INAP INAP Intelligent network application part protocolIntelligent network application part protocol

© Yiqun Xu & Zhiping Duan © Yiqun Xu & Zhiping Duan March 15 2002 March 15 2002

Architecture of INArchitecture of IN

Switch

Switching fabric

Call processing Digit Analysis

RoutingAnnouncement

Unit

Advanced Featureprocessing

Query processing (SSP)

Simple Tone Generator(IP)

Advanced Featureprocessing

SCP

SCP: Service Control Point

SSP: Service Switching Point

IP: Intelligent Peripheries

IN: Intelligent Network

IP

Announcement Unit and more

Overview of INAP(1)Overview of INAP(1) intelligent network application part protocolintelligent network application part protocol

SCF

SRF

SSFSwitches enhancedto support IN(interface with SCP and IP)

Service Logic

Routing database

VoiceINAP

INAP

INAP

DB

• Vendor independence to Telco • Open Interfaces

• Rapid, cost effective, and lower risk service deployment

• Ability to design and customise new services

Overview of INAP(1) Overview of INAP(1) intelligent network application part protocolintelligent network application part protocol

1. the main purpose of INAP is to define the information-flow format between different function entities

2. Information flows of the INAP can be defined between:SCF and SSF ,SCF and SRF, SCF and SDF which are located in different location, so that the whole service logic can be executed in the distributed system.

Relationship between different entitiesRelationship between different entities

– Service Switching Function (SSF)Service Switching Function (SSF)

– Service Control Function (SCF)Service Control Function (SCF)

– Specialized Resource Function (SRF)Specialized Resource Function (SRF)

– Service Data Function (SDF)Service Data Function (SDF)

Information Flows between two FEs consist either of a request/response pair or of a request alone.

Relationship between SCF - SSFRelationship between SCF - SSF

is established either as a result of sending a request for instruction to the SCF (SSF->SCF), or at the request of the SCF for initiation of a call(SCF->SSF)

is normally terminated at the request of the SCF. The SSF may also terminate the relationship

(e.g. in error cases).

Example:Example: Initial DP

IF is generated by the SSF when a trigger is detected at any DP in the IF is generated by the SSF when a trigger is detected at any DP in the BCSM, to request instructions from the SCF.BCSM, to request instructions from the SCF.

Relationship between SCF -SRF

is established by the SRF sending an “assist request instructions from SRF” to the SCF. The SCF can now instruct the SRF to perform some interaction with an end user .

is terminated by the SCF. The establishment of this relationship must be preceded by

the establishment of a relationship between the SCF and SSF.

Example:Example: PromptAndCollectUserInformationAfter SRF receive the instructions from SCF, SRF will be used to After SRF receive the instructions from SCF, SRF will be used to interact with the user (play announcement and collect user’s input)interact with the user (play announcement and collect user’s input)

Relationship between SCF-SDFRelationship between SCF-SDF

is established at the request of SCF when SCF requires to retrieve or modify some data contained within the SDF

is terminated by the SDF

Note: SDF is a remote database application, not the database attached with SCP.

Example:Example: AuthenticateResult1. SCF is asked to retrieve or modify data within SDF1. SCF is asked to retrieve or modify data within SDF

2.SDF sends information flow to a SCF to inform SCF of the 2.SDF sends information flow to a SCF to inform SCF of the authentication result authentication result

Overview of INAP(2)Overview of INAP(2) intelligent network application part protocolintelligent network application part protocol

INAP is an application-layer protocol used in Intelligent Networks. INAP is an application-layer protocol used in Intelligent Networks. This protocol runs on top of TCAP and is deployed using SS7 (or This protocol runs on top of TCAP and is deployed using SS7 (or

other signaling environments)other signaling environments)

SCCP

MTP

TCAP

ISUPI NAP

M

A

P

INAP Protocol ArchitectureINAP Protocol Architecture---Single Interactions---Single Interactions

(The SAO represents the SACF plus INAP to be used over a single interaction between a pair of PE’s.)

