KR100198466B1 - Transmitting call control method of vpn inter-calling in atm switching system - Google Patents

Abstract

The present invention relates to an intranet VPN call originating call control method in an ATM switching system, comprising: receiving an intranet call attempt sent by a subscriber; and receiving a private number plan identifier by a call setup message internal number plan identifier of the intranet call attempt. Determining whether to use a VPN call using the private number plan identifier, and extracting the VPN information of the calling subscriber from the VPN subscriber information table if the VPN subscriber is a VPN subscriber. Analyzing the VPN type with the VPN information, investigate whether outgoing calls are restricted when the network is inside the network and call restrictions of the internal call of the closed user group, processing the network outing when the network is outgoing, and performing call recovery processing on the other calls. And, if the call restriction investigation indicates that the call is restricted, call recovery processing is performed. Analyzing the class of the VPN group, extracting the local VPN recipient subscriber routing information if the local VPN is a local VPN, and extracting the local VPN recipient subscriber routing information if the VPN is a local VPN; Checking the result of extracting the VPN routing information and performing a call signal processing or a call recovery process according to the result of extracting the VPN routing information.

Description

Call Control Method of Intra-Personal Call (VPN) Network in ATM Switching System

The present invention relates to a method for controlling call origination in a VPN network in an ATM switching system. As the information society has developed into a high information society, each company can process a lot of information quickly. The regionalization and decentralization of the region has been required, and a way to communicate by grouping users across the wide area was required. At this time, ATM VPN was required to provide more economical and convenient functions as in the existing dedicated private network when communicating between users in the group. The most basic and important of the functions of the ATM VPN service is an intra-network service. The destination area is also included in his VPN private number plan, and the destination area also requests a call connection to the area subscribed to the VPN.

Therefore, in order to construct such a virtual private network, conventionally, most enterprises use a dedicated line to physically connect their enterprise network (PABX) over a geographically dispersed wide area, or a separate centralized service at the network level. A control and data processing dedicated system (SCP: Service Data Point) and a service processing linking system (SSP) are formed. When service demands occurred, they were passed to these systems (Bypass) so that the VPN service could be processed.

Such a conventional method separates the basic call / connection switching function from the switching system and the system performing the service control, and thus is efficient in terms of flexibility and adaptability due to the addition of a new service, but is accommodated in a single station switching system itself. Even in the case of a local VPN consisting only of a network, it is necessary to interwork with several network-level VPN service processing systems that perform VPN service processing, causing delays in service provision. It has the disadvantage of causing bottlenecks.

Therefore, in order to compensate for the above disadvantages, the present invention proposes the ITU-T DSS2 Q.2931 and the B-ISUP Q.2761 to Q.2764, which are proposed as point-to-point call / connection control signaling protocols as signaling protocols in VPN network call processing. The number plan indicator in the called party number or additional calling party number information element as a private number plan. It is proposed to handle the VPN network call, so that compatibility is maintained when interworking with other networks or other systems in the future, and efficient database configuration and VPN network code that can provide VPN network call service to wide area only by the function of ATM switching system itself. An outgoing call control algorithm is provided.

1 is a structural diagram of an ATM switching system,

2 is a block diagram of a call processing module and block in an ATM switching system;

3 is a block diagram of a call processing database in a VPN network in an ATM switching system according to an embodiment of the present invention,

4 is a flowchart illustrating a VPN network call origination call control algorithm in an ATM switching system according to an embodiment of the present invention.

In the virtual private network (VPN) network outgoing call control method in the ATM switching system provided by the present invention, when a subscriber registered in a VPN requests an intranet call attempt, an incoming VPN code is assigned to a called party number information element in a call establishment message. And a second step of confirming that the number plan identifier in the call setup message uses the private number plan identifier in the switch system receiving the first network initiation call attempt after the first step is transmitted to the exchange system. A third step of extracting the VPN information of the calling subscriber from the VPN subscriber information table if it is a VPN subscriber and determining whether the calling subscriber subscribes to the VPN if the VPN call uses the private number plan identifier; Analyzes the VPN type with the extracted VPN information from the network. The fourth step of examining call restriction of the call group; if the call is not restricted, if the call is not restricted; The fifth step of analyzing the configuration class, and performing call recovery processing if limited, and extracting the local VPN destination subscriber routing information if the local VPN is the local VPN, and the wide area VPN destination subscriber routing information if the local VPN is the local VPN. A sixth step of extracting and checking the result of extracting the VPN routing information extracted in the sixth step to perform general call signal processing if the VPN routing information extraction result is appropriate, and performing a call recovery process if not appropriate. It consists of.

