Flexi Direct System Description

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WCDMA RAN, Rel. RU30,

Operating Documentation,

Issue 12

Flexi Direct System Description

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The information in this document is subject to change without notice and describes only the

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Table of contentsThis document has 74 pages.

Summary of changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

1 Introduction to Nokia Siemens Networks Flexi Direct System. . . . . . . . 11

2 Network architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

2.1 Flexi Direct architecture. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

2.2 Network elements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

2.3 Network deployment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

2.3.1 Greenfield scenario . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

2.3.2 2G/3G network overlay scenario . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

2.3.3 Flexi Direct external interfaces. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

2.4 Capacity and efficiency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

2.4.1 DC-HSDPA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

2.4.2 Flexible RLC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

2.4.3 Flexible Iu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

2.4.4 HSPA 72 Users Per Cell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

2.4.5 Common Channel Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

2.4.6 Multi-Operator Radio Access Network. . . . . . . . . . . . . . . . . . . . . . . . . . 23

2.4.7 Multi-Operator Core Network. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

3 Mobility. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

3.1 Mobility management. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

3.1.1 Intra-system handover with Iur. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

3.1.2 Intra-system handover without Iur . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

3.1.3 Soft Handover Based on Detected Set Reporting . . . . . . . . . . . . . . . . . 25

3.1.4 Inter-frequency handover over Iur . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

3.1.5 Inter-system handover between the Flexi Direct and WCDMA RAN. . . 26

3.1.6 Mobility between Flexi Direct and 2G network. . . . . . . . . . . . . . . . . . . . 26

3.1.7 Mobility between Flexi Direct and LTE. . . . . . . . . . . . . . . . . . . . . . . . . . 27

3.1.8 HSPA Capability Based Handover. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

3.1.9 Load and service based IS/IF handover . . . . . . . . . . . . . . . . . . . . . . . . 27

3.1.10 IMSI-based handover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

3.1.11 Inter-frequency handover. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

3.1.12 HSPA over Iur in Flexi Direct BTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

4 Voice Service support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

4.1 CS AMR Voice support in Flexi Direct BTS . . . . . . . . . . . . . . . . . . . . . . 29

4.2 VoIP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

4.3 HSDPA/HSUPA with simultaneous AMR support . . . . . . . . . . . . . . . . . 29

5 Location services (LCS). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

6 Paging in Flexi Direct Network. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

6.1 Paging Optimization in Flexi Direct Network . . . . . . . . . . . . . . . . . . . . . 33

6.2 Paging Channel with data rate of 24 Kbps . . . . . . . . . . . . . . . . . . . . . . 34

7 Radio resource management in Flexi Direct . . . . . . . . . . . . . . . . . . . . . 35

7.1 MIMO feature. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35



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7.2 Fast Dormancy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

7.3 HSUPA interference cancellation receiver . . . . . . . . . . . . . . . . . . . . . . . 36

7.4 Frequency Domain Equalizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

7.5 Extension of RNC identification numbers . . . . . . . . . . . . . . . . . . . . . . . . 36

8 Transport. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

8.1 Flexi Direct transport. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

8.1.1 Transport interfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

8.1.2 Flexi Transport Sub-Modules (FTM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

8.1.3 Control plane protocols. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

8.1.4 User plane protocols. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

8.1.4.1 Iu-CS higher level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

8.1.4.2 Iu-PS higher level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

8.1.4.3 Iur higher level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

8.1.4.4 Iu-PC and O&M interfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

8.1.4.5 Iu-BC interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

8.1.5 IP over ATM transport option . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

8.1.5.1 ATM Adaptation Layer 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

8.1.5.2 ATM Layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

8.1.6 Basic Ethernet Switching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

8.1.7 Synchronization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

8.1.8 IP Security. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

8.1.9 Hybrid Transport solutions for Flexi Direct BTS . . . . . . . . . . . . . . . . . . . 47

8.2 QoS support on IP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

9 Security. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

9.1 Security foundations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

9.1.1 Security features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

9.2 User security. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

9.2.1 Authentication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

9.2.2 Authorization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

9.2.3 User event logging and log collection. . . . . . . . . . . . . . . . . . . . . . . . . . . 54

10 Operability overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

10.1 Introduction to Flexi Direct System operability . . . . . . . . . . . . . . . . . . . . 55

10.2 Flexi Dirext System operability architecture . . . . . . . . . . . . . . . . . . . . . . 56

10.3 Flexi Direct OMS Element Manager . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

10.4 Autoconnection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

10.5 Remote Commissioning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

10.6 Configuration management. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

10.6.1 Topology management in Flexi Direct System . . . . . . . . . . . . . . . . . . . . 63

10.6.2 Plan management in Flexi Direct System . . . . . . . . . . . . . . . . . . . . . . . . 64

10.7 Performance management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

10.7.1 Performance management in Flexi Direct System . . . . . . . . . . . . . . . . . 67

10.8 Fault management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

10.8.1 Fault Management Architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

10.8.2 Fault management in Flexi Direct System . . . . . . . . . . . . . . . . . . . . . . . 70

10.9 Software management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

10.9.1 Software management in Flexi Direct System . . . . . . . . . . . . . . . . . . . . 72



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10.10 User management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74



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List of figuresFigure 1 Flexi Direct System architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Figure 2 Flexi Direct architecture for greenfield case with no CS support . . . . . . 15

Figure 3 Flexi Direct architecture evolution to LTE; Direct Tunnel . . . . . . . . . . . . 16

Figure 4 Nokia Siemens Networks Flexi Direct OMS . . . . . . . . . . . . . . . . . . . . . . 18

Figure 5 Pure Flexi Direct Network . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Figure 6 Flexi Direct as data overlay network . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Figure 7 Flexi Direct mobility - Gn based . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Figure 8 Location services for Flexi Direct . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Figure 9 Paging Optimization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

Figure 10 Iu-CS, Iu-PS and Iur Control Plane. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Figure 11 Iu-CS User Plane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

Figure 12 Iu-PS User Plane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

Figure 13 Iur User Plane. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41Figure 14 Iu-PC interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Figure 15 O&M interfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

Figure 16 Protocol architecture for the Service Area Broadcast with IP over Ethernet.

42

Figure 17 ToP Architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

Figure 18 Protocol stack for ToP. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

Figure 19 Logical IP Sec Architecture. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Figure 20 Flexi Direct System operability architecture . . . . . . . . . . . . . . . . . . . . . . 57

Figure 21 Flexi Direct OMS Element Manager architecture . . . . . . . . . . . . . . . . . . 59

Figure 22 Flexi Multiradio BTS reconfiguration to Flexi Direct-BTS functionality . . 61

Figure 23 Flexi Direct topology tree view screen capture . . . . . . . . . . . . . . . . . . . . 64Figure 24 Fault management functionality architecture in Flexi Direct System . . . 70



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List of tablesTable 1 Flexi Direct transport scenarios overview . . . . . . . . . . . . . . . . . . . . . . . 47

Table 2 DSCP mapping - default values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

Table 3 VLAN priority bits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49



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Flexi Direct System Description Summary of changes

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Summary of changes

Changes between issues 04E (2012-08-17, RU30) and 04F (2012-10-19, RU30)

Rebranding from I-HSPA to Flexi Direct.

2G/3G network overlay scenario (2.3.2)

• Updated the explanation with:

“In the second scenario, Flexi Direct data overlay network is built on top of the

existing networks.

In this case Flexi Direct works on its own radio carrier frequency or in the same fre-

quency as existing 3G network to enhance coverage and capacity.

Both CS and PS services are all supported by the Flexi Direct network. Mobility with

existing RNC-based 3G network is handled either as soft handover or hard han-

dover. Flexi Direct BTS supports 3GPP standard Iur interface towards the RNC and

thus inter-RNC soft handover and relocations between the Flexi Direct BTS andRNC are possible.”

HSDPA/HSUPA with simultaneous AMR support (4.3)

• Updated the explanation with:

“The UE does not need to be transitioned to the DCH transport channel for the

ongoing HSDPA/HSUPA bearers when the CS voice call is initiated. This ensures

that an AMR voice call initiation does not influence the HSDPA/HSUPA service data

flow.

Location services (5)

• Removed: “Broadcast of A-GPS Assistance Data enables the broadcasting of the

Assistance data of A-GPS positioning method via the SIB 15. When this feature is

enabled, the dedicated signaling towards the UE is avoided.”

Topology management in Flexi Direct System (10.6.1)

• Added an information: “Note that OMS is labeling the Flexi Direct topology as in the

GUI as “I-HSPA topology”.

Changes between issues 04D (2012-03-16, RU30) and 04E (2012-08-17, RU30)

Network elements (2.2)

• Number of Flexi Direct BTSs supported by OMS updated to 1200.

Voice Service support (4)

• Removed section 4.2 CS Service Enabling HO

Flexi Direct System operability architecture (10.2)

• Figure: Flexi Direct System Operability updated to explicitly show that BTSOM inter-

face is mediated to BTS through Flexi Direct BTS internal Iub interface.

• Removed XML label in Figure: Flexi Direct System operability architecture

• Added “Even if NetAct is used for centralized management, OMS must be present

as an O&M mediator and aggregator.



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Summary of changes

Flexi Direct OMS Element Manager (10.3)

• Changed the direction of arrows in Figure: Flexi Direct OMS Element Manager archi-

tecture.

Plan management in Flexi Direct System (10.6.2)

• Removed CM Editor screenshot.

Changes between issues 04B (2011-09-23, RU30) and 04C (2011-11-25, RU30)

Flexi Direct transport (8.1)

• FTM information updated. Only FTLB transport submodule is supported.



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1 Introduction to Nokia Siemens Networks

Flexi Direct System

Flexi Direct System is a cost efficient solution for packet switched (PS) and circuitswitched (CS) networks. The biggest advantage of Flexi Direct is a flat architecture of

the Radio Access Network (RAN). The WCDMA operator gains from a high capacity and

low cost RAN solution, which resolves the bottleneck for the growth of HSPA traffic. No

changes are required in the existing Core Network (CN) elements.

The flat architecture enables low latency, high capacity and low cost for PS traffic ser-

vices. It is implemented by relocating the Radio Network Controller (RNC) functionality

into the Flexi Direct RNC which is a part of Flexi Multiradio BTS. In Flexi Direct Rel4.0

the Flexi Direct RNC is a logical entity from the architecture point of view and it is a part

of the transport module of Flexi Multiradio BTS. This means that there is no separate

hardware needed to support Flexi Direct. During the commissioning procedure the Flexi

Multiradio BTS with FTLB transport module is converted into an Flexi Direct BTS withFlexi Direct RNC functionality. This is performed through both remote and on site com-

missioning with software upgrade. After Flexi Multiradio BTS software upgrade the Flexi

Direct functionality is available. Though the Flexi Direct RNC functionality is realized as

part of Flexi Multiradio BTS Transport Hardware, Flexi Direct RNC will still remain a

separate logical entity.

The Flexi Direct RNC takes over the RNC functionality with respect to PS and CS

services. Flexi Direct RNC main functionalities are listed below:

• protocol termination and handling for the following interfaces:

• Iu-CS and Iu-PS control plane (RANAP)

• Iu-CS and Iu-PS user plane (GTP-u/Gn-u, Iu-U)

• Iur interface protocol stacks

• Radio Resource Management

• Security Management

• Mobility

Flexi Direct uses Serving GPRS Support Node (SGSN) and Gateway GPRS Support

Node (GGSN) network elements to handle mobility in the PS domain. The use of SGSN

and GGSN network elements allows the same IP point of attachment for traditional

WCDMA and HSPA networks. In the CS domain the Flexi Direct uses Media Gateway

(MGW) for user plane and the MSC server (MSS) for control plane signaling. Flexi Direct

supports CS AMR voice services with mobility functionality that is identical towards

WCDMA and Flexi Direct network.Flexi Direct fulfills the following generic features:

• network architecture that is optimized for the PS traffic

• support for the standard compliant terminals

• optimized radio interface for the Flexi Direct

• optimized user plane and round trip time (RTT) for the PS

• optimized control plane and connection set-up time

• optimized transmission interface for the PS traffic

• flexible RLC, PDU overhead reduced

• multi-operator Core Network

• direct resource allocation for HSPA transport channels during RAB establishment



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Introduction to Nokia Siemens Networks Flexi DirectSystem

Flexi Direct uses a Direct tunnel solution that allows bypassing of the SGSN in the user

plane for PS data. This solution enables the operator to use the existing packet switched

network (PS) with optional direct tunnel optimization.