Application Process

ASE’sSACF TCAP

SCCP

MTP

SAOSAO: Single association object

SACF: Single association control function

ASE: Application service element

INAP: the collection of specifications of all in ASE’s

TCAP:transaction capabilities application part

SCCP: service switching and control point

MTP: Message Transfer Part

INAP Protocol ArchitectureINAP Protocol Architecture---Multiple coordinated---Multiple coordinated

(interactions will be happened among several SAO’s, MACF will be offered to provide a coordinating function among those SAO’s, each of which interacts with an SAO in a remote PE.)

SAO: Single association object

SACF: Single association control function

MACF:Multiple association control function

ASE: Application service element

INAP: the collection of specifications of all in ASE’s

TCAP:transaction capabilities application part

SCCP: service switching and control point

MTP: Message Transfer Part

Application Process

SCCP

MTP

ASE’sSACF TCAP

SAO

MACF

ASE’sSACF TCAP

SAO

SACF/MACF rulesSACF/MACF rules

Stipulate the format of operations’ sequential/parallel execution:

Operations performed in parallel are to be included in the same message(case A)

Operations performed sequentially are to be controlled in two separate message(case B)

For example, charging operations may be synchronized with other operations and CallInformationRequest operation may have to wait for CallInformationReport operation.

800 Service (example using INAP)

PSTN

DB2. Launches the 800 Service

4. Rings the callee party

SCP

SSP/SG

1. Dials 800#

3. SCP find the real number in DB and inform SSP to reach callee partyINAP

INAP

Evolution of INAP(1)Evolution of INAP(1)

The evolution of INAP depends on The evolution of INAP depends on the development of IN Capability the development of IN Capability Set.Set.

Evolution of INAP(2)Evolution of INAP(2) INAP for IN CS-1 INAP for IN CS-1

Q.1208: general rules for INAP ; Q.1218: refined (CS-1R) as Q.1208: general rules for INAP ; Q.1218: refined (CS-1R) as describeddescribed

Interface: Interface: » Service Switching Function (SSF)Service Switching Function (SSF)» Service Control Function (SCF)Service Control Function (SCF)» Specialized Resource Function (SRF)Specialized Resource Function (SRF)» Service Data Function (SDF)Service Data Function (SDF)

Relationship :Relationship :» SCF-SSFSCF-SSF» SCF-SRFSCF-SRF» SCF-SDFSCF-SDF

Evolution of INAP(3)Evolution of INAP(3)INAP for IN CS-2 (Q.1228)INAP for IN CS-2 (Q.1228)

InterfaceInterface» Service Switching Function (SSF).

» Service Control Function (SCF).

» Specialized Resource Function (SRF).

» Service Data Function (SDF).

» Call Unrelated Service Function (CUSF).

Relationship » SCF-SCF

» SDF-SDF

» SCF-CUSF

To define message format between different To define message format between different function entities in order to execute the whole function entities in order to execute the whole service logic in the distributed systems.service logic in the distributed systems.

To support SIBs when they are mapped into DFPTo support SIBs when they are mapped into DFP …………

Operation, Error and Data typeOperation, Error and Data type…………

Why INAP:

ApplyCharging procedureApplyCharging procedureApplyCharging ::= OPERATION

ARGUMENTApplyChargingArg

ERRORS {MissingParameter,UnexpectedComponentSequence,UnexpectedParameter,UnexpectedDataValue, ParameterOutOfRange,SystemFailure,TaskRefused}

-- Direction: SCF -> SSF, Timer: Tac -- This operation is used for interacting from the SCF with the SSF charging

mechanisms.

ApplyChargingReport procedureApplyChargingReport procedure

ApplyChargingReport ::= OPERATIONARGUMENT

ApplyChargingReportArgERRORS {

MissingParameter,UnexpectedComponentSequence,UnexpectedParameter,UnexpectedDataValue,ParameterOutOfRange,SystemFailure,TaskRefused}

-- Direction: SSF -> SCF, Timer: Tacr -- This operation is used by the SSF to report to the SCF the occurrence of a specific

charging event as requested by the SCF using the ApplyCharging operation .

