introduction to the volte solution

Introduction to the

www.huawei.com

Introduction to the VoLTE Solution

Copyright © 2014 Huawei Technologies Co., Ltd. All rights reserved.

Reference

� VoLTE Product Documentation

Copyright © 2014 Huawei Technologies Co., Ltd. All rights reserved. Page1

Objectives

� Upon completion of this course, you will be able to

understand:understand:

� VoLTE solution basic concepts

� VoLTE solution architecture

� VoLTE evolution trend

Huawei VoLTE solution products and deployment principles


� Huawei VoLTE solution products and deployment principles

Page2

Contents

1. VoLTE Solution Basic Concepts

2. VoLTE Network Evolution2. VoLTE Network Evolution

3. Huawei VoLTE Solution Architecture

4. Huawei VoLTE Solution Products


Contents


1.1 Commercial LTE Voice Solutions1.1 Commercial LTE Voice Solutions

1.2 Advantages of VoLTE

1.3 Key Technologies Involved in VoLTE


Commercial LTE Voice Solutions


CSFB Definition� The circuit switched fallback (CSFB) service enables calls to fall back to the CS

domain. The LTE network provides only data services. When a voice call is initiated or answered, it falls back to the CS domain for processing. Therefore, carriers only need to upgrade the MSC server without deploying the IMS network.carriers only need to upgrade the MSC server without deploying the IMS network.

� Advantage: Voice services can be provided quickly with little change on the live network.

� Disadvantage: When subscribers use voice services, data services carried on the LTE network are interrupted, handed over, or suspended, and voice calls are connected slowly. This affects user experience.

� Application scenario:

CSFB is a transition solution before the IMS network deployment.


� CSFB is a transition solution before the IMS network deployment.

� If the IMS network is not deployed on the visited network, CSFB can provide voice services for roaming LTE subscribers.

Page6

CSFB Definition (Cont.)

MME

SGs

MSC server

CS EPC

� Terminating side� The MSC server sends a paging request to

the MME over the SGs interface.� The MME forwards the paging request

instructing the UE to fall back to the 2G or 3G network.

� Originating side

The UE sends a voice call request to the

LTE2G/3G

MMEMSC server

CS EPC

Fallback

3

SGs

1

3G network.� The UE falls back to the 2G or 3G network.� The UE sends a paging response to the

MSC server and answers the call based on the normal terminating flow.

1

2

� The UE sends a voice call request to the

MME. The MME then instructs the UE to

fall back to the 2G or 3G network.

� The UE falls back to the 2G or 3G network.

� The UE initiates a call based on the normal

originating flow on the 2G or 3G network.

LTE2G/3G

4 2

Fallback3

Page7

SVLTE Definition� In the simultaneous voice and LTE (SVLTE) solution, dual-mode mobile phones

work on the LTE network and the CS network simultaneously. The LTE network provides data services, while the CS network provides voice services.

� Advantage: SVLTE is a solution for mobile phones without requirements for the network.network.

� Disadvantage: The cost and power consumption of dual-mode mobile phones are high.

CS EPC

MSC serverMME


LTE2G/3G

Data serviceVoice service

Page8

OTT Definition

� Over-the-top (OTT) is a solution that uses APPs, such as the Skype, to

provide voice services for LTE subscribers.

� Advantage:

� Only the OTT server needs to be deployed to the live network and slight change is

required. The OTT can enhance user experience by offering rich multimedia

services.

� Disadvantages:

� The OTT solution is not carrier-class-based and has low reliability.


� The OTT solution cannot provide E2E QoS guarantee.

� The OTT solution is hard to provide common services, such as emergency calls

and interception, and services that are used only by regulatory bodies.

� Roaming and interconnection are hard to be implemented due to lack of standards.

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Contents






VoLTE DefinitionVoice over long term evolution (VoLTE) is an IMS-ba sed voice solution defined by 3GPP. By deploying the IMS network, operators no t only migrate traditional voice and short message services on live networks b ut also integrate voice services with various enhanced functions to diversi fy services.

VoLTE advantages

� The VoLTE solution inherits all services provided by the CS network, including common services, such as emergency calls and interception, and services that are used only by regulatory bodies.

� The VoLTE solution can implement E2E QoS control and guarantee voice call quality.

