WO2011160345A1

WO2011160345A1 - Method and system for transmitting out-of-band dual-tone multi-frequency signal on media surface

Info

Publication number: WO2011160345A1
Application number: PCT/CN2010/077157
Authority: WO
Inventors: 朱广亮
Original assignee: 中兴通讯股份有限公司
Priority date: 2010-06-22
Filing date: 2010-09-20
Publication date: 2011-12-29
Also published as: CN101860630B; CN101860630A

Abstract

The present invention discloses a method and a system for transmitting an out-of-band dual-tone multi-frequency signal on a media surface, and the method includes: in a Bearer Independent Call Control (BICC) network, a Mobile Switching center (MSC) sends Dual-Tone Multi-Frequency (DTMF) capability negotiation information of a Media Gateway (MGW) to a USS through a control channel; said USS disposes said DTMF capability negotiation information and sends a DTMF capability negotiation result to said MGW through the control channel; when the capability negotiation succeeds, said USS and said MGW establish a media channel according to said DTMF capability negotiation result and transmit the DTMF signal on the out-of-band through said media channel. The method and the system for transmitting the out-of-band dual-tone multi-frequency signal can implement the out-of-band transmission of the DTMF signal in the BICC network.

Description

Transmission method and system for external dual-tone multi-frequency signal in media plane

Technical field

The invention relates to a transmission method and system for a medium-band out-of-band dual-tone multi-frequency signal in a BICC network. Background technique

The Dual Tone Multi Frequency (DTMF) signal is a kind of user signaling between a telephone and a switch in a telephone system, and is usually used to transmit a called number. Before using a dual tone multi-frequency signal, a series of intermittent pulses are used in the telephone system to transmit the called number, called a pulse dial. Pulse dialing requires an operator in the telecommunications office to manually complete the long distance connection. The dual tone multi-frequency signal was invented by Bayer Laboratories for the purpose of automatically completing long distance calls.

The dual tone multi-frequency dial keypad is a 4 x 4 matrix, with each row representing a low frequency and each column representing a high frequency. Each time a button is pressed, a combination of high frequency and low frequency sinusoidal signals is sent, such as 'Γ is equivalent to 697 and 1209 Hz (Ηζ). The switch can decode these frequency combinations and determine the corresponding buttons.

The DTMF codec converts keystrokes or digital information into a two-tone signal and transmits it during encoding, and detects the presence of keystrokes or digital information in the received DTMF signal during decoding. A DTMF signal consists of a superposition of audio signals at two frequencies. The frequency of these two audio signals comes from two sets of pre-assigned frequency groups: the line frequency group or the column frequency group. Each pair of such audio signals uniquely represents a number or symbol. There are usually 16 buttons in the phone, including 10 number keys 0 ~ 9 and 6 function keys *, #, A, B, C, D. Since there are generally 8 different single audio signals in accordance with the combination principle. Therefore, there are 8 kinds of frequencies that can be used, so it is called multi-frequency, and because it is arbitrarily extracted from high and low frequencies, it is combined to encode, so it is called "8 in 2". technology. According to the CCITT Advisory Committee's recommendations, there are 8 kinds of frequencies used in the world, such as 697Hz, 770Hz, 852Hz, 941Hz, 1209Hz, 1336Hz, 1477Hz and 1633Hz. With these eight frequencies, 16 different combinations can be formed to represent 16 different numbers or function keys.

DTMF is also widely used in interactive controls such as language menus, language mail, telephone banking, and various Interactive Voice Response (IRR) processes. In the process of switching a communication network from a traditional circuit-switched network to an IP-borne broadband network,

The bearing of the DTMF signal also changes. Similar to traditional circuit domain transmission, in IP network, DTMF (In Band DTMF) is transmitted in-band, and DTMF audio data packets are directly encapsulated and transmitted by RTP protocol without any codec conversion. In addition, RFC2833 (RFC2833 is a specification file) defines another method for out-band DTMF (Out of Band DTMF). The media gateway detects DTMF and re-encodes the package using the RTP packet. Audio packet. The RFC2833 out-of-band numbering mode can support the transmission and reception of multiple variable length button information.

