Wireless Intelligent Network WIN Tutorial

Wireless Intelligent Network (WIN)

Tutorial

What is the Wireless Intelligent Network (WIN)?

• The extension of wireline Intelligent Network(IN) concepts to IS-41 based wireless network

• An architecture that separates the service logic and/or feature functionality from the wireless network switch and places that functionality in other platforms in the network

• The specific work of the Telecommunications Industry Association’s (TIA) WIN Task Group(TR- 45.2.2.4)

What is IS-41?

MSC MSC

HLR

MSC MSC

HLR

PSTN

Wireless Operator in U.S.

Wireless Operator in Latin America

IS-41 Intersystem Operations

MSC EIR

MSC PSTNBSMS

HLRAC VLR ISDN

MC MC VLRSME SME

IS-41 Intersystem Operations

• Network Elements– Mobile station(MS)

– Base station (BS)

– Mobile switching center (MSC)

– Home location register (HLR)

– Visitor location register (VLR)

– Authentication center (AC)

– Equipment identity register (EIR)

– Message center (MC)

– Short message entity (SME)

IS-41 Network Elements

• Mobile Station (MS)– The interface equipment used to terminate the radio

path at the user side. The MS provides the user the capabilities to access network services.

• Mobile Switching Center(MSC)– Automatic system which constitutes the interface for

user traffic between the wireless network and other public switched networks, or other MSCs in the same or other wireless networks


• Home Location Register (HLR)– Location register to which a user’s identity is assigned for

record purposes such as:• Subscriber information• Mobile station information

– Provides service control and mobility management for subscribers

– HLR may or may not be located within, and be indistinguishable from, an MSC

– HLR may serve more than one MSC


• Authentication Center (AC)– Element that manages the authentication

information related to the mobile station– The AC may or may not be located within, and be

indistinguishable from, an HLR


• Visitor Location Register (VLR)– Location register used by an MSC to retrieve

information for handling calls to or from a visiting mobile station user

– Provides mobility management for subscribers in visited system

– VLR may or may not be located within, and be indistinguishable from, an MSC

– VLR may serve more than one MSC


• Message Center (MC)– The message center stores and forwards short messages– It may also provide supplementary services for short

message services

• Short Message Entity (SME)– The short message entity composes and decomposes

short messages.– An SME may or may not be located within, and be

indistinguishable from, an HLR, MC, VLR, MS or MSC

Driving Forces for WIN

• Greater control of wireless network functionality

• Faster feature introduction• Flexibility to choose which features are

developed• Customized services for subscribers• Competitive solutions from multiple vendors

WIN Objectives

• Provide capabilities for rapid service introduction, service creation and service customization

• Service-independent WIN architecture• Compatible with existing wireless network

architecture

WIN Requirements

• Flexible distribution of service logic supporting functions– Wireless service provider can choose a WIN

architecture to match network topology

• New WIN-based services must coexist with existing wireless services– “Switch”-based services (e.g., call waiting)– Existing “HLR” based services (e.g., call forwarding)

WIN Requirements

• Transparent to subscriber– WIN-based services– “Switch”-based services– “HLR”-based services

• Seamless services– Home– Roaming

Intelligent Network Service

Dials 1-800-333-4444

12

3

4

56

7

313-456-6789 Rings

SSP SSP

STP

SCP

WIN Concepts

• Based on wireline IN concepts– During call processing, switch can detect events

(triggers) at various points where call processing can be interrupted to request IN processing (e.g., at origination or completion of dialing)

– The switch then queries IN service logic for further instructions

– Service logic can be programmed to provide new services

IN Architecture Elements

I P

SSP SCP

SSP

SN

Service

Subscriber

IN signaling

Voice Channel


• Service Switching Point (SSP)– Major function of the SSP is to detect events

during call processing, called triggers, that indicate an IN call event

– After triggering, the SSP suspends call processing and starts a series of transactions with the SCP to determine the handling of the call


• Service Control Point (SCP)– Real-time database and transaction processing

system that provides service control and service data functions

– Performs subscriber or application specific service logic in response to a query from SSP and then sends back instructions to perform specified functions and how to continue call processing

– Provides mechanisms for introducing new services and customizing services and features


• Intelligent Peripheral (IP)– Performs specialized resource functions such as:

• Playing announcements• Collecting digits• Speech recognition• Recording and storing voice messages• Facsimile services...

– Under the control of service logic


• Service Node (SN)– A programmable network node that allows the

service provider to create new circuit related services

– Provides both service logic processing and call terminations for specialized resource functions

– Combines capabilities of SCP and IP

IN Triggers

• Call termination triggers– Called party busy– No answer

• Call origination triggers– Calling party– Dialed number

• Trigger categories– Subscribed (individual subscriber-based)– Office/group

Services Supported by IS-41C

• Call delivery• Call forwarding - busy• Call forwarding - default• Call forwarding - no answer• Call forwarding - unconditional• Call transfer• Call waiting• Calling number ID presentation• Calling number ID restriction• Conference calling• Do not disturb• Flexible alerting