Flexi Direct flat radio access architecture offers operators the following Long Term Evo-lution (LTE)/System Architecture Evolution (SAE) benefits:

• cost benefits with fewer user plane elements

• cost benefits as existing SGSNs with the Direct tunnel support can be used

• performance benefits with fewer elements (lower setup delay and lower user plane

latency)

• possibility to utilize cheaper transport solutions (for example, Ethernet based

transport with external Sync)



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2 Network architecture

2.1 Flexi Direct architectureFlexi Direct System is designed and optimized for packet data transmission and can be

deployed as a data overlay network on top of an existing network architecture. It is also

possible to deploy Flexi Direct in a greenfield scenario, in case there is no existing

network available. Both PS and CS services can be provided with Flexi Direct.

Flexi Direct System comprises of traditional WCDMA network elements. Flexi Direct can

use the same MSS, MGW, SGSN and GGSN network elements with the traditional

WCDMA and HSPA networks. The Flexi Direct BTS network element is connected to

the 3GPP Core Network (CN) via the 3GPP standard Iu-PS/Gn and Iu-CS interfaces.

Figures Flexi Direct System architecture, Flexi Direct Architecture for the greenfield and

Flexi Direct architecture evolution to LTE describe the architecture solutions for Flexi

Direct System.



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Network architecture

Figure 1 Flexi Direct System architecture

g Flexi Direct BTS consists of two NE elementary types, WCDMA BTS and Flexi Direct

RNC. On O&M level they are visible as a separate NE types. WCDMA BTS is located

under Flexi Direct RNC in the structure.

In the Flexi Direct network architecture, the role of Iur is as follows:

• the interface betweenFlexi Direct BTSs, RNSAP is used.

• the interface between Flexi Direct BTS and a 3G RNC, 3GPP compliant RNSAP is

used on this interface.

In Flexi Direct, that is enhanced by Direct Tunnel solution, the user plane traffic is sent

directly towards GGSN. SGSN is transparent, the user plane is carried over the Gn-uinterface between the Flexi Direct BTS and the GGSN. This solution has an impact on

Iur

IuBC

IuPS-C

Iub

Iur Iur

IuCS-U

Gn-U

Gn-C

GTPBTSOM

NWI3

GGSN

SGSN

MGW

MSS

CBC

RNC

Go

Gi

CG

SAS

SASNetActOMS

WCDMA BTS

Flexi Direct BTS

Flexi Direct BTS

Content andConnectivity

Internet + Intranet

IMS: IM, Presence,PoC, Video Sharing

IuCS-C

IuCS-C

IuPC

IuPC

BTSOM

Iupc

WCDMA BTS

Iub



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SGSN, it has to support Direct Tunnel. The SGSN coordinates the direct tunnel estab-

lishment between the Flexi Direct BTS and the GGSN. Although it is an optional solution,

it is recommended to use Direct Tunnel for the low delay and high capacity networks,

such as Flexi Direct. NSN Core supports Direct Tunnel Solution. Flexi Direct also

supports the Iu-PS user plane (for example without Direct Tunnel solution) transmission

towards the SGSN.

Flexi Direct network makes maximum reuse of existing back-office infrastructure for

services, subscriber management, and accounting. Iu/Gn based model enables fast and

cost efficient integration towards the operators’ existing WCDMA network. Flexi Direct

also supports a complete greenfield implementation. In this case the surrounding

infrastructure is built from the scratch. In some greenfield cases, the CS support is

omitted.

Figure 2 Flexi Direct architecture for greenfield case with no CS support

Flexi Direct is defined to be a pre-step for LTE (3GPP SAE/LTE). It uses LTE architec-

ture, the radio interface is based on HSPA.

Content &Connectivity

Internet +Intranets

IMS:IM, Presence, PoC

Video sharingVoIP, IP Centrex

SGSN GGSN

Flexi Direct BTS

Flexi Direct BTS

HSPA UE

HSPAdevice

Standardized

Standardized withvendor specific extensions

Flexi DirectIntra-system

handover



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Network architecture

Figure 3 Flexi Direct architecture evolution to LTE; Direct Tunnel

The main benefits of Flexi Direct flat network architecture:

• Cost benefits

Upgrade cost of traditional WCDMA RAN with centralized RNC is very high

compared to the flat architecture. This will be more evident with the ever growing

HSPA traffic in the 3G network. • Performance improvement

Flat network architecture with Direct Tunnel solution reduces the number of network

elements chained, thus round trip time is improved.

IP Transport reduces overhead, thus improving the transport capacity.

WCDMA BTSFlexi Direct BTS

RNC

SGSNMME

GatewayServing PDN

S4S7

S3SGi

S1-U

S1-MME

S11

Rx+

S2c S6a S6bHSS

User planeControl plane

PCRF

Iu

IubUtran

Flexi Direct

LTE

Operator ServicesInternet

CorporateServices

GatewayS5



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2.2 Network elements

The Flexi Direct System network elements are the following:

• Flexi Direct BTS (WCDMA BTS plus Flexi Direct RNC)

• MSC server

• MGW

• SGSN

• GGSN

• OMS

• User Equipment (UE)

• NetAct

Flexi Multiradio BTS for Flexi Direct (Flexi Direct BTS)

The Flexi Direct BTS consists of a Flexi Multiradio BTS for WCDMA and Flexi Direct

RNC. The Flexi Direct RNC is integrated into the FTLB transport module. On O&M levelFlexi Direct RNC and WCDMA BTS are handled as individual objects.

Flexi Direct radio network layer uses all the Flexi Direct BTS resources, all the radio

carriers and associated logical cells supported by that particular configuration.

Flexi Direct RNC is a network element responsible for managing HSPA traffic in an Flexi

Direct network. From the network perspective, it allows moving PS and CS functionality

from a classical RNC to the Flexi Multiradio BTS site.

When the Flexi Multiradio BTS for WCDMA is commissioned to the Flexi Direct BTS, the

Iub interface becomes internal. Therefore, no external Iub is needed.

MSS

Flexi Direct supports standard MSC server, both the 3GPP compliant Iu-CS control anduser plane are supported. IP-based Iu-CS interface is supported.

MGW

Nokia Siemens Networks Multimedia Gateway (MGW) is used for transmitting and con-

verting the user plane traffic in both circuit-switched core networks and IP Multimedia

Subsystem. It is also a border element between different kinds of networks, the PSTN

and the PLMN, the IMS and the CS core network. The MGW consists of several func-

tional elements configured under the gateway architecture. A number of different con-

figurations of the MGW can be used depending on the services required by the operator.

SGSN

Flexi Direct System uses the standard SGSN interfaces. The operator can use the

existing SGSN. Flexi Direct uses any third party SGSN, but the capacity and the con-

nectivity need to be considered. Flexi Direct enables high capacity user plane and does

not need SGSN in the user plane. SGSN supports Direct tunnel solution, where it pro-

cesses only the Iu-PS control plane. The Direct tunnel solution uses standard interfaces

Iu-PS and Gn, so it can be used with the current RNCs and GGSNs.

In Flexi Direct, Direct tunnel solution allows flat user plane traffic, whereby the user

plane connects directly from the Flexi Direct BTS to GGSN. Direct tunnel solution is

suitable for the low delay and high capacity networks, such as Flexi Direct.



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GGSN

Flexi Direct uses standard GGSN interfaces and any standard based GGSN. Flexi

Direct enables high capacity with low delay, therefore GGSN capability needs to be con-

sidered. Direct tunnel solution creates a direct tunnel from Flexi Direct BTS to GGSN.This means that while the user equipment (UE) is moving from Flexi Direct BTS to Flexi

Direct BTS (in FACH, DCH or in CELL_PCH state), it causes PDP context update to

GGSN. It is recommended that the operator checks the capacity of the third party GGSN

control plane when using the Direct tunnel solution. Nokia Siemens Networks GGSN

(Flexi ISN) is also optimized for control plane.

User Equipment, UE

All 3GPP standard compliant terminals can be used in Flexi Direct Network.

OMS

Nokia Siemens Networks Flexi Direct Operation and Management Server (OMS) is an

essential component in Flexi Direct operation and management architecture. OMS con-solidates operation and management traffic from Flexi Direct access network elements

before NetAct processing. In addition, OMS manages Flexi Multiradio BTSs and Flexi

Direct RNC (logical unit) under the control of NetAct.

OMS is a 1U high element that can be placed into a standard 19-inch rack in indoor envi-

ronment. The Figure 4 Nokia Siemens Networks Flexi Direct OMS shows the exterior

view of OMS.

Figure 4 Nokia Siemens Networks Flexi Direct OMS

OMS connects to the Flexi Multiradio BTS and Flexi Direct RNC through a BTSOM inter-

face and to NetAct through an NWI3 interface. BTSOM and NWI3 are efficient and

reliable management protocols developed by Nokia Siemens Networks.

OMS is capable of handling an access network with 1200 Flexi Direct BTSs. In mass

operations, parallel management operations can be ongoing to several network ele-

ments.

For more information on the role of OMS in network management, see Operability Over-

view.

NetAct

NetAct is a network and service management solution that consists of many tools for

handling a number of network elements and expanding networks. It is designed to be

able to handle an increase in both complexity of the network and amount of traffic and

data. With NetAct both the network and services within the network are managed cen-

trally, which means the operator can view the network element failures, service quality

indicators, and traffic on one screen.

The main NetAct functionalities are available for Flexi Direct are as follows:



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• NetAct performance management: functionality provides analysis data that indi-

cates the geographical areas where high speed data access is most needed and

used.

•NetAct Key Performance Indicators (KPIs) enable the operator to analyze the use ofFlexi Direct in their network. Operators can also follow the number of active Flexi

Direct capable mobiles and the typical behavior of the Flexi Direct subscribers in

terms of, for example, throughput or connection times.

• NetAct fault management and performance management functionalities together

can help operators guarantee end user access to the services through Flexi Direct,

thus improving subscriber perception of the service quality. Problems with, for

example, physical channels or priority settings, or in hard handovers (HOs), packet

transmission or serving cell changes can be detected and corrected without delay.

• NetAct Configuration management functionality is used to configure the Flexi Direct

network elements. This also includes the software and hardware management func-

tionality.



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2.3 Network deployment

Flexi Direct can be deployed in two main scenarios. The first one is greenfield Flexi

Direct without any other radio network layers and the other one is the case where the

operator is already having the existing WCDMA or 2G network.

PS only network

Terminals perform Flexi Direct layer selection based on the subscription data. Flexi

Direct layer selection is implemented by using location area rejection mechanisms as

per WCDMA network selection procedures or using equivalent PLMN codes. For

example, in location area rejection method, the routing areas (RA) must be the same in

the WCDMA and Flexi Direct networks. Flexi Direct requires careful study on the RA size

as paging causes excessive load if the RA is too wide. If the RA is too narrow, then ter-

minals send RA updates very often.

The main reason for keeping the Flexi Direct and other/regular subscribers in their own

carriers or network layers is to avoid unnecessary delays in the session set-up. Suchdelays occur when the terminal is first moved to the appropriate layer by using handover

and only then the data session or call starts. This is not desirable for the high-speed data

layer because it compromises the session set-up times (for example, TCP at the appli-

cation level).

2.3.1 Greenfield scenario

In this case the operator does not have any existing WCDMA/2G network and builds the

Flexi Direct network from scratch. Both CS and PS services can be fully supported in

Flexi Direct network. It is possible, however, to deploy PS only Flexi Direct network in

some of the greenfield deployment scenarios. Another option for the operators is to

convert the existing hot spot NodeB(s) to the Flexi Direct BTS(s).

Figure 5 Pure Flexi Direct Network

2.3.2 2G/3G network overlay scenario

In the second scenario, Flexi Direct data overlay network is built on top of the existing

networks.

In this case Flexi Direct works on its own radio carrier frequency or in the same fre-

quency as existing 3G network to enhance coverage and capacity.

