KR100485213B1 - Signaling gateway transport and sharing method traffic of application server therein - Google Patents

Abstract

The present invention relates to a signal gateway device and a method for distributing application server traffic of the signal gateway device. The signal gateway device according to the present invention includes: a signal gateway device protocol processor for detecting a signal received from a NIF and a neighboring signal gateway device (SIGTRAN) node and classifying the signal into a control signal or a data signal; Search for an application server suitable for a signal received through the signal gateway device protocol processing unit, and store information included in the received signal in an application server information store and an application server process information store, or previously stored according to the received signal; An application server manager for changing a state of an application server process; And a message transceiving unit for retrieving an active application server process serving the application server retrieved by the application server management process and transmitting it to the adjacent signal gateway device node. Accordingly, the present invention can efficiently distribute traffic between SCN networks and packet networks, and can be applied to Voice over ATM (VoATM) and Voice over IP (VoIP) systems that enable voice services at low prices.

Description

SIGNALING GATEWAY TRANSPORT AND SHARING METHOD TRAFFIC OF APPLICATION SERVER THEREIN}

The present invention relates to a method for distributing traffic of an application server (hereinafter referred to as an AS) of a signal gateway device, and more particularly, to a signal gateway device (SGP) in a signaling gateway (SIGTRAN). Alternatively, the present invention relates to a method for distributing traffic of an AS to each active ASP when the Internet Protocol Server Process (IPSP) communicates with several active application server protocols (ASPs) serving one AS.

SIGTRAN is a protocol for transmitting a Switched Circuit Network (SCN) signaling message to a packet network. The SIGTRAN includes a higher layer protocol and a stream control transmission protocol (SCTP).

The upper layer protocol is a protocol supporting a service required by a specific SCN signaling application protocol, and includes signaling systems No. 7 message transfer part 3 (MTP3) user adaptation layer (M3UA), SS7 MTP2 user adaptation layer (M2UA), and SUA (SS7). SCCP-User Adaptation Layer) and IUA (ISDN Q.921-User Adaptation Layer).

SCTP is a new transport protocol that exists in layers such as Transmission Control Protocol (TCP) and User Datagram Protocol (UDP). It is similar to TCP in that it uses connection-oriented mechanisms and provides reliable data transfer. Do. However, unlike TCP, it provides adequate functionality for signal transmission and provides enhanced security against external attacks, such as anonymous blind denial of service attacks and blind masquerade attacks. By using the multi-stream function, data can be transmitted, so that data transmission is more flexible than TCP in case of data loss.

In addition, SCTP supports multi-homing, bundling / unbundling, and ordered / unordered transmissions.

1 is a diagram illustrating a configuration of a general next generation network.

As shown in FIG. 1, a Next Generation Network (NGN) has a media gateway (MG) 110 connected to a packet network 100, and the SCN network 120 includes a signal gateway ( It is connected to the MG 110 through a Signaling Gateway (SG) 130 and a Softswitch 140.

SCN network 120 includes a public telephone network (Public Switched Telephone Network) and an intelligent network (Intelligent Network) that is a conventional telephone network. The SG 130 serves to transfer a signaling message between the SCN network 120 and the packet network 100, and is equipped with an SS7 (Signaling System No. 7) protocol stack and a SIGTRAN. The SIGTRAN protocol is used for communication between the SG 130 and the soft switch 140.

The SG 130 communicates with the plurality of soft switches 140 when the active ASPs to communicate with each other exist in the plurality of soft switches 140, and one soft switch when the active ASPs with communication exist in one soft switch. Communicate with the switch.

Soft switch 140 is a device for transmitting and receiving SS7 messages from the SG (130) and controls the MG (110) to perform a call connection, SIGTRAN, MEGACO (Media Gateway Control), BICC (Bearer Independent Call Control) (Or Session Initiation Protocol for Telephones (SIP-T)) and ISUP (ISDN User Part). The MEGACO protocol is used for communication between the soft switch 140 and the MG 110, and the call is established and released between the two soft switches 140 using the BICC or the SIP-T protocol.

The MG 110 converts the voice medium of the SCN network 120 into a packet form used in the packet network 100. The packet network 100 accumulates the information transmitted from the calling party, divides the information into packets of a certain size, and adds the address of the receiver to transmit the information in packet units.

However, such a conventional SG 130 does not have a specific method of distributing traffic for one AS to a plurality of active ASPs, and thus, efficient traffic distribution is not possible.