• Message waiting notification• Mobile access hunting• Password call acceptance• Preferred language• Priority access & channel

assignment• Remote feature control• Selective call acceptance• Subscriber PIN access & intercept• Three-way calling• Voice message retrieval• Voice privacy• Short message services

WIN Architecture of IS-41

• IS-41 architecture is a WIN architecture– Mobile switching center (MSC) is a service switching

point• Call origination/termination triggers• Queries to service logic for instructions• Specialized resource functions

– Home location register (HLR) provides service control, service data and mobility management functions

– Visitor location register (VLR) provides subscriber profile data and other mobility management functions

WIN Capabilities of IS-41C

• Profile (HLR to Serving System)– Profile follows the subscriber– Profile can be updated at any time

• Profile contains:– Service profile– Origination triggers– Termination triggers


• Service profile (switch based services)– Origination indicator

• Type of call originations allowed

– Termination restrictions• Type of call terminations allowed

– Pre-subscribed long distance carrier– Preferred language indicator


• Service profile (switch-based services)– Calling features

• Call waiting• Three-way calling• Calling number identification presentation• Calling number identification restriction• Call transfer


• Call origination triggers (Serving MSC)– Triggers for specified call origination events

• All origination attempts• Local call attempts• Toll call attempts• International call attempts• Dialed numbers with specific number of digits• Dialed numbers beginning with *,**,#,## digits• e.g., dialed international call


• Call termination triggers (Serving MSC)– Triggers for specified call termination events

• Busy• No page response• No answer• Not reachable• Routing failure

• Call termination triggers (originating MSC)– Incoming call to a mobile station– Call redirection

WIN Capabilities of IS-41CWIN Capabilities of IS-41C

IS-41 Queries to WIN Services

• Location request– Originating MSC to HLR– Triggered by calls to mobile stations

• Transfer-to-number request– Originating MSC/serving MSC to HLR– Triggered by an event corresponding to

termination Triggers received from HLR

IS-41 Queries to WIN Services

• Origination request– Serving MSC to HLR– Triggered by call origination event corresponding

to origination triggers received from the HLR

IS-41 User Interaction Control

• Remote user interaction directive– HLR to originating or serving MSC– Controls announcement played and collection of

digits• Subscribed

• Feature request– Serving MSC to HLR– Triggered by feature request made by user

Registration Notification

MSC

VLR HLR VLR

MSCMS

system access

REGNOT

REGNOT

regnot

regnotREGCANC

regcanc

Old Serving System New Serving System

Call Forwarding - Busy

MSC

HLR VLR

MSC

Originating Serving

call origination

LOCREQ[CALLED #]

ROUTREQ[MIN,ESN]

ROUTREQ

routreq[busy]

routreq[busy]

locreq[CF#]call setup

Selective Call Acceptance

MSC

HLR VLR

MSC

Originating Serving

call origination

LOCREQ[CALLING#,CALLED #]

locreq[CF#]

call forward

Subscriber PIN Intercept

MSC

HLR

Serving System

mobile call origination

ORIGREQ[DIGITS]

RUIDIR[ANNLIST, DIGITCC]

VLR

play announcement and collect digits

ruidir[DIGITS]

origreq[continue]

.

.

Feature Control Request

MSC

HLR

Serving System

feature access

FEATREQ[DIGITS]

featreq

VLR

tone or announcement

QUALDIR[PROFILE]

qualdir

.

.

.

Evolution to WIN

• IS-41 architecture and capabilities allow WIN-oriented services– Vendors have developed new and enhanced services

based on IS-41 intersystem operations• In a multi-vendor environment

– Wireless service providers have deployed SCPs in their networks• HLR functionality• Enhanced services• Customized services

Evolution to WIN

• Examples of WIN-based services– Call origination services based on:

• Calling party

• Location of caller

• Dialed number

– Call origination service examples:• Virtual network services

• Automatic retry on busy

Evolution to WIN

• Examples of WIN-based services– Call terminating services based on:

• Incoming call information (e.g. calling party)

• Mobile station location and status (e.g., busy)

• Mobile’s response to incoming call (e.g, no answer)

• Time of day

• ...

– Call terminating service examples:• Enhanced call screening

• Enhanced call forwarding

Evolution to WIN

• Examples of WIN-based services– Non-call-related services based on:

• Mobile station location• Mobile station status

– Non-call-related service example:• Location tracking

Current WIN Standards Work

• Add SCP, IP and SN elements to IS-41 network– Use existing IS-41 signaling network (SS7)– Use existing voice channel interconnections– Build on existing intersystem operations for

interactions with SCP and IP– IP supports broader range of resource functions than

currently specified for IS-41– MSCs can interact directly with SCP service logic

WIN Architecture

SCP

MSC PSTNBSMS

HLRAC VLR ISDN

MC MCVLR

SME SME

MSC IPSCP

SNHLRIP

EIR

Current WIN Standards Work

• WIN network element interactions– MSC to/from HLR/SCP/IP/SN– HLR to/from SCP/IP/SN– SCP to/from SCP/IP/SN

• Distribution of service control logic across multiple network elements (HLR, SCPs, SNs)

MSC Call Processing

• MSC call processing model – Basic call state models (BCSMs)

• Originating call model• Terminating call model

– Points in call (PICs)

– Detection points (DPs)

– PIC to DP transitions

– Based on ITU-T Q.1244 recommendations for CS-2

Originating BCSM

Route_Select_Failure DP

Collected_Information DP

invalid_information

Analyzed_Information DP

authorize_route_failure

O_Called_Party_Busy DP

O_Term_Seized DPO_Mid_Call DP

route_failure

Select_Route

Authorize_Call_Setup

Send_Call

Analyze_Information

.