In addition to the above two ways of transmitting DTMF signals on the media side, in the broadband network, the DTMF signals can also be directly transmitted by signaling. The standard BICC protocol uses APM messages to transmit DTMF information directly on the signaling plane. When transmitting the DTMF signal on the BICC signaling plane, each time a button is transmitted, in actual applications, it is troublesome to send and receive multiple buttons.

In the 3GPP R4 network, the Nc interface (signaling plane) uses the Bearer Independent Call Control Protocol (BICC), and the IP Bearer Control Protocol (IPBCP) is used in the 3GPP R4 network based on the IP bearer network. Bearer Control Protocol) As the control plane protocol for the Nb interface (media side), the standard IPBCP protocol defines some negotiation rules for the basic capabilities required for media transmission, but does not provide a control negotiation method for the transmission of out-of-band key information on the Nb interface. Summary of the invention

The technical problem to be solved by the present invention is to provide a method and system for transmitting out-of-band dual-tone multi-frequency signals in a medium to realize OFDM transmission of DTMF signals in the media plane of a BICC network.

To solve the above technical problem, the present invention provides a method for implementing multi-tone dual-frequency signal transmission of a medium out-of-band medium, the method comprising:

In a bearer-independent call control protocol (BICC) network, a mobile switching center (MSC) transmits a dual tone multi-frequency (DTMF) capability negotiation information of a media gateway (MGW) to a USS through a control channel;

The USS processes the DTMF capability negotiation information, and sends the DTMF capability negotiation result to the MGW through the control channel; When the capability negotiation succeeds, the USS establishes a media channel with the MGW according to the DTMF capability negotiation result, and transmits the DTMF signal out-of-band through the media channel.

The step of the MSC transmitting the DTMF capability negotiation information of the MGW to the USS by using the control channel includes:

The MSC sends the BICC signaling of the IPBCP message to the application server (AS), where the IPBCP message carries the DTMF capability negotiation information of the MGW;

The AS receives the BICC signaling of the load IPBCP message, and sends a SIP protocol message to the USS, where the DTMF capability negotiation information of the MGW is carried.

The steps of transmitting the DTMF signal out of band through the media channel include:

The MGW encodes the received DTMF signal according to the capability negotiation result and sends the DTMF signal to the USS through the established media channel;

The USS receives the encoded DTMF signal, and decodes the encoded DTMF signal according to the capability negotiation result.

After the USS and the MGW establish a media channel, before the MGW encodes the received DTMF signal, the method further includes: the AS sending a SIP message to the USS, indicating that the USS plays a sound; The media channel sends a media stream to the MGW.

The BICC network is a 3GPP R4 network.

In order to solve the above technical problem, the present invention also provides a transmission system for an out-of-band multi-tone dual-frequency signal, which is implemented based on a BICC network, including MSC, MGW, and USS:

The MSC is configured to: control the MGW, and send the message to the USS through the control channel.

MGW's DTMF capability negotiation information;

The MGW is configured to: receive a DTMF capability negotiation result sent by the USS, and establish a media channel and an outband transmission DTMF signal according to the DTMF capability negotiation result;

The USS is configured to: process the DTMF capability negotiation information and return a DTMF capability negotiation result, and establish a media channel and an outband transmission DTMF signal according to the DTMF capability negotiation result.

The MGW includes a capability negotiation module, a media channel establishment module, and a DTMF signal coding mode. a block and a signal transceiving module, wherein: the capability negotiation module is configured to: receive a capability negotiation result returned by the USS;

The media channel establishing module is configured to: establish a media channel with the USS when the capability negotiation is successful;

The DTMF signal encoding module is configured to: encode the DTMF signal according to the DTMF capability negotiation result of the capability negotiation module;

The signal transceiving module is configured to: send the encoded DTMF signal to the USS through the established media channel.

