IN_PPT

INAP Intelligent network application part protocol

Yiqun Xu & Zhiping Duan March 15 2002

Architecture of INSwitchQuery processing (SSP)Simple Tone Generator(IP)SCP: Service Control PointSSP: Service Switching PointIP: Intelligent PeripheriesIN: Intelligent Network

Overview of INAP(1) intelligent network application part protocolSCFSRFSSFSwitches enhancedto support IN(interface with SCP and IP)Service LogicRouting databaseVoiceINAPINAPINAPDB 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) intelligent network application part protocol1. the main purpose of INAP is to define the information-flow format between different function entities2. 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 entitiesService Switching Function (SSF)Service Control Function (SCF)Specialized Resource Function (SRF)Service Data Function (SDF)Information Flows between two FEs consist either of a request/response pair or of a request alone.

Relationship between SCF - SSFis 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:Initial DPIF is generated by the SSF when a trigger is detected at any DP in the BCSM, to request instructions from the SCF.

Relationship between SCF -SRFis 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:PromptAndCollectUserInformationAfter SRF receive the instructions from SCF, SRF will be used to interact with the user (play announcement and collect users input)

Relationship between SCF-SDFis established at the request of SCF when SCF requires to retrieve or modify some data contained within the SDFis terminated by the SDF

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

Example:AuthenticateResult1. SCF is asked to retrieve or modify data within SDF2.SDF sends information flow to a SCF to inform SCF of the authentication result

Overview of INAP(2) intelligent network application part protocolINAP is an application-layer protocol used in Intelligent Networks. This protocol runs on top of TCAP and is deployed using SS7 (or other signaling environments)

INAP Protocol Architecture---Single Interactions(The SAO represents the SACF plus INAP to be used over a single interaction between a pair of PEs.)SAO: Single association objectSACF: Single association control functionASE: Application service elementINAP: the collection of specifications of all in ASEsTCAP:transaction capabilities application partSCCP: service switching and control pointMTP: Message Transfer Part

INAP Protocol Architecture---Multiple coordinated(interactions will be happened among several SAOs, MACF will be offered to provide a coordinating function among those SAOs, each of which interacts with an SAO in a remote PE.)

SAO: Single association objectSACF: Single association control functionMACF:Multiple association control functionASE: Application service elementINAP: the collection of specifications of all in ASEsTCAP:transaction capabilities application partSCCP: service switching and control pointMTP: Message Transfer Part

SACF/MACF rulesStipulate 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)PSTNDBSCPSSP/SGINAPINAP

Evolution of INAP(1)

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

Evolution of INAP(2) INAP for IN CS-1Q.1208: general rules for INAP ; Q.1218: refined (CS-1R) as describedInterface: Service Switching Function (SSF)Service Control Function (SCF)Specialized Resource Function (SRF)Service Data Function (SDF)

Relationship :SCF-SSFSCF-SRFSCF-SDF

Evolution of INAP(3)INAP for IN CS-2 (Q.1228)InterfaceService Switching Function (SSF).Service Control Function (SCF).Specialized Resource Function (SRF).Service Data Function (SDF).Call Unrelated Service Function (CUSF).

Relationship SCF-SCFSDF-SDFSCF-CUSF

To define message format between different function entities in order to execute the whole service logic in the distributed systems.To support SIBs when they are mapped into DFPOperation, Error and Data typeWhy INAP:

ApplyCharging procedureApplyCharging ::= OPERATIONARGUMENTApplyChargingArgERRORS {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 procedure

ApplyChargingReport ::= OPERATIONARGUMENTApplyChargingReportArgERRORS {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 .