Both CS and PS services are all supported by the Flexi Direct network. Mobility with

existing RNC-based 3G network is handled either as soft handover or hard handover.

Flexi Direct BTS supports 3GPP standard Iur interface towards the RNC and thus inter-

RNC soft handover and relocations between the Flexi Direct BTS and RNC are possible.

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Figure 6 Flexi Direct as data overlay network

2.3.3 Flexi Direct external interfaces

Flexi Direct network solution is visible to the surrounding networks by the following

standard interfaces:

• Iu-PS interface divided into two parts: – Iu-PS Control Plane between Flexi Direct BTS and SGSN

– Iu-PS User Plane

– Gn-u interface between Flexi Direct BTS and GGSN for user plane in case of

direct tunneling functionality

• Iu-CS

– Iu-CS Control Plane between Flexi Direct BTS and MSC server. Supported in all

deployments except for some specific greenfield scenarios (that is, PS only

network)

– Iu-CS User Plane between Flexi Direct BTS and Media Gateway (MGW),

required for CS voice support

• Iur

– Iur interface between Flexi Direct BTSs: vendor specific extensions on RNSAP

are used to optimize the mobility in the flat network.

– Iur interface between the Flexi Direct BTS and 3G RN. 3GPP Complaint Iur

(RNSAP) over IP is used.

– The maximum number of combined Iur interfaces supported by Flexi Direct is

32.

• Iu-PC interface between Flexi Direct BTS and SAS for Location services

• dedicated interface for O&M purposes:

– NWI3 is the NSN proprietary Network Management interface between OMS and

NetAct.

– BTSOM is the NSN proprietary management interface between Flexi Direct BTS

and OMS.

• Iu-BC is a logical interface between RNC and a cell broadcasting centre (CBC)

g The Iu-BC is one instance of an Iu interface and is used for cell broadcast services.

DHCP server is an optional element.

Flexi Direct supports Lawful Interception and Trace, SMS (Gd interface), and CAMEL

(Ge interfaces).

Macro Coverage (f1)Flexi Direct Coverage (f2)



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2.4 Capacity and efficiency

In Flexi Direct, Flexi Direct BTS implements the RNC functionality in the Flexi Direct

RNC. The Flexi Direct RNC can serve a single BTS capacity, therefore, there is no need

of higher capacity. Although a considerable number of Flexi Direct RNC connects to theSGSN, a lot of SGSN capacity is retained thanks to implementation of a direct tunnel

solution. With this direct tunnel solution user plane traffic is bypassed directly to GGSN.

The mobility inside the RAN is visible to the SGSN as SRNS relocation. In the Direct

Tunnel case, the mobility is visible also for GGSN as PDP context updates.

2.4.1 DC-HSDPA

Dual-Cell HSDPA uses two adjacent WCDMA carriers to transmit data for a single UE.

Together with 64QAM, peak bit rate is 42 Mbps.

Dual-Cell HSDPA can be used in the downlink direction for the UEs which have interac-

tive or background traffic to be scheduled. If conversational or streaming services areneeded, dynamic switching between single-carrier and dual-carrier modes is done.

2.4.2 Flexible RLC

This feature improves end user experience enabling higher bit rates for single users and

also the overall throughput in the network.

With the support of flexible RLC PDU instead of the fixed RLC PDU, the processing

requirements (UE and Flexi Direct RNC) and RLC PDU overhead are reduced. With

Flexible RLC feature, MAC-d header is not needed. The MAC-d multiplexing of logical

channels into the same transport block has been replaced by MAC-es multiplexing via

LCH-ID field.

2.4.3 Flexible Iu

Flexible Iu feature provides a standardized mechanism for connecting multiple MSCs

and SGSNs to an RNC within a single operator network. This feature introduces the

concept of Pool Areas. An UE roams freely within a Pool Area (in either connected or

idle mode) without the need to change the CN serving node. Pool Area configurations

are made in the CN nodes. Pool Areas themselves are not visible to the RAN, but the

RNC configuration has to be configured according to the CN Pool Area configurations

so that the RNC is able to route signaling messages to any CN node within a Pool Area.

The NAS Node Selector function (NNSF) is used for selecting the CN node for the UE.

The UE derives the value of the parameter NRI from the P-TMSI or IMSI and sends theNRI to the RNC in the Initial Direct Transfer message. The RNC selects the CN node

corresponding to the NRI value configured in its database. The NNSF in the RNC

contains also the CN node recovery functionality, which balances the load between the

CN nodes of a pool in different cases, for example, with CN node failure, SW/HW update

or adding or removing a CN node to/from the pool.

2.4.4 HSPA 72 Users Per Cell

This feature increases the number of simultaneous HSPA (HSDPA and HSUPA) users

to 72 per cell, both with dedicated and shared scheduler. To allow scheduling and

control of increased number of HSPA users in a cell, the number of HS-SCCH channelsis increased to four.



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2.4.5 Common Channel Setup

In this feature the SRBs will be mapped to the RACH/FACH (CELL_FACH RRC state)

and this leads to the processing improvement in the BTS and Flexi Direct RNC. Also the

setup times are reduced as no dedicated radio links are activated during the RRC con-nection setup procedure phase.

2.4.6 Multi-Operator Radio Access Network

Multi-Operator RAN (MORAN) allows up to four operators to share radio access

network. Operators use their own frequencies and own PLMN-id. Solution is compatible

with 3GPP standard and it is supported with all 3G terminals. MORAN solution allows

independent control of traffic for each operator; they have dedicated cell level parame-

ters. They can also add own BTSs under the shared RNC where needed. All operators

have their own interfaces towards the CS and PS core network. The subscribers of dif-

ferent operators use cells in different carrier layers (frequencies). The differentiation is

based on the Mobile Country Code (MCC) and Mobile Network Code (MNC) of the cell.

Each cell has MCC and MNC corresponding to the operator. This feature is compatible

with R99 and R4 Core Networks. This solution allows operators to individually plan and

optimize their own cell parameters whereas planning and dimensioning of global RNC

parameters, BTS, RNC, and transmission capacity need to be handled in cooperation.

Sharing the RAN gives the operators freedom in defining the scope of their cooperation

and determining when and where they want to provide additional capacity or coverage

of their own.

2.4.7 Multi-Operator Core Network

Multi-Operator Core Network (MOCN) is a 3GPP solution for RAN sharing. The PLMN-identities of available CN operators are broadcasted to UEs in the system information

messages. The 3GPP R6 capable UEs choose the PLMN to which the Flexi Direct RNC

should start the signaling connection. The chosen PLMN is signaled to the Flexi Direct

BTS in the Initial Direct Transfer Message and based on the selected PLMN the signal-

ing connection is routed directly to the appropriate CN.

In this release Adapter can be connected to 16 SGSNs in the PS domain and up to 16

MSC/MGW in the CS domain. These can be shared between 1 to 4 operators.



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Mobility

3 Mobility

3.1 Mobility managementFlexi Direct is a fully mobile solution. Flexi Direct supports the following kinds of mobility:

• Intra-system handover within the Flexi Direct

– Intra-system handover with Iur

– Intra-system handover without Iur

• Inter-system handover between the Flexi Direct and a traditional 3G network

• Inter-system handover between Flexi Direct and 2G

The basic feature set for mobility includes:

• intra-system handover between Flexi Direct BTSs

• Soft handover based on detected set reporting

• 3G inter-system Handover the same as normal RNC relocation

• HSUPA handover

• Paging for terminals in URA_PCH state

• HSPA capability based handover

• Inter-frequency handover

• load and service based IS/IF handover

• IMSI based handover

Inter-system handover between Flexi Direct and the traditional WCDMA RAN is the

same as the normal RNC relocation in the WCDMA network. Inter-system handover

from the Flexi Direct to the other IP-based access networks, such as WLAN, takes place

on the IP level.

Flexi Direct uses standard terminal SIM or U-SIM cards that support normal global

roaming. In case of non-Flexi Direct WCDMA networks of other operators the Flexi

Direct user or a terminal uses normal roaming procedures and agreements between the

operators. While the terminal moves inside the Flexi Direct, the PDP address always

remains the same and the IP stack of the terminal does not need to notice the mobility.

Terminal mobility in Flexi Direct uses standard Iu-PS interface towards SGSN and Iur

interfaces in case of mobility between Flexi Direct BTSs. This allows efficient reuse of

SGSN and GGSN. SGSN supports Direct tunnel solution where it processes only the Iu-

PS control plane. The Direct tunnel solution uses the standard interfaces Iu-PS and Gn,

therefore it can be used with the existing SGSN and GGSN.

Figure 7 Flexi Direct mobility - Gn based illustrates Gn based mobility in the Flexi Direct

System.



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Figure 7 Flexi Direct mobility - Gn based

3.1.1 Intra-system handover with Iur

In Flexi Direct System the intra-system handover procedure for the HSPA bearers is dif-

ferent from the 3GPP standardized SRNS relocation procedure. The main difference is

that radio links between UE and initial Source Adapter are not released after SRNS relo-

cation is completed. However, the radio links are actually retained after relocation for

bearers mapped to the DCH transport. The Idea behind this solution is to keep UE in UL

synchronization on those radio links to facilitate fast backward relocation if it is required.

This means that while there is a hard handover switching of user DL traffic on HS-DSCH,

soft handover state for bearers mapped to DCH transport is still maintained after com-

pletion of Serving Adapter change (SRNS relocation).

This feature is not standardized in 3GPP and requires extensions in RNSAP to support

this handover.

3.1.2 Intra-system handover without Iur

This feature enables basic mobility between Flexi Direct RNC without Iur interfaces. This

feature enables direct mobility between the high speed downlink shared channel (HS-

DSCH) in one cell to the other. Flexi Direct uses standard Hard Handover between the

Flexi Direct BTSs (UE involved Inter Adapter Relocation).

3.1.3 Soft Handover Based on Detected Set Reporting

A detected set is a set of cells that are detected by the UE, but are not included in the

neighbor cell list of the UE or the current active set. Detected set reporting is a 3GPP

functionality where the network commands the UE to report the detected set. Detected

set reporting is applicable to intra-frequency measurements made by the UE in the

Cell_DCH state.

This feature allows the operator to define 32 additional neighbors. These additional

neighbors are added on the top of the up to 32 normal neighbors that are signaled to the

UE. Additional neighbor list is not signalled to the UE, but if UE reports one or more of

these additional neighbor cells' scrambling code in the detected set report, RNC consid-

ers those as soft handover target cells in addition to normal neighbors. This means that

effectively each cell can have 64 neighbors: 32 neighbors that are signaled to the UE

and additional 32 ones which are not signaled.

SGSN

Flexi Direct BTS

Flexi Direct BTS

GGSN

Iur

Gn (GTP-C)

Gn (GTP-U)

IuPS (C)

Gi



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Mobility

3.1.4 Inter-frequency handover over Iur

This feature is useful when the D-RNC or CN does not support SRNS relocation.

Case 1: The Iur interface between the two Flexi Direct BTSs is used when the CN (MSC

/SGSN) to which it is connected does not support SRNS relocation.

Case 2: The Iur interface between the Flexi Direct BTS and RNC is used when CN or

D-RNC does not support the SRNS relocation. Flexi Direct BTS always supports SRNS

relocation. Inter-frequency handover over Iur is needed when there are isolated cells,

for example indoor cells, in a carrier under the DRNS or if carrier has a dedicated RNC.

The Serving Flexi Direct RNC (SRNC) and Drift Flexi Direct RNC (DRNC) support the

following inter-frequency handover signaling procedures over Iur:

• inter-frequency handover within DRNS when all radio links in the active set are con-

trolled by the target DRNC

• inter-frequency handover from the SRNS to the DRNS when one or more radio link

in the active set is controlled by the target DRNC • inter-frequency handover from the SRNS to the DRNS when no radio link in the

active set is controlled by the target DRNC

• inter-frequency handover from the DRNS back to the SRNS

• inter-frequency handover between two DRNSs when no radio link in the active set

is controlled by the target DRNC

3.1.5 Inter-system handover between the Flexi Direct and WCDMA RAN

Flexi Direct RAN can be in the same or different frequency layer. Its interface to WCDMA

RNCs based on standardized Iur interface. The intra-frequency and inter-frequency

mobility procedures are supported between the Flexi Direct and the WCDMA RAN.

