KR101367225B1 - Method and apparatus for processing call between heterogeneous networks - Google Patents

Abstract

The present invention relates to a call processing technique between heterogeneous networks. To this end, the present invention relates to an LTE network terminal that must pass through at least four CGSs when an LTE network terminal calls a legacy network terminal in an environment in which a source and a receiving area are different. Unlike the conventional method described above, when a call connection request is received from the LTE network to the legacy network terminal, the destination exchange information of the legacy network terminal is received from the home location register, and a conversion gateway corresponding to the received destination exchange information is received. By transmitting the call connection request to the determined gateway, it is possible to minimize the cost incurred in the interworking of call processing between the LTE network and the legacy network. The deterioration of service quality can be effectively suppressed.

Description

Method and apparatus for call processing between heterogeneous manganese {METHOD AND APPARATUS FOR PROCESSING CALL BETWEEN HETEROGENEOUS NETWORKS}

The present invention relates to a call processing technique between heterogeneous networks, and more particularly, to provide a routing path of a legacy network optimized when an LTE network terminal calls a legacy network terminal (or a circuit network terminal) through an LTE network. The present invention relates to a heterogeneous manganese call processing method and apparatus therefor.

As is well known, a 3rd Generation Partnership Project (3GPP) mobile communication system based on a WCDMA (Wideband Code Division Multiple Access) radio access technology is widely deployed all over the world, and the first evolutionary stage of WCDMA HSDPA (High Speed Downlink Packet Access), which can be defined as a high-speed wireless communication system, provides a 3GPP mobile communication system with high-competitive wireless access technology in the mid-term future.

However, as the requirements and expectations of users and operators continue to increase and competition for development of wireless access technologies continues, there is a need to evolve new technologies in 3GPP mobile communication systems in order to gain competitiveness in the future. That is, a reduction in cost per bit, an increase in service availability, the use of a flexible frequency band, a simple structure and an open interface, and an appropriate power consumption of a UE are required. In addition, prevention of unnecessary latency at the network node and efficient use of network resources can also promote the technology evolution in 3GPP.

In 3GPP Release 8, a network architecture EPC (Evolved Packet Core) is described as one of mobile communication systems to satisfy the above-mentioned requirements. EPC is a set of network nodes for 3GPP LTE (Long Term Evolution) system. The EPC evolves the core network of the existing 3GPP system architecture to support Evolved-UMTS Terrestrial Radio Access Network (E-UTRAN), which is an evolved RAN, And has an efficient network structure that simplifies the network node. A wireless communication system including an EPC and an E-UTRAN may be referred to as an EPS (Evolved Packet System) and corresponds to an LTE mobile communication system currently being implemented and serviced in Korea.

Meanwhile, VoLTE service combining voice service with LTE has been developed and deployed. In such a mobile communication service environment, a technology for interworking call processing between heterogeneous networks, that is, between an LTE network and a legacy network (or a circuit network) is required. For example, when an LTE network terminal (or LTE network subscriber terminal) calls a legacy network terminal (or legacy network subscriber terminal) through an LTE network (call connection request), the LTE network terminal of the calling party is interworked with the LTE network. And call processing between the legacy network terminal of the called party.

In the conventional scheme, when the territories of the originating LTE network terminal and the terminating legacy network terminal are different from each other, a call is made to the HLR in response to routing of a plurality of CGSs (for example, four gateway exchanges), that is, IMGs. Gateway exchange conducting inquiries, originating relay exchange collecting data from each CGS of originating party, and receiving exchange relay exchange receiving data from originating relay exchange to CGS for routing to destination exchange It may be considered to proceed with the call processing through the communication path via the gateway exchange which routes the received data to the destination exchange.

Of course, when the territories of the LTE network terminal of the calling party and the legacy network terminal of the called party are the same area (eg, the metropolitan area), call processing will be performed through communication paths through three CGSs.

Republic of Korea Publication No. 10-2012-0014700, published 20 February 2012.

However, the above-described conventional method, in which the LTE network terminal calls through the legacy CGS in an environment where the calling and receiving areas are different from each other, has a relatively expensive cost. There are many routes through), which may have disadvantages from an economic point of view.

In addition, the conventional call processing scheme may have a disadvantage in that the service quality of the voice call is degraded due to a transmission delay caused by an increase in the call processing interval.

According to an aspect of the present invention, there is provided a method of receiving a call connection request for a legacy network terminal from an LTE network, receiving a destination exchange information of the legacy network terminal from a home location register in response to the call connection request; And determining a translation gateway corresponding to the destination exchange information received from the home location register, and transmitting the call connection request to the determined translation gateway.

Here, the destination exchange information may be signal point information of the destination exchange, and the destination exchange information may be included in an ATSI Resp message.