12 PromptAndCollectUserInformation: SCF inform SRF to play announcement and collect users 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.Four 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.34Release operationContinue operation

How does INAP work(1)

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 SS7 INAP operation and its parameter should be put within one component INAP encapsulated as component by TACP and then transmitted by TCAP.One TCAP message can transmit several components at the same timeSCCPMTPTCAPISUP I NAPMAP

Interactions between ISUP and INAPThis interaction takes place in the CCF and SSF. detection point processing in the CCF; receipt of INAP operations in the SSF.ISUP: Supports the call control function. exchanges signals between SSPs and establishes the voice path between SSPs.CCF: Handles all normal calls by providing the processing and the control of call or connection between network subscribers.SSF: Acts as the interface between CCF and SCF

T11103720-99Why interaction happens?OLE: Originating Local ExchangeDLE: Destination Local Exchange

Explanation of last slide1. The signaling between SSPs are transmitted by ISUP2. Here we consider OLE and DLE as SSPS as well.3. If the SSF(located in OLE) have to invoke a service which happens to locate in a SCP that there is no direct link from the local SSP(OLE) and that SCP, then interaction between INAP and ISUP happens

Where the interaction happensThe interaction between ISUP and INAP takes place in the CCF and SSF: Detection point processing in the CCF example: T_Mid_Call Receipt of INAP operations in the SSF example: ActivateServiceFiltering operation: ACM message or REL message will be sent with different parameters.

Scenario: IP is separated

Explanation of last scenarioSSP connect to remote SSP and IP via ISUP, SCP can not deal with ISUP signal directly.There are 2 possibilities for SCP communicate with IP: 1. transfer INAP messages via SS7 directly. 2. Transfer INAP message to SSP, and SSP send ISUP signal to IP.

Scenario: IP attached to an assisting SSP T11103750-99OLE: Originating Local Exchange

Interaction between INAP and SIPSIP, Session Initiation Protocol, is a new signaling protocol for establishing real-time calls and conferences over Internet Protocol networks.

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

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

Benefit of this interactionThe existing IN service can migrate to IP telephonyIP architecture may borrow service concepts from IN potentiallyUnified Messaging

Service Deployed In IP Networks

Terminating Call with INAP Interaction

IN service located in PSTN

Service Control Point (SCP) - SCP has Services applicable for PSTN and VoIP (SIP) networksSpecialized Resource Function (SRF) - SRF provides media resourcesService Switching Function (SSF) - SSF invokes the services on SCP for PSTN and VoIP networksService Gateway (SG) - SG interface with SIP proxy server. SG has INAP AU and the SSF functionalityINAP AU - The INAP AU maps SIP state machine to the IN call modelEntities in Converged Network

Reference ITU-T Q.1218ITU-T Q.1600Interworking between SIP and INAPSIP/IN InterworkingINAP Support of the SIP/SDP Architecture

Thank you!Any question

*This protocol is defined by ITU-T(International Telecommunication Union, Standardization Sector) and it is used in Intelligent Network.*First we briefly review the architecture of IN. IN is built based on the traditional telephone network.1. In the traditional telephone system, the switching systems (known as 'switches') perform the basic call processing. 2. Each supplementary service is non-reusable, Any small change or introduction of a new service also involved extensive testing.3. To solve these problems, the service logic and the voice resources moved to an independent box out of the switch communicating with the switch4.Intelligence here means, Services were developed and supplied more efficiently because they are taken out of the switch and placed in computer nodes that are distributed throughout the network.

**INAP will be deployed between these four functional entities(SSF, SCF, SRF, and SDF) in CS-1.2.Information Flows between two FEs either consist of a request/response pair or of a request alone.

Especially, SCF is the control center in IN and INAP, so we will show the relationship between SCF and other Functional Entities,

*INAP will be deployed between these four functional entities(SSF, SCF, SRF, and SDF) in CS-1.2.Information Flows between two FEs either consist of a request/response pair or of a request alone.

Especially, SCF is the control center in IN and INAP, so we will show the relationship between SCF and other Functional Entities,

*When the SSF receives call-related IEs from the SCF, it substitutes these IEs for the corresponding call information, and retains all other call information. This applies to ALL call processing-related messages.