� In the VoLTE solution, voice services are carried on IP networks. Therefore, subscribers can enjoy richer multimedia services through the IMS network, compete with OTT.


enjoy richer multimedia services through the IMS network, compete with OTT.

� Subscriber identities (such as the MSISDN) are reserved, which maximizes carriers' resource usage and facilitates service profit gain.

� The IMS architecture, supported by mature 3GPP standards and specifications, is considered to be the next generation core network by the communications industry. The IMS architecture ensures roaming services and network interworking.

Page11

Advantage of VoLTE – Better and Faster

Faster connection rate

Better communication

quality

Higher spectral

efficiency

Richer services

� VoLTE can significantly reduce the call establish de lay, provide high-

� Fast connection:

� CS call establish duration is around 4-5s，

VoLTE is 0.8 -1.5s.

� HD video:

� VoLTE typical video definition is 480*640

definition audio and video calls, greatly enhance t he user experience


SD and HD video size compare

� VoLTE typical video definition is 480*640

（VGA）, HD 720P and full HD 1080P is

possible（H.264/H.265）

� 3G typical video definition is 176*144

（QCIF）

Advantage of VoLTE -- HD Voice Quality

Common ear listening range (CD/MP3 range)

The frequency range of human speechHD voice (AMR-WB)

20 Hz

20k Hz50 Hz

80 Hz

12k Hz7000 Hz

HD voice (AMR-WB)

300Hz

3400Hz

CS（AMR-NB)

Audio range


HD voice: (Twice frequency range the AMR-NB)

• VoCS voice: AMR-NB 300~3400 Hz, sampling frequency 8kHz, 12.2Kbps。• VoLTE HD voice: AMR-WB (G.722.2 ) : 50~7000 Hz, same as the G.711 in PSTN, sampling frequency 16kHz, 23.85Kbps. • CD music: 20~20K Hz, sampling frequency 44.1K.

Advantage of VoLTE -- QoS

Best effort for OTT services

Dedicate bearer for VoLTE

LTE


QCI Resource Pri. Delay Error rate service

2 GBR 4 150ms 10 -6 VoLTE video

6 Non-GBR 6 300ms 10-3 OTT video

QCI: QoS class identifier GBR: guaranteed bit rate

Comparison Among CSFB, SVLTE, VoLTE and OTT

Solution Feature Advantage DisadvantageDeployment Suggestion

VoLTE

The IMS and LTE networks provide voice services. The handover between the LTE

Rich multimedia services.HD voice/video.

The IMS network needs to be deployed.

Large-scale LTE coveragebetween the LTE

network and 2G/3G network is supported.

HD voice/video.E2E QoS

needs to be deployed. coverage

OTTVoice services are implemented by APPs of OTT carriers.

Slight change is required on live networks.

Voice calls are not reliable.Roaming and interworking are hard to be implemented.

-

CSFB

UEs attach to the LTE network. When a UE initiates or receives a call, the UE falls back to

Slight change is required on live networks.New NEs do not need

The call delay is long.User experience is affected.

Initial phase of the LTE network (transition


call, the UE falls back to the CS network.

New NEs do not need to be deployed.

affected.(transition solution)

SVLTE

Terminals attach to both the CS and LTE networks. The CS network provides voice services.

The live network does not need to be adjusted.

Costs of mobile phones are high. Advantages of the LTE network cannot be used.

Initial phase of the LTE network (transition solution)

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Contents






Key Technologies Involved in VoLTE

� Voice based on IMS

� VoLTE voice services are IMS-based.� VoLTE voice services are IMS-based.

� SRVCC/eSRVCC

� If VoLTE voice services need to be handed over the GSM or

RAN network, SRVCC or eSRVCC is used.

� ICS for VoLTE


� ICS for VoLTE

� To ensure that subscribers have consistent user experiences

on the LTE and CS networks, ICS is used.

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IMS-based Voice Services

� A default bearer is set up for IMS signaling streams when the UE attaches to the network.

� After the UE initiates a call, SIP signaling streams for call connection is transmitted over the

default bearer through the P-GW to the IMS Core.


default bearer through the P-GW to the IMS Core.

� A dedicated bearer for IMS voice media streams is set up during call connection.

� Voice media streams of the calling and called parties are transmitted over the dedicated bearer.

� The PCRF assigns and delivers QoS rules for signaling and media streams during the setup of

default and dedicated bearers. This ensures quality of signaling and media streams.