When the Iur interface is commissioned between the Flexi Direct and WCDMA RAN, soft

handover procedures shall be supported for the Signaling Radio Bearers (SRB) and

Radio Bearers (RB) mapped to the DCH transport channel.

When the Iur interface is not commissioned, UE involved SRNS relocation is triggered

in all the scenarios involving only PS RAB(s). When the UE is allocated both CS and PS

RAB(s), the PS RAB(s) are reconfigured to the DCH/DCH before the relocation is trig-

gered.

3.1.6 Mobility between Flexi Direct and 2G network

The mobility procedures supported between WCDMA RNC and 2G network will be

applicable also for Flexi Direct RAN and the 2G Network.

Multiple BSIC Identification function is used as well. When an inter-system handover

from WCDMA to GSM may fail if the initial BSIC identification of the best GSM cell

(according to the GSM RSSI measurements) fails, or the target GSM cell is fully loaded.

Instead of waiting the penalty period and then retrying the handover with new com-

pressed mode measurements, the BSIC identification for more than one GSM cell is per-

formed. This increases the probability of successful BSIC identification and allows

another handover attempt to the second or third best cell without repetitive GSM mea-

surements if the first handover attempt fails.

In order to enable the handover attempt to the second or third best GSM cell, the RNC

selects two or three GSM target cells which meet the required radio link properties.



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3.1.7 Mobility between Flexi Direct and LTE

During LTE rollout phase interworking is supported and WCDMA services can be

provided for LTE users in the areas where LTE is not yet available. LTE interworking

feature introduces priority based algorithm for idle mode cell reselection. Operator isable to prioritise WCDMA, LTE and GSM with eight distinct priorities (different Radio

Access Technologies must have different priorities). UE currently camped in WCDMA

will periodically measure any higher priority RATs. Any priority RATs will be measured

when WCDMA quality criteria fall below a threshold.

LTE to WCDMA PS handover functionality allows for service continuity of data services

with minimal interruption time when changing from a LTE cell to a WCDMA cell. LTE is

controlling when the handover is triggered and what are the possible WCDMA targets.

Multi-RAB handover from LTE to WCDMA is supported.

3.1.8 HSPA Capability Based Handover

This feature enables UE-and-cell-capability-based handover to HSPA layer. The inter-

frequency handover is periodically triggered for the HSPA capable UEs if the source cell

has suitable target candidates in the inter-frequency neighbor list. The candidates for

the handover are defined by the operator and they can be also from another BTS. The

HSPA capability of the source cell does not have impact, that is, source cell can be with

or without HSPA capability.The handover measurements for handover to HSPA layer

are triggered only in case the UE has an active service, which is allowed to perform

HSPA-capability-based handover. These services are defined by the operator. The

handover is performed directly to the HSPA channels on another frequency layer.

3.1.9 Load and service based IS/IF handover Load- and-service-based handovers (HOs) handle load sharing and service differentia-

tion inside the WCDMA system as well as between WCDMA and GSM/GPRS systems.

Both load and service are taken into account simultaneously, but the measured load

defines the way of operation.

The load indicators that can be measured are uplink (UL)/downlink (DL) interference,

non-real time (NRT) traffic delay, DL spreading code availability and HW/logical

resource usage.

This feature also enables the operator to set different HO profiles for the service classes.

The service classes are split according to the traffic classes specified for radio access

bearers (RABs), separating the speech and data services from the CS and PS domains.

The Flexi Direct-RNC-based HO profile defines the preferred system (WCDMA, GSM)

or WCDMA hierarchical cell layer (GSM, WCDMA macro, WCDMA micro, none).

3.1.10 IMSI-based handover

The purpose of the IMSI-based handover feature is to be able to command a mobile

subscriber visiting another network to make handover measurements only to cells which

belong to specified PLMNs. Accordingly, in such a scenario the mobile subscriber can

only be handed over to those specified (home or authorized) PLMNs. The input for the

selective measurement control is the PLMN id that is included in the IMSI of the sub-

scriber.



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Mobility

IMSI-based handover benefits the geographical sharing and common shared RAN

concepts by enabling directed handovers from the shared WCDMA network to either the

subscriber's home network or to another authorized WCDMA or GSM network when

coverage becomes available. The functionality in these RAN-sharing concepts without

IMSI-based handover is that the same handover paths are allowed for all users and

mobiles have to find the correct network outside the active call state.

3.1.11 Inter-frequency handover

This feature introduces inter-frequency compressed mode measurement and handover

capability directly from HSDPA to HSDPA. This feature improves the user experience

because of faster HSDPA inter-frequency handover and higher data throughput during

the compressed mode. The target cell can be in the same Flexi Direct RNC or the neigh-

boring one, that is both Intra and Inter Adapter scenarios are supported. This feature is

also supported towards the 3G RNC.

Without this feature, the IF handover would require reconfiguration of the UE to the DCH

transport. This is required to start the compressed mode for the inter-frequency mea-

surements in the UE.

The following cases are possible:

• DCH/HSDPA to DCH/DCH

• DCH/HSDPA to DCH/HSDPA

• DCH/DCH to DCH/HSDPA

• DCH/DCH to HSUPA/HSDPA

3.1.12 HSPA over Iur in Flexi Direct BTS

This feature improves end-user performance by enhancing the data throughput in case

of inter-Flexi Direct BTS mobility.

The UE's intra-frequency measurements indicate that the strongest cell in the active set

is under the DRNC, HSDPA and HSUPA serving cell change over Iur is performed. After

the serving cell change, HSDPA and HSUPA data is transmitted over the Iur using

HSPA congestion control. The serving cell change over the Iur can also be performed

between cells controlled by DRNC. When the last active set cell in the SRNC is deleted,

UE not involved SRNS relocation is triggered while HSPA service is in use. In case of

failure or no SRNS relocation supported by DRNC/core network, channel type switch to

DCH is triggered. Also HSDPA with DCH in UL configuration is supported if HSUPA

cannot be used.



DN0931126 29

Flexi Direct System Description Voice Service support

Id:0900d8058096793b

Confidential

4 Voice Service supportFlexi Direct provides voice services through the following ways:

• CS AMR Voice support in Flexi Direct BTS • VoIP

4.1 CS AMR Voice support in Flexi Direct BTS

Flexi Direct System provides a basic CS AMR voice support. It is required for the voice

services that the Flexi Direct System supports the IuCS user plane over IP with the

Media Gateway (MGW).

Flexi Direct network supports the following codec sets:

• AMR Codec Sets:

– (12.2, 7.95, 5.90, 4.75)

– (5.90, 4.75)

• Wideband AMR Codec Set:

– (12.65, 8.85, 6.6)

Flexi Direct network supports HSDPA/HSUPA with Simultaneous AMR Voice Call.

When the Terminal establishes CS AMR services, mobility procedures applied are as

per traditional WCDMA RAN (for example anchoring and UE NOT Involved Relocation).

Mobility with CS AMR service will be the same towards WCDMA network as inside the

Flexi Direct network.

The CS Voice over HSPA feature extends the UE talk time more than 50%, improving

the end user experience and increasing the operator's voice call revenues. End user

experience is also improved thanks to faster call set-up times. Voice over HSPA reduces

the call set up time by approximately 50%. Using the high spectral efficiency of HSPA

channels for AMR calls can increase the radio interface capacity up to 50%, leading to

CAPEX savings.

4.2 VoIP

Flexi Direct implements a PS optimized network, which can be used also for Voice over

IP (VoIP). It is possible to provide VoIP services in Flexi Direct network with different

messenger applications. These services are handled as non real-time call in the radio

interface.

4.3 HSDPA/HSUPA with simultaneous AMR support

The UE does not need to be transitioned to the DCH transport channel for the ongoing

HSDPA/HSUPA bearers when the CS voice call is initiated. This ensures that an AMR

voice call initiation does not influence the HSDPA/HSUPA service data flow.



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Location services (LCS)

5 Location services (LCS)Location services (LCS) provide the operators with mechanisms to locate the mobile

subscribers, thus enabling the provision of location applications. The network provides

location applications with the geographical area (shape) that describes the location of

the UE. The location application processing this information resides either within or

outside the wireless network, for example Public Safety Answering Point (PSAP). The

network or an external application initiates a request for Flexi Direct capable UE posi-

tioning.

Flexi Direct supports some of the 3GPP UTRAN LCS methods. The methods provide

different levels of accuracy in different environments. Flexi Direct uses following LCS

methods:

• Cell coverage-based with geographical coordinates. It is used as a fallback method

if A-GPS method fails. This CI+RTT method covers also Service Area Identifier

(SAI) method. The CI+RTT position is also used as a reference position for deter-mining appropriate assistance data needed for A-GPS (therefore, CI+RTT is a pre-

requisite for A-GPS).

• Assisted GPS. Flexi Direct supports UE-and-network based solution and IuPC inter-

face to Stand-alone A-GPS SMLC (SAS).

• LCS Support in Drift RNC introduces positioning information transfer over the Iur in

the RNSAP radio link handling response messages. Serving RNC/Flexi Direct BTS

may use the information to provide location report towards the CN when anchoring

concept dominates. If the positioning is required in the serving RNC/Flexi Direct

BTS, in anchoring cases, the serving RNC/Flexi Direct BTS always uses the cell

identifier (CI) based method and passes the coordinates received from the drift

RNC/Flexi Direct BTS to the CN.

• SAS-centric Iupc mode is 3GPP R7 Positioning Calculation Application Part (PCAP)

protocol feature. SAS-Centric Iupc allows a new functional split between RNC/Flexi

Direct RNC and Stand-alone SMLC (SAS). In the SAS-centric mode of operation the

SAS selects the used positioning method, triggers the required measurements and

determines the positioning result. A set of new procedures has been defined to

enable the positioning method selection and calculation in the SAS. This new func-

tional split is not visible to the BTS or the UE.

The above methods ensure the full service coverage and availability for all the environ-

ments.



DN0931126 31

Flexi Direct System Description Location services (LCS)

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Figure 8 Location services for Flexi Direct

Position activation and reporting messaging are supported over Lg and IuPS interfaces

between GMLC, SGSN and Flexi Direct RNC. LCS system sees Flexi Direct RNC as

RNC that supports only single Flexi Direct BTS. Flexi Direct RNC supports also IuPC,an

LCS-specific interface, providing support for location services.

Iu-PC, which is a point-to-point logical interface, connects external GPS data reference

network node (SAS) to Flexi Direct BTS. LCS signaling is performed in the following

sequence:

PSAP requests UEs location from GMLC.

2 GMLC seeks the correct SGSN node and requests UEs position from SGSN withMAP: Provide Subscriber Location.

GPS reference

Network

HLRStand-AloneSMLC (SAS)

IuPC/ADIF

Flexi Direct BTS

GMLCSGSNFlexi Direct BTS

RDF

LRF

ECS

GPS referencefrom satellite

E2

PSAP

Lg

Gr

Iu-PS

3 5

2

1

4

1. PSAP sends location update request to GMLC.2. GMLC requests SGSN address.3. GMLC sends MT-LR to RAN via SGSN.4. Flexi Direct RAN sends A-AGP MT-LR to the terminal with assistant

GPS location information from GMLC. Terminal responses with locationinformation as (,Y) and it is sent to the SGSN.

5. GMLC receives location information and sends it to PSAP. Locationinformation is in (X,Y) format.

SIP



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Location services (LCS)

3 SGSN receives the request from GMLC and SGSN verifies that UE privacy is over-

ridden by the emergency services provider.

4 After proper user position requestor authentication, SGSN sends RANAP: Location

Reporting Control to Flexi Direct RNC indicating the start of location procedure.

5 Flexi Direct RNC verifies if UE is in dedicated channel and initiates cell-based

location procedure to achieve initial estimate of UEs location. If cell-based location

procedure cannot provide sufficiently accurate position estimate, Flexi Direct RNC

initiates GPS assistance data retrieval procedure from SAS, which is based on initial

UE location estimate.

6 The assistance data received from SAS is forwarded to UE in RRC Measurement

Control. The data contains a command to initiate UEs internal positioning measure-

ment that uses given assistance data and UE integrated GPS capabilities.

