15-Iu Flex

RAN Feature Description Table of Contents

Table of Contents

Chapter 15 Iu Flex...................................................................................................................... 15-1

15.1 Introduction to Iu Flex..................................................................................................15-1

15.1.1 Definition...........................................................................................................15-1

15.1.2 Purposes...........................................................................................................15-1

15.1.3 Benefits.............................................................................................................15-1

15.1.4 Terms and Abbreviations...................................................................................15-2

15.2 Availability....................................................................................................................15-3

15.2.1 Network Element Involved.................................................................................15-3

15.2.2 Software Release..............................................................................................15-3

15.2.3 Miscellaneous....................................................................................................15-4

15.3 Impact.......................................................................................................................... 15-4

15.3.1 On the System Performance.............................................................................15-4

15.3.2 On Other Features.............................................................................................15-4

15.4 Technical Description...................................................................................................15-4

15.4.1 Iu Flex Configuration Model...............................................................................15-4

15.4.2 Pool Area...........................................................................................................15-4

15.4.3 NRI....................................................................................................................15-6

15.4.4 NNSF.................................................................................................................15-7

15.4.5 Load Balancing and Flow Control....................................................................15-11

15.4.6 Support of the RNC on the Iu Flex...................................................................15-12

15.4.7 Impact on Signaling Procedures......................................................................15-12

15.5 Capabilities................................................................................................................15-13

15.6 Implementation..........................................................................................................15-13

15.6.1 Enabling Iu Flex...............................................................................................15-13

15.6.2 Reconfiguring Iu Flex Parameters...................................................................15-15

15.6.3 Disabling Iu Flex..............................................................................................15-15

15.7 Maintenance Information............................................................................................15-16

15.7.1 MML Commands Related to Iu Flex................................................................15-16

15.7.2 Alarms.............................................................................................................15-16

15.7.3 Counters..........................................................................................................15-16

15.8 References................................................................................................................. 15-17

Huawei Technologies Proprietary

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RAN Feature Description List of Figures

List of Figures

Figure 15-1 Iu Flex function diagram..................................................................................15-1

Figure 15-2 Iu Flex configuration model..............................................................................15-4

Figure 15-3 Pool area configuration example.....................................................................15-5


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RAN Feature Description List of Tables

List of Tables

Table 15-1 NEs required for Iu Flex.....................................................................................15-3

Table 15-2 Data negotiated for the Iu Flex........................................................................15-14


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RAN Feature Description Chapter 15 Iu Flex

Chapter 15 Iu Flex

15.1 Introduction to Iu Flex

15.1.1 Definition

The Iu Flex enables the connection of one node on the Radio Access Network (RAN)

to multiple nodes on the Core Network (CN) and the collection of one or more RAN

nodes into a pool area, as shown in Figure 15-1. In the same pool area, a UE roams

without need to change the serving CN node.

CS3

RNC

NodeB

PS2CS2CS1

PS1 PS3

Figure 15-1 Iu Flex function diagram

The Iu Flex involves the following concepts:

Pool Area

NRI

NNSF

15.1.2 Purposes

Before Iu Flex is introduced, one RAN node can be connected to only one CN node.

This brings a lot of inconvenience to network construction, for example, the

unbalanced signaling load on CN nodes. The load on some CN nodes is light, which

leads to low hardware usage, while the load on some other CN nodes is heavy, which

causes the CPU to work busily.

15.1.3 Benefits

The Iu Flex brings the following benefits:

Enhancing the flexibility of the Iu interface

Increasing the total capacity of CN nodes


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Enhancing the disaster tolerance capability of CN nodes

Reducing the signaling traffic of the CN

Enhancing the system utilization

In conclusion, the Iu Flex greatly enhances the serviceability of the whole network.

