dedicated preamble that is allocated. 3. The eNodeB transmits an RA response over the DL-SCH.

During handover, at least Timing Alignment Information and Initial UL Grant are contained in the RA response.

Upon downlink data arrival, at least Timing Alignment Information and RA-Preamble Identifier are contained in the RA response.

4.3 RA Backoff Control In the LTE system, the RACH does not cause any interference to other uplink channels. Therefore, the LTE system has lower overload control requirement than earlier mobile communications systems. Generally, the probability of RACH collision is low. If excessive UEs are admitted on a PRACH, however, UE preamble conflict may occur, and some UEs fail to access the network. To reduce the conflict probability, backoff control is introduced in the LTE system to control the time for the UE to retransmit preambles.

The eNodeB notifies the UE of a backoff value through the RA response. If retransmission is required, the UE selects a value between 0 and the received backoff value as its backoff time. After the backoff time ends, the UE retransmits the preamble. In the following two cases, however, the backoff control is not implemented:

z During the initial preamble transmission




Issue 01 (2010-07-30)

z In non-contention-based RA

The eNodeB records the current RACH overload counter. The initial backoff value is 0. When the RACH is overloaded, the backoff value is increased by 1. The action continues if the RACH is still overloaded. If the backoff value is equal to the maximum value and the RACH is still overloaded, the PRACH configuration needs to be modified. That is, the number of PRACHs is increased, and the backoff value is set to 0. When the RACH is underloaded, the backoff value is decreased by 1. The action continues if the RACH is still underloaded. If the backoff value is equal to the minimum value and the RACH is still underloaded, the PRACH configuration needs to be modified. That is, the number of PRACHs is decreased, and the backoff value is set to 0. If the RACH is neither overloaded nor underloaded, the backoff value remains unchanged.

eRAN Connection Management 5 Signaling Connection Processing


5-17

5 Signaling Connection Processing Signaling connection consists of RRC connection on the Uu interface and dedicated S1 connection. Generally, signaling connection is established for the establishment of the sebearer connection. In certain scenarios, however, signaling connection is used only for the signaling procedure (such as UE location update), but not for the service bearer connection.

rvice

Signaling connection processing involves the establishment of the signaling connection nd service bearer ME. Figure 5-1 shows

stem.

between the UE and the MME, release of the signaling connection aconnection, and NAS message processing between the UE and the Mthe architecture of the protocol stack for signaling connection in the LTE sy

Figure 5-1 Architecture of the protocol stack for signaling connection

2007 RRC Connection Management and

5.1 RRC C

the Evolved Packet establishment does not need

ted for the SRB1. During

This chapter describes the basic features LBFD-00TDLBFD-002007 RRC Connection Management.

onnection Establishment RRC connection, which is initiated by the UE, is Layer 3 connection between the UE and theeNodeB. RRC connection establishment is a procedure for establishing the SRB1. Before the S1 connection is established, the UE context cannot be obtained fromCore (EPC). Therefore, the security during the RRC connection to be activated, and encryption and integrity protection are not star

5 Signaling Connection Processing eRAN



Issue 01 (2010-07-30)

the RRC connection establishment, the UE can be configured to perform measurements. The UE can perform handover only when the security mode is started.

Figure 5-2 shows the RRC connection establishment procedure.

Figure 5-2 RRC connection establishment procedure

connection establishment procedure is as follows:

1. sage

The RRC

Over the CCCH, the UE sends the eNodeB the RRC Connection Request mescontaining the cause for the RRC connection establishment. For details about the cause for the RRC connection establishment, see section 3.4 "Call Types in the NAS".

NOTE UE_ID is contained in the RRC Connection Request message. If the upper layer provides the SAE Temporary Mobile Station Identifier (S-TMSI), the UE sends the message containing the S-TMSI to the

the message t need to

a

2. me

4.

5. urce configuration after receiving the RRC Connection Setup message containing the SRB1 resource information, and then the UE sends the eNodeB

message. mplete message, the RRC

eNodeB. If the upper layer does not provide the S-TMSI, the UE sends the eNodeBcontaining a random value ranging from 0 to 240 - 1. In the LTE system, the eNodeB does noobt in the IMSI information of the UE.