The USS includes a capability negotiation module, a media channel establishment module, a DTMF signal decoding module, and a signal transceiver module, where:

The capability negotiation module is configured to: receive DTMF capability negotiation information by using the control channel, process the DTMF capability negotiation information to generate a DTMF capability negotiation result; and return the DTMF capability negotiation to the MGW through the control channel. Result

The media channel establishing module is configured to: when the capability negotiation succeeds, establish a media channel with the MGW;

The DTMF signal decoding module is configured to: decode the DTMF signal according to the DTMF capability negotiation result of the capability negotiation module;

The signal transceiving module is configured to: receive the DTMF signal sent by the MGW through the established media channel, and send the decoded DTMF signal to the application server (AS).

The system further includes an AS, the MSC is configured to send DTMF capability negotiation information of the MGW to the USS through a control channel by: sending the DTMF capability negotiation information by using BICC signaling loaded with an IPBCP message. Give the AS;

The AS is configured to: send the DTMF capability negotiation information to the USS by using a SIP message;

The USS is configured to return a DTMF capability negotiation result in the following manner: sending the DTMF capability negotiation result to the AS by using a SIP message;

The AS is further configured to: send the DTMF capability negotiation result to the MGW by using BICC signaling loaded with an IPBCP message. The MGW further includes a DTMF signal detecting module configured to: detect whether a DTMF signal is received, and notify the DTMF signal encoding module to perform encoding when detecting.

In the transmission method and system for the out-of-band dual-tone multi-frequency signal of the present invention, the mobile switching center (MSC) transmits the capability negotiation information of the DTMF signal of the media gateway (MGW) to the USS through the control channel, and the USS processes the capability negotiation information and returns The result of the capability negotiation, if the negotiation is successful, the media channel is established; the outband transmission of the DTMF signal is realized through the established media channel, so as to support the transmission and reception of the multi-bit variable length button information, and fully utilize the functions of the existing USS, simplifying the application itself for the DTMF Signal parsing work.

BRIEF abstract

1 is a schematic structural diagram of a network element and a protocol according to the present invention;

2 is a schematic diagram of a transmission method of an out-of-band dual-tone multi-frequency signal according to the present invention;

3 is a signaling flow chart of an application example of the present invention.

Preferred embodiment of the invention

The main idea of the transmission method and system for the out-of-band dual-tone multi-frequency signal of the present invention is that before the transmission of the dual-tone multi-frequency (DTMF) signal in the BICC broadband network, the mobile switching center (MSC) transmits the media gateway to the USS through the control channel (MGW). The capability negotiation information of the DTMF signal, the USS processes the capability negotiation information and returns the capability negotiation result, and if the negotiation succeeds, the media channel is established; the outband transmission of the DTMF signal is implemented through the established media channel to support the multi-bit variable length button The information is sent and received, and the functions of the existing USS are fully utilized to simplify the application of the DTMF signal analysis by the application (the actual business process, such as the actual application such as IVR). Among them, the BICC network is a 3GPP R4 network.

As shown in FIG. 2, the dual tone multi-frequency signal transmission method of the present invention includes the following steps:

Step 201: The mobile switching center (MSC) sends the dual tone multi-frequency (DTMF) capability negotiation information of the media gateway (MGW) to the USS through the control channel;

The DTMF capability negotiation information includes negotiation parameters required for encoding.

In the actual network architecture, the MSC controls the MGW, and the MSC passes the Mc interface (media). The control interface) acquires the capabilities of the MGW, so the capability negotiation process is initiated by the MSC. Step 202: The USS processes the DTMF capability negotiation information, and returns a DTMF capability negotiation result to the MGW through the control channel.

Step 203: When the capability negotiation succeeds, the USS and the MGW establish a media channel according to the DTMF capability negotiation result, and transmit the DTMF signal out-of-band through the media channel.