15.1.4 Terms and Abbreviations

I. Terms

Term Description

Iu Flex Intra Domain Connection of RAN Nodes to Multiple CN Nodes

CN node Node of the CN

II. Abbreviation

Abbreviation Full Spelling

3GPP Third Generation Partnership Project

BAM Back Administration Module

CN Core Network

CS Circuit Switched

FTP File Transfer Protocol

HLR Home Location Register

IDNNS Intra Domain NAS Node Selection

IE Information Element

IMEI International Mobile Equipment Identity

IMSI International Mobile Subscriber Identity

LA Location Area

LAI Location Area Identity

LMT Local Maintenance Terminal

MCC Mobile Country Code

MML Man Machine Language


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Abbreviation Full Spelling

MNC Mobile Network Code

MSC Mobile Switching Center

NAS Non-Access Stratum

NE Network Element

NNSF Non Access Stratum (NAS) Node Selection Function

NRI Network Resource Identifier

OMC Operation and Maintenance Center

PLMN Public Land Mobile Network

PS Packet Switched

P-TMSI Packet Temporary Mobile Subscriber Identity

RA Routing Area

RAI Routing Area Identity

RAN Radio Access Network

RANAP Radio Access Network Application Part

RNC Radio Network Controller

RRC Radio Resource Control

SGSN Serving GPRS Support Node

SIM Subscriber Identity Module

TMSI Temporary Mobile Subscriber Identity

UE User Equipment

USIM Universal Subscriber Identity Module

15.2 Availability

15.2.1 Network Element Involved

Table 15-1 describes the NEs involved with the Iu Flex feature.


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Table 15-1 NEs required for Iu Flex

UE NodeB RNC MSC Server MGW SGSN GGSN HLR

√ – √ √ – √ – –

Note:

–: not required

√: required

15.2.2 Software Release

This feature is available for BSC6800 V100R005 and later releases.

15.2.3 Miscellaneous

None.

15.3 Impact

15.3.1 On the System Performance

None.

15.3.2 On Other Features

None.

15.4 Technical Description

15.4.1 Iu Flex Configuration Model

The configuration model for Iu Flex is as show in Figure 15-2.


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RNC

RadioClass

GlobalParaClass OtherClass

IUFLEX .Class

Length of PS NRI in bits

NRIGLBCNIDMAP .Class

Network resource identity

IMSIIDNNSCNIDMAP .Class

Minimum of IMSI routeparameter in IDNNS

Length of CS NRI in bits Maximum of IMSI routeparameter in IDNNS

Figure 15-2 Iu Flex configuration model

15.4.2 Pool Area

In one pool area, a UE roams without need to change the serving CN node. One pool

area is served by one or more CN nodes in parallel.

The complete serving area of a RAN node belongs to one or more pool areas when

multiple overlapping pool areas include this RAN node serving area.

I. Characteristics

The pool area has the following characteristics:

A pool area is a collection of one or more MSC or SGSN serving areas.

A pool area is served by one or more CN nodes in parallel that share the traffic

of this area between each other.

The pool areas may overlap. The RAN node belongs to all the overlapping pool

areas.

In one pool area, the UE roams without need to change the serving CN node.

The pool areas of the CS domain and of the PS domain are configured

independently.

II. Implementation

Within a pool area, a UE is served by a specific CN node, as shown in Figure 15-3.


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Area 1

RANnode

Area 5

RANnode

Area 6

RANnode

Area 7

RANnode

Area 8

RANnode

Area 2

RANnode

Area 3

RANnode

Area 4

RANnode

PS pool-area 2PS pool-area 1

CS pool-area 2CS pool-area 1

MSC 3MSC 2

MSC 1

MSC 6MSC 5

MSC 4

SGSN 6

SGSN 2

SGSN 1

SGSN 5SGSN 4

SGSN 3

MSC 7

Figure 15-3 Pool area configuration example

There are four pool areas in this figure: CS pool area 1, CS pool area 2, PS pool area

1 and PS pool area 2. The pool areas are described as follows:

CS pool area 1: including RAN serving areas 1, 2, 5, and 6 served by MSCs 1, 2,

and 3

CS pool area 2: including RAN serving areas 2, 3, 6, and 7 served by MSCs 4, 5,

and 6

PS pool area 1: including RAN serving areas 1 and 5 served by SGSNs 1 and 2

PS pool area 2: including RAN serving areas 2, 3, 6, and 7 served by SGSNs 3,

4, and 5

RAN serving areas 4 and 8 are served by MSC 7 and SGSN 6 without using the

Iu Flex.