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SRVCC Definition

� Single radio voice call continuity (SRVCC) is an IMS-based VoLTE.

� VCC describes how a voice call can be continued when a UE moves

between the target CS domain and the LTE domain supporting VoIP

services.

� SRVCC describes how a voice call can be continued when a Single

Radio UE moves between LTE/Pre-LTE and 2G/3G networks, that is,

when a Single Radio UE switches an call session between IMS/LTE and

CS.


SRVCC Definition (Cont.)� Calls are set up in the LTE over VoIP / VoIMS.

� When a subscriber moves to an area uncovered by the LTE network while holding

a call, the call is switched to the CS domain. SRVCC interprets a switchover

process.

� SRVCC solution: The media

handover point is a peer

device. Such as a peer UE.

� E2E signaling and bearer are

re-established.


� The IMS network sends the

updated media information to

the remote network, and a

session is interrupted around

1s.

eSRVCC Definition� Target: The handover delay is less than 300 ms

� Policy: The remote session update process is optimized. The media handover point is near to the local side .

Method: Media and signaling � Method: Media and signaling planes are anchored at the ATCF or ATGW to avoid the IMS session transfer process. When an eSRVCC handover is performed, only the bearer between the UE and the ATGW needs to be set up.


� The original bearer is reused to transmit media streams between the peer device and the ATGW.

Page21

eSRVCC Vs SRVCCbefore

afterSRVCC

E2E media re-establish

LTE RANIMS/SBC

eSRVCCLocal media establish

LTE RAN

IMS/SBC

（ATCF & RAN

G/U RAN

IMS/SBC

> 1.5s

Remote side

RAN

G/U RAN

（ATCF & ATGW）

~ 0s

Remote side

< 230ms


First eSRVCC testing (Vienna 201210)

1.5s 0s 230ms

LTE to GSM HO time ~ 230ms (Beijing 201404)

ICS Definition

� IMS centralized services (ICS) describe how services of subscribers who access the CS domain or IP-CAN using different terminals are managed on the IMS network in centralized mode.on the IMS network in centralized mode.

� With the ICS feature, all services are centralized to IMS. Therefore, subscribers can have consistent user experiences on the LTE and CS networks.

� By deploying an MSC server that supports the ICS feature on a network, ICS subscribers can use services provided by IMS during the initial phase of LTE in the following scenarios:


� CS subscribers who have subscribed to the ICS feature wish to use IMS services without changing their numbers.

� VoLTE subscribers who roam to or experience an SRVCC handover to a CS network wish to continue to use the IMS services.

Page23

ICS Definition (Cont.)� The ICS solution becomes the

best choice for evolution from the mobile softswitch to IMS. The eMSC server functions as

ASAS ASService layer

Centralized service

ICS Architecture

The eMSC server functions as a SIP UA and connects subscribers to the IMS Core.

� MSC server enhancements for ICS, the MSC server that supports the ICS feature, is called mobile access gateway control function (mAGCF). In

IMS Core

MGW

mAGCFMSC server

Centralized service trigger point

Access layer

xPON and FBB


control function (mAGCF). In this document, the MSC server enhancements for ICS is called eMSC server.

MGW

LTE2G/3G

LTE subscriberCS subscriber

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Contents






Contents


3.1 VoLTE Layered Network Architecture 3.1 VoLTE Layered Network Architecture

3.2 VoLTE Key NE Functions

3.3 VoLTE Interface and Protocol


VoLTE Network Architecture

Operation Support Layer and Service Layer

Operation support layer

� Operation support layer� Functions: This layer provides various

functions, such as network management, subscription data storage, unified operations on subscription data storage, unified operations on the web portal, charging, and equipment management.

� NEs: DMS, SPG, CCF, and EMS

Service layer� Service layer� Functions: This layer consists of different

application servers and resource servers to ATS


application servers and resource servers to provide services, such as instant messaging, conferences, games, as well as service capabilities, such as group and media resource capabilities.

� NEs: ATS and RCS

ATS(MMtel AS/SCC AS/IP-SM-GW/IM-SSF/Anchor AS)

Page28

Core Layer

Core layer� The core layer is divided into the following

three parts:� IMS domain: NEs in the IMS domain

implement such functions for LTE subscribers implement such functions for LTE subscribers as registration, authentication, session path control, service trigger, route selection, resource control, inter-domain interworking, and access resource control.

