KR20060006347A - Apparatus and method of routing in softswitch system - Google Patents

Abstract

The present invention relates to a routing device and method for a soft switch capable of satisfying both the ITU and ANSI recommendations. To this end, the present invention relates to a soft switch and a routing database including a routing database that stores routing information for all kinds of calls. A routing device and method for performing routing by using the present invention are proposed.

Softswitch, service control point (SCP), SCP routing,

Description

Routing device and method of soft switch system {APPARATUS AND METHOD OF ROUTING IN SOFTSWITCH SYSTEM}             

1 is a soft switch system and a network configuration to which the present invention can be applied.

2 illustrates a routing interface of a softswitch system.

3 is an internal configuration diagram of a soft switch system.

4 is a schematic diagram of a routing database used for routing in a softswitch;

The present invention relates to a routing apparatus and method for a softswitch system, and more particularly, to a routing apparatus and method for supporting integrated routing for circuit data and packet data.

In addition to the existing Public Switching Telecommunication Network (PSTN) as well as packet-based Next Generation Network (NGN) integrating IP (Internet Protocol) and wireless networks into one, Interest in new network technologies and advanced next-generation call control protocols, such as Session Initiation Protocol (SIP) or Media Gateway Control Protocol (MGCP), have enabled IP telephony, soft telephony, and soft private branch eXchange (PBX). IP-based terminals and access gateways, integrated access equipment, media gateways, DSL (digital subscriber line) access multiplexers, and network hardware, including cable modem termination systems. To deliver fully integrated IP-based voice / data networks to business and business subscribers Large broadband services can be deployed.

However, the conventional exchange could only support Point Code and Subsystem Number (PC & SSN) routing or only GT routing. That is, the conventional exchanger does not accept both the ANSI and ITU recommendations, and has a problem that SCP routing is different according to the operator and the recommendation.

Accordingly, an object of the present invention is to provide a routing device and a routing method for enabling SCP routing integrating operators and respective recommended standards in order to solve these problems.

The present invention to achieve the above object; A routing device of a softswitch system for routing all incoming calls, the routing device comprising: a database storing routing information for transmitting a received call; We propose a routing device comprising a call controller for obtaining routing information.

In addition, the present invention to achieve the above object; A routing method of a soft switch system for routing all received calls, the method comprising: determining whether the received call is an intelligent network call when an arbitrary call is received; and for the call determined as the intelligent network call in the first process. And a second step of determining the type of routing requested by the call, and a third step of retrieving the routing information for each item storing the routing information of the type according to the determination result of the second step. We propose a routing method characterized by the above-mentioned.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In describing the present invention, if it is determined that the detailed description of the related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

It will be appreciated that the present invention described below is applied to a soft switch system used in Next Generation Network (NGN).

Softswitch is a new S / W-based switching technology that separates call logic and access, allowing service providers to deliver massive amounts of existing voice traffic over packet-based voice networks. In order to provide the voice service provided by the PSTN in the packet network, H.323, SIP, BICC, MGCP, MEGACO / H.248 that enables the voice service in the packet network while satisfying various requirements for interworking with the PSTN. SoftSwitch's innovative architecture, which simultaneously accepts protocols and the like, demonstrates the ability to dramatically change the way we communicate over the public network.

Softswitch architecture consists of a media gateway and a media gateway controller. Service providers and carriers are replacing Class 5 voice switches with softswitches. Class 5 switches are large and expensive voice exchangers that are installed and used in central telephone stations around the world. It receives a dial-up telephone signal from the user and connects the circuit of the telephone exchange period. SoftSwitch separates the Class 5 switching architecture into a gateway and a gateway controller. The media gateway transforms circuit alternating or voice traffic into packet-based traffic. The media gateway controller, called a call agent or softswitch, controls the switch and traffic functions.

Soft Switch, which is a bridge between circuit and packet networks and provides call control and routing functions for voice traffic, uses a standard interface in a gateway system for interworking between different networks to separate control functions. A kind of gateway control system, sometimes referred to as a media gateway controller, call servers or call agents, depending on a standardization organization or a manufacturer.