CS pool areas 1 and 2 overlap.

PS pool areas 1 and 2 do not overlap.

The pool areas of the CS and the PS domain may be configured identical as shown

by CS pool area 2 and PS pool area 2, or differently as shown by CS pool area 1 and

PS pool area 1.

The number and capacity of CN nodes are configured independently for each pool

area.

The Iu Flex can be configured only in parts of the network. The Iu-Flex-capable pool

areas co-exist with the areas that are not using this feature, for example, the RAN

node areas 4 and 8 served by MSC 7 and SGSN 6 as shown in Figure 15-3.


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15.4.3 NRI

The Network Resource Identity (NRI) identifies uniquely an individual CN node that

serves a pool area. Each CN node that supports the Iu Flex is configured with one or

more specific NRIs.

I. Characteristics

The NRI has following characteristics:

In a pool area, the NRI identifies uniquely a CN node.

The NRI is part of the Temporary Mobile Station Identity (TMSI) for the CS

domain or Packet TMSI (P-TMSI) for the PS domain. It is assigned by the

serving CN node to the UE. The TMSI or P-TMSI allocation mechanism in the

CN node generates TMSIs or P-TMSIs that contain a configured NRI in the

relevant bit positions.

The length of the NRI in bits ranges from 0 to 10 bits. The value 0 means that no

NRI is in use. The lengths of the NRIs are the same in all nodes of a domain in

one pool area.

In case of overlapping pool areas, the NRI lengths shall be configured the same

in all the nodes of a specific domain serving these pool areas.

The NRIs of the CS and the PS domain are independent of each other as the CN

nodes of the PS and the CS domain are accessed independently.

The corresponding relationship between the NRI and the CN nodes in the CN

pool area is configured in the RAN nodes. In CN pool areas, each CN node is

configured with the NRIs of other CN nodes.

II. Implementation

In the WCDMA system, the UE sends an RRC INITIAL DIRECT TRANSFER

message to the RAN node that contains an IE ”Intra Domain NAS Node Selection

(IDNNS)”. The IDNNS contains a route parameter with a fixed length of 10 bits that

transports the NRI value. In addition, the IDNNS contains an indication about from

which identity (TMSI/PTMSI, IMSI, IMEI) the route parameter is derived. The RAN

node masks the significant bits out of the route parameter part of the IDNNS to

determine the NRI that is relevant to identify the CN node.

15.4.4 NNSF

The NAS Node Selection Function (NNSF) selects the proper CN node (MSC or

SGSN) for the UE and sets up the traffic link to the selected CN node.

If the NNSF finds the CN node that the NRI derived from the initial NAS signaling

message identifies, it routes the message or frame to that CN node. Otherwise, the

NNSF selects an available CN node according to the signaling load balancing and

routes the message to the selected CN node.


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I. Characteristics

In the RAN node, the NNSF selects the specific CN node (MSC or SGSN) and routes

the initial NAS signaling messages to the selected node.

II. Implementation

The process is as follows:

2) The CN node allocates the route information to the UE. If the CN node supports

the Iu Flex, the TMSI (or P-TMSI) allocated by the node contains the NRI.

3) The UE encodes the route information according to the TMSI (or P-TMSI), IMSI

or IMEI to get the route parameter. The parameter consists of 10 bits. Then the

UE sends the parameter to the RNC through the INITIAL DIRECT TRANSFER

message.

4) The RNC selects the route according to the route parameter derived from the

INITIAL DIRECT TRANSFER message.

The details of the process are described as follows:

1) The CN node informs the UE of the route information.

When the CN node allocates the TMSI or P-TMSI to the UE, the node includes

its NRI in the bits 14–23. The length of the NRI ranges from 0 to 10 and needs to

be configured at the CN node and the RNC.