Accordingly, the present invention is to solve the problems of the prior art, the signal gateway device to select the appropriate active ASP from among a plurality of active ASPs serving one AS in the SG and to use for traffic distribution, and application server traffic of the signal gateway device It is an object to provide a dispensing method.

The signal gateway device according to the characteristics of the present invention for achieving the technical problem is located between the Switched Circuit Network (SCN) network and the packet network, and transmits and receives data by converting signals between each other using a Nodal Interworking Function (NIF) Signaling Gateway (Signaling Gateway) device to perform,

A signal gateway device protocol processor for detecting a signal received from the NIF and an adjacent signaling gateway (SIGTRAN) node and classifying the signal into a control signal or a data signal; Search for an application server suitable for a signal received through the signal gateway device protocol processing unit, and store information included in the received signal in an application server information store and an application server process information store, or previously stored according to the received signal; An application server manager for changing a state of an application server process; And a message transceiving unit for retrieving an active application server process serving the application server retrieved by the application server management process and transmitting it to the adjacent signal gateway device node.

The signal gateway device protocol processing unit initializes the signal gateway device if the classified control signal is an initialization processing signal.

The application server manager,

If the classified control signal is an application server process message, the information of the message is stored in the application server information store or the application server process information store according to the type of the message, and the classified data signal is received from the NIF. If the signal is a search for an application server suitable for the signal, if the classified control signal is a Heart Beat (Heart Beat) message notifying the state change of the application server process (Application) stored in the application server information store and the application server process information store Change the state of a server process.

Wherein the application server information store includes the application server status, application server mode, application server index, application server process status, routing key and recalled number information,

The application server process information store includes the application server process flag, Assoc ID, application server process status and recalled information.

In addition, in the traffic distribution method of the application server according to an aspect of the present invention, the signal gateway process in the signaling gateway device that performs signal transmission between the switched circuit network (SCN) and the packet network to activate the traffic of the application server As a method of distributing to server processes,

a) detecting a signal received from the NIF and an adjacent signal gateway device node and classifying the signal into a control signal or a data signal; b) if the received detected signal is a control signal and an application server process message, registering information of the message in an application server information store or an application server process information store according to the type of message; c) changing the state of an application server or application server process stored in the application server information store or application server process information store if the received detected signal is a control signal and a heartbeat message that changes the state of the application server process; d) searching for the corresponding application server in the application server information store and searching for an active application server process serving the corresponding application server if the received detected signal is a data signal received from the NIF; e) transmitting a message of the received signal to the adjacent signal gateway device node via the retrieved active application server process if there is only one active application server process retrieved in step d); And f) if there are two or more active application server processes retrieved in step d), searching for active application server processes again within the CIC (Circuit Identification Code) range of the received signal to detect adjacent signal gateways through the retrieved active application server processes. Sending a message of the received signal to a device node.

In step f),

If there is one active application server process found in the CIC range, the message of the received signal is transmitted through the corresponding active application server process, and if there are two or more active application server processes found in the CIC range, the first active application is found. Select a server process in turn to send a message of the received signal.

At this time, when there are two or more active application server processes searched in the CIC range, the last active application server process is selected to send a message of the received signal, and when another message is transmitted, the first active application server process is sequentially turned on. Select and transmit a message of the received signal.

Further, in step b),

If the received detected signal is a control signal and an initialization message, the signal gateway device is initialized.

The method may further include discarding a message of the received signal if there is no active application server process found in step d).

Further, in step b),

If the application server process message is an up / down message or an active / inactive message, register the information of the message in the application server information store and the application server process information store, and if the application server process message is a routing key, the application server information store. The information of the message is registered in.

In this case, the routing key includes a destination point code (DPC), an origination point code (OCC), and a circuit identification code (CIC) range.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings the most preferred embodiment that can be easily carried out by those of ordinary skill in the art as follows.

2 illustrates a configuration of a signal gateway processor (SGP) according to an embodiment of the present invention, in which a process represents a logical unit of a protocol, and interprocess communication is performed asynchronously through a signal.

As shown in FIG. 2, the SGP according to an embodiment of the present invention includes a SIGTRAN protocol processing process 210, a Nodal Interworking Function (NIF) 220, an adjacent SIGTRAN node 230, an AS management process 240, and a message. A transmit / receive process 250.