According to another aspect of the present invention, according to another aspect, when a call connection request for a legacy network terminal is received from the LTE network and a mapping table containing information of each transformation gateway corresponding to each exchange information of the legacy network, A destination network location acquiring unit for requesting destination exchange information of the legacy network terminal and a conversion gateway corresponding to the destination exchange information through mapping with the mapping table when the destination exchange information is received from the home location register; It provides a call processing device between heterogeneous networks including a route determination unit and a call processing unit for transmitting the call connection request to the determined translation gateway.

When the call connection request for the legacy network terminal is received from the LTE network, the present invention receives the destination exchange information of the legacy network terminal from the home location register, and determines the conversion gateway corresponding to the received destination exchange information. By transmitting a call connection request to the conversion gateway, the cost incurred in interworking with call processing between the LTE network and the legacy network can be restrained as much as possible, and the service delay of the voice call is reduced due to the transmission delay through shortening of the call processing interval. Can be suppressed effectively.

1 is a configuration diagram of a heterogeneous mobile communication mixed service system suitable for applying a heterogeneous call processing apparatus to the present invention;
2 is a conceptual schematic diagram illustrating a concept of interworking call processing between heterogeneous networks according to the present invention;
3 is a block diagram of a call processing device between heterogeneous networks according to the present invention;
Figure 4 is a flow chart illustrating the main process of interworking call processing between heterogeneous manganese in accordance with the present invention.

The technical gist of the present invention is different from the above-mentioned conventional scheme in which the LTE network terminal must go through a plurality of CGS when the LTE network terminal calls the legacy network terminal in an environment where the calling party and the receiving party are in different areas. When the call connection request for the terminal is received, the terminal receives the destination exchange information of the legacy network terminal from the home location register, determines the conversion gateway corresponding to the received destination exchange information, and transmits the call connection request to the determined conversion gateway. Therefore, the present invention can effectively solve the problems in the conventional manner by realizing the object through these technical means.

In the following description of the present invention, detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear. In addition, terms to be described below are terms defined in consideration of functions in the present invention, which may be changed according to intention or custom of a user, an operator, or the like. Therefore, the definition should be based on the technical idea described throughout this specification.

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

Referring to FIG. 1, a case in which a wideband code division multiple access (WCDMA) mobile communication system 102 is operated as a legacy network is illustrated. The legacy network is a long term evolution (LTE) mobile communication system (LTE). 106 illustrates a communication environment mixed with the exemplary embodiment, the present invention does not necessarily limit a WCDMA mobile communication system as a legacy network. For example, legacy networks such as other asynchronous mobile communication systems such as Global System for Mobile (GSM) or other synchronous mobile communication systems such as CDMA2000 may be mixed with the LTE mobile communication system 106.

First, the WCDMA mobile communication system 102 includes, for example, NodeB, Radio Network Controller (RNC), Mobile Switching Center / Visitor Location Register (MSC / VLR), Cellular Gateway Switch (CGS), and Serving General packet radio service Support Node (SGSN). ) Means a legacy network that may include a Gateway General Packet Radio Service Support Node (GGSN), etc., and is based on 3G for each terminal device belonging to the service area through NodeBs composed of multiple cells. Communication service (voice service, video service, multimedia service, etc.) can be provided. Here, the MSC / VLR in the WCDMA mobile communication system 102 stores visitor location information. The MSC / VLR receives subscriber profile information, authentication and location related data from the HSS 104, and performs switching control for voice communication. It can provide the function of.

To this end, the WCDMA mobile communication system 102 may access (connect) the IMS (IP Multimedia Subsystem) 112 through the circuit network 108 or access the IMS 112 through the IP network 110.

Next, the LTE mobile communication system 106 may include, for example, an eNodeB, a Mobility Management Entity (MME), a Serving Gateway (SGW), a PDN Gateway (PGW), a Policy & Charging Rule Function (PCRF), and the like. 4G-based communication services (voice service, video service, multimedia service, etc.) may be provided to each terminal device belonging to the service area through eNodeBs composed of a plurality of cells.

The IMS 112 may include a Call Session Control Function (CSCF) 1122, an Inter-working Media Gateway (IMG) 1124, a Home Subscriber Server (HSS) 1126, and the like.

First, the CSCF 1122 may include a call processing device between heterogeneous networks according to the present invention, performs call processing, and performs basic functions such as SIP (Session Initiation Protocol) based multimedia session control. As an infrastructure system, this CSCF 1122 handles subscriber registration, authentication, billing, triggering and routing per service, caller location lookup, compression and decompression of SIP messages, etc. Proxy_CSCF, Interogating-CSCF, Serving-CSCF And the like.

Next, the IMG 1124 converts signaling and media for interworking between the LTE mobile communication system 106 connected to the CSCF 1122 and the WCDMA mobile communication system 102 connected to the circuit network 108. Can provide functionality.