The eNodeB establishes the UE context after receiving the RRC Connection Requestssage.

3. The eNodeB performs the SRB1 resource admission and allocation. All signaling connections are admitted without any judgment. If resource allocation fails, the eNodeB responds to the UE with an RRC Connection

Reject message. If resource allocation is successful, the subsequent steps proceed. The eNodeB responds to the UE with an RRC Connection Setup message over the CCCH. The message contains detailed information about the SRB1 resource configuration. The UE performs radio reso

the RRC Connection Setup Complete message containing the NAS 6. After the eNodeB receives the RRC Connection Setup Co

connection is established.



5-19

5.2 DedicaE and the eNodeB and

dedicated S1 connection between the eNodeB and the MME. After receiving the RRC MME the Initial UE Message

containing the NAS message to start dedicated S1 connection establishment. Figure 5-3

ted S1 Connection Establishment Signaling connection consists of RRC connection between the U

Connection Setup Complete message, the eNodeB sends the

shows the dedicated S1 connection establishment procedure.

Figure 5-3 Dedicated S1 connection establishment procedure

dedicated S1 connection establishment procedure is as follows:

The

ving the RRC Connection Setup Complete message, the eNodeB allocates a

1. After receidedicated S1APID to the UE. Then, the eNodeB encapsulates the NAS message that isoriginally contained in the RRC Connection Setup Complete message and S1APID in the Initial UE Message before forwarding the Initial UE Message to the MME.

NOTE This document does not describe how to select an MME when an eNodeB connects to multiple MMEs. For details, see the S1-Flex Feature Parameter Description.




Issue 01 (2010-07-30)

2. The MME parses the NAS message contained in the Initial UE Message before obtaining the cause for the connection establishment. Then, the MME handles the UE service request based on the cause and allocates a dedicated S1APID to the UE.

MME sends the eNodeB the Initial Context Setup Request message, which may

4.

arameters.

NO

3. Thecontain the common UE context and EPS bearer context. After receiving the Initial Context Setup Request message, the eNodeB starts the UEcontext establishment. At the same time, the eNodeB generates security keys for service bearer and signaling based on the received security p

TE By comparing the eNodeB-supported algorithms with the UE-supported algorithms, the eNodeB selects a security algorithm supported by both the eNodeB and the UE and then sends the algorithm to the UE through the Security Mode Command message. This document does not describe the security procedure.

5. 6. cts the UE to start integrity protection and encryption when sending

7.

arted. n E

ishment parameter are transmitted together. The security procedure must be started by the eNodeB first. The service

d later before the security procedure is n message in 7 can be sent before the Thus, the delay from the initial UE

5.3 RRC C

n reestablishment.

ts

e the UE context information, the UE will be rejected

For details, see the Security Feature Parameter Description.

The eNodeB performs service admission decision and resource allocation. The eNodeB instruthe UE the security keys through the Security Mode Command message. At the moment, downlink encryption is started. The eNodeB sends the UE the RRC Connection Reconfiguration message on which encryption and integrity protection is performed. This is used for the establishment of the SRB2 and DRB.

8. After receiving the Security Mode Command message from the eNodeB, the UE selects an encryption algorithm provided by the eNodeB. After the security keys that are used by both the service bearer and the signaling are successfully generated, the UE transmitsthe Security Mode Complete message, which is not encrypted. After the eNodeB receives the Security Mode Complete message, uplink encryption is st

9. The UE establishes corresponding resources according to the RRC ConnectioReconfiguration message. After the resources are successfully established, the Uresponds to the eNodeB with an RRC Connection Reconfiguration Complete message.

10. The eNodeB sends the MME the feedback through the Initial Context Setup Responsemessage, which indicates that the bearer is successfully established.