7 The received UE position estimate with RRC Measurement report, based on GPS

System, is returned to PSAP via Flexi Direct RNC, SGSN, and GMLC. If GPSsystem is unable to calculate UEs position for any reason, cell-based positioning

estimate is used instead.



DN0931126 33

Flexi Direct System Description Paging in Flexi Direct Network

Id:0900d8058096c553

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6 Paging in Flexi Direct NetworkFlexi Direct supports all the RRC states including URA_PCH state. URA_PCH state is

supported in Flexi Direct network to decrease the mobility load for the core and Flexi

Direct BTS. In the URA_PCH state the UE can change the cell in the UTRAN Registra-

tion Area (URA) without generating any mobility event towards the core network. Paging

over Iur is also supported for handling overlapping URA across adapters.

The concept of URA overlapping across Flexi Direct BTS borders is used, where neigh-

boring Flexi Direct BTS cells can belong to the same URA-IDs. If the URA does not

change, the fast moving UE in URA_PCH state crosses Flexi Direct BTS borders without

informing the network about its current cell. The use of overlapping URAs prevents

some unnecessary SRNC relocations. Also a relocation "ping-ponging" of the mobiles

(in RRC states other than Cell_DCH) can be avoided when the source Flexi Direct RNC

relocation procedure is not initiated immediately after the UE has moved to the drift Flexi

Direct RNC.

6.1 Paging Optimization in Flexi Direct Network

In normal paging, MSC/SGSN has to distribute the RANAP paging message to all the

Flexi Direct BTS part of the LA/RA to initiate paging for the UE in the RRC IDLE mode.

This leads to the increase in the signaling load in the Core network. To reduce the

paging load in the core network, Flexi Direct RAN supports paging optimization solution.

The Paging Optimization solution happens according to the following scheme:

• Each Location Area/Routing Area is divided into paging groups where each Paging

Group has one Paging Master(PM) and one Paging Standby (PS).

• Several Flexi Direct BTSs are grouped to form a paging group.

• One of the Flexi Direct BTSs in the paging group is configured as paging master.

• For the redundancy purposes, another Flexi Direct BTS in the paging group is con-

figured as paging standby.

• Both paging master and paging standby need to have Iur connection to other Flexi

Direct BTSs in the paging group.

• The MSC and SGSN are also configured with the paging group Information.

• MSS/SGSN sends RANAP Paging to all the paging masters (if they are available)

in the Location Area Code (LAC)/Routing Area Code (RAC).

– If a paging master in a certain paging group is down, MSS/SGSN sends RANAP

paging to the paging standby Flexi Direct BTS.

– If both paging master and paging standby Flexi Direct BTSs in a certain paginggroup is down, MSS/SGSN sends RANAP paging to all the alive Flexi Direct

BTSs in that paging group.

• Each paging master/standby coordinates paging and sends paging to own cells. In

case UE is not found in the paging Flexi Direct BTS, the RNSAP paging message is

forwarded over the Iur interface to other Flexi Direct BTSs in its own paging group.

• Flexi Direct BTSs receiving Iur paging messages coordinate paging and send to

their own cells.



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Paging in Flexi Direct Network

Figure 9 Paging Optimization

g The Paging Optimization is a Nokia Siemens Networks proprietary feature that works

only with the Nokia Siemens Networks Core(MSC/SGSN).

6.2 Paging Channel with data rate of 24 Kbps

In Flexi Direct, the Paging Channel data rate is increased to 24 Kbps. This eases paging

message congestion and thus improves the end-user experience when the number of

subscribers and call attempts increases.The PCH data rate is increased to 24 kbps. This is achieved by using 240 bits Transport

Block Size (TBS) with 10 ms Transmission Time Interval (TTI).

With the 24 Kbps configuration, the PCH is mapped on a dedicated Secondary Common

Control Physical Channel (SCCPCH). This means that two SCCPCHs are needed in a

cell: one for Forward Access Channels (FACHs) and other for Paging Channel (PCH).

SCCPCH for 24Kbps PCH requires SF128 code channel.

Flexi Direct BTS

MSS

transat on(CS call, SMS)

Paging Group (1)Iur Paging

Paging Group (2)Iur Paging

Paging Group (n)Iur Paging

LAC1

LAC1:Flexi Direct BTS1, Flexi Direct BTS2, ...Flexi Direct BTS100

Flexi Direct BTS Flexi Direct BTS

Iu Paging



DN0931126 35

Flexi Direct System Description Radio resource management in Flexi Direct

Id:0900d8058096c555

Confidential

7 Radio resource management in Flexi DirectFlexi Direct brings benefits to both the operators and the end users. In practice, Flexi

Direct offers higher data rates to end users, larger coverage areas especially for high bit

rates, lower delay in case of transmission failures, larger capacity in the radio network,

and the opportunity for the operator to deliver services – the existing ones and the new

ones – at a lower cost of bit. Most of the benefits are guaranteed thanks to radio

resource management functionalities which is a set of Flexi Direct system functions

used for the establishment, maintenance, and release of radio connections needed by

the system.

7.1 MIMO feature

MIMO feature enables high HSDPA bit rates. It leads to subscription differentiation and

additional data service revenue. The feature leads not only to the enhancement of single

user peak rate, but it also increases the average cell throughput. Thus, both end-userexperience and overall network efficiency get improved.

2x2 MIMO uses two transmit antennas at the BTS and two receive antennas at the UE.

MIMO has two operational modes. In dual stream mode two parallel data streams carry

different data. This allows two times higher peak bit rate compared to same case but

without MIMO. In single stream mode MIMO does not increase the peak rate. However,

it improves the radio conditions for MIMO UEs, as UE can choose from four different

beams from the NodeB. The beams are created with a phase shift in the signal between

the two transmitting antennas.

HSDPA Rel8 terminal categories 19 and 20 support MIMO with 64QAM. For supporting

UEs, NodeB will use MIMO single stream mode in bad and average radio conditions.

With good radio conditions, NodeB switches to dual stream mode. In extremely good

conditions dual stream mode is used together with 64QAM modulation, enabling the

best possible bit rates up to 42 Mbps.

7.2 Fast Dormancy

Fast Dormancy feature saves signaling load compared to proprietary "fast dormancy"

implemented in many smart phones. Also user experience is improved thanks to faster

setup from Cell_PCH state compared to idle. Battery saving is similar to proprietary "fast

dormancy".

Fast dormancy is an optional feature for UEs in 3GPP Release 8. There is a new UE

"Signaling Connection Release Indication Cause" in SIGNALLING CONNECTION

RELEASE INDICATION. This cause indicates to the network that the UE has deter-

mined it has concluded active PS data transfer.

Upon reception of this Information Element the RNC will trigger an RRC State transition

to Cell_PCH instead of letting the UE to go to idle mode. URA_PCH state may be

selected for fast moving UE. Cell_PCH has a very low battery consumption, and send-

ing/receiving data requires only a fraction of the signaling compared to starting from idle

state. Also HSPA setup is faster from Cell_PCH or URA_PCH state compared to RRC

idle.

Some smart phones ignore network timers to move to Cell_PCH state, and instead

move directly to idle. Such terminals cause a huge unnecessary signalling load to the



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Radio resource management in Flexi Direct

network. UEs supporting fast dormancy can be controlled by network and yet save bat-

teries.

7.3 HSUPA interference cancellation receiver HSUPA Interference Cancellation enables higher HSUPA throughput especially in

typical data and voice mixed scenario. It allows high Ec/No for a high data rate 2 ms

HSUPA user while keeping the noise rise within the planned limits. Cell coverage is

therefore not compromised due to the high rate user.

Without IC even a single 2 ms user either could not reach a high bit rate or would shrink

the cell easily by 6 dB beyond the planned minimum coverage. Note that IC reduces

interference caused by other users on own signal, while RAN1702 Equalizer reduces

interference caused by own signal in multipath channel.

HSUPA Interference Cancellation removes the interference originating from other UEs

in 2 ms TTI UEs. The 2 ms TTI UEs are first received with a regular rake receiver or withFDE. Next, turbo decoding is performed and the decoded data, seen as interference by

other users is used to reconstruct the original signal. Reconstruction includes turbo

encoding, spreading and modulation. The reconstructed signal, interpreted as interfer-

ence to the other UEs, is subtracted from the original antenna signal. thus, the UEs

received from the residual signal benefit from lower interference level. As a result,

coverage and capacity gains for the cell can be achieved.

7.4 Frequency Domain Equalizer

Frequency Domain Equalizer (FDE) is an enabler for high uplink data rates up to 11

Mbps (with 5 MHz) or 23 Mbps (with 10 MHz) with 16QAM. FDE reduces the interfer-

ence from multipath components of user signal. This solution is especially beneficial to

HSUPA with short spreading codes.

FDE is the same solution as in 3GPP LTE utilizing frequency domain equalization. FDE

is simpler compared to traditional time domain equalizer. It captures the energy from all

multi paths and offers robust performance in all channel conditions with up to 2x higher

16QAM data rate compared to Rake receiver.

FDE efficiently removes inter-symbol interference arising from user's own signal due to

multipath propagation. Rake receiver is unable to receive high data rates even in total

absence of other cell interference, since the short spreading codes with high HSUPA

data rates are vulnerable to inter-symbol interference. FDE can remove the inter-symbol

interference, leaving other users of the same cell and surrounding cells to be the main

limiting factors for UL data rates.

Interference from other users of the own cell can be alleviated with HSUPA interference

cancellation. FDE and IC can be operated in the same cell at the same time.

7.5 Extension of RNC identification numbers

This is a 3GPP Release 7 enhancement for flat architecture to enable up to 64 thousand

Flexi Direct BTS/Flexi Direct RNC in the network. RNC ID limit is increased from 4 to 64

thousand network elements. In Flexi Direct system the RNC ID defines Flexi Direct RNC

ID and RNC ID limit defines maximum number of Flexi Direct RNC in the network. For

the enhancement to be functional only the core network needs to support the RNC ID



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Flexi Direct System Description Radio resource management in Flexi Direct

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limit extension. Other elements such as mcRNC and IPA-RNC do not need to support

the extension for the feature to take effect.



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Transport

8 Transport

8.1 Flexi Direct transportFlexi Direct uses IP-based transport interfaces. It supports Iu-PS, Iu-CS, Iur, Iu-PC, Iu-

B, and DCN interfaces over IP. Flexi Direct handles terminal mobility by utilizing Iur inter-

faces between Flexi Direct BTSs, and between Flexi Direct BTS and RNC. Standard Iu-

PS and Iu-CS interfaces are used towards the core network. The concept allows efficient

reuse of MSS, MGW, SGSN and GGSN. Flexi Direct System also supports the Flexi-

Packet Radio microwave system which can be connected directly to the Flexi Direct BTS

ethernet interface.

8.1.1 Transport interfaces

In Flexi Direct RU30 logical Interfaces (that is Iu-PS, Iu-CS, Iur, Iu-PC, Iu-BC and DCN)are all supported with the FTLB tranport module. Network operator can select among

the following transport options for them:

• all logical interfaces mapped as IP over Ethernet

• all logical interfaces mapped as IP over AAL5/ATM/PDH (Iu-BC interface is not sup-

ported in this transport option)

Synchronization

In any case ToP will be available only as IP over Ethernet. Synchronous Ethernet is not

supported in Flexi Direct RU30.

For the ATM transport option, the network synchronization is usually delivered to the

BTS via PDH interfaces.

Ethernet and ATM transport interfaces

The interface towards the transport network can be established over Ethernet or

TDM/ATM. The Flexi Transport sub-module FTLB in Flexi Direct BTS utilizes both trans-

port options.

Ethernet

For an Flexi Direct BTS without activated Basic Ethernet switching, one GE port of the

FTLB unit is used for Iu-PS, Iu-CS, Iur, Iu-BC, DCN, and Iu-PC. In case Basic Ethernet

switching is used all three external Ethernet ports of the FTLB can be activated. The

actual port(s) to be used is/are arbitrarily configurable in the BTS.

Local Management of the BTS and of the adapter is done via the BTS local management

port.

No physical layer redundancy (board or port) is provided at transport level.

Ethernet link aggregation is also not supported. However, SCTP multi-homing is a sup-

ported functionality that has self-healing capabilities in case of connectivity loss for C-

Plane.