Founded in May 1999 to improve global softswitch interoperability and promote Internet-based multimedia communications and application growth, the International Softswitch Consortium (ISC) has established softswitches in various media gateways, signaling gateways, IP phones, and integrated IADs. Access device) to provide call access service, perform exchange call control functions such as tone, announcement and address translation, call routing in the network based on signaling information and customer DB information, It is linked with network operation management system, billing and subscriber management system, and service control point of intelligent network, and is defined as a software platform that provides an open API (Open Application Programming Interface) so that third parties can develop new services.

ISC currently provides the following definitions and criteria for network elements identified as softswitches. According to the definition and criteria of the ISC, softswitches are based on the ability to control access services to media gateways and / or pure IP terminations, the ability to select the processing that can be granted to a single call, and signaling and customer database information. Routing for calls within the network, having the ability to transfer call control to other network elements, interfaces and support with management functions such as bad billing, MGCP, MEGACO, SIP, SS7, complex programming language (CPL), Support for multiple protocols including H.323, Q.931 / Q.2931, DiffServ, resource reservation protocol (RSVP), multiprotocol label switching (MPLS), realtime transport protocol (RTP), remote copy (RCP), and 802.1p Compatible with / interoperable with ITU, IETF, FRF (Frame Relay Forum), ATM Forum, and IEEE standards.

First, the soft switch will be described with reference to the drawings.

1 is a configuration diagram of a soft switch and a network to which the present invention can be applied.

As shown in FIG. 1, the soft switch 100 is a service control point (SCP 1 or SCP) through a signal transfer point (STP) (STP 1 or STP 2) 132 or 134 of the No7 network 130. SCP 2) (150 or 152) may be connected. In addition, the soft switch 100 may be connected to an application server (AS) 160 through an Internet Protocol (IP) network 140. Since the present invention relates to the No7 network, description of the IP network will be omitted.

First, the components of the soft switch 100 will be described. The soft switch 100 includes an IH 102, a Call Control Function / Service Switching Function (CCF / SSF) 104, an SCP Routing DB 106, an Integrated Services Digital Networks (ISDN) processing unit ( 108), ISUP (ISDN User Part) processing unit 110, Plain Old Telephone Service (POTS) 112, Session Initiation Protocol (SIP) processing unit 114, H.323 processing unit 116, Transaction Capabilities Application Part 118), Signaling Connection Control Part (SCCP) 120, Message Transfer Part (MTP) 122, and local SCP 124.

The MTP 122, SCCP 120, and TCAP 118 of the softswitch 100 are used for the transmission of the call, the call control unit 104 is used for the processing of the call, the ISDN processing unit 108, the ISUP processing unit 110 ), POTS processing unit 112, SIP processing unit 114 and H.323 processing unit 116 is used to support the protocols of the various networks that are integrated. The SCP routing database 106 stores the routing information that the softswitch 100 needs to send a call to the SCP. The SCP here also includes a local SCP 124 that is directly connected to the softswitch 100 via a network, in addition to SCP 1 or SCP 2 (150 or 152) shown in FIG. In FIG. 1, a local SCP 124 is shown in the softswitch 100.

The soft switch 100 of FIG. 1 interworks with an STP (Signalling Transfer Point) 132 or 134 of the No7 network for intelligent network call processing.

In general, an intelligent network has a service control point (SCP) that has network-level service control logic, a service management system (SMS) that manages data required for service provision, and accesses to an SCP through an existing exchange. It consists of Service Switching Point (SSP) which adds the function to do so and No.7 common line signal network connecting them.

Of these intelligent network components, when used as a single station exchange, the SSP provides users with access to the network and provides the necessary switching function for intelligent network call connection. To this end, the SSP has the ability to detect intelligent network services, the ability to communicate with other physical media such as SCP, and the ability to respond to commands received from other physical entities. Functionally, the SSP may include a Call Control Function (CCF) and a Service Switching Function (SSF).                     

