WO2011160365A1

WO2011160365A1 - System, method and soft switch for realizing t30 type fax soft switch full control in next generation network (ngn)

Info

Publication number: WO2011160365A1
Application number: PCT/CN2010/077868
Authority: WO
Inventors: 张明
Original assignee: 中兴通讯股份有限公司
Priority date: 2010-06-25
Filing date: 2010-10-19
Publication date: 2011-12-29
Also published as: CN101883112A; CN101883112B

Abstract

A system and a method for realizing T30 fax soft switch full control in Next Generation Network (NGN) are disclosed: after receiving a fax service request reported by a local media gateway, a soft switch transmits the service media which configured with a media type indication to the local media gateway and a remote media gateway; and the local media gateway and the remote media gateway transmit the received media to a chip in a bottom layer for switching the chip to a fax service state while judging that the transmitted media is fax service media according to the media type indication, and the fax service is processed after the local media gateway has a media negotiation with the remote media gateway. In which, through adding a coding keyword t into the media type of the local connection option to indicate the transmitted media service type corresponds to fax service, voice service, MODEM service separately. This solution can use Soft Switch (SS) to realize full controlled T30 type fax, and insure the chip in a bottom layer to switch the T30 fax in real time, and improve success ratio of the T30 type fax.

Description

System, method and softswitch for realizing full control of T30 fax softswitch in NGN

Technical field

The present invention relates to a fax technology in a next generation network, and more particularly to a system and method for implementing full control of the T30 fax softswitch in a next generation network. Background technique

The Next Generation Network (NGN) uses the Soft Switch (SS) technology that separates the service from the bearer media. The softswitch device operates the media gateway through the MGCP (Media Gateway Control Protocol) protocol. (Medium Gateway, MG). Among them, the so-called T30 fax full control is a service that the media gateway implements T30 fax under the control of the softswitch SS.

For the T30 fax service of the normal next-generation network NGN, the Session Initiation Protocol (SIP) and the H.248 protocol extend the attributes of the SDP (Session Description Protocol) media to implement the T30 fax service and voice service. The difference between control. However, the local media capability of the MGCP protocol is not delivered by the SDP, but is delivered through the local connection option attribute (LocalConnectionOption). Therefore, the difference control between the T30 fax service and the voice service cannot be realized at present.

For the H.248 protocol, the local T30 fax control provided by the softswitch SS is directly reflected in the SDP. An example is as follows:

V=0

c=IN IP4 $

m=audio $ RTP/AVP 0 8

a=fax

a=ptime:20

When the media gateway receives the SDP media voice stream with a=fax, it can be known that the voice media is used for faxing, instead of a voice call, and the fax state control is sent to implement the fax. For the SIP protocol, the media gateway prepares the fax media itself, and directly binds the attributes of the T30 media to the SDP media. This approach is similar to the H248 protocol.

However, in the Media Gateway Control Protocol MGCP, the local T30 fax media is delivered by the softswitch SS through the local connection option attribute (LocalConnectionOption). If the softswitch SS allows the gateway to pulse code modulation A law PCMA (Pulse Code Modulation a-law) and pulse code modulation μMU (Pulse Code Modulation μ-law) to implement T30 fax, it needs to be on the softswitch SS. Configure the fax media and deliver the fax media. The specific configuration information is: L: e: on, s: off, a: PCMU; PCMA, p: 20.

A screenshot of the softswitch SS configuration through the local connection option attribute is shown in Figure 1. In this case, according to this configuration, it cannot be expressed whether the media format is used for voice call or fax transmission, which may cause the media gateway. The underlying module can't identify whether it is a voice call or a fax. If the underlying module detects the fax signal and directly switches, it will not be affected by the SS control. The digital signal processor DSP (Digital Signal Processer) chip is miscut, not cut, early. Cut or cut late. Therefore, the existing practice will reduce the success rate of T30 fax.

At present, the mainstream practice for the MGCP protocol is that in the T30 state, the underlying layer is uncontrolled and switches itself. How to make the MGCP protocol gateway in the next-generation network NGN realize the SS full control T30 fax service becomes a problem to be solved.

Summary of the invention

The technical problem to be solved by the present invention is to provide a system, method and softswitch for realizing full control of the T30 fax softswitch in the next generation network, which is used for the fax service under the full control of the softswitch based on the media gateway control protocol MGCP.