ATM

The ATM transport option is supported only on PDH interfaces: up to 4 E1/T1/JT1 ports

are present on the FTLB unit in addition to the Ethernet ports.



DN0931126 39

Flexi Direct System Description Transport

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When using E1, T1 or JT1, it is possible to use Inverse Multiplexing ATM (IMA) within

suitable subsets of the physical ports on the respective Exchange Termination (ET).

The IMA functionality which that is included in all interfaces can be set on and off by

software settings. It is supported according to ATM Forum Recommendation AF-PHY-0086.001.

The ATM support consists of a configurable number of AAL5 PVCs encapsulated in a

single ATM VP.

8.1.2 Flexi Transport Sub-Modules (FTM)

FTLB is the Flexi Transport submodule used for the Flexi Direct BTS. It has 2xGEe,

1xGEo and 4xE1/T1/JT1 interfaces. It supports ToP and IPsec as well.

8.1.3 Control plane protocols

Figure 10 Iu-CS, Iu-PS and Iur Control Plane represents the control plane protocol

stacks for Iu-CS, Iu-PS, and Iur interfaces. The higher layers protocol applies to both “IP

over Ethernet” and “IP over ATM” transport solution. The lower protocol layers are dif-

ferent for “IP over Ethernet” and for the “IP over ATM” transport option. These two alter-

natives are represented by different colors.

The Control Plane provides:

• control signaling protocols for packet-switched/circuit-switched service manage-

ment, user management and resource management.

• transport signaling protocols for the allocation of the bearers between the Flexi

Direct BTS and the MSC in the case of a circuit-switched domain.

• transport signaling protocols for the activation of the PDP context between the FlexiDirect BTS and the SGSN in the case of a packet-switched domain.

Figure 10 Iu-CS, Iu-PS and Iur Control Plane

8.1.4 User plane protocols

The figures reported in this subsection represent the Iu-CS, Iu-PS, and Iur interfaces

protocol stacks for both IP over Ethernet and IP over ATM transport options.



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Transport

8.1.4.1 Iu-CS higher level

Real-Time Transport Protocol (RTP) is supported according to IETF RFC3350 and

3GPP TS25.414. Encryption is not required for RTP as, it is provided by the lower layers.

The transmitter indicates that RTP version 2 is used. The receiver reports an error if theversion number is different and ignores the packet. The receiver accepts packets that

contain padding.

Figure 11 Iu-CS User Plane

8.1.4.2 Iu-PS higher level

GPRS Tunneling Protocol (GTP) at the Iu-PS interface: a connection-oriented data

bearer is obtained forming a tunnel between the Flexi Direct BTS and the SGSN. Thistunnel is then extended from the SGSN to the GGSN. If the direct tunnel feature is

active, this tunnel is established directly between the Flexi Direct BTS and the GGSN.

Figure 12 Iu-PS User Plane



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8.1.4.3 Iur higher level

The Flexi Direct BTS at Iur uses multiple local UDP ports, one per bearer. The selected

UDP ports are used as destination and source ports in the ingress and egress directions

respectively.

Figure 13 Iur User Plane

8.1.4.4 Iu-PC and O&M interfaces

Both the Iu-PC interface, between Flexi Direct BTS and the Stand-alone A-GPS Serving

mobile location centre (SAS), and the O&M interfaces, between Flexi Direct BTS and

OMS/NetAct, are based either on IP over Ethernet or IP over ATM (IPoA) transport

option as shown in the following figures:

Figure 14 Iu-PC interface



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Transport

Figure 15 O&M interfaces

For Iu-PC there is one single-homing association between the Flexi Direct RNC and

SAS. Please note that Iu-PC is only control plane, no separate user plane connection is

needed. Iu-PC can use the same source IP and network path as for example Iur CP in

Flexi Direct RNC.

8.1.4.5 Iu-BC interface

The Iu-BC interface is a logical interface between an Flexi Direct RNC or RNC in the

radio access network and a cell broadcast centre (CBC) in the core network, in its broad-

cast domain. Iu-BC is one instance of the Iu interface and is used for the cell broadcast

services.

Operator can run Iu-BC interface directly over Ethernet without any additional equip-

ment, like for example ATM based IP router.

Figure 16 Protocol architecture for the Service Area Broadcast with IP over Ethernet.

The Iu-BC interface protocol architecture consists of two functional layers:

• the radio network layer containing the user plane protocol service area broadcast

protocol (SABP),

• the transport network layer contains protocols related to transporting the user data.

In the transport network user plane, the path protocol used is TCP/I. It is used as the

bearer for the radio network layer protocol over the Iu-BC, IPv4 is supported.

In the radio network layer SABP is used between the Flexi Direct RNC or RNC and CBC

for both data transfer and signaling. There is no clear separation of control and user

planes.





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Transport

• synchronization from 2.048MHz G.703 signal

• synchronization from TDM traffic interfaces

• synchronization from Ethernet interface: Timing-over-Packet

Timing over Packet synchronization

“Timing over Packet” (ToP) feature is provided as Flexi Direct BTS Network Element

needs a reference clock for running air interface with the required frequency accuracy

when Ethernet transport interfaces are used instead of PDH ones.

ToP synchronization feature permits to distribute timing references in Ethernet/IP

Networks (PSNs): the Flexi Direct BTS (Timing Slave) is remotely frequency synchro-

nized by means of a proper sequence of t iming packets generated by an external source

(that is ToP Master).

The ToP Master Clock, which is responsible for the synchronization of the Flexi Direct

BTSs, is the Symmetricom’s TimeProvider5000 equipment, or alternatively SSU2000

equipped with a unit providing master clock functionality.The ToP Master Clock serving a large number of slave clocks is the most critical part of

the ToP solution. Therefore, ToP Master Clock can have fully redundant units (that is

hot standby) for ToP processing; the Flexi Direct BTS slaves see the fully redundant

master as a single master with one address.

The ToP packets, which should be treated in the transport network with the highest

priority (EF PHB), have to be forwarded between the ToP Master, located in the Core

Network (CN), and the Flexi Direct BTS with the lowest jitter.

ToP solution implementation is compliant to IEEE 1588v2 standard. It defines the Pre-

cision Time Protocol (PTP) which enables multi-vendor distributed systems (that is

network communications) with clocks of various inherent precision, resolution and sta-

bility, to synchronize to a grandmaster clock.

The following features and functions of IEEE 1588 v2 are supported for ToP solution:

• Master clock acts as timing master for the slave clocks.

• Slave clock recovers the timing based on the communication between the master

and the slave.

• Sync message carries the basic timing information from the master to the slaves.

• Unicast is the communication mode between the master and the slaves in Flexi

Direct ToP application.

• Unicast Discovery is used for configuring the slave with the address of the master.

• Unicast Negotiation is used to start unicast communication between the master and

the slaves.



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Figure 17 ToP Architecture

Figure 18 Protocol stack for ToP

8.1.8 IP Security

IPSec is a feature that enables securing the traffic sent over an IP network. In the

networks where RNCs are in separate secure core network sites there is no possibility

to eavesdrop the packet. As the Flexi Direct RNCs are moved towards Flexi Direct BTS

sites and thus exposed to security breach, the support of IPsec is essential for informa-

tion security.

In the networks where RNC is used and a secure transmission pipe is needed, theSecurity Gateway (SGW) is installed in the RNC site. In Flexi Direct network, it is not

feasible to install SGW per each Flexi Direct BTS as that would increase cost of the

network. Therefore, IPSec encryption and authentication is introduced in Flexi Direct

RNC.

IPSec is used to protect the following interfaces in Flexi Direct BTS:

• IuPS-c

• Iu-PS-u

• IuCS-c

• IuCS-u

• Iur-c

• Iur-u

Timing over Packet

Eth

Eth

Eth

Ethernet/IP

Flexi Direct BTS

Flexi Direct BTSSwitch/Router

Top Master





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8.1.9 Hybrid Transport solutions for Flexi Direct BTS

Hybrid Transport functionality is a hybrid mobile backhaul concept for enabling selective

use of E1/TDM or IP/ETH on the Iu (IuCS & IuPS) and IuR interfaces. This allows to

benefit from simultaneous use of ATM and Ethernet infrastructure. By doing so the con-gestion of each interface is decreased.

The two hybrid scenarios are presented in the Flexi Direct transport scenarios overview

table below.

The characteristics of two hybrid transport scenarios are as follows:

1. Hybrid Transport Scenario 1

The main characteristics of transport network considered in this scenario are as

follows:

•Transport network configuration uses a single virtual path (VP) per Flexi DirectBTS.

• Transport network consists of a single virtual channel connection (VCC) carrying

Iu-CS control and user plane traffic.

• Possible cross-connections in the transport network are based on VCC cross-

connections.

The ATM layer configuration between the Flexi Direct BTS and core site can be

made using VCC. The proposed VCC configuration is as follows:

• 1*VCC for user and control part traffic on all interfaces

The use of different VCCs makes it possible to configure dedicated resources for

each traffic type and enables the efficient use of the bandwidth.

With traffic separation, all traffic demands are dimensioned according to the input

traffic type mix and have dedicated VCC bandwidth to convey data between Flexi

Direct BTS and operator’s core site. Enabling the UBR+ ATM service category for

HSPA traffic allows more flexible use of the available bandwidth comparing to CBR.

2. Hybrid Transport Scenario 2

The main characteristic of Hybrid Transport Scenario 2 is the same as Hybrid Trans-

port Scenario 1.

g For more information see Hybrid Transport Solutions for Flexi Direct BTS feature

description in Transmission and Transport Feature Descriptions.

InterfaceHomogenous Homogenous Hybrid Scenario 1 Hybrid Scenario 2

IP/Ethernet IP/ATM/PDH IP/Ethernet IP/ATM/PDH IP/Ethernet IP/ATM/PDH

Iu-CS (CP&UP) X X - X - X

Iu-PS (CP&UP) X X X - X -

Iur (CP&UP) X X X - - X

Iu-PC X X X - X -

DCN X X X - X -

Table 1 Flexi Direct transport scenarios overview

http://x%3Dd%3Do%3Dc/s-000111.pdf






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8.2 QoS support on IP

For IP Transport option, the Quality of Service (QoS) at transport layer can be provided

with:

• DSCP mapping according to DiffServ architecture

• VLAN priority bits

• VLANs separation

QoS for ATM Transport option at transport layer can be provided with traffic managem-

net functions like service category, traffic shaping, buffer management, and scheduling.

DSCP mapping

The traffic classification is based on DSCP information contained in the IP packets. All

traffic sourced from the Flexi Direct BTS in uplink direction is marked with a proper

DSCP value, inserted into the type of service (Type of Service) field in IPv4 header, to

allow a proper prioritization of the packet towards external NEs. The DSCP value

assigned to each IP packet is used to map it into a Per-Hop-Behavior (PHB) in the

network according to IETF RFC2474.

The Flexi Direct BTS binds the allocated DSCP value to a PHB value according to a

table configurable by NetAct. Table 2 DSCP mapping - default values reports the default

mapping between DSCP and PHB values.

The transport scheduler sends the IP packets to the relevant queue according to the

PHB value and the weight associated with the traffic class.

Traffic Type DSCP Default values PHB

UMTS Traffic

ConversationalTCToDSCP 46 EF

StreamingTCToDSCP 34 AF4InteractiveTHP1ToDSCP 26 AF3

InteractiveTHP2ToDSCP 18 AF2

InteractiveTHP3ToDSCP 10 AF1

BackgroundToDSCP 0 BE

Signaling

Control Plane (RANAP; RNSAP) 34 AF4

GTP-U 34 AF4

Network Control Traffic

OSPF 48 EF

ICMP 0 BE

Synchronization

ToP 46 EF

Table 2 DSCP mapping - default values



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In case some traffic is encrypted with IPsec (tunnel mode), the DSCP value to consider

is that of the outer IPsec IP header. This DSCP value is copied from the header of the

inner IP packet.

Internet Control Message Protocol (ICMP) monitoring and Bidirectional Forward-ing Detection (BFD)

Flexi Direct RU30 supports BFD (CD release) and ICMP echo replying (ping reply). In

the next releases for ICMP Ping in Flexi Direct BTS, a DSCP value for the ICMP packets

will be recommended with a default value.