If capability negotiation fails, the channel for out-of-band DTMF signal transmission will not be established, nor can DTMF transmission be implemented out-of-band.

In the BICC network, after the user presses a button on the mobile phone or other terminal, the button information arrives at the MSC, and the MSC transmits the signal to the MGW through the H.248 media control signaling.

The MGW encodes the received DTMF signal according to the media capability negotiation result, and sends the DTMF signal to the USS through the established media channel; the USS receives the encoded DTMF signal, and decodes the encoded DTMF signal according to the capability negotiation result, and The decoded DTMF signal is reported to the application server (AS).

The network structure, protocol, and signaling processing flow of the present invention will be described below with reference to the accompanying drawings.

As shown in FIG. 1 , the network elements and protocols involved in the present invention include:

The MSC (Mobile Switching Center) module adds an offer for DTMF codec negotiation in the IPBCP message;

The AS (Application Server) sends the offer negotiated by the DTMF codec in the IPBCP to the USS module through the SIP message.

The USS module processes the DTMF codec capability negotiation offer in the SIP message to generate a DTMF codec capability negotiation answer; establishes a media channel according to the IPBCP negotiated media information and the MGW Nb UP negotiation; sends the media stream to the MGW; accepts the MGW Using the negotiated DTMF encoding method to encode the DTMF information and decoding the upper 艮AS;

The MGW (Media Gate Way) module performs Nb UP negotiation with the USS; accepts the media stream sent by the USS; encodes the received DTMF and sends it to the USS. The present invention relates to protocols such as BICC, IPBCP, SIP, SDP, etc., as shown in the accompanying drawings. In order to implement the above method, the present invention provides a transmission system for an out-of-band multi-tone dual-frequency signal, which is implemented based on a BICC (3GPP R4) network, including a mobile switching center (MSC) and a media gateway (MGW) connected through a network. And media server (USS), where

The MSC is configured to control the MGW, and send DTMF capability negotiation information of the MGW to the USS by using a control channel;

The MGW is configured to receive a DTMF capability negotiation result sent by the USS, and establish a media channel and an outband transmission DTMF signal according to the DTMF capability negotiation result;

The USS is configured to process the DTMF capability negotiation information and return a DTMF capability negotiation result, and establish a media channel and an outband transmission DTMF message according to the DTMF capability negotiation result.

Specifically, the MGW includes a capability negotiation module, a media channel establishment module, a DTMF signal coding module, and a signal transceiving module, where: the capability negotiation module is configured to receive a capability negotiation result returned by the USS;

The media channel establishing module is configured to establish a media channel with the USS when the capability negotiation succeeds;

The DTMF signal encoding module is configured to encode the DTMF signal according to the DTMF capability negotiation result of the capability negotiation module;

The signal transceiving module is configured to send the encoded DTMF signal to the USS through the established media channel.

The capability negotiation module is configured to receive DTMF capability negotiation information by using the control channel, process the DTMF capability negotiation information to generate a DTMF capability negotiation result, and return the DTMF capability negotiation to the MGW by using the control channel. Result

The media channel establishing module is configured to establish a media channel with the MGW when the capability negotiation succeeds;

The DTMF signal decoding module is configured to decode the DTMF signal according to the DTMF capability negotiation result of the capability negotiation module; The signal transceiving module is configured to receive the DTMF signal sent by the MGW through the established media channel, and send the decoded DTMF signal to the application server (AS).

The system further includes an AS, where the MSC sends the DTMF capability negotiation information to the AS by using BICC signaling loaded with an IPBCP message, and the AS sends the DTMF capability negotiation information to the office by using a SIP message. The USS, and the DTMF capability negotiation result is sent to the MGW using the BICC signaling loaded with the IPBCP message; the USS sends the DTMF capability negotiation result to the AS by using a SIP message.

The MGW further includes a DTMF signal detecting module, configured to detect whether a DTMF signal is received, and notify the DTMF signal encoding module to perform encoding when detecting.