In order to solve the above problem, the present invention proposes a system for implementing full control of T30 fax softswitch in a next generation network, including: softswitch and multiple media gateways under softswitch control, each media gateway and one or more faxes Connected by the media; the media gateway performs service transmission through a real-time transport protocol RTP media stream;

The softswitch is set to: after receiving the fax service request reported by the local media gateway, The local media gateway and the remote media gateway deliver the service medium configured with the media type indication; the local media gateway and the remote media gateway are configured to: when determining, according to the media type indication, that the delivered media is a fax service medium, Handing over the underlying chip to the fax service state processing, the softswitch is set to: indicate the service type of the delivered media by adding an encoding keyword t to the service type of the local connection option attribute, the encoding keyword The different values of t correspond to fax services, voice services, and modem services.

The softswitch is configured to: indicate a service type of the delivered media by adding an encoding keyword t to the service type of the local connection option attribute, the encoding key t only corresponding to the fax service.

The softswitch is configured to: deliver the media carrying the encoding keyword t for indicating the type of the media service to the local media gateway and the remote media gateway by using the MDCX message.

The present invention also provides a method for implementing full control of the T30 fax softswitch in a next generation network, including:

After receiving the fax service request reported by the local media gateway, the softswitch sends a service medium configured with the media type indication to the local media gateway and the remote media gateway;

When the local media gateway and the remote media gateway determine that the delivered media is a fax service media according to the media type indication, the intermediate chip switches to the fax service state processing, and the local media gateway and the remote media gateway perform media negotiation. After the fax business.

The softswitch indicates the service type of the delivered media by adding a coding key t to the service type of the local connection option attribute, and the different values of the coding key t correspond to the fax service, the voice service, and the modulation solution respectively. Adjust the business.

The softswitch indicates the service type of the delivered media by adding an encoding key t to the service type of the local connection option attribute, and the encoding key t corresponds only to the fax service.

The softswitch delivers the media carrying the coded keyword t for indicating the type of the media service to the local media gateway and the remote media gateway by using the MDCX message. The present invention also provides a softswitch for implementing T30 fax in a next-generation network, including a service request receiving module and a service media delivery module;

The service request receiving module is configured to: receive a fax service request reported by the local media gateway, and notify the service media delivery module;

The service media delivery module is configured to: after receiving the notification from the service request receiving module, deliver the service media configured with the media type indication to the local media gateway and the remote media gateway.

The service media delivery module is configured to: indicate a service type of the delivered media by adding an encoding keyword t to a service type of the local connection option attribute, where the different values of the encoded keyword t correspond to the fax respectively. Service, voice service, modem service.

The service media delivery module is configured to: indicate a service type of the delivered media by adding an encoding keyword t to a service type of the local connection option attribute, where the encoding keyword t corresponds to only the fax service.

The service media delivery module is configured to: the softswitch is configured to: deliver the media carrying the encoding keyword t for indicating the media service type to the local media gateway and the remote media gateway by modifying the connection command MDCX message .

The system and method for realizing the full control of the T30 fax softswitch of the invention can realize the full control T30 fax by the softswitch SS on the basis of the MGCP protocol, reliably guarantee the real-time switching of the T30 fax by the underlying chip, and improve the T30. Fax success rate.

BRIEF abstract

1 is a diagram showing an example of a configuration of a soft switch under the Media Gateway Control Protocol MGCP;

2 is a schematic structural diagram of a system for implementing full control of a T30 fax softswitch according to the present invention; FIG. 3 is a flowchart of implementing full control of a T30 fax softswitch;

FIG. 4 is a schematic diagram of a sub-flow of a media configured by a softswitch and a media gateway for determining a media type. Preferred embodiment of the invention

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be further described in detail with reference to the accompanying drawings.

In the next generation network (NGN), when the media gateway control protocol MGCP (MEDIA Gateway Control Protocol) is used, the softswitch SS configures and delivers related media resources to the media gateway, causing the media gateway to be based on the SS. The configuration cannot distinguish between a fax or a voice call, which can cause problems such as switching errors.

In the MGCP protocol, the local T30 fax media is delivered by the softswitch SS through the local connection option attribute (LocalConnectionOption). The present invention is extended to the local connection option attribute (LocalConnectionOption) of the SS configuration. After receiving the fax call reported by the media gateway through the MGCP protocol, the softswitch SS adds the service type parameter content to the local connection option attribute (for example, adding a coding key) The word is t) to implement the control application of the T30 media. The encoding keyword t can set the attribute value according to the service type to represent different services, for example: when t=0, the medium indicating the connection is voice; when t=l, it means fax; when t=2, Indicates the modem MODEM.

