KR100952828B1 - Processing method of softswitch failure in NGN - Google Patents

Abstract

The present invention relates to a method in which a service is not interrupted by switching to an alternative soft switch when a soft switch failure occurs in a next generation network.

In the next-generation network soft switch failure processing method according to the present invention, in the next-generation network in which the media gateway and the soft switch is interlocked to provide a general telephone service to the subscribers connected to the media gateway, the media gateway of the soft switch A failure detection step of detecting whether a failure occurs; A service switching request step, wherein the media gateway makes a service switching request to an alternative soft switch when a failure of the soft switch is detected; A service processing step of performing, by the substitute soft switch, a process for providing a general telephone service to the subscribers; The replacement softswitch includes a transition fact reporting step of notifying other softswitches of service transition for the subscribers.

Next Generation Network, Media Gateway, Soft Switch, Audit

Description

Processing method of softswitch failure in NGN}             

1 is a schematic configuration diagram of a next generation network;

2 is a configuration diagram of a general telephone service providing system in a next generation network;

3 is a timing diagram of signals transmitted between a soft switch and a media gateway;

4 is a flowchart illustrating a soft switch failure processing method according to an exemplary embodiment of the present invention.

The present invention relates to a next generation network, and more particularly, to a method of switching to an alternative soft switch so that service is not interrupted when a soft switch failure occurs.

The existing service network has a separate network for each service such as wired voice, wireless voice, and data. However, the next generation network is a network that supports transmission of traffic such as voice, video, fax, and data through the same link, and is a network in which separate networks such as PSTN network, cable network, wireless network, and IP network are integrated. Structures and network elements for next generation networks are defined for the purpose of integration and classification of functional layers.

Next-generation network elements include a softswitch 11 for call control as shown in FIG. 1, a protocol processing and media conversion for connection with the softswitch 11 by accommodating various subscriber stations. It stores various gateways 12, 13, 14, 18, application server 15 providing various services to these subscribers, packet delivery network 16 for transferring information between these elements, and resources necessary for various subscriber services. And providing a media server 17. The access gateway 12 connects the NGN subscriber station with the packet delivery network, and the trunking gateway 13 is connected with the public switched telephone network (PSTN) to connect the general public telephone subscriber station with the packet delivery network. The signaling gateway 14 is connected to the SS7 signal network, processes the SS7 standard protocol, and transmits and receives a signal with the public line switching network 19. The residential gateway 18 accommodates a small line and is installed in the home and connected to the packet network.

Currently, the international standardization organization is a control protocol between the soft switch 11, various gateways 12, 13, 14, and 18, and the media server 17. The media gateway control protocol (MGCP) and H.248 / Megaco Etc. are proposed.

In this next-generation network, a general telephone service is provided through interworking of a soft switch and a media gateway, for example, an access gateway and a trunking gateway. Soft switches in next-generation network services introduced by telecommunications companies generally accept large numbers of subscribers, and there are a plurality of media gateways that are directly connected to subscriber lines. If one soft switch fails, hundreds of thousands or millions There is a problem that the telephone service of subscribers is interrupted.

The present invention has been made to solve the above problems of the prior art, in the structure that the soft switch and the media gateway interworking for the general telephone service in the next-generation network, the media gateway monitors the normal operation of the soft switch, the soft switch In order to provide a failure handling method of switching to an alternative soft switch in case of a failure.

Soft switch failure processing method in the next-generation network according to the present invention for achieving the above object, in the next-generation network that provides a general telephone service to subscribers connected to the media gateway in conjunction with the media gateway,

A failure detection step of the media gateway detecting whether a failure of the soft switch occurs;

A service switching request step, wherein the media gateway makes a service switching request to an alternative soft switch when a failure of the soft switch is detected;

A service processing step of performing, by the substitute soft switch, a process for providing a general telephone service to the subscribers;

And wherein the replacement softswitch includes a switch fact reporting step of notifying other softswitches of service switching for the subscribers.

Hereinafter, a soft switch failure processing method in a next generation network according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

2 illustrates a general telephone service providing system in a next generation network. The system that provides subscribers with landline service includes soft switches (SSW1, SSW2, SSW3), media gateways (MGW1-1, MGW1-2, MGW2, MGW3) and subscriber databases.

The soft switches SSW1, SSW2, and SSW3 control call setup using the Megaco protocol when a subscriber requests a general telephone call connected to the media gateways MGW1-1, MGW1-2, MGW2, and MGW3. During call setup, control is performed throughout the telephone service such as collection digit analysis, routing, and subscriber service management, and commands media gateways (MGW1-1, MGW1-2, MGW2, MGW3) for processing. In addition, the media gateways MGW1-1, MGW1-2, MGW2, and MGW3 periodically send a status signal to inform the availability of the service.

Media Gateways (MGW1-1, MGW1-2, MGW2, MGW3) is a system connected to the physical subscriber line or trunk trunk line, detects the subscriber call view and directly executes the call processing command from the soft switch.