SCP has service logic program and data necessary for intelligent network service processing and is connected to SSP, IP, etc. through signaling network. Multiple SCPs can have the same type of service logic program or data for improved service reliability or load sharing between SCPs.

The intelligent network separates the basic call processing function and the service control function from the exchange in the existing telephone network, and allows SCP to execute the service control function. When the SSP detects and informs SCP of call processing events necessary to provide the intelligent network service, the SCP executes the corresponding intelligent network service logic and instructs the SSP to call processing. In this structure, when the new service is introduced into the network, the basic call processing part does not need to be changed, so the service can be added quickly without any additional cost. For this purpose, SCP has a structure that can interact with various network elements, and controls services with various intelligent network service logic programs (SLP). The basic components of SCP are service logic execution environment and service logic program. Service logic program is executed on service logic execution environment. The service logic program is a service application program that realizes an intelligent network service under the control of the service logic execution environment.

In Figure 1 it can be seen that the call control unit 104 of the soft switch corresponds to the SSP. The call control unit 104 of the soft switch 100 routes to interoperate with a Service Control Point (SCP 1 or SCP 2) of a Public Switched Telephone Network (PSTN) network that controls services of intelligent network call processing. That is, when the call control unit 104 receives a call, the call control unit 104 searches the SCP routing database 106 to obtain routing information about the received call, and transmits the received call to the corresponding SCP according to the obtained information.

In the present invention, the call control unit 104 should be able to provide SCP routing that can support both GT (Global Title) and PC & SSN (Point Code & SubSystem Number) scheme.

2 illustrates a routing interface of a softswitch system.

In FIG. 2, GT (Global Title) routing 201 and PC & SSN (Point Code and SubSystem Number) routing 203 are shown. In the SCP routing, the softswitch 100 converts the GTS value into SCCP (Signalling) when the STP (STP 1 or STP 2) 132 or 134 translates the GT (Global Title) to the GTS (Global Title String). It should be included in the Connection Control Part) message and signaled to the STP (132 or 134) .If the STP (STP 1 or STP 2) 132 or 134 is routed to the PC & SSN, it will be sent to the SCCP message as the PC and SSN value of the SCP. It should be configured and signaled to STP 2 (134). Both GT routing and PC & SSN routing are accomplished by the call control unit 104 searching the SCP routing database 106 to obtain routing information. Call transmission through the TCAP 118, the SCCP 120 and the MTP 122 is not directly related to the present invention, so a description thereof will be omitted.

As shown in FIG. 2, routing information on how the softswitch 100 should route each intelligent network service exists in the SCP routing database 106 inside the softswitch 100. Routing information used for the routing of calls, stored in the SCP routing database 106, is sent to the operator before the call controller 104 queries the call processing message of the intelligent network service to SCP (SCP 1 or SCP 2) 150 or 152. It can be set by or determined at the time of call processing progress. As described above, the SCP routing database enabling both GT routing and PC & SSN routing will be described with reference to the drawings.

3 is an internal configuration diagram of a soft switch system.

SCP routing database 106 includes itemized databases of Trigger DB 210, Service DB 212, SCPGroup DB 214, and SCP DB 216.

When the trigger DB 210 of these item-specific databases 210 to 216 receives a routing information retrieval request for an arbitrary call from the call controller 104, the trigger DB 210 determines whether the call is an intelligent network call, and when the call is an intelligent network call. The routing information search for the call is performed. That is, the trigger DB 210 includes information for determining whether an arbitrary call is an intelligent network call. The service DB 212 includes information for determining where the service requested by the call is located. SCPGroup DB 214 determines whether to perform GT routing or PC & SSN routing for the call. That is, SCP DB 214 includes information for determining what routing to perform for the call. SCP DB 216 includes PC & SSN routing information.

In the present invention, routing information retrieval in the SCP routing database 106 is performed sequentially.                     

As a result of the determination in the trigger DB 210, the call determined as the intelligent network call is determined in the service DB 212 where the service requested by the call exists. In this case, the location where the service requested by the call exists may be an AS 160 in addition to the local SCP 124 and the remote SCP (SCP 1 or SCP 2) 150 or 152, but in the following description, the IP network Routing to AS 160 via 140 is omitted and only SCP routing is described. However, the description thereof is omitted, and the soft switch 100 proposed by the present invention can perform routing to the AS 160 as well.