If the length is set to 0, it is an indication that no NRI is in use, that is, the Iu

Flex is not used.

If the length is set to n, it is an indication that the n bits from bit 14 are the

NRI.

2) The UE encodes the route information based on the sources that the route

information is derived from. The following sources are available:

TMSI or P-TMSI

The route parameter is obtained by the encoding of bits 14–23 in the

information elements (IE) identified by the TMSI or P-TMSI.

IMSI

The parameter value is (IMSI / 10) MOD 1000. It is an integer within the

range from 0 through 999. For route selection, each integer is configured to

a CN node on the RNC LMT.

IMEI

The parameter value is (IMEI / 10) MOD1000. It is an integer within the

range from 0 through 999. For route selection, each integer is configured to

a CN node on the RNC LMT.

The UE encodes the route information according to the following rules:


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The UE preferentially encodes the route information identified by the TMSI

or P-TMSI.

If the TMSI or P-TMSI is unavailable and the UE contains the USIM or SIM

card, the UE encodes the route information identified by the IMSI.

If the TMSI or P-TMSI is unavailable and the UE does not contain the USIM

or SIM card, the UE encodes the route information identified by the IMEI.

The length of the route parameter after encoding is 10 bits. The parameter and

the encoding mode are saved in the IDNNS of the INITIAL DIRECT TRANSFER

message, which is sent to the RNC.

3) The RNC selects the route based on the route parameter in the IDNNS of the

INITIAL DIRECT TRANSFER message as follows:

When the route parameter is derived from the TMSI or P-TMSI

The RNC derives the NRI from the parameter according to the configured

length of the NRI. Then the RNC selects the CN node according to the

configured corresponding relationship between the NRI and the CN node. If

no NRI is configured to the CN node, the RNC selects a CN node based on

the load balancing.

The length of the NRI is configured for the CN domains as Length of CS

NRI in bits and Length of PS NRI in bits respectively.

Parameters:

Parameter Name Length of PS NRI in bits

Parameter ID PSNRILength

GUI Range 1–10

Physical Range& Unit None

Default Value Value according to the data from CN configuration

Optional/Mandatory Optional

MML Command SET IUFLEX

Description:

If the specified CN domain is set as supporting the Iu Flex function, Length of the

NRI in bits must be set.


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Parameter Name Length of CS NRI in bits

Parameter ID CSNRILength

GUI Range 1–10



Optional/Mandatory Optional

MML Command SET IUFLEX

Description:

If the specified CN domain is set as supporting the Iu Flex function, Length of the

NRI in bits must be set.

Parameter Name Network resource identity

Parameter ID NRI

GUI Range 0–1023



Optional/Mandatory Mandatory

MML Command ADD NRIGLBCNIDMAP

MOD NRIGLBCNIDMAP

Description:

One CN node may have many different NRIs.

Different CN nodes connected to the same RNC must use different NRIs.

For example, CS CN node 1 has an NRI of 5, and the Length of CS NRI in

bits is set to 6. If the route parameter derived from the TMSI IDNNS in an

INITIAL DIRECT TRANSFER message is 000101**** (totally 10 bits; * can be

‘0’ or ‘1’ ), then this message will be routed to CN node 1.

When the route parameter is derived from the IMSI

The parameter is an integer within the range from 0 through 999. The value

can be derived by (IMSI/10) MOD 1000. The RNC selects the CN node

according to the configured corresponding relationship between the IMSI


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IDNNS route parameter and the CN node. One integer is configured to one

specific CN node.

The RNC configures the relationship between the IMSI IDNNS route

parameter and a CN node as that the CN node has a range from Minimum

of IMSI route parameter in IDNNS to Maximum of IMSI route parameter

in IDNNS. If the IMSI IDNNS route parameter is in this range, the RNC will

route the UE to the specified CN node.

Parameters:

Parameter Name Minimum of IMSI route parameter in IDNNS

Parameter ID ImsiRtMin

GUI Range 0–999


Default Value None


MML Command ADD IMSIIDNNSCNIDMAP

MOD IMSIIDNNSCNIDMAP

Description:

The relationship between the IMSI IDNNS route parameter’s value range and the

CN node allows a group of UEs to be routed to one CN node.