� CS domain: NEs in the CS domain implement

such functions for LTE subscribers as mobility management and voice services, including handovers and CSFB.

� SingleSDB: The SingleSDB provides the


� SingleSDB: The SingleSDB provides the

functions of the USCDB, HLR, IMS-HSS, SAE-HSS, PCRF, DNS/ENUM for centralized storage of VoLTE subscribers' service data. The data can be used by the CS, IMS, and EPC domains.

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Access Layer

Access layer� Access layer� Functions:� The access layer controls LTE subscriber

access and provides mobility management for

LTE subscribers.

� When an LTE subscriber is in the LTE

coverage, the subscriber can access an IMS

network through the EPC.

� When a subscriber moves out of the LTE

coverage, the subscriber can access an IMS

network through a 2G/3G network using ICS.


� If the 2G/3G network does not support ICS, a

subscriber accesses a legacy CS network.

� NEs: eMSC server (mAGCF), S-GW, P-GW, and

MME

Page30

Terminal Layer

Terminal layer� Terminal layer� LTE terminals are classified into VoLTE

terminals and non-VoLTE terminals.� VoLTE terminals are those that rely on an

IMS or LTE network to use voice services.

They include Single Radio terminals, LTE

data cards, and CPEs.

� Non-VoLTE terminals are those that rely on

a CS network to use voice services and that

connect to an LTE network to use data

services. They include Dual Radio and


CSFB terminals.

� Types: Single Radio terminals (SRVCC

terminals), LTE data cards, CPEs, Dual Radio

terminals (SVLTE terminals), and CSFB

terminals

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Contents



3.2 VoLTE Key NE Functions



NEs at the Operation Support LayerNE Name Function

SPGProvides a unified service provisioning interface and the web portal and sends the service provisioning commands received from the SPG and sends the service provisioning commands received from the BSS to the HSS, ENUM, and AS.

CCFCollects ACR messages from IMS charging NEs, such as the CSCF, ATS, and MGCF, processes the ARC messages to generate CDRs, and sends the CDRs to a BC specified by carriers.

EMS Interworks with the BSS to manage NEs in a centralized manner.


EMS Interworks with the BSS to manage NEs in a centralized manner.

Page33

NEs at the Service LayerNE Name Function

� MMTel AS: provides basic and supplementary multimedia telephony services.

� SCC AS: interworks with the SRVCC IWF and ATCF/ATGW to provide the eSRVCC function, and provides the T-ADS function

Common telephony application server (ATS)

provide the eSRVCC function, and provides the T-ADS function to select a domain for the called party.

� IP-SM-GW: provides short message interworking between IMS and CS domains.

� IM-SSF: triggers IN services in the CS domain based on the subscription information provided by the S-CSCF and the local configuration on the IM-SSF.

• Anchor AS: Routes VoLTE subscribers' calls to the IMS domain to trigger convergent services by IN-based number redirection of the anchor AS, when the VoLTE subscribers


redirection of the anchor AS, when the VoLTE subscribers originate or receive a call in the CS domain.

RCS AS

Provides the Open Mobile Alliance Instant Message (OMA IM), Presence, XML document management server (XDMS), and data synchronization (DS) functions to implement the IM, Presence, and Network Address Book services.

Page34

NEs at the Service Layer - ATS

� The ATS provides

traditional mobile services

and multimedia services.

Business service

Mobile special service

TISPAN PSTN service

3GPP MMTel service

and multimedia services.

IMS network

Mobile terminal

Soft phone

SIP terminalCPE

MBB FBB PSTN

ATS(MMTel + SCC AS + IP-SM-GW

+ IM-SSF + anchor AS)


terminal phone terminalCPE

POTS POTS

� The ATS integrates the functions of the MMTel AS, IM-SSF, SCC AS, Anchor AS, and IP-SM-GW to reduce the number of attempts to trigger iFC during calls and realize service resources sharing.

Page35

NEs at the Service Layer - SCC AS (ATS)

� The service centralization and continuity application server (SCC AS) implements handovers in the IMS domain and updates the media information about the

ISC

SCC AS

domain and updates the media information about the remote UE. In details, the SCC AS does the following:

EPCCS

IMS Core

eMSC server(SRVCC IWF)

LTE

SCC ASCalling

Called connection 3

Media connection 1Call signaling anchor point

� Analyzes information required by a handover.