According to the present invention, a VPN configuration class is classified into a home country and a wide area VPN for each VPN group. In the case of a home country VPN composed only of users in the corresponding ATM switching system, the subscriber service profile information in the corresponding switching system is used as in the CENTREX process. Thus, the B-ISDNE of the called party. By finding 164 number and linking with general call processing, it provides VPN network call service in such a way that performance is improved by minimizing traffic in network.

In case of a wide area VPN composed of users belonging to several ATM switching systems, the area code and prefix, which are routing information mapped to the VPN group identifier of the called party's VPN code, for the corresponding VPN group After determining the route to the destination exchange system in the same way as the general relay call processing, the B-ISDNE corresponding to the corresponding B-ISDNE is used by using the subscriber's VPN code and VPN group information delivered when the final destination exchange system turns out to be the incoming call. .164 Finds a number and provides network call service in connection with general call processing.

Hereinafter, with reference to the accompanying drawings will be described in detail the present invention.

1 is a structural diagram of an ATM switching system, FIG. 2 is a block diagram of a call processing module and a block in an ATM switching system, and FIG. 3 is a block diagram of a call processing database in a VPN network in an ATM switching system according to an embodiment of the present invention. 4 is a flowchart illustrating a VPN network call signaling control algorithm in an ATM switching system according to an embodiment of the present invention.

Referring to FIG. 1, the ATM switching system is a fully distributed high-speed large-capacity system, which is composed of a transmission network for transmitting user information and control information and a control network for controlling the same.

In this case, the transport network includes an Interconnection Switch Network Module (ISNM) 11, which is a switch network of an ATM Central Switching Subsystem (ACS) 10, and an Access Switch Network Module (ASNM) of an ATM Local Switching Subsystem (ALS) 20. And a switch network portion consisting of a Link Interface Module (LIM) 14 which performs link matching between the ASNM 22 and the ISNM 11, and a subscriber line matching and a relay line matching. It consists of a matching part 26 performing a trunk interface module (TIM) and a network synchronization part (NSP) 13 providing a system clock and a network, and the control network is a call processing part (CPP) performing call control. (24), NTP (Number Translation Part) to perform number translation process (25), Signaling Handler Part (SHP) to perform signal processing (23), Operation and Maintenance Part to perform system operation and maintenance (12).

In addition, communication of the ATM switching system having the above configuration is performed through the switch network portion of the basic transport network.

Referring to FIG. 2, a module and a block for call processing in an ATM switching system may include a user call control module (UCCM) 210 and a network call control module (NCCM). Network Call Control Module (220), Semi-Permanent Connection Control Module (SPCCM) 230, Link Resources Handling Module (LRHM) 240, Number Translation Module ( NTM: Number Translation Module (250) and VPN Service Control Module (VSCM).

The UCCM 210 is a module in charge of subscriber protocol matching and call control function using the Q.2931 protocol, and UPIF (User Protocol Interface) block 211 performing a matching function between the AAL and the Q.2931 call control layer. And a user protocol control (UPCF) block 212 for performing subscriber call processing by transmitting and receiving a Q.293 1 signal message from the UPIF 211 block, and a user data handling (UDHF) block for performing subscriber data processing. 213.

The NCCM 220 is a module that is responsible for relay line protocol matching and call control function based on the dms B-ISUP protocol, and performs NPIP (Network Protocol Interface) block 221 for performing a matching function between the MTP3 and the B-ISUP call control layer. And a Network Protocol Control (NPCF) block 222 for transmitting and receiving B-ISUP signal messages from the NPIF 221 block to perform relay line call processing, and a network da ta handling (NDHF) block for performing relay line data processing. 223).

The SPCCM 230 is a module that is responsible for operator registration and related connection setting and release processing for semi-permanent connection processing, and a semi-permanent point-to-poing virtual connection (SPVCF) block that performs a point-to-point semi-permanent connection control function. 231, a semi-permanent point-to-multipoint virtual connection (SMVCF) block 232 that performs a point-to-multipoint semi-permanent connection control function.