In this case, the operator can plan the ranges between CN nodes according to

their capability. If one CN node can afford more UEs, a larger range can be

assigned to it.

It is recommended not to overlay the range for different CN nodes in the same CN

domain.


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Parameter Name Maximum of IMSI route parameter in IDNNS

Parameter ID ImsiRtMax

GUI Range 0–999


Default Value None


MML Command ADD IMSIIDNNSCNIDMAP

MOD IMSIIDNNSCNIDMAP

Description:

The relationship between the IMSI IDNNS route parameter’s value range and the

CN node allows a group of UEs to be routed to one CN node.

In this case, the operator can plan the ranges between CN nodes according to

their capability. If one CN node can afford more UEs, a larger range can be

assigned to it.

It is recommended not to overlay the range for different CN nodes in the same CN

domain.

When the route parameter is derived from the IMEI

The RNC selects the CN node based on load balancing.

III. Processing the IMSI Paging Message by the NNSF (CS domain)

To increase the success rate of routing the paging response message to the CN node

that issues the paging request, the Iu-Flex-capable RNC needs to process the IMSI

paging message as follows:

In R5 protocols, an optional IE “Global CN-ID” is added to the RANAP PAGING

message. If RNC provides the Iu Flex feature and the paging message contains

only the IMSI rather than the TMSI, the paging message must contain Global

CN-ID.

The NNSF in the RNC temporarily stores the IMSI and Global CN-ID upon

reception of the paging message. When the NNSF receives the INITIAL DIRECT

TRANSFER message (a paging response with an IMSI), it directly forwards the

paging response to the CN node identified by the Global CN-ID.

If the CN node is set to Mode 1, that is, the Gs interface exists, the paging

message of the CS domain might be delivered on the Iu-PS interface. In this


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case, the SGSN adds the Global CN-ID of the CS domain into the paging

message.

IV. Processing the IMSI Paging Message by the NNSF (PS domain)

The RNC does not need to save the Global CN-ID when the RNC processes the IMSI

paging message for the PS domain.

According to 3GPP TS 23.236, a UE returns an Attach Request containing the IMSI

parameter as a response to the IMSI paging that it receives from the PS domain.

Moreover, the SGSN does not start the timer for the PS IMSI paging after sending the

message. Therefore, the NNSF in the RAN node does not need to save the SGSN ID

when it receives the paging request.

15.4.5 Load Balancing and Flow Control

The NNSF balances the signaling load between the available CN nodes. This is

performed by selecting a proper CN node for the UE that has not been assigned to a

CN node, for example, when there is no CN node configured for the NRI indicated by

the UE or when the CN node corresponding to an NRI cannot be reached.

The process is described as follows:

1) When the CN node is overloaded, the CN sends an overload message to the

RNC to initiate the flow control procedure.

2) The RNC activates the CN short-time flow control timer IGORTIMR and the CN

long-time flow control timer INTRTMR, and then it discards INITIAL DIRECT

TRANSFER messages from the UE at the proportion of the step specified in the

overload message multiplied by 5.

If the RNC receives the overload message only once and the step specified

in the message is 2, 10% INITIAL DIRECT TRANSFER messages will be

discarded, because 2 x 5% = 10%.

If the RNC receives overload messages continually, the traffic is reduced all

the way until it reaches the lower limit of 30%.

The functions of the two types of flow control timers are described as follows:

The CN short-time flow control timer IGORTMR is used to prevent the CN

from sending overload messages continually.

Continual transmission of overload messages is invalid before this timer

expires.

The CN long-time flow control timer INTRTMR is used to control the

recovery of the traffic flow.

The traffic flow is recovered at the rate of 1 x 5%, that is, each time the timer

expires, the traffic volume increases 5%.