If the search result of the service DB 212 determines that the service requested by the call is located in the local SCP 124, information indicating this is transmitted to the call control unit 104. The call controller 104 routes the call to the local SCP 124. On the other hand, if a search result for the service DB 212 determines that the service requested by the call is located in a remote SCP (SCP 1 or SCP 2) 150 or 152, a search for the SCPGroup DB 214 is performed.

SCPGroup DB 214 determines whether the call is a call requesting GT routing for a call determined to be present in a remote SCP (SCP 1 or SCP 2) 150 or 152, or a call requesting PC & SSN routing. Determine the cognition. Since the STP (STP 1 or STP 2) 132 or 134 obtains the address of the SCP according to the GT routing, the SCPGroup DB 214 sends the call to the corresponding STP (STP 1 or STP 2) 132 or 134. The information to be transmitted is transmitted to the call control unit 104. If the call is a call requesting PC & SSN routing, SCPGroup DB 214 allows the PC & SSN routing information retrieval for the call to be made in SCP DB 216.

SCP DB 216 retrieves the PC & SSN routing information of the call and transmits it to the call controller 104.

On the other hand, the connection between each item database (210 to 216) can be made using an index that specifies the next item-specific database.

The SCP routing database 106 will be described in more detail with reference to the drawings below.

4 is a schematic diagram of an SCP routing database used for routing in a softswitch.

In FIG. 4, a primary key of the trigger DB 210 is a trigger name value, and an index for associating with a service DB 212, which is a database for each item, is a service key value. The trigger DB 210 checks Trigger Criteria suitable for intelligent network processing by using a Trigger Name value, which is a primary key value, for a call for which routing information is requested from the call controller 104. If the call is determined to be an intelligent network call, the trigger DB 210 requests the service DB 212 to search for the call using a ServiceKey value that is an index value.

The primary key of the Service DB 212 is a ServiceKey value, and the index for associating with the SCPGroup DB 214 which is the next item-specific database is a SCPGroupIndex value. Service DB 212 uses the ServiceKey value to determine whether the service requested by the call is located in local SCP 124 or remote SCP (SCP 1 or SCP 2) 150 or 152. If the call is a request for a service located in the local SCP 124, the Service DB 212 transmits the corresponding information to the call control unit 104, and terminates the routing information search. On the other hand, if the call is a call requesting a service located in a remote SCP (SCP 1 or SCP 2) 150 or 152, the Service DB 212 uses the SCPGroupIndex value to perform a search for the call using the SCPGroup DB 214. Ask.

SCPGroup DB 214 determines whether the call is a request for GT routing or a call requesting PC & SSN routing for a call that is requested to retrieve routing information. If the call is a call requesting GT routing, the SCPGroup DB 214 transmits information about the STP (STP 1 or STP 2) 132 or 134 to perform the GTS translation to the call controller 104 and the routing information. Terminate the search. In this case, the softswitch 100 constructs an SCCP message destined for the remote SCP (SCP 1 or SCP 2) 150 or 152 using the GTInformation value of the SCPGroup DB 214. On the other hand, if the call is a call requesting PC & SSN routing, SCPGroup DB 214 requests SCP DB 216 to retrieve PC & SSN routing information for the call.

The primary key of SCP DB 216 is the SCPName value. SCP DB 216 retrieves the PC & SSN information for the call requested to retrieve the routing information, and transmits the result to the call controller 104. In this case, the softswitch 100 retrieves a particular SCP from the SCPMap of the SCP DB 216 if it is a PC SSN Routing and uses the PC and SSN values of that SCP to remote SCP (SCP 1 or SCP 2) (150 or 152). It will construct a SCCP message to the.

Table 1 below shows important values and contents of each item database of the SCP routing database 106.