The LRHM 240 is a module that manages UNI and NNI links, internal switch link resources, and allocates and reclaims resources when a call occurs. The LRHM 240 performs a UNI Link resource management (ULRHF) block 241. , NNI Link Resources Handling (NLRHF) block 242 for performing NNI link resource management, Switch Link Resources Handling (SLRHF) block 243 for performing internal switch link resource management, Routing Control for performing routing control functions Block 244, and an RD Route Data Handling (RD HF) block 245 for performing route data processing.

The NTM 250 is a module for translating the subscriber's station number and the called party number translation and related translation data management functions. The NTM 250 performs a prefix translation, PFXTF (Prefix Translatin) block 251, and performs a called party translation. Called Number Translation (BLU) block 252, and NDHF (Number Data Handling) block 253 that performs number data processing.

The VSCM 260 is a module that is in charge of VPN service control and VPN service control data management functions. A VPN call control (VCCF) block 261 that performs a screening function for a VPN call using VPN subscriber information and a VPN subscriber profile A VPN Service Control (VSCF) block 262 for performing a VPN service control function using information, and a VPN Data Handling (VDHF) block 263 for performing VPN service related data processing.

Referring to FIG. 3, a database table for intra-VPN call processing in an ATM switching system includes a VPNRegInfo table 301, a VPNRouteInfo table 302, a VPNSv cInfo table 303, and a VPNUserInfo table 304. .

The fraudulent VPNRegInfo table (1) is a table that stores information about registered VPN group names, private number plans, VPN configuration classes, and billing methods for all VPN groups registered in the ATM switching system, and the VPNRouteInfo table (2). Is a table that stores routing information about the area code and the station number of the destination exchange, using the VPN group identifier of the registered VPN group-specific VPN code as an index, and the VPNSvcInfor table (3) is a VPN group number for users subscribed to a VPN. Is a table storing service profile information such as B-ISDN E.164 number, VPN call limit, and Closed User Group (CUG) using the VPN code as an index, and the VPNUserInfo table (4) joins a VPN. Table that stores VPN group number and VPN code information with index of E.164 number for users.

Referring to Figure 4, it can be seen that the VPN network call origination call control algorithm of the present invention, Figure 4a is a case of receiving a subscriber call setup message, Figure 4b is a case of receiving a relay call setup message, Referring to FIG. 4A, a subscriber registered in a VPN dials an incoming VPN code for a network call attempt, and a Calling Party Number information element in a Setup_ind message includes a calling party's public network number. The call setup message is transmitted to the ATM switching system to which the calling party is connected by assigning the B-ISDN E.164 number to the called party number information element, which is a dialed digit.

The UPIF of the ATM switching system that receives the call establishment message checks whether the numbering plan indicator (NPI) of the called party number information element in the call establishment message is a private numbering plan (PNP) and performs general call processing. Determining whether or not to perform a VPN call processing (402), and in case of a VPN call, the VCCF checks whether the calling subscriber subscribes to the VPN using the calling subscriber number as an index (403).

If it is determined that the subscriber is a VPN subscriber, the VPN group number and the VPN code of the calling subscriber are obtained from the VPNUserInfo table (404), and in the VSCF block, the VPN group number of the calling subscriber is indexed using the VPN group number of the calling subscriber in the VPNRegInfo table. The digit length and the VPN configuration class for the plan are found, and the service subscriber's service profile information is obtained from the VPNSvcInfo table by indexing the VPN group number and the VPN code of the calling party (404).

Then, the suitability is determined by comparing the received VPN code length with the PNP length for each VPN group, and the first digit value of the called party number (network number: 2-7, network number: 1, other: 0, 8, 9). VPN call type analysis (405) according to the present invention to investigate whether the outbound call is restricted or the call restriction in the case of CUG internal call in the case of the network call, and the network call processing (413) in the case of the network call. In other cases, call recovery processing 414 is performed.

The VPN configuration can be configured as a local area VPN in the ATM switching system or a global area VPN throughout the B-ISDN network according to the needs of the service subscribers. (407) In the case of a local VPN in the same ATM switching machine, since the called subscriber also exists in the ATM switching system to which the calling subscriber belongs, the E.164 number of the called subscriber is obtained by indexing the VPN group identifier and the called VPN code. 408, in case of an incoming call to another ATM switch as a wide area VPN, the length of the group identifier in the VPN group of the VPN group extracted from the VPNTRegInfo table is determined, and the corresponding VPN group identifier information in the VPN code of the called subscriber is indexed. From the VPNRouteInfo table, routing information mapped to the VPN group identifier is obtained (409).