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15.4.6 Support of the RNC on the Iu Flex

The RNC implements the Iu Flex as follows:

3) The RNC gets the NRI from the IDNNS in the INITIAL DIRECT TRANSFER

message. Then it finds the CN node according to the corresponding relationship

between the NRI and the CN node that is configured in the RNC LMT.

4) The RNC saves the relationship between IMSI and Global CN-ID if the paging

massage that the RNC receives from the CS domain does not carry the TMSI.

After receiving from the UE the INITIAL DIRECT TRANSFER massage that is

the response to the paging, the RNC routes the UE to the correct CN domain

according to the relationship.

5) The RNC selects a CN node from the available CN nodes according to the load

balancing under any of the following situations:

The selected CN node is not available.

No CN node is configured for the requested NRI.

The provided identity contains no NRI.

6) The RNC routes the signaling connection message to the selected CN node.

15.4.7 Impact on Signaling Procedures

The Iu Flex has impact on the following signaling procedures:

Traffic request for starting Attach and the UE

Traffic starting request on network side (IMSI paging)

Update of the routing area

IMSI attach process/ location update with IMSI

In these procedures, the UE provides the IDNNS to the RNC by sending an

RRC_initial_DT message. The RNC selects the route according to the route

parameters in the INITIAL DIRECT TRANSFER message, gets the destination CN

node address and sends the INITIAL UE message to the CN node.

15.5 Capabilities

None.

15.6 Implementation

15.6.1 Enabling Iu Flex

I. Hardware Installation

The Iu Flex module is integrated into the RNC and CN node. No extra hardware is

required.


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II. License Update

Purchase the related license, and then perform the following steps:

7) Get the new license.

8) Download the license to BAM software installation directory\FTP\license through

File Transfer Protocol (FTP).

9) Execute ACT LICENSE on the M2000 or RNC Local Maintenance Terminal

(LMT) to activate the license.

III. Data Configuration

To configure the data, perform the following steps:

10) Execute ADD CNDOMAIN to add the CN domain data.

11) Execute ADD CNNODE to add the CN node data. Set CN protocol version to

R5 or a higher value.

12) Execute SET IUFLEX to set the Iu Flex feature and the parameters CS NRI

length and PS NRI length.

13) Execute ADD NRIGLBCNIDMAP to add the mapping between the NRI and the

Global CN-ID.

14) Execute ADD IMSIIDNNSCNIDMAP to add the mapping between the IMSI route

parameters and the Global CN-ID.

For details about parameter configuration on the CN side, refer to the related

documentation.

IV. Verification of the Enabled Feature

To verify the enabled feature, execute LST IUFLEX on the RNC LMT to check the Iu

Flex configuration at the RNC for both CN domains.

V. Example

Assume that the pool area contains two MSCs: MSC 1 and MSC 2. The ID of the

local RNC is 1. Table 15-1 lists the data negotiated for the Iu Flex.

Table 15-1 Data negotiated for the Iu Flex

Item MSC 1 MSC 2

NRI length 4 4

NRI 8 9

CN node ID 1 2

CN node MCC 460 460


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Item MSC 1 MSC 2

CN node MNC 08 08

Value range of the IMSI route parameter

in the IDNNS0–300, 800–900 301–799, 901–999

//(1) Update the license.

//(2) Add the CN domain data.

ADD CNDOMAIN: CNDomainId=CS_DOMAIN;

ADD CNDOMAIN: CNDomainId=PS_DOMAIN;

//(3) Add the CN node data.

ADD CNNODE: CNId=1, CNDomainId=CS_DOMAIN, Dpx=1, CNProtclVer=R5,

SupportCRType=CR529_SUPPORT;

ADD CNNODE: CNId=2, CNDomainId=CS_DOMAIN, Dpx=2, CNProtclVer=R5,

SupportCRType=CR529_SUPPORT;

//(4) Set the Iu Flex feature.

SET IUFLEX: CsIuFlexFlag=ON, NNSfTmr=3, CSNRILength=4;

//(5) Add the mapping between the NRI and the Global CN-ID.