1

2

PromptAndCollectUserInformation: SCF inform SRF to play announcement and collect user’s input, SRF should return the result of this operation or error message to SCF at the end of this action.

ApplyCharging: SCF inform SSF begin to charge and tell SSF the charging policy as well. If something is wrong, then SSF will report this error to SCF immediately, or it will begin to execute this action, and report the result to SCF using another operation procedure “ApplyChargingReport” when the call terminates.

FE FE

operation

response

FE FE

operation

error

FE FE

operation

error

Four kinds of operationsFour kinds of operations

Activetest operation: SCF send Activetest to SSF, if everything is ok, SSF will return a response to SCF immediately, if something is wrong, there should be no any response at all. So this operation only expects “successful result”.

3

4 Release operationContinue operation

FE FE

operation

response

FE FEoperation

How does INAP work(1)How does INAP work(1) SCP Alice Bob SSP

Play announcement and collect information

Invoke service logic

PromptandCollectUserInformation

Dial an calling card access number

InitialDP

Return the result

ApplyCharging ; Connect

Alice and Bob are talking…

Bob hands upTdisconnect ;ApplyChargingReport

Ring Bob and Bob pick up the hook

Release

Busy tone

How does INAP work(2)How does INAP work(2)

SSF send InitialDP to SCF and invoke the service logic. Applycharging and Connect are sent to SSP in parallel. Tdisconnect and ApplyChargingReport are sent to SCP in

parallel.

How INAP message transmit through SS7How INAP message transmit through SS7

INAP operation and its INAP operation and its parameter should be put parameter should be put within one component within one component

INAP encapsulated as INAP encapsulated as component by TACP and component by TACP and then transmitted by TCAP.then transmitted by TCAP.

One TCAP message can One TCAP message can transmit several components transmit several components at the same timeat the same time

SCCP

MTP

TCAP

ISUP I NAP

M

A

P

Interactions between ISUP and INAPInteractions between ISUP and INAP

This interaction takes place in the CCF and SSF. – • detection point processing in the CCF;– • receipt of INAP operations in the SSF.

ISUP: SuISUP: Suppppoortrtss the call control function the call control function. . exchanges exchanges signals between SSPs and establishes the voice signals between SSPs and establishes the voice path between SSPs.path between SSPs.

CCF: Handles all normal calls by providing the CCF: Handles all normal calls by providing the processing and the control of call or connection processing and the control of call or connection between network subscribers.between network subscribers.

SSF: Acts as the interface between CCF and SCFSSF: Acts as the interface between CCF and SCF

T11103720-99

ISUP ISUPDLE

SSP

CCF

SSF

INAP

SCP

SCF

OLEAccess

SignallingAccessSignalling

Why interaction happens?Why interaction happens?

OLE: Originating Local Exchange

DLE: Destination Local Exchange

Explanation of last slideExplanation of last slide

1. The signaling between SSPs are transmitted by 1. The signaling between SSPs are transmitted by ISUPISUP

2. Here we consider OLE and DLE as SSPS as 2. Here we consider OLE and DLE as SSPS as well.well.

3. If the SSF(located in OLE) have to invoke a 3. If the SSF(located in OLE) have to invoke a service which happens to locate in a SCP that service which happens to locate in a SCP that there is no direct link from the local SSP(OLE) there is no direct link from the local SSP(OLE) and that SCP, then interaction between INAP and and that SCP, then interaction between INAP and ISUP happens…ISUP happens…

Where the interaction happensWhere the interaction happens

The interaction between ISUP and INAP takes place The interaction between ISUP and INAP takes place in the CCF and SSF:in the CCF and SSF:

• • Detection point processing in the CCFDetection point processing in the CCF

example:example:

T_Mid_CallT_Mid_Call

• • Receipt of INAP operations in the SSFReceipt of INAP operations in the SSF

example:example:

ActivateServiceFilteringActivateServiceFiltering operation: ACM operation: ACM message or REL message will be sent with message or REL message will be sent with different parameters.different parameters.

