CN1941819B - Method and system for transmitting speech service in Ethernet - Google Patents

Abstract

The present invention provides a system for transmitting voice services over Ethernet, and also provides a method for transmitting TDM voice services over Ethernet. When the client transmits TDM voice data to the central office, it is directly encapsulated in the Ethernet frame without Compressed data is sent to the central office equipment. After the central office equipment receives it, it restores the original voice data and line signals from the Ethernet frame and transmits it to the PSTN network. By using the invention, it is possible to realize more direct and concise voice transmission in the Ethernet-based broadband access network.

Description

A method and system for voice service transmission over Ethernet

technical field

The present invention relates to the technical field of communication, in particular to a method and system for transmitting voice services in Ethernet. the

Background technique

Voice services are mainly implemented in the Public Switched Telephone Network (PSTN). With the rapid development of broadband communications, it is already a trend to use Ethernet-based broadband packet networks as access networks to implement voice services. the

At present, VoIP (Voice over IP) is the main method for implementing voice services in broadband packet networks. Its basic principle is: the sender compresses and encodes the voice signals to be sent through a certain voice compression algorithm, and then converts these The compressed and encoded voice data is packaged into IP data packets according to IP and other related protocols, and then the IP data packets are transmitted to the receiver through the IP network. After the receiver extracts the compressed and encoded voice data from the received IP data packets, after decoding After decompression processing, the restored original voice signal is provided to the receiver user. It can be seen that this method transmits voice through the IP network. the

For the VoIP method, since the voice signal is processed using the IP layer protocol, it is required to be transmitted on an IP-based network, and the voice signal is compressed in order to occupy a smaller bandwidth. However, because of this, the equipment for implementing VoIP is relatively complex and costly; and because VoIP needs to compress the voice signal, the voice transmission delay is relatively large, and it is difficult to meet the delay requirements of the access network; in addition, When intercommunicating with the PSTN network, a dedicated conversion device is required to convert the protocol between VoIP and PSTN signaling, which makes the implementation cost relatively high. the

Another way to transmit the voice in the broadband packet network is to encapsulate the E1/T1 used by the PSTN network into data packets for transmission, and the E1/T1 carries the voice service. However, since the rate of E1/T1 is fixed, no matter whether the carried voice data is valid or not, it will occupy a fixed bandwidth. A complete E1 needs to be occupied, resulting in low bandwidth utilization of the access network. In addition, a special circuit is required to realize the centralized convergence of voice channels, resulting in high cost.

Contents of the invention

In view of this, the main purpose of the present invention is to provide a method and system for transmitting TDM voice services over Ethernet, so as to realize voice transmission more directly and concisely in an Ethernet-based broadband access network. the

The voice service provided by the present invention is transmitted in an Ethernet system, including a central office device and a client device, and the central office device includes a central office voice access module (101) and a central office Ethernet module (102), and the client End equipment comprises client voice access module (104) and client ethernet module (103), according to call protocol dynamic configuration PSTN interface call channel and the corresponding relationship of telephone interface at central office equipment,

During downlink transmission, the central office voice access module (101) is used to receive the PSTN data code stream from the PSTN interface, parse out the voice data and encapsulate it as an Ethernet frame and send it to the central office Ethernet module (102), the Ethernet frame The source address and the destination address are respectively the MAC of the central office equipment and the MAC of the client equipment, and also include the corresponding telephone interface identification of the voice path of the PSTN interface; the central office Ethernet module (102) is used to encapsulate the Ethernet The frame is sent to the client Ethernet module (103); the client voice access module (104) is used to decapsulate after obtaining the Ethernet frame from the client Ethernet module (103), obtain voice data, and according to the The telephone interface identifier sends the voice data to the corresponding telephone interface,

When uplink transmission, client voice access module (104) is used for receiving voice service flow from telephone interface, extracts voice data and encapsulates into Ethernet frame and sends to client Ethernet module (103), in this Ethernet frame The source address and the destination address are respectively the MAC of the client equipment and the MAC of the central office equipment, and also include the telephone interface identification of the telephone interface receiving the voice service flow; the client Ethernet module (103) is used for encapsulating the Ethernet The network frame is sent to the local end Ethernet module (102); the local end voice access module (101) is used to receive the Ethernet frame from the central office Ethernet module (102), resolves the voice data, and according to the telephone interface in the frame Identifies sending voice data to the corresponding PSTN interface

Wherein, the central office voice access module 101 includes:

PSTN deframing module 202, used for parsing PSTN data code stream, extracting voice data and storing in sending buffer, extracting control protocol data and sending to protocol processing module 215;

The central office Ethernet framing module 204 is used to take out the corresponding voice data stored in the sending buffer according to the corresponding relationship between the PSTN interface voice channel and the telephone interface dynamically configured by the protocol processing module 215 to form an Ethernet network containing the telephone interface identifier. frame, sent to the central office Ethernet module 102;

The central office Ethernet deframing module 214 is used to analyze the received Ethernet frame according to the corresponding relationship between the PSTN interface voice channel and the telephone interface dynamically configured by the protocol processing module 215, and extract the voice data and store it in the receiving cache;