According to the result of the routing information extraction process of the called subscriber, verify whether the VPN outgoing call processing is appropriate (410), and if necessary, deliver the necessary information for general call processing including VPN related information to UPCF to perform general outgoing call processing. Or, to provide the network call service by transmitting information including the corresponding VPN group number and the destination VPN code to the destination switching system so that the path to the called party switching system to which the called subscriber belongs to the NPCF is established (411). Call recovery processing according to the cause of failure is performed (412).

Referring to FIG. 4B, upon receiving the IAM-ind message (415), the PFXTF analyzes the call type according to the translation of the station number (416). Since the included VPN service information only needs to be transmitted to the called party, it performs the same as general relay call processing (417). In case of an incoming call, it is checked whether the additional calling party number information element is included (418) and additional calling subscriber information. If the element is not included, general incoming call processing is performed (419). If the additional calling party information element is included, it is checked whether the number plan identifier in the forwarded calling party number information element is set to private number plan. 420, if the number plan identifier is a private number plan, the VPN group expression in the destination VPN code and the subscriber party information element from the forwarded subscriber number information element. Taking out the E.164 number of the called party by using characters associated with 421 normal incoming call processing, and provides a network service naeho 419.

The virtual private network (VPN) network outgoing call control method in the ATM switching system of the present invention as described above allows a VPN to a wide area by setting only a number plan identifier in a called party number or an additional calling party number information element as a private number plan. By suggesting that the network call processing is possible, compatibility with other networks or other systems will be maintained later. In addition, it provides the virtual private network network call service more efficiently and the service providing ability of the ATM switching system is improved.

The present invention maintains a single numbering system internally for users across a wide area, and provides a simplified private numbering plan even when an international call or a long distance call is made in an internal network that is a communication between subscribers in the same virtual private network (VPN). It is an object of the present invention to provide a method for controlling a call originating in a VPN network in an ATM switching system capable of providing a VPN service within a wide area by using a network.

Claims (5)

When the subscriber registered in the VPN requests the in-network call attempt, after receiving the first VPN code in the called party number information element in the call establishment message, the first step is transmitted to the exchange system and the in-network call attempt of the first step is received. A second step of confirming that the number plan identifier in the call establishment message uses a private number plan identifier in a switch system; and if the VPN call uses the private number plan identifier as a result of the check in the second step, whether or not the originating subscriber joins the VPN If it is determined that the VPN subscriber is the VPN subscriber, extracting the VPN information of the calling subscriber from the VPN subscriber information table; Investigate the call restrictions of the user group internal call, handle the network call if it is network out, and call recovery if other calls And a fifth step of analyzing the class of the VPN group if the call is not restricted as a result of the call restriction investigation of the fourth step, and performing a call recovery process if the call is restricted. As a result of the rating analysis of the local VPN, the sixth step of extracting the local VPN recipient subscriber routing information, and the wide area VPN, extracting the local VPN recipient subscriber routing information, and confirming the extraction result of the VPN routing information extracted in the sixth step, If the VPN routing information extraction result is appropriate, general call processing is performed, and if it is not suitable, the seventh step of performing call recovery processing is a virtual private network (VPN) network call originating call control method in an ATM switching system. The method as claimed in claim 1, wherein the third step is a general call if the call is not using the private number plan identifier as a result of the second step. Method for outgoing call control of a virtual private network (VPN) network in an ATM switching system, characterized in that if the service is not a registered subscriber, call recovery processing is performed. A first step of receiving a relay call setup message, a second step of determining a call type from the call setup message received in the first step and checking whether an additional calling party subscriber information element is included in the incoming call; A third step of investigating whether the number plan identifier in the additional calling party information element is set to a private number plan when the result of the step 2 investigation includes the additional calling party information element, and the number in the additional calling party subscriber information element as a result of the third step. When the plan identifier is set to the private number plan, a virtual private network (VPN) outgoing call control in an ATM switching system, comprising the fourth step of extracting the called party number from the VPN information and then performing general incoming call processing. Way. 4. The method of claim 3, wherein the second step is to perform general relay call processing if the call type is a relay call. 4. The method of claim 3, wherein the second step or the third step does not include the additional search subscriber information element of the second search result, or the number plan identifier in the third search result additional calling party information element is private. Intranet call control method of a virtual private network (VPN) network in an ATM switching system, characterized in that a general incoming call processing is performed if the number plan is not used.