That is, the media gateways MGW1-1, MGW1-2, MGW2, and MGW3 report to the soft switches SSW1, SSW2, and SSW3 connected to the subscriber when the subscriber requests a call. The soft switches SSW1, SSW2, and SSW3 then instruct a dial tone command to proceed with call processing. The media gateways MGW1-1, MGW1-2, MGW2, and MGW3 send this dial tone command to the subscriber. When the subscriber presses a digit, the subscriber collects the digit and transmits the collected content to the soft switches SSW1, SSW2, and SSW3. Then, the soft switch (SSW1, SSW2, SSW3) finds the destination by using the collected digits, and transmits the information on the destination media gateway to the calling media gateway, and also transmits the information on the calling media gateway to the destination media gateway. In this case, the path between two media gateways is established in the packet network. The media gateway then monitors the end of the call and reports it to the softswitch when the call ends.

In addition, the media gateways MGW1-1, MGW1-2, MGW2, and MGW3 use a status signal (audit) periodically received from the softswitch to determine whether the softswitch is faulty, and even after a certain time has elapsed. If no audit is received, switch to the alternate softswitch.

Referring to Figure 2, the soft switch switching process will be described. It is assumed that the calling subscriber is connected to the first soft switch SSW1 through the first media gateway MGW1-1, and the called subscriber is connected to the first soft switch SSW1 through the second media gateway MGW1-2. do. In such a connection configuration, the calling subscriber and the called subscriber may connect the call paths under the control of the first soft switch SSW1 through the first media gateway MGW1-1 and the second media gateway MGW1-2, respectively. At this time, when a failure occurs in the first soft switch SSW1, the first media gateway MGW1-1 and the first media gateway MGW1-1 indicate that a failure of the first soft switch SSW1 has occurred. ) And request a switch to the second soft switch (SSW2) and the third soft switch (SSW3), which are alternative soft switches. Then, the second soft switch (SSW2) and the third soft switch (SSW3), which are requested to switch, update the subscriber database to start the control, and the first media gateway (MGW1-1) and the second media gateway (MGW1-) that requested the switch. It sends a transition result message to 2) and informs other softswitches to route itself to the call being sent to the subscribers.

Figure 3 shows a timing diagram of the status signal (audit) that the softswitch sends to the media gateway.

The soft switch SSW periodically transmits a status signal to the media gateway MGW, which is transmitted in a tint period. At this time, the media gateway MGW transmits a status request signal to the soft switch SSW if the status signal audit is not transmitted for a predetermined time tf, and then transmits the status request signal for a predetermined time tf. If there is no reply after that, soft switch switching request is made.

4 is a flowchart illustrating a soft switch failure processing method according to an exemplary embodiment of the present invention.

The media gateway detects whether a normal state signal audit is received from the soft switch within a predetermined time tf (tint <tf) (S41). This status signal (audit) is a message that tells the media gateway whether the service is available periodically (tint).                     

When the media gateway receives a normal status signal audit from the soft switch in step S41, the media gateway resets tf (S44) and repeats step S41.

If the normal state signal audit is not received from the soft switch in step S41, the media gateway transmits a status request signal to the soft switch and resets tf (S42). In operation S43, it is detected whether a normal state signal audit is received within a predetermined time tf.

The media gateway proceeds to step S44 when a normal state signal (audit) is received from the soft switch in step S43. If the normal state signal (audit) is not received from the soft switch in step S43, the media gateway transmits a service switch request signal to the replacement soft switch. (S45).

Subsequently, the replacement softswitch requested to switch performs processing related to initialization of subscriber data, in order to continuously provide a general telephone service to a failed softswitch subscriber (S46). After the processing is completed, the replacement softswitch transmits a success response message to the media gateway requesting the switching (S47), and notifies all other softswitches of the softswitch switching for the correct reception of the incoming call to the subscribers switched to them. (S48).

While the invention has been described above based on the preferred embodiments thereof, these embodiments are intended to illustrate rather than limit the invention. It will be apparent to those skilled in the art that various changes, modifications, or adjustments to the above embodiments can be made without departing from the spirit of the invention. Therefore, the protection scope of the present invention will be limited only by the appended claims, and should be construed as including all such changes, modifications or adjustments.

As described above, according to the present invention, by assigning an alternative soft switch to each media gateway and switching to an alternative soft switch immediately in case of failure of the main soft switch, it is possible to minimize service interruption of the subscriber and maintain a certain level of service quality at all times. There is this.

Claims (3)

In the soft switch failure processing method in the next-generation network that provides a general telephone service to subscribers connected to the media gateway by interworking the media gateway and soft switch, A failure detection step of the media gateway detecting whether a failure of the soft switch occurs; A service switching request step, wherein the media gateway makes a service switching request to an alternative soft switch when a failure of the soft switch is detected; A service processing step of performing, by the substitute soft switch, a process for providing a general telephone service to the subscribers; The replacement softswitch includes a transition fact reporting step of notifying other softswitches of service transition for the subscribers, The fault detection step, The media gateway transmitting a status request signal to the soft switch if the normal state signal of the soft switch is not received from the soft switch for a predetermined time; The media gateway includes recognizing a failure of the soft switch when the normal state signal of the soft switch is not received for a predetermined time after the state request signal is transmitted. . delete The method of claim 1, wherein the service conversion request step, And a plurality of media gateways interworking with the soft switch request service switching to different alternative soft switches.

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