The E-UTRAN integrates the security procedure and initial bearer establishment procedure, which indicating that the security parameter and bearer establ

bearer establishment procedure, however, can be startecomplete. That is, the RRC Connection ReconfiguratioUE responds with a Security Mode Complete message.access to the bearer establishment is significantly reduced.

onnection Reestablishment RRC connection involves the SRB1 reestablishment and security reactivation. A UE in RRC_CONNECTED mode, whose security is activated, can initiate RRC connection reestablishment for resuming RRC connection. RRC connection reestablishment can be triggered in the case of a handover failure, RRC reconfiguration failure, or radio link failure. If security in the AS is not activated, a UE cannot initiate RRC connectio

A UE may be admitted for RRC connection reestablishment by a cell only if the UE requesRRC connection reestablishment in the cell that served by an eNodeB having the UE context information. If the eNodeB does not hav



5-21

on RRC connection reestablishment. After the RRC connection is successfully reestablished, the SRB1 can be resumed, whereas other bearers cannot be resumed.

he eNodeB reconfigures the SRB1, rity in the AS without

When handling the RRC connection reestablishment, tresumes data transmission on the service bearer, and reactivates the secumodifying the security algorithm.

Figure 5-4 shows the RRC connection reestablishment procedure.

Figure 5-4 RRC connection reestablishment procedure

The RR

1. R

acc

The eNodeB decides whether the UE context information is available based on C-RNTI

C connection reestablishment procedure is as follows:

The UE sends the RRC Connection Reestablishment Request message. The cause for theR C connection reestablishment and cell information contained in the message varies

ording to the scenario. The cause for the RRC connection reestablishment triggered by a reconfiguration

failure is reconfigurationFailure. C-RNTI and physCellId in the cause are the information of the serving cell.

The cause for the RRC connection reestablishment triggered by a handover failure is handoverFailure. C-RNTI and physCellId in the cause are the information of the source cell.

The cause for the RRC connection reestablishment triggered by a radio link failure is otherFailure. C-RNTI and physCellId in the cause are the information of the serving cell.

2. and physCellId. If the UE context information is available, the eNodeB verifies the security parameters. If the security parameter verification information in the UE is consistent with that in the eNodeB, the verification of the UE is successful. After the verification, the eNodeB releases the earlier resources and then performs admission and resource allocation again.

NOTE If the UE fails to be verified, the eNodeB rejects the RRC connection reestablishment request of the UE.




Issue 01 (2010-07-30)

3. Over the CCCH, the eNodmessage, which contains the i

eB sends the UE the RRC Connection Reestablishment nformation of the allocated resources. After receiving the

resources ity

5.4 Signalited S1 connection and RRC

connection. RRC connection release consists of the release of the signaling link and all the iated by the

plete or a UE command. If e MME.

RRC Connection Reestablishment message, the UE reconfigures radio according to the instructions in the message and then starts encryption and integrprotection.

4. The UE sends the eNodeB the RRC Connection Reestablishment Complete message.

ng Link Release Signaling link release involves the release of the dedica

radio bearers between the UE and the eNodeB. Signaling link release can be initMME or eNodeB. If service between the UE and the MME in the NAS is comdecides to stop the service, the MME sends the eNodeB a signaling link release an exception is detected, the eNodeB sends a signaling link release request to th

Figure 5-5 shows the signaling link release procedure.

Figure 5-5 Signaling link release procedure

signaling link release procedure is asThe follows:

ME a UE Context Release

1. The signaling link release is initiated in the following two scenarios: The MME initiates a UE Context Release Command message. After detecting an exception, the eNodeB sends the M

Request message. Then, the eNodeB must wait until the MME sends a UE Context Release Command message.



5-23

2. The eNodeB releases transmission resources and triggers the release of the RRC connection over the Uu interface. The eNodeB sends th3. e UE an RRC Connection Release message to release the resources

se

t

the

The eNodeB monitors the UE for data transmission or reception when the timer set through the UeInactiveTimer parameter does not expire. When the timer expires, the eNodeB sends the MME the signaling link release request if the UE fails to receive or send data.