A specific application example, in the 5.2.10 local connection option of the Media Gateway Control Protocol released by China Telecom Group on December 31, 2003, the extension adds the encoding keyword ^ We can analyze the LocalConnectionOption parameter item. In the MGCP protocol, the service type parameter is not strictly defined and is not used at present, so the content of the service type parameter (the coding key is t) can be extended to implement the control application of the T30 medium.

For example, the following sends a PCMA or PCMU as an example. When the T30 fax is used, the softswitch SS sends L: e:on, s:off, a:PCMU; PCMA, p:20, t:l. =l; If it is MODEM media, then send L: e:on, a:PCMU; PCMA, p:20, t:2, configure t=2 at this time; if it is normal voice, configure t=0 or no Send configuration information.

The underlying chip (for example, DSP) of the media gateway receives the media configuration information delivered by the soft handover SS. If it is a fax service, the T30 fax media is delivered. Since the T30 fax media uses the voice RTP stream, the underlying chip of the media gateway (for example, DSP) needs to identify and distinguish the voice stream of the T30 and switch to the fax mode. In the invention, since the fax has been identified as t=l, the media gateway can realize the identification of the media stream of the T30 fax by the attribute value extension field delivered by the protocol, and can Differentiate voice and fax services to ensure business switching accuracy, thus achieving full SS control of voice and fax.

As shown in FIG. 2, a schematic diagram of a system for implementing full control of a T30 fax softswitch according to the present invention is shown, including a fax machine, a media gateway, and a softswitch. Each fax machine is connected to a softswitch through a corresponding media gateway, and is controlled by a softswitch. The local fax machine A1 is connected to the remote fax machine B1 through the local media gateway A2 and the remote media gateway B2, and the RTP (voice/video data stream real-time transmission protocol) is transmitted between the local media gateway A2 and the remote media gateway B2. ) Media streaming.

If the fax machine A1 picks up the phone and reports the fax signal, the media gateway A2 notifies the softswitch SS; when the SS receives the message requesting the fax service reported by the media gateway, the SS starts to prepare to configure the fax media, which includes the invention for expansion. The coded keyword is t, where t=l is represented as a fax service; the field description content contains the fax information, and the configured fax media is delivered to the media gateway.

A2; After receiving the media, the media gateway A2 judges the value of the extended attribute, and according to the result, determines whether it needs to switch to the fax mode. Here, if the analysis t = l is expressed as a facsimile service, the corresponding media is prepared and switched to the facsimile service state. In addition, the softswitch SS is also sent to the remote media gateway B2 to perform remote media negotiation, and the local media gateway A2 is notified to the negotiation result, so that the local end and the remote end negotiate the same, and both switch to the fax state. The normal sending and receiving of the fax service. The softswitch in the present invention includes a service request receiving module and a service media sending module. The service request receiving module is configured to: receive a fax service request reported by the local media gateway, and notify the service media delivery module; And after the notification of the service request receiving module is received, the service medium configured with the media type indication is delivered to the local media gateway and the remote media gateway.

As shown in Fig. 3, a flow chart for realizing the full control of the T30 fax softswitch in the present invention is given. Specific steps are as follows:

301: The fax connected to a media gateway needs to start the fax service, and the NTFY (a command in the MGCP protocol for the notification message) is reported to the softswitch SS to notify the softswitch SS to prepare the fax media.

302: The softswitch SS acknowledges the response 200 after receiving the message;

303: The fax media sent by the softswitch SS to the local media gateway, attached to the MDCX (MGCP) A command in the protocol, used to modify the connection, is sent in the message. The fax media sent is the T30 fax media configured after the local connection option attribute (LocalConnectionOption) is extended, with an extended field indicating that the voice is used for fax;

304: After receiving the media gateway, give a response 200 (SDP) to the softswitch SS;

In the above steps 303-304, the sub-process of the SS sent to the local media gateway and the local media gateway as shown in FIG. 4 can be subdivided as follows:

Sub-step 401, the softswitch SS configures the media segment used for the fax, and adds the attribute information of the keyword t, for example, t=l when faxing;

Sub-step 402: The fax media of this configuration is sent to the local media gateway with the MDCX message;

Sub-step 403: The local media gateway decodes the fax message segment, parses out the added keyword t, and judges the key segment t, and if t=l, it indicates that it is a fax medium;

Sub-step 404: The default service type of the local media is voice. If it is determined that the t value is not voice, the service type of the set media is fax. For example, if the voice is set to t=0, if the resolution is not equal to 0, then the service type is determined to be a fax, and of course, it can be directly determined according to t=l as a fax medium.