The HSS 1126 is a network node including a database including subscriber information of the wireless communication system for the WCDMA mobile communication system 102 and / or the LTE mobile communication system 106. Profile information, authentication and location related data can be stored.

In the example of FIG. 1, the WCDMA mobile communication system 102 and the LTE mobile communication system 106 operate the HSS 104 in an integrated manner, and the IMS 1124 operates the HSS 1126 in an independent manner. The WCDMA mobile communication system 102 and the LTE mobile communication system 106 may each independently operate the HSS. In addition, the WCDMA mobile communication system 102, the LTE mobile communication system 106, and the IMS 112 may operate one HSS in an integrated manner.

FIG. 2 is a conceptual diagram illustrating a concept of interworking call processing between heterogeneous networks according to the present invention. The mobile communication system for interworking call processing between heterogeneous networks includes CSCF 202, HLR 204, and a plurality of IMGs. 206/1 206 / n), multiple CGSs 208/1 208/4, multiple MSCs 210/1 210 / n, and the like.

Here, for the convenience of explanation and enhancement of explanation, it will be described below on the assumption that the LTE network terminal calls a legacy network (circuit network) terminal.

Referring to FIG. 2, the CSCF 202 refers to a component substantially the same as the CSCF 1122 illustrated in FIG. 1, and performs call processing or multimedia session control based on Session Initiation Protocol (SIP). It is an infrastructure system that performs basic functions for subscribers, and can provide functions such as subscriber registration, authentication, billing, triggering and routing for each service, incoming network location inquiry (query), and compression and decompression of SIP messages.

In addition, the CSCF 202 may include functional blocks as shown in FIG. 3 to provide call processing functionality between heterogeneous networks serviced in accordance with the present invention.

3 is a block diagram of a call processing device between heterogeneous networks according to the present invention. The heterogeneous call processing device according to the present invention includes a destination network position obtaining unit 202/1, a path determining unit 202/3, and mapping. And a table 202/5 and a call processor 202/7.

Referring to FIG. 3, the called network location obtaining unit 202/1 may call a legacy network terminal (or legacy network subscriber station) from an originating LTE network terminal (or LTE subscriber station) through an LTE network (not shown). When a connection request is received, the home location register 204 of the legacy network core (or legacy network core network area) is queried (inquired), i.e., legacy network location, through the IP network (not shown). It may provide a function such as requesting the destination exchange information of the terminal. Here, the request of the destination exchange information may be made through a MAP standard message.

Referring back to FIG. 2, the HLR 204 responds to a request for destination exchange information (a location query of a destination network) to a destination terminal in an Any Time Subscriber Interrogation (ATSI) Resp message for an IMS network (LTE network) originating call. The legacy network subscriber station inserts the destination exchange information registered in the CS location and transmits the information to the destination network location acquisition unit 202/1 in the CSCF 202 as a query response message. Here, the destination exchange information is, for example, signal point information of the destination exchange, and may be included in the ATSI Resp message as a point code expressed in hexa value. The ATSI Resp message is a MAP message defined in the 3GPP 29.002 standard. The ATSI Resp message is mainly used by the service nodes to inquire the subscriber related information to the HLR, and the ATSI query response message is ATSI_Redp.

Next, the route determining unit 202/3 responds to the incoming legacy network information obtaining unit 202/1 from the home location register 204 via the IP network in response to the incoming exchange information request (incoming network query). When the destination terminal information (eg, signal point information of the destination exchange) in which the network terminal registers location information is received, IMG for transmitting a call connection request received from the LTE network through mapping with the mapping table 202/5; Provide functionality such as determining a legacy network gateway switch (CGS). For this purpose, the route determination unit 202/3 in the CSCF 202 stores information on which IMG to route to the MSC.

For example, the destination exchange registered by the legacy network terminal of the called party is MSC # N 210 / n, and the media gateway connecting legacy network routing (or CS routing) to the CGS 208/4 is an IMG (206 / n). ), The route determining unit 202/3 determines the IMG 206 / n and the CGS () as a result of the mapping between the signal point information of the destination exchange 210 / n and the mapping table 202/5. 208/4).

For this purpose, the mapping table 202/5 contains information of each conversion gateway corresponding to each exchange information of the legacy network.

Then, the call processing unit 202/7 transmits a call connection request (data) to the IMG 206 / n of FIG. 2 (relaying call processing) in accordance with the decision made by the route determination unit 202/3. Can provide functionality.

Referring again to FIG. 2, the IMG 206 / n sends (routing) the call connection request sent from the CSCF 202 to the designated CGS 208/4. Here, the IMG 206 / n may provide a function for converting signaling and media for interworking between an LTE mobile communication system (LTE network) and a WCDMA mobile communication system (legacy network) connected to the CSCF 202. In this case, one or more IMGs may be installed per district (eg, metropolitan area, regional area, etc.), and one or more CGSs may be installed per district, which may be adaptively determined according to the number of LTE subscribers. . Here, the legacy network may be any one of 2G, 2.5G, and 3G mobile communication systems.