When the MME initiates load rebalancing, the relative capacity of the MME should be reconfigured, and the result must be sent to the eNodeB. In this case, the eNodeB does not select the MME for the RRC connection establishment. If the RRC connection is released due to load rebalancing, the eNodeB redirects the UE to another cell in the LTE system or a cell in another Radio Access Technology (RAT) system.

over the Uu interface. In this case, the eNodeB does not need to wait for the responfrom the UE.

4. The eNodeB releases the radio resources in the system. 5. The eNodeB sends the MME the UE Context Release Complete message, indicating tha

the resource release is complete. 6. After sending the UE Context Release Complete message, the eNodeB releases

corresponding UE context. Thus, the UE is changed from RRC_CONNECTED mode to RRC_IDLE mode.

To release all the S1 resources including the service bearer resources, the MME can release the dedicated S1 connection.

6 RB Management eRAN



Issue 01 (2010-07-30)

6 RB Management RB management refers to the management of the SRB2 and DRB after the encryption and

tion

on procedure. Therefore, RB management does not require dedicated signaling. RRC reconfiguration is used in scenarios such as establishment, modification, and release of

t ish RRC reconfiguration messages in different

scenarios.

Bearer Management and

6.1 SRB2 Establishment and Modification

on

ing Packet Data Convergence Protocol

The SRB2 is modified only when the related configuration information is changed. The SRB2 can be modified and established through the same RRC Connection Reconfiguration message. Upon receiving the message, the UE reconfigures the corresponding PDCP entity, RLC entity, and DCCH. Figure 6-1 shows the SRB2 modification procedure.

integrity protection is complete. RB management involves the establishment and modificaof the SRB2 and DRB and also release of the DRB. The SRB2 is released with the SRB1 during signaling link release. For details about the signaling link release, see section 5.4 "Signaling Link Release".

In RB management, the interaction between the UE and the eNodeB is based on the RRC reconfigurati

RBs and configuration and modification of handover measurement information. DifferenInformation Elements (IEs) are used to distingu

This chapter describes the basic features LBFD-002008 Radio TDLBFD-002008 Radio Bearer Management.

The UE is notified of the establishment and modification of the SRB2 through the RRC reconfiguration message.

The SRB2 establishment is implemented after the encryption and integrity protection are complete during the dedicated S1 connection establishment. srb-ToAddModList contained inthe RRC Connection Reconfiguration message instructs the UE to establish the SRB2. Upreceiving the message, the UE establishes a correspond(PDCP) entity and configures the related security parameters, establishes an RLC entity and configures related parameters, and establishes a DCCH and configures the logical channel. The SRB2 establishment signaling procedure and dedicated S1 connection establishment procedure are the same. For details, see Figure 5-3.

eRAN Connection Management 6 RB Management


6-25

Figure 6-1 SRB2 modification procedure

6.2 DRB Establishment and Modification The DRB is established after encryption and integrity protection is complete. After the UE context is established, the DRB establishment can be triggered by the E-RAB Setup Request message sent from the MME. drb-ToAddModList which is originally contained in the Radio Resource Config Dedicated message is contained in the RRC Connection Reconfiguration message. According to the instructions contained in the message, the UE establishes a corresponding PDCP entity and configures the related security parameters, establishes an RLC entity and configures related parameters, and establishes a DTCH and configures the logical channel. Figure 6-2 shows the DRB establishment signaling procedure.

Figure 6-2 DRB establishment procedure

6 RB Management eRAN



Issue 01 (2010-07-30)

The DRB modification is triggered by the MME through the E-RAB Modify Request message. Figure 6-3 shows the DRB modification procedure. According to the instructions in the RRC Connection Reconfiguration message, the UE reconfigures the corresponding PDCP entity, corresponding RLC entity, and DCCH.

Figure 6-3 DRB modification procedure

6.3 DRB Release The DRB may be released by the E-RAB Release Command message sent from the MME or with the signaling link. During the DRB release, drb-ToReleaseList that is originally contained in the Radio Resource Config Dedicated message is contained in the RRC Connection Reconfiguration message. Upon receiving the message, the UE releases all the corresponding DRB resources. Figure 6-4 shows the DRB release procedure.

eRAN Connection Management 6 RB Management


6-27

Figure 6-4 DRB release procedure

7 Engineering Guidelines eRAN



Issue 01 (2010-07-30)

7 Engineering Guidelines This chapter provides engineering guidelines regarding the connection management.

7.1 T302 ates the waiting time for resending the RRC connection establishment

e

If the T302 is set to a large value, the UE does not access the cell in a long period of time re the user experience is affected. If the T302 is set to a small value, the network repeatedly, resulting in heavy loads in the system.