ADD NRIGLBCNIDMAP: CNId=1, NRI=8;

ADD NRIGLBCNIDMAP: CNId=2, NRI=9;

//(6) Add the mapping between IMSI route parameters and the Global CN-ID.

ADD IMSIIDNNSCNIDMAP: CNNodeMCC="460", CNNodeMNC="08", ImsiRtMin=0,

ImsiRtMax=300, CNId=1;







15.6.2 Reconfiguring Iu Flex Parameters

To reconfigure Iu Flex parameters, perform the following steps:

15) Execute LST CNDOMAIN to query the CN domain data, and then execute MOD

CNDOMAIN to modify the data as required.


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16) Execute LST CNNODE to query the CN node data, and then execute MOD

CNNODE to modify the data as required.

17) Execute LST IUFLEX to query the Iu Flex configuration, and then execute SET

IUFLEX to modify the configuration as required.

18) Execute LST NRIGLBCNIDMAP to query the mapping between the NRI and the

Global CN-ID, and then execute RMV NRIGLBCNIDMAP or ADD

NRIGLBCNIDMAP to remove or add the mapping as required.

19) Execute LST IMSIIDNNSCNIDMAP to query the mapping between IMSI route

parameters and the Global CN-ID, and then execute RMV

IMSIIDNNSCNIDMAP or ADD IMSIIDNNSCNIDMAP to remove or add the

mapping as required.

15.6.3 Disabling Iu Flex

I. Data Configuration

To disable the Iu Flex feature on the RNC side, perform the following steps:

20) Execute RMV IMSIIDNNSCNIDMAP to remove the mapping between IMSI route


21) Execute RMV NRIGLBCNIDMAP to remove the mapping between the NRI and

the Global CN-ID.

22) Execute SET IUFLEX to set the CS and PS domains to not supporting the Iu

Flex.

II. Verification of the Disabled Feature

To verify that the Iu Flex feature is disabled, execute LST IUFLEX on the RNC LMT.

III. Example

//(1) Remove the mapping between IMSI route parameters and the Global CN-ID.

RMV IMSIIDNNSCNIDMAP: CNNodeMCC="460", CNNodeMNC="08", ImsiRtMin=0,








//(2) Remove the mapping between the NRI and the Global CN-ID.


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RMV NRIGLBCNIDMAP: NRI=8, CNId=1;

RMV NRIGLBCNIDMAP: NRI=9, CNId=2;

//(3) Set the CS and PS domains to not supporting the Iu Flex.

SET IUFLEX: CsIuFlexFlag=OFF, PsIuFlexFlag=OFF;

15.7 Maintenance Information

15.7.1 MML Commands Related to Iu Flex

Command Executed to…

ADD CNDOMAIN Add the CN domain data.

MOD CNDOMAIN Modify the CN domain data.

ADD CNNODE Add the CN node data.

MOD CNNODE Modify the CN node data.

LST IUFLEX List the Iu Flex configuration.

SET IUFLEX Set the Iu Flex data.

ADD NRIGLBCNIDMAPAdd the mapping between the NRI and the Global

CN-ID.

RMV NRIGLBCNIDMAPRemove the mapping between the NRI and the

Global CN-ID.

ADD IMSIIDNNSCNIDMAPAdd the mapping between IMSI route parameters

and the Global CN-ID.

RMV IMSIIDNNSCNIDMAPRemove the mapping between IMSI route


15.7.2 Alarms

None.

15.7.3 Counters

None.


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15.8 References

3GPP TS 23.236 5.2.0 "Intra-domain connection of Radio Access Network

(RAN) nodes to multiple Core Network (CN) nodes"

3GPP TS 25.875 5.0.0 "Non Access Stratum (NAS) Node Selection Function"

3GPP TS 25.401 5.2.0 "UTRAN Overall Description"

3GPP TS 25.410 5.0.0 "UTRAN Iu Interface: General Aspects and Principles"

3GPP TS 25.413 5.0.0 "UTRAN Iu interface RANAP signalling"

3GPP TS 25.331 "Radio Resource Control (RRC)”


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Documents

15-Iu Flex