Applications

The following takes the RFC2833 capability negotiation as an example to introduce the out-of-band DTMF transmission process. As shown in FIG. 3, the signaling flow of the transmission of the outband DTMF for the automatic voice station (such as 10086) is as follows: Step 301: The MSC sends an IAM (Initial Address Message) message to the AS server, and the IAM message. The RFC2833 capability negotiation information (offer) carrying the MGW;

IAM is BICC signaling, in which IPBCP messages are loaded.

The capability negotiation information referred to in the present invention includes various parameters required for encoding.

The RFC2833 capability negotiation offer is expressed as follows: (m line increases the last 97, adds a new line a):

m=audio 5000 RTP/AVP 8 4 0 18 97

a=rtpma :97 telephone-event/8000/ 1

Among them, audio 5000 RTP means to use rtp transmission, 5000 ports, which is described in detail in SDP protocol; AVP 8 4 0 18 97 respectively indicate several encoding formats, and SDP protocol describes rtpmap:97 telephone-event/8000/ l is used to indicate that the MGW has DTMF encoding capability, and can of course be represented by other strings.

The complete request is as follows:

V=0 o=- 0 34309239 IN IP4 10.51.2.9

s=- c=IN IP4 10.51.2.9

t=0 0

a=ipbcp:l Request

m= audio 5000 RTP/AVP 8 4 0 18 97

a=ptime:20

a=rtpmap:96 VND.3GPP.IUFP/16000

a=rtpma :97 telephone-event/8000/ 1

Step 302: After receiving the IAM message, the AS server sends the RFC2833 capability negotiation information (the offer) to the USS through the INVITE message (SIP protocol);

Step 303: The USS processes the RFC2833 capability negotiation information (offer) in the INVITE message to generate an RFC2833 capability negotiation result (answer);

Step 304: The AS server returns the response of the USS to the MSC/MGW through the APM signaling (BICC signaling) that carries the IPBCP message.

The RFC2833 capability negotiation result (answer) message is as follows (m line adds the last 101, adds two a lines):

The m line in Offer represents the protocol type, port, and audio encoding type supported by the MGW.

The m line in ANSWSER indicates that the USS has selected the encoding types and protocols it supports from the offer.

m=audio 33942 RTP/AVP 18 101

a=rtpmap: 101 telephone-event/8000

a=fintp:101 0-15,32,36

The above two lines indicate that the USS also supports DTMF encoding and requires the MGW to press the buttons 0-15, 32,

36 is coded. The complete response message is as follows:

V=0

o=- 37000247 37000247 IN IP4 mpc9

s=media server session

t=0 0

a=ipbcp:l Accepted

m= audio 33942 RTP/AVP 18 101

c=IN IP4 10.200.250.74

a=rtpmap:96 VND.3GPP.IUFP/16000

a=sendrecv

a=rtpmap: 101 telephone-event/8000

a=fintp:101 0-15,32,36

Step 305: The USS and the MGW perform Nb UP negotiation according to the IPBCP capability negotiation result and establish a media channel.

Step 306: The AS server sends an info message (SIP protocol) to indicate that the USS plays the voice; Step 307: The MGW transmits the detected DTMF signal to the USS through the Nb interface according to the RFC2833 capability negotiation result according to the RFC2833 capability negotiation result;

Step 308: The USS parses the DTMF signal encoded by the RFC2833, and reports the parsed DTMF signal to the AS through an info message (SIP protocol); the AS server performs corresponding operations according to the button information.

The process ends.

One of ordinary skill in the art will appreciate that all or a portion of the above steps may be performed by a program to instruct the associated hardware, such as a read only memory, a magnetic disk, or an optical disk. Optionally, all or part of the steps of the above embodiments may also be used. One or more integrated circuits are implemented. Correspondingly, each module/unit in the foregoing embodiment may be implemented in the form of hardware, or may be implemented 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 In the transmission method and system for the out-of-band dual-tone multi-frequency signal of the present invention, the mobile switching center (MSC) transmits the capability negotiation information of the DTMF signal of the media gateway (MGW) to the USS through the control channel, and the USS performs the capability negotiation information. Process and return the capability negotiation result. If the negotiation is successful, the media channel is established. The outband transmission of the DTMF signal is realized through the established media channel to support the transmission and reception of the multi-bit variable length button information, and the functions of the existing USS are fully utilized to simplify the application. It works itself for the resolution of DTMF signals.