7.2 RA CoThe RA

jusswitcswitc

z ces in the preamble sequence group of

z ts based on the RA preamble sequence detection result. If the

The T302 timer indicrequest after the RRC connection establishment request initiated by the UE is rejected. Thcause of the RRC connection establishment request is neither MO-data nor MO-signaling. The T302 can be set to a large value for a cell with heavy traffic or a small value for a cell with light traffic.

after rejected, and therefothe UE attempts to access

nfigurations algorithm switch consists of the preamble group adjustment switch, time resource

ad tment switch, non-contention-based RA switch for handover, non-contention-based RA h for synchronization, dedicated preamble multiplexing switch, and backoff control h. The switch is controlled by the RachAlgoSwitch parameter.

Preamble group adjustment switch (RaGrpAdjSwitch): RaGrpAdjSwitch adaptively adjusts the number of dedicated preamble sequenthe cell. If the switch is turned on, the algorithm dynamically adjusts the preamble configurations according to the use of the preambles. If the switch is turned off, the algorithm uses the initial configuration and does not perform dynamic adjustment. It is recommended that the parameter is set to OFF. Time resource adjustment switch (RaTrAdjSwitch): RaTrAdjSwitch adaptively adjusthe PRACH configurations switch is turned on, the algorithm dynamically adjusts the time resource configuration according to the RACH load. If the switch is turned off, the algorithm uses the initial configuration and does not perform dynamic adjustment. It is recommended that the parameter is set to OFF.

eRAN Connection Management 7 Engineering Guidelines


7-29

z Non-contention-based RA switch for handover (HoRaSwitch): This parameter cothe selection of the RA methods during handover. If the switch is turned on, the eNodeBinstructs the UE to perform non-contention-based RA during handover. If the switch iturned off, the eNodeB instructs the UE to perform contention-based RA during handover. It is recommended that the parameter is set to ON. Non-contention-based RA switch for synchronization (UnsyncRaSwitch): This parameter controls the selec

ntrols

s

z tion of the RA methods during the uplink synchronization

es. RA

ls

d

z tively adjusts the backoff time based on the load on the RACH. Thus, the congestion on the RACH is relieved. If the switch is turned on, the RA backoff algorithm dynamically adjusts the backoff time for the UE to retransmit the preambles according to the number of RA preambles detected on each PRACH. If the switch is turned off, RA backoff is not performed. It is recommended that the parameter is set to OFF.

loss of the UE. If the switch is turned on, the eNodeB instructs the UE to perform non-contention-based RA when the synchronization is lost and the downlink data arrivIf the switch is turned off, the eNodeB instructs the UE to perform contention-based when the synchronization is lost and the downlink data arrives. It is recommended that the parameter is set to ON.

z Dedicated preamble multiplexing switch (MaksIdxSwitch): This parameter controwhether dedicated preambles are used for multiplexing between different UEs. If the switch is turned on, the eNodeB uses the same dedicated preamble for multiplexing between different UEs. If the switch is turned off, the eNodeB allocates one dedicatepreamble to only one UE. It is recommended that the parameter is set to OFF. Backoff control switch (BackOffSwitch): BackOffSwitch adap

eRAN Connection Management 8 Parameters

01 (2010-07-30) Huawei Proprietary and Confidential Copyright Huawei Technologies Co., Ltd.

8-1

8 Parameters This chapter describes the parameters related to connection management.

For the meaning of each parameter, see Table 8-1. For the default value, value ranges, and MML commands of each parameter, see Table 8-2.