VLAN priority bits

In an L2 network scenario it is assumed that the traffic prioritization is based on VLAN

priority bits of Ethernet frame according to IEEE 802.1p.

The Table 3 VLAN priority bits reports the default mapping between VLAN P-bits and

PHB values.

VLAN support

According to IEEE 802.1Q, VLANcan be optionally supported in case of IP over Ethernet

interfaces.

Optionally, a mixture of Ethernet frames with and without VLAN headers are supported

with the same Ethernet interface. The priority bits in the VLAN header are supported.

VLANs can be used for:

• Control Plane and User Plane resources separation at Iu interface.

• Separation of logical interface instances of Iur and Iu: Iu-PC, Iu-BC, ToP and O&M.

• traffic classification

In Flexi Direct BTS the VLAN option can be used for traffic separation and classifi-

cation based on DSCP value. Traffic separation is performed for the different logical

interface instances. Mapping of traffic into separate VLAN ID can be used in the

transport network can be used in transport network by Service Level Agreement

(SLA) and lead to to finer traffic classification.

Traffic management via ATM virtual channel separation

A traffic contract specifies the desired ATM service category, the desired QoS, the traffic

parameters, and the associated tolerance values.

VLAN P-bits PHB default

7 ARP (not configurable)

6 EF

5 AF4

4 AF3

3 AF2

2 -

1 AF10 BE

Table 3 VLAN priority bits



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The ATM service categories "CBR", "UBR" are implemented according to the ATM

Forum specification document AF-TM-0121.000 version 4.1. The ATM service category

UBR has been extended by ATM Forum standard [Addendum to Traffic Management

v4.1 for an Optional Minimum Desired Cell Rate for UBR; AF-TM-0150; July 2000) to

support an additional parameter Minimum Desired Cell Rate (MDCR). An UBR imple-

mentation that supports the MDCR parameter (that is when MDCR value is set to more

than "0") is commonly denoted as UBR+. The UBR+ service category includes the UBR

service category as well.







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9.2 User security

Flexi Direct user security involves authentication, authorization, user event logging and

log collection, and user accounts and groups.

9.2.1 Authentication

Adapter C-plane

Authentication is based on the standard username/password pairs. Authentication

involves the following events:

• MMI sessions over telnet or SSH (MML command line)

• HTTP

• FTP

• BTS Operation and maintenance

For all the above events, authentication uses the same program block. User is

authenticated with a local username/password file, or with a NetAct LDAP server.

Adapter U-plane

In Flexi Direct, there is no authentication on the U-plane. The users are authenticated

through O&M plane.

OMS

Flexi Direct uses standard Linux username/password authentication.

Remote authentication

Flexi Direct RNC, OMS, and Flexi Direct BTS support centralized user information man-

agement, where the remote authentication server at the NetAct site authenticates users.

OMS contains its own LDAP server that is synchronized with NetAct through NWI3.

NWI3 sessions are authenticated with own username/password pair for each network

element.

If NetAct is not present in the system, remote authentication is not possible, and

therefore, the system uses local authentication.

Password requirements

Password requirements include length, complexity level, and the aging policy.

Passwords for local users follow the NET Security Hardening Guide. NetAct controls

password for the NetAct users.

9.2.2 Authorization

Authorization of local users

In Flexi Direct RNC control plane and user plane, authority requirement assigns the

MML commands, the number from 1 to 250. This is a predefined number that can be

changed during the runtime. User’s profile contains the authority level of the user. If this

authority level is not lower than the authority requirement level of a command, the user

can execute the command. The system does not differentiate between the types of file

access: user can either access to all files, or have no access at all.

In OMS, Flexi Direct uses standard Linux authorization.



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Centralized User Information Management

Centralized User Information Management defines an authorization mechanism that the

remote authentication server at the NetAct site manages. It is an optional feature and

can be present only when NetAct is present in the system.

9.2.3 User event logging and log collection

Flexi Direct System employs Centralized User Event Log Management feature that

implements support for user event log collection in the Flexi Direct RNC. It is managed

by NetAct.

g There is no support for centralized log management in the Flexi Direct BTS.



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10 Operability overview

10.1 Introduction to Flexi Direct System operabilityOperability is the ability of a system to operate. Flexi Direct System is affected by various

Network Elements (NEs) and to guarantee a faultless and undisturbed functioning,

these NEs need to be configured and managed accordingly. The NEs needed for Flexi

Direct System to operate are:

• Flexi Multiradio BTS

• Flexi Direct RNC integrated into FTLB transport module

• Flexi Direct OMS (Operation and Management Server)

Flexi Direct System offers support of centralized management by means of NetAct

Network Management System (NMS). NetAct is optional element of the network, not

required by the system to be operational. Flexi Direct Operability documentation coversaforementioned network elements’ roles related to the entire system operability. These

roles are covered in the context of “what is” rather than “how to”.

The operability functional area of Flexi Direct consists of the following subfunctionalities:

• configuration management (including topology and plan management)

• performance management

• fault management

• software management

• security management

• user management

•HW management (BTS)



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10.2 Flexi Dirext System operability architecture

Flexi Direct System has been introduced to flatten the existing HSPA (HSDPA/HSUPA)

network architecture. In this solution, packet-switched and circuit-switched functionality

of a classical RNC is moved to Flexi Multiradio Base Station and performed by the FlexiDirect RNC.

Two solutions for operating the Flexi Direct System are available: operability solution

with NetAct and without NetAct, using only OMS. However, solution with NetAct is pre-

ferred and in this case OMS acts as a mediator between Flexi Direct RNC and NetAct.

Operability solution with NetAct

NetAct is a network and service management solution that consists of many tools for

handling a number of network elements and expanding networks. It is designed to

handle an increase in both complexity of the network and amount of traffic and data. The

NetAct solution is very useful in large networks, where centralized management is

essential.NetAct offers efficient management of different network technologies with an integrated

and interworking tool. It provides the operator with a tool for controlling costs while rede-

ploying competencies and resources from 2G to 3G, HSDPA, HSUPA, and Flexi Direct.

In addition, due to its pre-integrated and process-based nature, it is possible to visualize

network element failures, service quality indicators, and the traffic flows on a screen.

These, among other characteristics, allow the operator to optimize and deliver higher

network and service quality to the end user.

Operability solution with OMS only

Network management based on OMS only is a solution recommended to the operators

of small networks. Flexi Direct OMS offers a local management interface towardsnetwork elements with basic centralized alarm and performance management capabili-

ties. Flexi Direct OMS participates as a centralizing node to all key management tasks,

such as fault, performance, configuration, topology, and software management.

Full-scale fault management, performance reporting, configuration and software

management are provided by NetAct.

The Figure 20 Flexi Direct System operability architecture pictures operability solution

for Flexi Direct System.

Even if NetAct is used for centralized management, OMS must be present as an O&M

mediator and aggregator.



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Figure 20 Flexi Direct System operability architecture

Network elements in the radio network necessary for Flexi Direct System management

are:

• Flexi Multiradio BTS for WCDMA

Flexi Direct BTS

Iub

BTSOM

WBTS

IuPS-U

Flexi

Direct

RNC

IuCS

IuPS-C

BTSOM

SGSN

OMS NetAct

3rd party NMS

Gi

MSS

NE3S

Q3

Q3

NWI3

Note: Iub is an internal interface in Flexi Direct system.

GGSN



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• Flexi Direct RNC integrated into FTLB transport module

• Flexi Direct Operation and Management Server (OMS)

• NetAct (centralized management)

Flexi Multiradio BTS with an Flexi Direct RNC functionality is an Flexi Direct enabledwideband WCDMA base station (Flexi Direct BTS). Although Flexi Direct RNC in Flexi

Direct RU30 is not a HW unit, it is visible as a separate logical entity in the network. It

means that the Flexi Direct RNC is managed as own NE in the topology from Netact or

Flexi Direct OMS (I-OMS).

OMS is a single NE used to manage higher number of Flexi Direct RNCs. However, you

can decide to use centralized management system. This possibility is provided by

NetAct.



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10.3 Flexi Direct OMS Element Manager

Flexi Direct OMS element manager (EM) is a tool for performing operational tasks in the

network element (NE) using graphical user interface (GUI) applications. EM consists of

an application launcher (AL) and EM applications that are downloaded and installedfrom the OMS located in the network element to the client computer (EM workstation).

Even if OMS is not used as an Element Manager, it is required as a O&M mediator and

aggregator.

The application launcher is used for downloading other EM applications, for example

parameter tool, from the network element and for launching these applications. The AL

runs on the Java virtual machine (JVM) on the client side, as shown in the EM architec-

ture Figure 21 Flexi Direct OMS Element Manager architecture. Parameter tool is used

for managing the parameters stored in the OMS internal LDAP database.

The following figure presents the Flexi Direct OMS EM architecture:

Figure 21 Flexi Direct OMS Element Manager architecture

The AL and other EM graphical user interface software is delivered as part of the Flexi

Direct OMS software package. AL is the only EM application that has to be installed to

the client PC. The AL client installation is started from the EM workstation using a web

browser. The AL then downloads the other EM applications to the client workstation from

the Flexi Direct OMS, using HyperText Transfer Protocol (HTTP) over Secure Sockets

Layer (SSL), also called HTTPS protocol.

The following protocols are in use:

•HTTPS for downloading EM software from the web server in the NE and for loggingto the NE using AL

• Internet Inter-ORB Protocol (IIOP) for using CORBA services (for example NWI3

adapter services)

• LDAPS for communicating with the LDAP Directory

Web browser

ApplicationLauncher /

Parameter Tool

EMGUIs

JVM

Client

HTTPS

IIOP

(CORBA)

JVM

Web Server

LDAP Server

CO

RB

A

ser ve

r

OMS

LDAPS

Platypus

Element Manager



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10.4 Autoconnection

Autoconnection is a feature which enables the automated connection of the new or

uncommissioned Flexi Multiradio BTS WCDMA to a server in the network through which

commissioning may be automatically performed. The benefit for the operator is costeffective and quick network rollout.

Autoconnection in Flexi Direct works as follows. A newly installed Flexi Direct BTS auto-

matically retrieves its IP Address via DHCP and establishes IP connectivity with the Flexi

Direct OMS. The operator uses the information logged in OMS in order to establish Site

Manager connectivity with the Flexi Direct BTS and remotely commissions the BTS,

without the need for a site visit by the commissioning engineer.

For more information on autoconnection mode in Flexi Direct, see Enable autoconnec-

tion in Commissioning Flexi Direct BTS.

http://ibts_commissioning.pdf/








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10.5 Remote Commissioning

In Flexi Direct System RU30, it is possible to convert Flexi Multiradio BTS to Flexi Direct

BTS through remote commissioning.

BTS to Flexi Direct BTS mode switching is done with BTS O&M interface using the exist-

ing, active M-Plane transport network connectivity. BTS Commissioning is performed by

executing a script file that is responsible for downloading and commissioning Flexi

Direct RNC software and configuring the IP addresses. This procedure is executed on

the Octeon processor of the FTLB transport module (additional processor for Flexi

Direct RNC functionality).

High level flow of events during the BTS to Flexi Direct BTS switching is shown in Figure

22 Flexi Multiradio BTS reconfiguration to Flexi Direct-BTS functionality.

Figure 22 Flexi Multiradio BTS reconfiguration to Flexi Direct-BTS functionality



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For more information on commissioning procedures, see Commissioning Flexi Multira-

dio BTS document.

http://com_flexi_wbts.pdf/






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10.6 Configuration management

Configuration management is a set of functions used to configure network elements and

other entities in the radio network.

In Flexi Direct System, configuration management is performed with the use of NetAct

and/or OMS. OMS provides a log where user-originated operations can be viewed.

10.6.1 Topology management in Flexi Direct System

Topology management enables to view and manage the network topology of the Flexi

Direct system. Topology means the hierarchy of connections between the functional and

logical objects.

Primary work flow

The primary work flow of topology management is handled through NetAct. It means

managing the hierarchy of connections between the network elements (NEs) connectedto NetAct. These NEs with their functional elements are stored in the NetAct Topology

Database. They can be viewed with the CM Editor application, accessible from Config-

urator.