The NIF 220 converts an MTP3 (Message Transfer Part 3) message into an M3UA message or an M3UA message into an MTP3 message in order to transmit and receive a message with the SIGTRAN protocol processing process 210. That is, the NIF 220 converts the MTP3 message into an M3UA message and delivers it to the SIGTRAN protocol processing process 210, and converts the M3UA message delivered from the SIGTRAN protocol processing process 210 into an MTP3 message and delivers it to MTP3.

The SIGTRAN protocol processing process 210 monitors the signals received from the NIF 220 and the adjacent SIGTRAN nodes 230, and processes the signals according to the control signal or data signal, respectively, when the signals are received.

That is, if the signal received by the SIGTRAN protocol processing process 210 is an initialization processing signal which is a control signal, the SIGTRAN protocol processing process 210 initializes SIGTRAN, and if the ASP message is an ASP information store or an AS information store according to the ASP message type, respectively. Register at In addition, if the received message is a heartbeat message that is a control signal and notifies the ASP status change, the ASP status information is changed in the AS information store and the ASP information store through the AS management process 240.

On the other hand, if the signal received by the SIGTRAN protocol processing process 210 is a data signal received from the NIF 201, the AS management process 240 searches for an appropriate AS, and retrieves an active ASP serving the AS to send and receive a message. Transmit to neighbor SIGTRAN node 230 via 250. At this time, the data signal received from the neighboring SIGTRAN node 230 is transmitted to the SCN network according to the SGP routing key, the detailed description thereof will be omitted.

Hereinafter, the traffic distribution method of the signal gateway according to an embodiment of the present invention will be described in detail.

3 shows a processing sequence of the SIGTRAN protocol according to an embodiment of the present invention.

As shown in FIG. 3, the SIGTRAN protocol processing process 210 monitors the received signal (S300) to determine whether the received signal is a control signal or a data signal from the NIF 220 (S310). As a result of the determination, if the received signal is a control signal, it is checked whether it is a SIGTRAN initialization message (S311), and if it is a SIGTRAN initialization message, SIGTRAN initialization processing is performed (S312). If the control signal received in step S311 is not a SIGTRAN initialization message, it is checked whether it is an ASP related message or a heartbeat message (S313). If the check result is an ASP related message, the message type is determined (S314), and if the ASP UP / ASP DOWN message or an ASP active / inactive message is registered, the information is registered in the AS information store and the ASP information store, respectively ( S315). If the ASP message type is a routing key, this information is registered in the AS information store (S316). In this case, the routing key includes a destination point code (DPC), an origination point code (OCC), and a circuit identification code (CIC) range.

If it is determined in step S313 that the control signal received is a heartbeat message, it is determined whether the ASP state change information is included (S317) and according to the included state change information of each AS and ASP stored in the AS information place and the ASP information store. The state is changed (S318).

In addition, if it is determined in step S313 that the ASP related message or the heartbeat message is not processed according to the message content (S319).

On the other hand, if the signal received by the SIGTRAN protocol processing process 210 is a data signal from the NIF 220, the corresponding AS is retrieved from the AS information store (S321), and if there is a corresponding AS (S322), an active service serving the AS. Search the ASP to check the number of active ASPs (S323 ~ 324). In this case, if there is no active ASP, but there is an inactive ASP, the message is stored for a predetermined period (Recovery timer T (r)), and if there is no inactive ASP, the message is discarded (S325). If there is one active ASP, a message is transmitted to the neighboring SIGTRAN node 230 where this ASP exists (S326). In addition, if there are two or more active ASPs, the CIC value of the received SS7 message is compared with the CIC value of the active ASP registered in the AS information store to check whether there is a corresponding active ASP and check the number of active ASPs (S327 ~ 328). ). As a result, if the number of active ASPs is one, a message is transmitted to an adjacent SIGTRAN node 230 in which this ASP exists (S329). If two or more active ASPs are selected, the first active ASP is selected (S330).

At this time, the ASP index of the AS information store and the number of calls are increased so that the next SS7 message is selected as the second active ASP instead of this active ASP. This sequential increment is used up to the end of the ASP index, which in turn selects the first active ASP. In addition, the number of times the AS information store is called is a value stored to know the number of messages sent through the corresponding ASP.

On the other hand, if there is no AS corresponding to the received data signal from the NIF 220 in step S322 above (step S325).

4 illustrates a configuration of information stored in an AS information store according to an embodiment of the present invention.