8 Parameters eRAN



Issue 01 (2010-07-30)

Table 8-1 Parameter description (1)

MO Parameter ID Description

CellAlgoSwitch

RachAlgoSwitch RaGrpAdjSwitch: Indicates the switch that is used to enable and disable the group adjustment algorithm. When this switch is set to ON, the algorithm dynamically adjusts the preamble configuration based on the preamble usage. When this switch is set to OFF, the algorithm uses the initial configuration and does not perform dynamic adjustments. RaTrAdjSwitch: Indicates the switch that is used to enable and disable the time-domain resource adjustment algorithm. When this switch is set to ON, the algorithm dynamically adjusts the time-domain resource allocation based on the load on the RACH. When this switch is set to OFF, the algorithm uses the initial configuration and does not perform dynamic adjustments. HoRaSwitch: Indicates the switch that is used to control the random access mode applied during handovers. When this switch is set to ON, the eNodeB instructs UEs to use the non-contention-based random access mode during handovers. When this switch is set to OFF, the eNodeB instructs UEs to use the contention-based random access mode during handovers. UnsyncRaSwitch: Indicates the switch that is used to control the random access mode applied when UEs are out of synchronization in the uplink. When this switch is set to ON, the eNodeB instructs UEs to use the non-contention-based random access mode upon DL data arrival in the case of out-of-synchronization. When this switch is set to OFF, the eNodeB instructs the UE to use the contention-based random access mode upon DL data arrival in the case of out-of-synchronization. MaksIdxSwitch: Indicates the switch that is used to control the reuse of dedicated preambles between UEs. When this switch is set to ON, the eNodeB enables reuse of dedicated preambles between UEs based on the MaskIndex parameter. When this switch is set to OFF, the eNodeB allocates one dedicated preamble to only one user at a given time. BackOffSwitch: Indicates the switch that is used to enable and disable the backoff control algorithm. When this switch is set to ON, the backoff control algorithm is enabled. When this switch is set to OFF, the backoff control algorithm is disabled.

Cell RootSequenceIdx Indicates the logical root sequence index, which is used to derive the preamble sequence. Each logical root sequence corresponds to a physical root sequence. For the mapping between logical root sequences and physical root sequences, see 3GPP TS 36.211.

Cell PreambleFmt Indicates the preamble format used in the cell. For details, see 3GPP TS 36.211.

Cell CellRadius Indicates the radius of the cell.

eRAN Connection Management 8 Parameters


8-3

MO Parameter ID Description

RRCConnStateTimer

T302 Indicates the length of timer T302. It refers to the wait time for retransmitting an RRCConnectionRequest message after the previous request with a cause other than "MO-Data" and "MO-Signalling" is rejected. This timer is started after the UE receives the RRCConnectionReject message. This timer is stopped when the UE enters the RRC_CONNECTED mode or performs cell reselection.

RRCConnStateTimer

UeInactiveTimer Indicates the time threshold that specifies when an idle UE should be disconnected from the network. The eNodeB monitors whether UEs are receiving or sending data. When a UE has neither received nor sent data for a duration exceeding this threshold, the eNodeB releases the radio resources of the UE. When this parameter is set to 0, the eNodeB does not monitor the data transmitting or receiving state of the UE.

Table 8-2 Parameter description (2)

MO Parameter ID

Default Value

GUI Value Range

Actual Value Range

Unit MML Command

CellAlgoSwitch

RachAlgoSwitch

RaGrpAdjSwitch:Off, RaTrAdjSwitch:Off, HoRaSwitch:On, UnsyncRaSwitch:On, MaksIdxSwitch:Off, BackOffSwitch:Off

RaGrpAdjSwitch(RaGrpAdjSwitch), RaTrAdjSwitch(RaTrAdjSwitch), HoRaSwitch(HoRaSwitch), UnsyncRaSwitch(UnsyncRaSwitch), MaksIdxSwitch(MaksIdxSwitch), BackOffSwitch(BackOffSwitch)

RaGrpAdjSwitch, RaTrAdjSwitch, HoRaSwitch, UnsyncRaSwitch, MaksIdxSwitch, BackOffSwitch