� Associates handover requests and anchors sessions.

� Implements handovers


GERANUMTS

Called party access

SCC ASCalling

connection 1

Calling connection 2

Called connection 3

Media connection 2

Handover� Implements handovers between the LTE network and the UMTS network.

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NEs at the Service Layer - T-ADS (SCC AS)� T-ADS

� As defined in 3GPP specifications, domain selection by the network is

implemented by the terminating access domain selection (T-ADS).

� The T-ADS function is integrated with the SCC AS. The SCC AS queries the

convergent HLR/HSS for the UE type and access domain information and

implements domain selection based on the carrier policies. Based on the T-

ADS information, the SCC AS determines whether the current call is routed to

the IMS or CS network.


NEs at the Service Layer - IP-SM-GW (ATS)� The IP short message gateway (IP-SM-

GW) provides short message interworking between IMS and CS

OCS CGF/CDF

Ro Rfinterworking between IMS and CS domains.

IMS Core

ISC

IP-SM-GW

UE

HSS•SMS-GMSC/•SMS-IWMSC

SMSC

SME

Ro Rf

Sh

E/Gd

1 SIP message

2 Translates instant messages to short messages.

3 Sends short messages to UEs.


UESME

� After the UE sends a SIP message, the IP-SM-GW converts the instant message (SIP message) to a text message. When the UE registers with IMS, the IP-SM-GW downloads the SMSC address to a local directory.

Page38

NEs at the Service Layer - Anchor AS (ATS)

The anchor AS anchors calls from the

CS network to the IMS network as

follows:IMS

Anchor AS

AS

follows:

� Routes VoLTE subscribers' calls to

the IMS domain to trigger convergent

services by IN-based number

redirection of the anchor AS, when

the VoLTE subscribers originate or

receive a call in the CS domain.


CS MSC server

IMSAnchor AS

VoLTE subscriber



the IMS domain by IN-based number

redirection of the anchor AS, when

the VoLTE subscribers receive calls

from CS subscribers.

CS MSC server

LTE

VoLTE subscriber

Page39

NEs at the Core LayerNE Name Function

IMS-HSS (FE)

Controls subscriber roaming and stores the following information about a subscriber in the IMS network: subscriber IDs, authentication data, service data, access parameters, service trigger information, and roaming information.

Stores service-related data of subscribers, manages subscription information and SAE-HSS/HLR (FE)

Stores service-related data of subscribers, manages subscription information and location information, and combines the following NEs:• HSS in the EPC network• HLR in CS and PS domains in the core network of the mobile telecommunication

system

USCDB (BE)

Stores subscriber data and implements the functions of adding, deleting, updating, and querying data at the request of the FE.

DNS/ENUM Implements functions provided by the DNS and the ENUM server.

eMSCserver(SRVCC

Combines the following NEs:• SRVCC IWF: provides eSRVCC to ensure call continuity when terminals move

from an LTE network to a 2G/3G network.


(SRVCC IWF/CSFB proxy)

from an LTE network to a 2G/3G network.• CSFB proxy: moves LTE subscribers to a CS domain to provide voice services for

them.

MGCF

Realizes interworking between an IMS network and a PSTN or PLMN network.If fixed network optimization is required or the live network provides a lot of fixed network services, the UGC3200 is used as the MGCF. In other scenarios, the MSOFTX3000 is used as the MGCF.

Page40

NEs at the Core Layer (Cont.)NE Name Function

MRFPProvides resources for announcement playing and digit collection, voice conferences, SD video conferences.

Combines the following NEs to provide call control, service triggering, and routing functions:

I-CSCF/S-CSCF/BGCF/MRFC

functions:• I-CSCF: As the entrance to the IMS home network, the I-CSCF assigns or queries

the HSS to select an appropriate S-CSCF to serve subscribers.• S-CSCF: The S-CSCF is located on the home network as the central IMS node. It

implements subscription, authentication, session, routes, and service triggering.• BGCF: The BGCF is located on the home network to select an MGCF for calls

between an IMS network and a PSTN or PLMN network. It is integrated into the S-CSCF to reduce the need for standalone BGCFs. Therefore, call connection delay is shorten and the reliability is enhanced.