For IN CS-1, a single SCF may have concurrent relationships with multiple SSFs. A single SSF may only have a relationship with one SCF at a time for any given call.

Detection Point**Confirm the result of authentication by SDF*In the view of point of OSI reference model, INAP is an application-layer protocol, and runs on top of TCAP.

INAP: intelligent network application partMAP: mobile application partISUP: integrated services digital network user part(between SSP and SSP)TCAP:transaction capabilities application part(service-related information exchange)SCCP: service switching and control point(addressing and routing)MTP: Message Transfer Part( Routing, error detection and correction, message sequencing)ROSE: remote operation service element*1. 2. SACF provides a coordination function by using ASEs**In some cases, it is necessary to determine whether operations should be performed sequentially or in parallel (synchronized). *800 service is an typical example for using INAP in telecommunication. **In the recommendation of Q.1208(general rules) of IN CS-1 and Q.1218(refined rules)of IN CS-1, interfaces (SSF, SCF, SRF and SDF) were defined and interaction operations between these entities were also defined (SCF-SSF, SCF-SDF, SCF-SRF) in the existing ISDN/PSTN.*General function extensions of the existed functional entities, supports and distributed data management.Explicit supplementary service feature interaction supportCompatibility check

CUSF: support non-call related interactions between users and the SCF

CS-3, CS-4 are ongoing and will be fulfilled in future.*Charging SIB define 6 kinds of information flow between SCF and SSF,*Whatever the result of this operation is, the responding FE should return the result to the invoking FEThe responding FE only return the error message to the invoking FE *3. The responding FE only return the successful result. When a call last very long time, there are two possibilities, one is that this is really a long call, the other is something is wrong and the process is in pending. In order to find what happened, SCF will send Activetest.4. The invoking FE just send the operation and do not care the result.*Notes:1. SSF send InitialDP to SCF and invoke the service logic.2. Applycharging and Connect are sent to SSP in parallel.3. Tdisconnect and ApplyChargingReport are sent to SCP in parallel.

*Notes:*

many operations are defined to perform information-flows-exchange between those entities to provide Intelligent Network services.***1. The provision of Detection Points (DPs) is required in the ISUP basic call handling in order to accessIN functionality and to allow IN service logic influence the processing of IN calls. The DetectionPoints (DPs) indicate Points in Calls (PICs) at which transfer of control can occur. If a DP isrecognized an operation from the SSF to the SCF will be sent. Thus the communication towards theSCP is performed.2. If a call is to be filtered and the "informationToSend" indicates announcement or tone, thenan ACM message will be sent to the preceding exchange; if the "informationToSend" indicates display information, REL message will be sent ACM: Address Complete MessageREL: Release Message

**This is another scenario of the interaction between INAP and ISUP, IP is attached to an assisting SSP, SCF inform the SRF using INAP, and then the SRF can play announcement to the user via ISUP.**Here we point out some potencial benefit with this interaction.*The concept of the softSSF is introduced which acts as an overlay between the IP telephony call control and the Intelligent Network layer provided by the INAP Service Switching Function (SSF) and the Service Control Function (SCF). This softSSF provides the necessary mapping between the SIP protocol state machine and the INAP Basic Call State Model (BCSM). SCN: Switched Circuit Network support IN call control of VoIP based on SIP call control

*{1} The terminating SIP Proxy Server receives an INVITE method. {2} If the necessary triggering criteria are met, the SCF is invoked and an INAP dialogue established between the softSSF and the SCF. {3} Instructions are received from the SCF on how the call is to be routed. {4} The SIP Proxy Server will route the call based on the instructions received by the service logic in the SCF. *The earlier IN architectue is proposed to be extended for the services in the convergent network. This will enable ease of migration of existing services in the converged networks.

RTP: Realtime Transport protol, Here SRF acts as a media gateway, all voice or multimedia information are transferred by SRF.Service Gateway acts as a signaling Gateway, which means it transfers signaling between IP network and PSTN.