As shown in FIG. 4, the information stored in the AS information store according to an embodiment of the present invention may include the AS state 401, the AS mode 402, the ASP index 403, the ASP state 404, and the routing key 405. ) And the number of times called 406.

The AS state 401 indicates a state of the current AS, and is classified into four states of active, inactive, down, and pending. The down state indicates that the AS is in an unavailable state, in which all ASPs serving the AS are in the down state. Initially, the AS is in a down state, even when the AS is removed from the shape. An inactive state is when an AS is available but application traffic is not active, where at least one of the plurality of ASPs associated with the AS is inactive and there is no active ASP. In addition, the active state is when the AS is available and application traffic is active, and at least one of the plurality of ASPs associated with the AS is active.

In addition, the pending state refers to a case where the last active ASP of the corresponding AS has transitioned to an inactive or down state. In this state, the recovery timer T (r) starts and all input signal messages are stored in the SGP. If one of the ASPs becomes active before T (r) expires, the AS becomes active and all stored messages are sent to the ASP. However, if the recovery time T (r) expires before the ASP becomes active and there is no alternative in the SGP, the SGP stops storing the message and discards all previously stored messages. At this time, if at least one ASP is inactive, the AS is inactive, and if there is no inactive ASP, the AS is down.

The AS mode 402 represents a traffic processing mode of the AS, and is divided into three modes of override, loadshare, and broadcast. The traffic mode type parameter in the ASP active message indicates that the traffic processing mode is used for a particular ASP. In addition, if the SGP determines that the mode configured for the current AS does not support the mode of the ASP active message or is incompatible, the SGP responds to the ASP with an error message.

If the AS mode is override mode, the SGP forwards all traffic for the AS to the ASP that sent the ASP active message. At this point, the previously active ASP is considered inactive and should no longer receive traffic from the SGP, and the SGP (or IPSP) sends an alert message (Alternate ASP_Active notify) to the previously active ASP and no longer sends traffic to this ASP. Do not transmit. In addition, the ASP that receives this notification should consider its state as inactive.

On the other hand, in the AS in the load share mode, all ASPs in which the SGP (or IPSP) is active are selected in order from the first to transmit the traffic. In this case, in order to distribute the traffic to the active ASP in the SGP, the present invention first compares the CIC value of the SS7 message with the registered CIC value in the AS, and if there are several active ASPs within the CIC range, the SGP is the first active ASP. Select from to send traffic in order. In addition, for broadcast mode AS, all currently active ASPs will receive the same message.

ASP index 403 represents ASPs that have registered routing keys to service an AS. If the mode of the AS is loadshare and there are multiple active ASPs, then the routing key 405 retrieves the ASPs that fall within the CIC range, and when there are multiple active ASPs that satisfy this condition, the first active ASP in the ASP index. It will be selected from to receive traffic from SGP. At this time, the number of calls of the corresponding ASP stored in the AS information store is increased by one.

The ASP state 404 is divided into active, inactive, and down states, and this value can be changed according to a heartbeat message periodically transmitted and received between the SGP and the ASP.

The routing key 405 is a value determined by the DPC / OPC / CIC range value, and is a value received from the soft switch 140 and stored.

On the other hand, Figure 5 shows the configuration of information stored in the ASP information store according to an embodiment of the present invention.

As shown in FIG. 5, an ASP information store according to an embodiment of the present invention stores an ASP flag 501, an Assoc ID 502, an ASP state 503, and a call count 504. The ASP flag 501 is a value indicating whether a value is stored in this ASP information store, and the Assoc ID 502 is a value for identifying an association of SIGTRAN SCTP. In addition, the ASP state 503 is a value representing the state of the ASP, which may have a value of Active / Inactive / Down, and the number of calls 504 indicates the number of times the SGP has sent traffic to this ASP.

The present invention described above is not limited to the above-described embodiments and the accompanying drawings, and various substitutions, modifications, and changes are possible in the technical field of the present invention without departing from the technical spirit of the present invention. It will be clear to those of ordinary knowledge.

As described above, the present invention proposes a method of multiplexing AS traffic using a load sharing scheme in a SIGTRAN of a signal gateway, thereby enabling active management of a state change of the ASP to efficiently manage traffic. In addition, the AS traffic multiplexing method according to the present invention can be applied to a VoATM and VoIP system interworking an SCN network and a packet network.

1 is a diagram illustrating a configuration of a general next generation network.