.

.

.

.

.

Terminating BCSM

.

.

.

Termination_Attempt_Authorized DP

T_No_Answer DP

Facility_Selected_and_Available DP

presentation_failure

Call_Accepted DP

Termination_Attempt_DP

termination_denied

SS7_failure

T_Busy DP

Select_Facility

Authorize_Termination_Attempt

Present_Call

T_Alerting

call_rejected

.

.

.

Distributed Functional Plane

• WIN functional architecture– Functional entities

• Call control function (CCF)• Service switching function (SSF)• Service control function (SCF)• Service data function (SDF)• Specialized resource function (SRF)• Radio access control function (RACF)• Radio control function (RCF)

Distributed Functional Plane

SMAF SMF SCEF

SRFSCFSDF

LRF

SSF

CCF

RACF RCF

RTF

SCF

ACF

CCF

RACF

to any FE

ACF

LRF

Feature and Service Interaction Management

• Feature and service interaction management– Services for single subscriber can be distributed

across multiple network elements that provide service control

– Have to manage:• Feature precedence• Feature interaction• Feature data• Feature control

Feature and Service Interaction Management

FIM

BCM

SBSL iSBSL j

SSF/CCF

SCF

FSLP iFSLP j

FSLPk

SIM

SCF

FSLPxFSLPy

FSLPz

SIM

• Map existing IS-41C triggers to WIN DPs• Adding new call processing triggers and

trigger destinations for WIN

WIN IS-41 Operations

• New IS-41 operations– Seize resource

• HLR/SCP to IP (SCF to SRF)

– Connect resource • HLR/SCP/SN to MSC (SCF to SSF)

– Instruction requested• IP to HLR/SCP (SRF to SCF)

– Disconnect resource• HLR/SCP/SN to MSC (SCF to SSF)


• New IS-41 operations– Reset timer

• HLR/SCP/SN to MSC (SCF to SSF)

– Search• HLR/SCP/SN to HLR/SCP/SN (SCF to SDF)

– Modify• HLR/SCP/SN to HLR/SCP/SN (SCF to SDF)

– Service request• HLR/SCP/SN to HLR/SCP/SN (SCF to SCF)


• New IS-41 operations– Termination request

• MSC to HLR/SCP/SN (SSF to SCF)

• New IS-41 parameters• Network reference model• Stage 2 descriptions• Stage 3 descriptions


WIN Services

• New WIN-based features– Calling name identification presentation– Incoming call screening– Voice controlled services

• Voice-controlled feature activation and control• Voice-controlled dialing• Voice-based user authentication• Speech to text conversion (short message creation)

Calling Name Identification Presentation

• Displays the name of the calling party on the called party’s terminal. The calling party name information is derived from the calling number information (CNI) which is generally provided to the terminating network as part of basic call setup.

Calling Name Identification Presentation

MSC HLR VLR MSC MSSCP

LOCREQ[CNIDigits]

ROUTEREQ[MIN,CNIdigits]ROUTEREQ[MIN,CNIdigits]

routereq[TLDN]

routereq[TLDN]

locreq[TERMLIST]

call setup

TERMREQ

termreq[ACTCODE,DISTEXT]

alert(CNAP info)

call answer

Originating System Serving System

Incoming Call Screening - ICS

• ICS is an enhanced service which provides the capability of routing or blocking of incoming calls to a subscriber. The ICS service logic resides on the SCP which screens the call based on screening factors (e.g., CLID, serving MSC) and selects one of many possible terminating actions (e.g., forward call to message center).

Incoming Call Screening

MSC HLR SCP

LOCREQ[DGTSDIAL,CNIdigits]

SERVREQ[DGTSDIAL,SRVLIST,CNIdigits]

servreq[TERMACT,TERMLIST]

locreq[TERMLIST]

call setup to VMS

Originating System

call origination

• Allows the mobile subscriber to control features (e.g., CFU, CFB, MWI) by using voice commands. The subscriber dials a star code (e.g., *33) associated with an origination trigger for the service. The call is routed to an automatic speech recognition device that prompts the caller for feature control information and carries out the request.

Voice Controlled Feature Control

Voice Controlled Feature Control

Serving SystemMSC VLR SN HLR

call originationORREQ

CONNECTRESOURCE

prompt for feature control

collect feature control

call setup

clear call

FEATREQ

featreq

QUALDIRQUALDIR

qualdir qualdir

announce feature control success

orreq[ACTCODE]

Future WIN Standards Work

• International standards• Mobility and radio access triggers• Add wireline equivalent IN call processing

triggers• Wireless/wireline integration

Documents

Wireless Intelligent Network WIN Tutorial