• MRFC: The MRFC controls the MRFP to play announcements and collect digits, and provide resources for voice conferences and SD video conferences.


and provide resources for voice conferences and SD video conferences.

Page41

NEs at the Core Layer (Cont.)NE Name Function

• P-CSCF: located on the visited network as the first contact point for subscribers within an IMS domain. The P-CSCF forwards SIP signaling between SIP subscribers and their home networks.

P-CSCF/SBC/ATCF/ATGW

between SIP subscribers and their home networks.• SBC: provides the core border gateway function (C-BGF) and interconnection

border gateway function (I-BGF). The C-BGF is deployed at the edge of an access network to provide attack protection and NAT traversal. The I-BGF provides media channels for an IMS network to interwork with other networks that use SIP or H.323 signaling.

• ATCF/ATGW: located between the P-CSCF and I-CSCF/S-CSCF and interworks with the SCC AS to provide eSRVCC.

MGW/IM-MGWProvides audio media channels for interworking between an IMS network and a PSTN or PLMN network.


PSTN or PLMN network.

Page42

NEs at the Core Layer - SRVCC IWF

SCC AS

� The SRVCC IWF ensures call continuity when terminals move from an LTE network to a 2G/3G network. When receiving the location update request from a UE, the SRVCC IWF changes the UE access location from the MME to the MSC server based on the target cell ID

� The SRVCC IWF is collocated with an MSC server or deployed as a standalone entity. If the SRVCC IWF is deployed as a standalone entity, it functions as a proxy of the

EPCCS

IMS Core

SveMSC server(SRVCC IWF)

MSC Selects target MSC2

contained in the location update request.


functions as a proxy of the MSC server and performs conversion for signaling messages between the MSC server, SBC, and MME.

MME

MSC

UESRVCC IWF

Handover request

MSC

MSC

MSC1

Page43

NEs at the Core Layer - ATCF/ATGW� The ATCF/ATGW is located between the P-CSCF and I-CSCF/S-CSCF

and interworks with the SCC AS to provide eSRVCC.

� During a call, the ATCF or ATGW determines whether to anchor a call on the During a call, the ATCF or ATGW determines whether to anchor a call on the

media plane based on carriers' policies and terminal capabilities.

� During an eSRVCC handover, the ATCF or ATGW correlates a handover

request initiated by the SRVCC IWF with the anchored session, updates

session bearer information, and initiates a handover request to the SCC AS.

CSIMS Core SCC AS

SRVCCIWF

2G/3G

Remote UE


Signaling before a handover

Bearer before a handover

Signaling after a handover

Bearer after a handover

Local handover duration: < 300 ms

PS SBC

Handover

LTEATCF

ATGW

Change is not required.

Page44

NEs at the Access LayerNE Name Function

eMSC server(mAGCF)

Helps ICS subscribers in a CS domain to register with an IMS domain and provides basic and supplementary services for them.

S-GW/P-GW

• S-GW in an EPC domain: serves as an anchor point for the user plane between access networks in 3GPP. The S-GW is used as an interface to screen different access networks in 3GPP.

• P-GW in an EPC domain: serves as an anchor point between a 3GPP access network and non-3GPP access network. It provides an interface for interworking between a 3GPP access network and external PDN.


MMEImplements mobility management for LTE subscribers, including subscriber context and mobility status management, and temporary identity distribution.

Page45

Contents



3.2 VoLTE NE Functions



Interfaces in the IMS and CS domains and Interworking


Interfaces for Accessing


Contents






Huawei VoLTE Solution

Convergent SDB IMS Core

Presence/IM/DS/XDMSRCS9880

ATS(MMTel AS/SCC AS/IP-SM-GW/Anchor AS/IM

SSF)ATS9900

SCP

Legacy serviceApplication server

EMSiManager

M2000

O&M

Legacy

SBC(P-CSCF/A-BCF/A-BGF/ATCF/ATGW/E-CSCF)

SE2600/SE2900

PCRFUPCC

S-GW/P-GWUGW9811

MMEUSN9810

MRFPMRP6600

MGCFMSOFTX3000

eMSC server(SRVCC-IWF/CSFB proxy)