2 is a block diagram of a signal gateway process (SGP) according to an embodiment of the present invention.

3 is a flowchart of SS7 message distribution in a signal gateway according to an embodiment of the present invention.

4 is a diagram illustrating a configuration of an AS information store according to an embodiment of the present invention.

5 is a diagram showing the configuration of an ASP information store according to an embodiment of the present invention.

*** Description of symbols for the main parts of the drawings

210: Signal Gateway Device Protocol Processing Process

220: Nodal Interworking Function (NIF)

230: adjacent signal gateway device node

240: application server management process

250: message sending and receiving process

Claims (12)

In the Signaling Gateway (Signaling Gateway) device located between the Switched Circuit Network (SCN) network and the packet network to perform signal transmission, A signal gateway device protocol processor for detecting a signal received from the NIF and an adjacent signaling gateway (SIGTRAN) node and classifying the signal into a control signal or a data signal; Search for an application server suitable for a signal received through the signal gateway device protocol processing unit, and store information included in the received signal in an application server information store and an application server process information store, or previously stored according to the received signal; An application server manager for changing a state of an application server process; And And a message transceiving unit for retrieving an active application server process serving the application server retrieved by the application server management process and transmitting it to the adjacent signal gateway device node. Signal Gateway Device. The method of claim 1, The signal gateway device protocol processing unit initializes the signal gateway device when the classified control signal is an initialization processing signal. Signal Gateway Device. The method of claim 1, The application server manager, If the classified control signal is an application server process message, store the information of the message in the application server information store or the application server process information store according to the type of the message, If the classified data signal is a data signal received from the NIF, search for an application server suitable for the signal; If the classified control signal is a Heart Beat message for notifying the state change of the application server process (Heart Beat) to change the state of the application server process stored in the application server information store and the application server process information store Signal Gateway Device. The method of claim 1, The application server information store, The application server status, application server mode, application server index, application server process status, routing key and recalled information. Signal Gateway Device. The method of claim 1, The application server process information store, Including the application server process flag, an Assoc ID, an application server process state, and recalled information. Signal Gateway Device. In a signaling gateway device for signaling between a switched circuit network (SCN) network and a packet network, a method for distributing traffic of an application server to an active application server process in a signaling gateway device, a) detecting a signal received from the NIF and an adjacent signal gateway device node and classifying the signal into a control signal or a data signal; b) if the received detected signal is a control signal and an application server process message, registering information of the message in an application server information store or an application server process information store according to the type of message; c) changing the state of an application server or application server process stored in the application server information store or application server process information store if the received detected signal is a control signal and a heartbeat message that changes the state of the application server process; d) searching for the corresponding application server in the application server information store and searching for an active application server process serving the corresponding application server if the received detected signal is a data signal received from the NIF; e) transmitting a message of the received signal to the adjacent signal gateway device node via the retrieved active application server process if there is only one active application server process retrieved in step d); And f) if there are two or more active application server processes retrieved in step d), search for an active application server process again within the CIC (Circuit Identification Code) range of the received signal, and the adjacent signal gateway device through the retrieved active application server process. Sending a message of the received signal to a node Application server traffic distribution method of the signal gateway comprising a. The method of claim 6, In step f), If there is one active application server process found in the CIC range, the message of the received signal is transmitted through the corresponding active application server process, If there are two or more active application server processes found in the CIC range, the first active application server process is selected in order to transmit a message of the received signal. How application server traffic is distributed by the signaling gateway. The method of claim 7, wherein When there are two or more active application server processes retrieved in the CIC range, the last active application server process is selected to send a message of the received signal, and when another message is sent, the first active application server process is sequentially selected again. Transmitting a message of the received signal How application server traffic is distributed by the signaling gateway. The method of claim 6, In step b), And if the received detected signal is a control signal and an initialization message, initializing the signal gateway device. The method of claim 6, Discarding the message of the received signal if there is no active application server process retrieved in step d) Application server traffic distribution method of the signal gateway further comprising. The method of claim 6, In step b), If the application server process message is an up / down message or an active / inactive message, register the information of the message in the application server information store and the application server process information store, If the application server process message is a routing key, registering the information of the message in the application server information store; How application server traffic is distributed by the signaling gateway. The method of claim 11, The routing key includes a destination point code (DPC), an origination point code (OCC), and a circuit identification code (CIC) range value. How application server traffic is distributed by the signaling gateway.