Sub-step 405: After the local media gateway determines the media type according to the keyword t, the media of the segment can be handed over to the DSP for processing according to the corresponding type.

305: The softswitch SS will receive the response, and send the MDCX message to the remote media gateway, and send the remote configuration media. The configuration media delivered here also has an extended attribute value t for indicating This media is a fax. The remote media gateway performs media negotiation with the local media gateway. If the negotiation succeeds, it starts to determine the attribute value of the media extension, and switches to the fax mode to prepare for receiving the fax;

306: The remote media gateway gives a response, notifying the softswitch that the SS successfully processes.

307: After obtaining the media negotiated by the remote media gateway, the SS sends the media with successful remote negotiation to the local media gateway through the MDCX message. Here, it is sent by the SDP message, so the attribute value a=fax can be brought over, and the local switch to the fax mode according to the attribute parameter of the fax, and the fax is started. 308: The local media gateway gives a response 200 (SDP) to notify the SS to successfully process. Start fax service processing.

309: After detecting the fax end event, the remote media gateway sends NTFY to the softswitch SS; 310: The softswitch SS gives the response 200, and ends.

Through the above steps, the T30 fax fully controlled by the softswitch SS can be realized based on the MGCP protocol, which reliably ensures the real-time switching of the T30 fax by the underlying chip, and improves the T30 fax success rate.

While the preferred embodiments of the present invention have been disclosed for purposes of illustration, those skilled in the art will recognize that various modifications, additions and substitutions are possible, and the scope of the invention should not be limited to the embodiments described above.

One of ordinary skill in the art will appreciate that all or a portion of the steps above may be accomplished by a program to instruct the associated hardware, such as a read-only memory, a magnetic disk, or an optical disk. Alternatively, all or part of the steps of the above embodiments may also be implemented using one or more integrated circuits. Correspondingly, each module/unit in the above embodiment may be implemented in the form of hardware or in the form of a software function module. The invention is not limited to any specific form of combination of hardware and software.

Industrial applicability

Claims

Claim

A system for implementing T30 fax softswitch full control in a next generation network, comprising: a softswitch and a plurality of media gateways under softswitch control, each media gateway being connected to one or more fax machines; said media The gateway transmits services through the real-time transport protocol RTP media stream;

The softswitch is configured to: after receiving the fax service request reported by the local media gateway, send the service medium configured with the media type indication to the local media gateway and the remote media gateway;

The local media gateway and the remote media gateway are configured to: when determining, according to the media type indication, that the delivered media is a fax service media, handing over the underlying chip to the fax service state processing,

2. The system of claim 1 wherein

The softswitch is configured to: indicate a service type of the delivered media by adding an encoding keyword t to the service type of the local connection option attribute, where the different values of the encoding key t correspond to the fax service, respectively. Service, modem service.

3. The system of claim 1 wherein

4. The system of claim 2 or 3, wherein

The softswitch is configured to: deliver the media carrying the encoding keyword t for indicating the type of media service to the local media gateway and the remote media gateway by modifying the connection command MDCX message.

A method for implementing full control of the T30 fax softswitch in a next-generation network, the method comprising: the softswitch transmitting the configured media to the local media gateway and the remote media gateway after receiving the fax service request reported by the local media gateway Type of business media indicated; and

6. The method of claim 5, wherein

Distributing a media type indication to the local media gateway and the remote media gateway in the softswitch In the step of the service medium, the softswitch indicates the service type of the delivered media by adding an encoding keyword t to the service type of the local connection option attribute, and the different values of the encoding keyword t correspond to the fax respectively. Service, voice service, modem service.

7. The method of claim 5, wherein

In the step of the softswitch transmitting the service medium configured with the media type indication to the local media gateway and the remote media gateway, the softswitch indicates the location by adding an encoding keyword t to the service type of the local connection option attribute. The service type of the delivered media, the coded keyword t only corresponds to the fax service.

8. The method according to claim 6 or 7, wherein

In the step of the softswitch sending the service medium with the media type indication to the local media gateway and the remote media gateway, the softswitch sends the code key for indicating the media service type by modifying the connection command MDCX message. The media of word t is given to the local media gateway and the remote media gateway.

A softswitch for implementing T30 fax in a next-generation network, comprising a service request receiving module and a service media delivery module; the service request receiving module is configured to: receive a fax service request reported by the local media gateway, and notify the Service media delivery module;

10. The softswitch of claim 9, wherein

11. The softswitch of claim 9, wherein

12. The softswitch of claim 9, wherein