PSTN framing module 212, is used for reading voice data and encapsulating as PSTN data stream from receiving cache;

The protocol processing module 215 is configured to analyze the PSTN protocol to configure the corresponding relationship between the PSTN interface voice channel and the telephone interface. the

Wherein, the central office voice access module 101 further includes: HDB3/NRZ conversion module 201, which is used to convert the HDB3 code data input from the PSTN interface into NRZ code data and send it to the PSTN deframing module 202; NRZ/HDB3 conversion module 211 , configured to convert the NRZ code data sent by the PSTN deframing module 202 into HDB3 code data and output it to the PSTN interface. the

Wherein, the protocol processing module 215 includes:

The processor 2152 is used to implement the parsing of the PSTN protocol to configure the corresponding relationship between the voice channel of the PSTN interface and the telephone interface;

The configuration management interface 2153 is used to provide the corresponding relationship between the voice channel of the configured PSTN interface and the telephone interface to the central office Ethernet framing module 204 and the central office Ethernet deframing module 214 according to the instruction of the processor 2152;

The HDLC interface 2151 is used for forwarding protocol data between the PSTN deframing module 202 , the PSTN framing module 212 and the processor 2152 . the

Wherein, the client voice access module 104 includes:

The client Ethernet deframing module 301 is used to parse the received Ethernet frame, and take out the voice data and store it in the receiving cache;

Clock recovery module 304, for recovering the clock of voice data;

Voice data output module 303, for taking out voice data from receiving cache according to the clock of clock recovery module 304, output to telephone interface;

The voice data input module 313 is used for storing the voice data received from the telephone interface into the sending buffer. the

The client Ethernet framing module 311 is configured to take out voice data stored in the sending buffer to form an Ethernet frame and send it to the client Ethernet module 103 . the

The TDM voice service provided by the present invention transmits the method in Ethernet, and in the call process, the central office equipment establishes the corresponding relationship between the voice path of the PSTN interface and the telephone interface according to the call, and the method includes downlink transmission and uplink transmission; the downlink transmission includes the following steps:

A. The central office equipment receives the PSTN data code stream from the PSTN interface, parses the voice data and encapsulates it into an Ethernet frame; the source address and destination address of the Ethernet frame are the MAC of the central office equipment and the MAC of the client equipment, respectively. Including the telephone interface identifier corresponding to the voice path of the PSTN interface;

B. The encapsulated Ethernet frame is sent from the central office device to the client device;

C. The client device decapsulates the Ethernet frame after obtaining the Ethernet frame, obtains the voice data, and sends the voice data to the corresponding telephone interface according to the telephone interface identifier in the frame;

Uplink transmission includes the following steps:

A', the client device receives voice data from the telephone interface, and encapsulates the voice data into an Ethernet frame; wherein the frame source address and destination address are respectively the MAC of the client device and the MAC of the central office device, and also include the telephone interface logo;

B', the encapsulated Ethernet frame is sent by the client device to the central office device;

C', the central office device decapsulates the Ethernet frame after obtaining the Ethernet frame, obtains the voice data, and sends the voice data to the corresponding PSTN interface according to the telephone interface identifier in the frame. the

Wherein, the step A includes sub-steps:

The central office device receives the PSTN data code stream from the PSTN interface, parses out the voice data and stores it in the buffer corresponding to the PSTN interface;

According to the corresponding relationship between the telephone channel and the telephone interface configured on the PSTN interface, the buffered voice data is read from the buffer and encapsulated into an Ethernet frame. the

Wherein, the step C includes sub-steps:

The client device deframes the received Ethernet frame, takes out the encapsulated voice data and stores it in the receiving buffer corresponding to the destination telephone interface identifier in the frame;

Recover the clock consistent with the downlink voice data;

Use the recovered clock to take out the voice data from the receiving buffer and send it to the corresponding telephone interface. the

Wherein, described step A ' comprises sub-steps:

The client device receives voice data from the telephone interface and stores it in the buffer corresponding to the telephone interface;

The voice data is taken out from the cache and encapsulated into an Ethernet frame. the

Wherein, described step C ' comprises substep:

The central office device decapsulates the received Ethernet frame, obtains the voice data and the telephone interface identifier, and stores the voice data into the voice channel corresponding to the PSTN interface according to the configured corresponding relationship between the voice channel of the PSTN interface and the telephone interface. in cache;

Read the voice data from the cache, encapsulate it as a PSTN data stream and send it to the corresponding PSTN interface. the

Wherein, the voice data is TDM voice service data. the

As can be seen from the above method, compared with the VoIP technology described in the background technology, the present invention directly encapsulates the voice data in the Ethernet frame for transmission, does not need complex voice data compression and VoIP protocol processing, and reduces the voice traffic. The time delay and the complexity of accessing PSTN greatly reduce the difficulty and cost of equipment implementation. the