Next, the CGS 208/4 serves as a gateway connecting the LTE network and the legacy network such as WCDMA, and the circuit between the LTE mobile communication system and the WCDMA mobile communication system through the CSCF 202 connected to the legacy network. The CGS may be defined as a gateway MSC (Gateway MSC) or a gateway exchange.

Here, the CGS 208/4 sends an incoming query (or incoming inquiry) to the HLR 204 when a call connection request is received from the IMG 206 / n, and a response message to the incoming query from the HLR 204 is sent. When received, it provides functions such as routing call connection requests to the destination exchange (eg, 210 / n).

Next, a series of processes for providing call processing between heterogeneous networks using the mobile communication system to which the heterogeneous network call processing apparatus of the present invention having the above-described configuration is applied will be described in detail.

4 is a flowchart illustrating a main process of interworking call processing between heterogeneous networks according to the present invention.

Referring to FIG. 4, when a call connection request for a legacy network terminal (or legacy network subscriber station) is received from an originating LTE terminal (or LTE subscriber station) through an LTE network (step 402), the CSCF 202 may be used. The incoming network location obtaining unit 202/1 queries the home location register 204 of the legacy network core (or the legacy network core network area) the IP address of the legacy network terminal (called terminal) via the IP network. ), That is, the destination exchange information of the corresponding legacy network terminal is requested (step 404). Here, the location query of the called network is performed through the MAP standard message.

In response, the HLR 204, in response to the incoming exchange information request (received network location query), the destination exchange (Legacy network subscriber station) that the destination terminal (legacy network subscriber station) is located in the ATSI Resp message for the IMS network (LTE network) originating call. Information is inserted to generate a question and answer message, and the generated question and answer message is transmitted to the route determining unit 202/3 via the IP network (step 406).

Here, the destination exchange information of the corresponding legacy network terminal is, for example, the destination exchange (for example, signal point information of 210 / n) and is included in the ATSI Resp message as a point code expressed in hexa value. Can be.

Next, the route determination unit 202/3 receives the information from the LTE network through mapping between the destination exchange information of the legacy network terminal obtained from the home location register 204 and the mapping table 202/5 through the IP network. An IMG and a CGS (legacy gateway switch exchange) for sending the call connection request are determined (step 408).

As a result, the call processing unit 202/7 transmits the call connection request (data) received from the route determination unit 202/3 to the IMG (for example, 206 / n) (relay of call processing), and the IMG 206. / n) CS route the call connection request to the CGS (208/4) (step 410).

The CGS 208/4 then makes an incoming query (or incoming query) to the HLR 204, and when the response message to the incoming query is received from the HLR 204, the destination exchange (e.g. 210 / n) Route call connection requests.

Therefore, the voice call is connected between the LTE network terminal of the calling party and the legacy network terminal of the called party through interworking between the LTE network and the legacy network.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be construed as limiting the present invention. It will be readily apparent that such substitutions, modifications, and alterations are possible.

202: CSCF 204: HLR
206/1 206 / n: IMG 208/1 208/4: CGS
210/1 210 / n: MSC 202/1: Recipient network location acquisition unit
202/3: Path Determination Unit 202/5: Call Processing Unit
202/7: Mapping Table

Claims (6)

Receiving a call connection request from the LTE network to the legacy network terminal;
Receiving the destination exchange information of the legacy network terminal from a home location register in response to the call connection request;
Determining a conversion gateway corresponding to the destination exchange information received from the home location register;
Transmitting the call connection request to the determined translation gateway
Call processing method of heterogeneous manganese comprising a. The method of claim 1,
The destination exchange information,
Signal point information of the destination exchange
Method of handling call of heterogeneous manganese. 3. The method of claim 2,
The destination exchange information,
Included in Any Time Subscriber Interrogation (ATSI) Resp messages
Method of handling call of heterogeneous manganese. A mapping table that contains information of each conversion gateway corresponding to each exchange information of the legacy network;
When the call connection request is received from the LTE network to the legacy network terminal, the destination network location acquisition unit for requesting the destination switch information of the legacy network terminal to the home location register,
A path determining unit for determining a conversion gateway corresponding to the destination exchange information through mapping with the mapping table when the destination exchange information is received from the home location register;
Call processing unit for transmitting the call connection request to the determined conversion gateway
Heterogeneous manganese call processing apparatus comprising a. 5. The method of claim 4,
The destination exchange information,
Signal point information of the destination exchange
Call processing device of heterogeneous manganese. The method of claim 5, wherein
The destination exchange information,
Included in Any Time Subscriber Interrogation (ATSI) Resp messages
Call processing device of heterogeneous manganese.

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