DB Atribute Item Content RouteService Application server (AS) Service exists in Application Local SCP Service exists in Local SCP Remote SCP Present in service Remote SCP RoutingInd GTRouting Routed to GT PCSSNRouting Routed to PC & SSN GTInformation GTS Global Title String TT Translation Type GTI Global Title Indicator

The values of SCP DB 216 determined in the call processing progress state are GTS and SCP state information. The GTS of SCPGroup DB 214 may be configured as a called party or calling party or set by an operator. In addition, SCP state information of the SCP of the DB 216 may be determined by the No7 state messages (N_PCStateInd, N_StateInd) received from the SCP through the No7 network.

The Service Key of the SCP Routing Database 106 is defined in the ITU Recommendations and becomes the distinguishing element of each intelligent network service. On the other hand, in the case of ANSI, the element that distinguishes each intelligent network service is SSN. Therefore, the SCP routing database model of the present invention, which allows the use of both Service Key and SSN, may enable the distinction of intelligent network services in any recommendation.

On the other hand, using the soft switch 100 proposed in the present invention can obtain the effect of load balancing, the reason is as follows. SCPMap of SCPGroup DB 214 can group one or more SCPs and manage load share values for grouped SCPs. For example, if the status information of an SCP managed by SCPMap is Inactive, the SCP is excluded from routing information and the remaining SCPs can be used for routing by dividing Load Share value.

Specifically, PC & SSN routing that enables load balancing is described in detail. When SCP 1 (150) and SCP 2 (152) exist in SCPMap of SCPGroup DB (214) as shown in Table 2 below, the Load Share value is respectively If the SCP 1 (150) is INACTIVE, but the SCP 1 (150) is INACTIVE, the remaining SCP, SCP 2 (152), will have 100% of the Load Share value at run time. Routed to SCP 2 (152). Afterwards, when SCP 1 (150) transitions to ACTIVE, routing will be restored to the initial 40% and 60% values. The sum of Load Share values of SCPs present in SCPMap of SCPGroup DB 214 is 100 and expressed as a percentage.

SCPNAME LOADVALUE LOADVALUE (RT) ACCESS SCP1 40% 0% INACTIVE SCP2 60% 100% ACTIVE

By applying the present invention, it is possible to design a softswitch system capable of satisfying both the requirements of the recommending organization and the operator for SCP routing, thereby allowing the operator to flexibly operate the softswitch system.

In addition, the ability to group information about SCPs in the SCP routing database allows load balancing.

Claims (9)

A routing device in a softswitch system for routing all incoming calls, A routing database that stores routing information for transmitting incoming calls; And a call controller which, upon receiving any call, retrieves the database to obtain routing information for transmitting the received call and to process the call according to the routing information. The routing device of claim 1, wherein the routing database includes at least one item-specific database that stores routing information according to a type of a call requested to be searched by the call controller. 3. The routing device of claim 2, wherein the routing database includes a first itemized database storing information for determining whether the call is an intelligent network call. The routing device of claim 2, wherein the routing database comprises a second itemized database storing information for determining a location of a service requested by the call. The method of claim 4, wherein the second item-specific database stores information for determining whether the service requested by the call is located in a local SCP (Service Control Point), a remote SCP, or an AS (Application Server). Routing device. The method of claim 2, wherein the routing database includes information for determining whether a call requesting a service located in a remote SCP is a call requesting GT routing or a call requesting PC (Point Code) & SSN (SubSystem Number) routing. A routing device further comprising a third itemized database for storing. 3. The apparatus of claim 2, wherein the routing database further comprises a fourth itemized database that stores routing information for calls requesting remote SCP PC (Point Code) and SSN (SubSystem Number) routing. The routing device of claim 1, wherein the routing database groups and stores SCP information to be routed, and allows the SCP to be routed to be selected according to the state of each grouped SCP. A routing method of a softswitch system for routing all incoming calls, If a call is received, determining whether the received call is an intelligent network call; A second step of determining the type of routing requested by the call with respect to the call determined as the intelligent network call in the first step; And a third step of searching for an item-specific database storing corresponding type of routing information and acquiring the corresponding routing information according to the determination result of the second step.

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