None MOD CELLALGOSWITCH

Cell RootSequenceIdx

None 0~837 0~837 None ADD CELL MOD CELL

Cell PreambleFmt

0 0~4 0~4 None ADD CELL MOD CELL

Cell CellRadius 10000 1~100000 1~100000 m ADD CELL MOD CELL

RRCConnStateTimer

T302 4 1~16 1~16 s MOD RRCCONNSTATETIMER LST RRCCONNSTATETIMER

8 Parameters eRAN



Issue 01 (2010-07-30)

MO Parameter Default GUI Value Actual Value Unit MML ID Value Range Range Command

RRCConnStateTimer

UeInactiveTimer

1800 0~3600 0~3600 s MOD RRCCONNSTATETIMER LST RRCCONNSTATETIMER

eRAN Connection Management 9 Counters


9-1

9 Counters For details about the counters related to connection management, see the eNodeB Performance Counter Reference.

10 Glossary eRAN



Issue 01 (2010-07-30)

10 Glossary 10.1 Terms

10.2 Acronyms and Abbreviations e

ss Bearer

ing System

nt Entity

e

ing

hannel

ss

TI Identifier

None.

AM Acknowledged Mod

AS Access Stratum

DRB Data Radio Bearer

EPS Evolved Packet System

E-RAB E-UTRAN Radio Acce

ETWS Earthquake and Tsunami Warn

MCC Mobile Country Code

MME Mobility Manageme

MNC Mobile Network Cod

MO Mobile Originating

MT Mobile Terminat

NAS Non-Access Stratum

P-GW PDN-Gateway

PRACH Physical Random Access C

RA Random Acce

RACH Random Access Channel

RB Radio Bearer

RN Radio Network Temporary

eRAN Connection Management 10 Glossary


10-3

S-GW

er

tity

TAL Tracking Area List

TM Transparent Mode

Serving Gateway

SI System Information

SRB Signaling Radio Bear

TA Tracking Area

TAC Tracking Area Code

TAI Tracking Area Iden

11 Reference Documents eRAN



Issue 01 (2010-07-30)

11 Reference Documents This chapter lists the reference documents related to connection management.

[1] 3GPP TS 36.331, "Radio Resource Control (RRC); Protocol specification"

Evolved

odulation"

m Access Control (MAC) protocol specification"

] S1-Flex Feature Parameter Description

[9] Power Control Feature Parameter Description

[2] 3GPP TS 23.401, "General Packet Radio Service (GPRS) enhancements forUniversal Terrestrial Radio Access Network (E-UTRAN) access"

[3] 3GPP TS 36.211, "Physical channels and m

[4] 3GPP TS 36.321, "Mediu

[5] eNodeB Performance Counter Reference

[6] eNodeB MO Reference

[7] Security Feature Parameter Description

[8

1 Introduction 1.1 Scope 1.2 Intended Audience 1.3 Change History

2 Overview of Connection Management 2.1 Random Access 2.2 UE Connection 2.2.1 Signaling Connection 2.2.2 RB Management

3 Related Concepts 3.1 Tracking Area 3.2 Access Stratum States 3.3 Non-Access Stratum States 3.4 Call Types in the NAS

4 Random Access 4.1 Random Access Preambles 4.1.1 Overview 4.1.2 Preamble Sequence Generation and Classification

4.2 Random Access Procedure 4.2.1 Contention-Based RA Procedure 4.2.2 Non-Contention-Based RA Procedure

4.3 RA Backoff Control

5 Signaling Connection Processing 5.1 RRC Connection Establishment 5.2 Dedicated S1 Connection Establishment 5.3 RRC Connection Reestablishment 5.4 Signaling Link Release

6 RB Management 6.1 SRB2 Establishment and Modification 6.2 DRB Establishment and Modification 6.3 DRB Release

7 Engineering Guidelines 7.1 T302 7.2 RA Configurations

8 Parameters 9 Counters 10 Glossary 10.1 Terms 10.2 Acronyms and Abbreviations

11 Reference Documents

Connection Management Feature Parameter Description(ERAN2.0_01)

Documents

Transcript of Connection Management Feature Parameter Description(ERAN2.0_01)