SSF and CCF

SSP

ISDN/PSTNlink

MACF

ISUP

SCCP

MTP

SS No. 7link

SRF

IP

MACF

ISUP

SCCP

MTP

SCF

SCP

MACF

SACF TCAP

SCCP

MTP

INAP

SACF TCAP

INAP

SACF TCAP

INAP

SACF TCAP

INAP

SS No. 7link

SS No. 7link

SS No.7

network

Remote ssp

Scenario: IP is separated…Scenario: IP is separated…

Explanation of last scenarioExplanation of last scenario

SSP connect to remote SSP and IP via SSP connect to remote SSP and IP via ISUP, SCP can not deal with ISUP signal ISUP, SCP can not deal with ISUP signal directly.directly.

There are 2 possibilities for SCP There are 2 possibilities for SCP communicate with IP: 1. transfer INAP communicate with IP: 1. transfer INAP messages via SS7 directly. 2. Transfer messages via SS7 directly. 2. Transfer INAP message to SSP, and SSP send ISUP INAP message to SSP, and SSP send ISUP signal to IP.signal to IP.

Scenario: Scenario: IP attached to an assisting SSPIP attached to an assisting SSP

T11103750-99

ISUP

SCP

SCF

OLE

SSP

CCF

SSF

INAP

ISUP

SSP

CCF

SSF

SRF

IP

INAP

AccessSignalling

DSS1 orimplement.dependentinterface

OLE: Originating Local Exchange

Interaction between INAP and SIPInteraction between INAP and SIP

SIP, Session Initiation ProtocolSIP, Session Initiation Protocol , is a new signaling , is a new signaling protocol for establishing real-time calls and conferences protocol for establishing real-time calls and conferences over Internet Protocol networks. over Internet Protocol networks.

SIP is also an application layer signaling system, with the SIP is also an application layer signaling system, with the interaction between INAP and SIP, IP network can interaction between INAP and SIP, IP network can

communicate with traditional PSTNcommunicate with traditional PSTN..

Mapping INAP messages/parameters into (sequences of) Mapping INAP messages/parameters into (sequences of) SIP messages/parameters and vice versa. SIP messages/parameters and vice versa.

Benefit of this interactionBenefit of this interaction

The existing IN service can migrate to IP The existing IN service can migrate to IP telephonytelephony

IP architecture may borrow service concepts from IP architecture may borrow service concepts from IN potentiallyIN potentially

Unified Messaging Unified Messaging

Service Deployed In IP Networks

SCF SDF

SSFCCF mapping

SIP Proxy Server

SOFT SSP

Extended SIP Proxy Server

SIP User Agent

Terminal

SCN SCN IP NETWORKIP NETWORKGateway

INAP

SIP

Terminating Call with INAP Interaction

SCP Extended Proxy Server

CALLEE

InitialDP

Service logic

INAP instruction

INVITE

INVITE

From SIP server/user agent

IN service located in PSTNIN service located in PSTN

INAP AU

SSF

SCF

SRF

SIP Proxy ServerService Switching Point

PSTN

Services

VoIP

INAP

INAP

INAP

SIP SIP

RTPVoice Path

Service Gateway

SCP

•Service Control Point (SCP) - SCP has Services applicable for PSTN and VoIP (SIP) networks

•Specialized Resource Function (SRF) - SRF provides media resources

•Service Switching Function (SSF) - SSF invokes the services on SCP for PSTN and VoIP networks

•Service Gateway (SG) - SG interface with SIP proxy server. SG has INAP AU and the SSF functionality

•INAP AU - The INAP AU maps SIP state machine to the IN call model

Entities in Converged Network

ReferenceReference

ITU-T Q.1218ITU-T Q.1218 ITU-T Q.1600ITU-T Q.1600 InterworkingInterworking between SIP and INAP between SIP and INAP SIP/IN SIP/IN InterworkingInterworking INAP Support of the SIP/SDP ArchitectureINAP Support of the SIP/SDP Architecture

Thank you!Thank you!

Any question