MSOFTX3000

I-CSCF/S-CSCF/MRFC

CSC3300

CS

EPC

M2000

CCFiCG9815

Provisioning GW

SPG2800

MGWUMG8900

HLR/IMS-HSS/SAE-HSS/ENUM /DNS

IM-MGWUMG8900

DMSTMS9950

Legacynetwork


UPCCUGW9811USN9810UMG8900

Terminal LTE CPELTE handset LTE data card + software client

LTE2G/3G 2G/3G LTE

Page50

High Integration

SE2600/SE2900


SE2600/SE2900

Unified Hardware Platform•The IMS domain, evolved packet core (EPC) domain, CS domain, and convergent HLR/HSS of Huawei VoLTE solution run on an ATCA-based Open Standards Telecom Architecture (OSTA) 2.0 platform, which improves hardware integration and simplifies network operation and maintenance.

IMS/MSC server/SingleSDB

EMS/RCS

IMSMSC server

IMS/ATS

UMG8900 P-GW/S-GW/SBC

maintenance.


MMESingleSDB

Platform: ATCA/ATAE Platform: UMG Platform: PGP

Page52

Unified Network Management


� The M2000/U2000 is deployed to manage all NEs in IMS, CS, and EPC networks in a unified

manner. The M2000/U2000 functions include monitoring alarms and collecting NE performance

data. With the M2000, operators can monitor, configure, and maintain the entire network

conveniently.

Page53

Solution 2: The Newly Deployed Convergent HSS\HLR Replaces the HLR on the Live Network

� Solution description

� The newly deployed HLR/HSS stores

data of 2G, 3G, 4G subscribers. A data of 2G, 3G, 4G subscribers. A

subscriber from the IMS, PS, and CS

domain can access the data.

Subscriber data stored on the HLR

on the live network is migrated to the

newly deployed convergent

HLR/HSS. Huawei HLR V900R006

or later can be upgraded to the


convergent HLR/HSS.

� The MSC and SGSN on the live

network update all routes and store

them in the convergent HLR/HSS.

In this solution, only SIM cards need to be changed .

Page54

Solution 3: The Newly Deployed Convergent HSS\HLR Coexists with the HLR, and VoLTE and 2G/3G Subscribers Use the Same Number Segments

� Solution description

� The newly deployed convergent HLR/HSS

manages 4G subscriber data. New VoLTEmanages 4G subscriber data. New VoLTE

subscribers can be defined on the

convergent HLR/HSS. Data of 2G/3G

subscribers who have subscribed to 4G

services is migrated from the HLR to the

convergent HLR/HSS. If 2G/3G subscribers

do not subscribe to 4G services, their data

is still stored in the HLR.

� Routing data for IMSIs and MSISDNs are

configured on the STP and SRF. If

subscribers have subscribed to 4G services,

messages are routed to the convergent

HLR/HSS. If subscribers do not subscribe

to 4G services, messages are routed to the

old HLR.

In this solution, only SIM cards need to be changed .

Summary

� This course describes:

� VoLTE solution basic concepts� VoLTE solution basic concepts

� VoLTE network evolution

� Huawei VoLTE solution architecture and NE functions

� Huawei VoLTE solution products and deployment solutions


AcronymsVoLTE voice over long term evolutionCSFB circuit switched fallbackSVLTE simultaneous voice and LTEOTT over-the-topCTAS common telecom application serverCTAS common telecom application serverT-ADS terminating access domain selectionEPC evolved packet core MO mobile originatingMT mobile terminatingLTE Long Term EvolutionIMS IP multimedia subsystemSAE system architecture evolutionSMS short message serviceUE user equipment RCS Rich Communication SuiteIM instant message


IM instant messageICS IMS centralized serviceSRVCC single radio voice call continuityeSRVCC enhanced single radio voice call continuitySCC AS Service Centralization and Continuity Application Server HSS home subscriber server

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Acronyms (Cont.)MME mobility management entityPS packet switchedCS circuit switchedATCF access transfer control functionATGW access transfer gatewayATGW access transfer gatewaymAGCF mobile access gateway control functionAGCF access gateway control functionCSCF call session control functionS-CSCF serving-call session control functionP-CSCF proxy-call session control functionI-CSCF interrogating-call session control functionMRFC multimedia resource function controllerMFFP multimedia resource function processorMGCF media gateway control functionAS application server


AS application server BGCF breakout gateway control function NAB Network Address BookCAB Convergent Address Book

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Thank youwww.huawei.com

introduction to the volte solution

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