Claims

Claim

A method for implementing out-of-band multi-tone dual-frequency signal transmission in a media plane, the method comprising: in a bearer-independent call control protocol (BICC) network, a mobile switching center (MSC) passes a media gateway (MGW) through a control channel The dual tone multi-frequency (DTMF) capability negotiation information is sent to the media server (USS);

The USS processes the DTMF capability negotiation information, and sends the DTMF capability negotiation result to the MGW through a control channel;

When the capability negotiation is successful, the USS establishes a media channel with the MGW according to the DTMF capability negotiation result, and transmits the DTMF signal out-of-band through the media channel.

The method of claim 1, wherein the step of the MSC transmitting the DTMF capability negotiation information of the MGW to the USS by using the control channel includes:

The MSC sends the BICC signaling of the load IP bearer control protocol (IPBCP) message to the application server (AS), where the IPBCP message carries the DTMF capability negotiation information of the MGW; the AS receives the BICC signaling of the load IPBCP message. And sending a Session Initiation Protocol (SIP) message to the USS, where the DTMF capability negotiation information of the MGW is carried.

3. The method of claim 1, wherein the step of transmitting the DTMF signal out of band through the media channel comprises:

Receiving, by the USS, the encoded DTMF signal, according to the capability negotiation result, the encoded

The DTMF signal is decoded.

4. The method according to claim 3, wherein, after the USS and the MGW establish a media channel, before the MGW encodes the received DTMF signal, the method further includes: the AS sending a SIP to the USS a message indicating that the USS plays a voice; the USS sends a media stream to the MGW through the media channel.

The method of any of claims 1-4, wherein the BICC network is 3GPP R4 network.

6. A transmission system for out-of-band multi-tone dual-frequency signals, characterized in that the system is implemented based on a bearer-independent call control protocol (BICC) network, the system comprising a mobile switching center (MSC), a transmitting media gateway (MGW) ) and media server (USS);

The MSC is configured to: control the MGW, and go to the

The USS sends the DTMF capability negotiation information of the MGW.

The system of claim 6, wherein the MGW comprises a capability negotiation module, a media channel establishment module, a DTMF signal coding module, and a signal transceiver module;

The capability negotiation module is configured to: receive a capability negotiation result returned by the USS; and the media channel establishing module is configured to: when the capability negotiation is successful, establish a media channel with the USS;

The system of claim 7, wherein the USS includes a capability negotiation module, a media channel establishment module, a DTMF signal decoding module, and a signal transceiver module;

The media channel establishing module is configured to: establish a media channel with the MGW when the capability negotiation succeeds; The DTMF signal decoding module is configured to: decode the DTMF signal according to the DTMF capability negotiation result of the capability negotiation module;

9. The system of claim 6, wherein the system further comprises an AS,

The MSC is configured to send DTMF capability negotiation information of the MGW to the USS through a control channel by: transmitting the DTMF capability negotiation information to the BICC signaling by using a Load IP Bearer Control Protocol (IPBCP) message. AS;

The AS is configured to: send the DTMF capability negotiation information to the USS by using a Session Initiation Protocol (SIP) message;

The AS is further configured to: send the DTMF capability negotiation result to the MGW by using BICC signaling of the load IPBCP message.

10. The system of claim 7, wherein the MGW further comprises a DTMF signal detection module configured to: detect whether a DTMF signal is received, and notify the DTMF signal encoding module to encode when detected.

The system according to any one of claims 6 to 10, wherein the BICC network is a 3GPP R4 network.