CM editor enables to:

• display the whole network stored in the NetAct database or user-defined network

sections in form of a list.

• search for NEs of your choice.

• view managed network object details.

• create new objects and delete existing ones.

• mass-edit the parameters.

Secondary work flow

If needed, topology management can be performed through OMS. OMS provides con-

venient topology management of the Flexi Direct network elements that are hierarchi-

cally underneath. Topology management is performed through topology browser.

Topology browser is a web-based application that enables browsing the structure of the

network topology directly from the OMS database called the master data repository. You

can also see topology changes and state changes in nearly real time. Furthermore, you

can see the relationships of managed objects and attributes along with their values for

a selected item. Also various table views of topology objects and ongoing O&M opera-

tions are available. You are able to execute privileged O&M operations for the managed

Flexi Direct RNCs and Flexi Multiradio BTSs and objects. Topology browser allows to:

• delete Flexi Direct RNC from topology tree.

• request reset for Flexi Direct RNC.

• lock or unlock WCEL.

• view ongoing and completed configuration management operations.

After logging in to web based user interface, there are two ways of browsing and

managing network topology with topology browser. These are: tree view and list view.

Tree view of a Flexi Direct topology run in topology browser is pictured in the following

figure.



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Figure 23 Flexi Direct topology tree view screen capture

g Note that OMS is labeling the Flexi Direct topology as in the GUI as “I-HSPA topology”.

The tree view enables browsing the network and parameters (such as IP address,

network ID, software version) within a view that reflects actual network topology. This

view provides easy access to elements structured underneath a given element (child

objects) and to their parameters.

Topology list view enables browsing the network elements which are specified in a list.

Using the list view you have also access to objects’ parameters.

You can perform every topology browser operation from either tree view or list view.

10.6.2 Plan management in Flexi Direct System

Plan management downloads and uploads plan files to network elements in a coherent

way. Plan files consist of a set of parameter values needed to configure a given network

element or network element type.

Plan management is needed for making possible changes on system level. There are

several types of plans: Radio Network Plan (RNW), FTM Plan, IP Plan, and Signaling

Plan.

Primary workflow

The primary work flow of plan management is handled through NetAct. Plan manage-

ment is performed with CM Operations Manager, CM Editor, CM Analyzer, and Plan

Editor. The first three applications are accessible from Configurator. The characteristics

of those applications is as follows:

• Plan Editor

Plan Editor is intended for offline data modification, not directly for implementation

to the network. The implementation to the network is done with network manage-

ment systems, such as NetAct, after the parameter data is imported into the NetAct

databases.



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• CM Operations Manager

If a larger set of parameters is modified as part of the configuration management

process, a plan must be implemented. This functionality is provided by CM Opera-

tions Manager. CM Operations Manager makes it possible to implement planned

configurations in the network. The operations can be performed immediately or

scheduled for a specified time. When plans are activated, the plan values are taken

into use in the network. CM Operations Manager has the following functionalities:

– Plan Import

Radio network plans can be transferred from the planning applications to Con-

figurator; once the plan is in the NetAct database, it can be modified and

prepared for pre-activation or activation in the network.

– Plan Export

With which it is possible to transfer planned configurations to an external tool.

– pre-activation and activation of the plan

Plans are created or modified using an external application (for example Planner,

Plan Editor) as a.csv or.xml file. Then, they are imported to configurator‘s database.

Only after importing the plans to Configurator, it is possible to activate them in an

NE.

• CM Editor

CM Editor is an application for editing and creating radio network and core network

plans and templates and for directly modifying the actual ones in the network. CM

Editor is generally used for creating plans, while CM Operations Manager's role is

to implement the plans to the network. However, CM Editor also allows online

parameter modifications. CM editor is a tool that:

– gives an online access plans and parameters on-line in the database.

– supports all radio network parameters and objects.

– modifies parameter values and object data, creates new objects, and deletes the

existing ones.

– provides parameter mass editing, that enables effective modification of a

number of managed objects.

– supports configuration of a parameter view to contain only the information that

is relevant for the current tasks.

– enables fast plan creation and systematic plan management by making it

possible to use previously defined and tested parameter settings for setting up

new sites.

• CM Analyzer

CM Analyzer enables checking of radio network parameters and managed objects.

It also ensures that the parameters and plans are defined according to consistency

rules and no essential information is missing. You can check for discrepancies both

in actual configuration and in planned configurations. When checking planned con-

figurations, the operational network parameters are taken into account, as needed,

to reflect the situation that would exist in the network after downloading the plan.

Secondary workflow

If needed, plan management can be handled through OMS. The plan management

application in OMS enables deploying different kinds of plan files to the NEs. The plans

can be created with NetAct Plan Editor application. However, if plan management is

handled through OMS, it is OMS that delivers plan files to network elements. OMS can

distribute multiple plans and activate plans carrying out parallel mass operations.





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10.7 Performance management

Performance management functionality consists of processing, storing, and

administering of performance-related statistical data. This is required before it can be

further used by various network and service management applications. The featureincludes the following:

• performance data management

• measurement administration

• threshold monitoring

• data transfer reliability assurance

The aim of any performance management activity is to collect data to support the

following activities:

• verifying the physical and logical configuration of the telecommunications network

• continuously monitoring how the network functions

• localizing potential problems as early as possible

• monitoring subscriber behavior

• providing optimum services to mobile subscribers

Depending on how the performance management applications use the collected data,

they can be divided into two main types: performance monitoring and performance

reporting applications.

10.7.1 Performance management in Flexi Direct System

Primary workflow

The primary work flow of performance management is handled through NetActReporter. This tool is a group of applications for monitoring and reporting. The Flexi

Direct Network Elements send measurement data to NetAct PM database. These data

is then visualized in the NetAct reporting applications and distributed to end users.

Reporting applications available both on global and regional level are:

• Report Browser

• KPI Browser

• Report Builder

They allow:

• create adequate reports for each group within the operator organization.

• create own report sets.

• evaluate the reliability of the generated reports.

• design advanced web interfaces for filtering, highlighting and visualizing all kinds of

data.

For more information, see Reporter and Performance Management Principles in NetAct

product documentation.

OMS role

If needed, performance management can be handled through OMS. OMS provides the

following performance management functionalities:

•RNW Measurement management GUI for the management of the followingmeasurements:





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10.8 Fault management

Fault management means employing a set of functions with which a fault situation in a

system is detected and corrected. Fault management is a process consisting of several

steps. First, the fault is detected. Next step is on-line diagnosis, which determines thecause of the fault. After the online diagnosis, the fault is isolated. Next step of the

process is the recovery of the system and, if needed, off-line diagnosis of the fault. Only

then the faulty parts of the system can be replaced with the working ones. This replace-

ment repairs the system.

10.8.1 Fault Management Architecture

In Flexi Direct System, fault management allows monitoring the faults. Faults are indi-

cated to the user as alarm notifications that have a certain basic characteristics in each

network element for identifying and correcting the fault. Each network element keeps

track of its own alarm situation and provides interfaces for viewing the alarms or

managing the network element alarm system. These interfaces are provided both to

local users and to NetAct through local user interfaces.



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Figure 24 Fault management functionality architecture in Flexi Direct System

10.8.2 Fault management in Flexi Direct System

Primary workflow

The primary workflow of fault management is handled through NetAct Alarm Monitor.

This application is a part of the NetAct Monitor functionality. The Alarm Monitor presents

the active alarm status on the network in the form of a list. This list is updated

automatically at a time interval which can be set by the user. The user has different

viewing choices, either all the alarms can be seen in the same pane or each alarm is

shown in an alarm-class-specific pane. The Alarm Monitor is also equipped with the

NetAct

Alarmmonitor

FMGUI

WCDMA BTSFlexi DirectRNC

Flexi Direct OMS

NWI3 interface

BTSOM interface

BTSOM

interface

Flexi Direct BTS



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Audible Alarm function that generates a sound when an alarm belonging to a certain

alarm class arrives.

For more information on the fault management system in NetAct, see the Monitoring

Principles in NetAct product documentation.

Secondary work flow

Although main purpose of the OMS alarm system is to act as a mediator between

network elements and NetAct fault management can be handled only through OMS.

Fault management is then performed with OMS fault management GUI.

Fault management allows executing alarm system administration operations such as:

• viewing and canceling active alarms

The view can be filtered with rules, such as alarm number, and/or object.

• uploading alarms

• managing alarm indication preventions

Alarm indication can be prevented so that alarm is not sent to NetAct.

• managing alarm parameters

• viewing alarm history

Alarm history can be filtered with object, alarm number or time interval; graphical

presentation of alarm history is also available.

• reducing alarm flow with History Analysis Graph

As a part of the Flexi Direct alarm system, the OMS alarm system manages and stores

Flexi Direct alarms and makes them available for NetAct and Element Manager's fault

management application (FM GUI). The OMS alarm system also processes and stores

the alarms raised in the OMS itself.



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10.9 Software management

Software management takes care of the software in the network elements in a controlled

way. SW management consists of a set of functions that provide strictly controlled

means for manipulating the software in NE. It also allows scalable updating of SW fromthe level of one individual software component up to the entire software build of the SW

system running in NE. With the help of SW management, the needed changes to the

SW of the network element can be made systematically while maintaining the integrity

and traceability of the SW configuration throughout the NE software release life cycle on

field.

Common SW management features are:

• SW download to NE

• SW upgrade and activation in NE

• NE SW configuration upload

•NE SW backup

10.9.1 Software management in Flexi Direct System

Primary workflow

The primary workflow of software management is handled through NetAct. It is per-

formed with Software Manager application accessible from Administration folder in the

NetAct GUI.

Software Manager allows remote management of software configurations in network

elements. It allows uploading the software configuration information from NE to NetAct,

importing the NE software from NE to NetAct, importing NE SW and activating the NE

SW. You can easily search and examine software configuration data from a remote loca-tion. The system saves the software configuration information in the NetAct database

that you can update regularly. An important feature of this application is also that you

can save the software to the NetAct disk and download to the managed objects from a

remote location. The task status can be also viewed.

With the Software Manager application, you can perform the following:

• view the SW status

• view software configurations in network elements

• upload software configuration information from NE to NetAct

• download NE SW from NetAct to NE

• import NE SW to NetAct • activate NE SW in NE

• create new tasks based on:

– any available information about NEs - using Network SW Status view

– any available information related to existing tasks - using Tasks view

– predefined NE set

• schedule tasks

• modify, cancel and delete tasks

• manage SW packages in centralized SW archive

For more information, see Software Manager Help in NetAct product documentation.



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Secondary workflow

If needed, the software management application in OMS can be used. Software man-

agement enables delivering software packages to multiple NEs and performing optional

software package activation after the download.Software management has the following operations:

• download and activate software to Flexi Direct RNC and WCDMA BTSs

• view software operations

• inquiry of software version

With the software management application you are able to download software to NEs of

your choice (ones selected in the application). This download is performed directly from

the client computer to OMS and then the OMS delivers the package to the selected NEs

(Flexi Direct RNCs or WCDMA BTSs) where it is then activated.




10.10 User management

User management means administering user accounts in the system.

Users are authorized to establish sessions and to execute commands in the system,

depending on their authorization level. User accounts can further be divided into differ-

ent user groups according to their operating tasks and expertise. It is possible for the

same user account to be part of several user groups.

Primary workflow

The primary workflow of user management is handled through NetAct. For more infor-

mation about administering user accounts in Flexi Direct System with NetAct, see

System Administration Principles in NetAct product documentation.

Secondary workflow

If needed, user management can be handled through OMS. The user interface to

manage the user accounts and user groups is command line interface (CLI).With respect to user management, the CLI can:

• create new user accounts and user groups.

• assign privileges to user accounts and user groups.

• modify privileges of existing user accounts and user groups.

• delete existing user accounts and user groups.

With the exception of Linux system accounts and two fallback accounts _nokfsoperator

and _nokfssysemoperatorfallback that are stored in the operating system, all user

accounts (for humans) and service accounts (for process-to-process communication)

are stored in the LDAP server. As a consequence, each user is assigned only a single

username and password, no matter how the user is accessing the services or where theuser account information is stored. Shared user accounts are not permitted, since it is

difficult to trace the actions if users are allowed to log in using shared accounts.

Documents

Flexi Direct System Description