Compared with E1/T1 encapsulated in Ethernet for transmission, the voice data of the present invention is dynamically encapsulated in the Ethernet frame, and the unused channel does not generate a data frame, so only the effective voice data in the conversation is processed, reducing the Useless data occupies bandwidth. Moreover, the number of voice channels at a site is arbitrary, unlike E1, where the minimum unit must be 30 voice channels occupying 2M bandwidth, so the present invention is very easy to realize the convergence of voice channels at the PSTN interface. the

Description of drawings

Fig. 1 is a system structure diagram of TDM voice service transmission in Ethernet according to the present invention. the

Figure 2 is a block diagram of voice access at the central office. the

Fig. 3 is a diagram of the client voice access module. the

Fig. 4 is a flow chart of downlink processing of TDM voice service transmission in Ethernet. the

Fig. 5 is a flow chart of uplink processing of TDM voice service transmission in Ethernet. the

Detailed ways

The present invention considers that the Ethernet-based broadband packet network generally adopts Ethernet devices such as optical fiber transceivers and EPONs. Because it is optical fiber transmission, the bandwidth is very large, and each voice path only needs a bandwidth of 64K. Therefore, the present invention directly uses TDM voice data and user line signals are encapsulated in Ethernet frames, and transmitted to the central office equipment without compression processing. After receiving them, the central office equipment recovers the original voice data and line signals from the Ethernet frames. transmitted to the PSTN network. Moreover, since the voice data is processed at the Ethernet layer instead of the high-layer protocol, the complexity of the processing is reduced. the

The TDM voice service access is jointly completed by the service access interface of the client equipment (such as the telephone interface) and the service interface of the central office equipment (such as the PSTN interface). The two interfaces can establish a corresponding relationship through configuration. The corresponding relationship corresponds to the access of different TDM voice channels, so that the central office can configure the connection conveniently. Referring to the accompanying drawings, the present invention will be described in detail below. the

FIG. 1 shows the system for realizing the transmission of TDM voice services on Ethernet according to the present invention. The central office equipment of the system includes a central office voice access module 101 and an central office Ethernet module 102 . The central office voice access module 101 is responsible for the framing, deframing, convergence of voice channels, and the realization of PSTN interfaces (such as: No. 1/7 signaling/V5/PRI interfaces, etc.) of Ethernet frames; the central office Ethernet module 102 is responsible for converging multiple client devices and separating voice services from other services. the

The client device of the system includes a client voice access module 104 and a client Ethernet module 103 . The client voice access module 104 is responsible for the framing and deframing of voice and line signaling data to the Ethernet frame, and the realization of the telephone interface; the client Ethernet module 103 is responsible for transferring the Ethernet frame of the voice data and other business The Ethernet frames are concentrated to the central office equipment. the

The central office equipment and each client equipment need to be pre-assigned a unique MAC address for identification, and the PSTN interface of the central office equipment uses sequence numbers to identify voice channels, and the client equipment also uses sequence numbers to identify telephone interfaces. When the system transmits TDM voice services, a corresponding relationship between the voice channel of the PSTN interface and the telephone interface will be dynamically established in the central office equipment. The basic process of the downlink and uplink transmission is as follows:

The downlink transmission of the TDM voice service includes the following steps: After receiving the PSTN code stream (such as the HDB3 code stream) from a certain PSTN interface, the central office voice access module 101 extracts the voice data and encapsulates it into an Ethernet frame, and the source address in the frame , the destination address are respectively the MAC of the central office equipment and the MAC of the client equipment, and also include the corresponding telephone interface number of the PSTN interface that receives the PSTN code stream; 102 sends to the client Ethernet module 103; The client voice access module 104 decapsulates after obtaining the Ethernet frame from the client Ethernet module 103, obtains voice data, and then sends the voice data to Corresponding telephone interface. the

For the uplink transmission of the TDM voice service, it is the inverse process of the downlink transmission, including the following steps: After receiving the voice service flow from a certain telephone interface, the client voice access module 104 extracts the voice data and encapsulates it into an Ethernet frame. The source address and the destination address are respectively the MAC of the client equipment and the MAC of the central office equipment, and also include the telephone interface number of the telephone interface receiving the voice service flow; the encapsulated Ethernet frame is sent by the client Ethernet module 103 To the central office Ethernet module 102; The central office voice access module 101 decapsulates after obtaining the Ethernet frame from the central office Ethernet module 102, obtains voice data, and then sends the voice data to the corresponding Voice channel of the PSNT interface. the

The structure of the voice access module in the central office equipment of the present invention is described in detail below. The general PSTN interface is an HDB3 code stream. As shown in Figure 2, the central office voice access module 101 includes the following submodules:

The HDB3/NRZ conversion module 201 is used to convert the HDB3 code input of the PSTN interface into NRZ code. the

PSTN deframing module 202, for parsing the NRZ data stream, extracting the voice data and storing it in the transmission cache 203 in sequence, in this embodiment, there is a corresponding relationship between the PSTN interface and the cache address, and the data processed for the voice channel of different PSTN interfaces Store them in different addresses of the sending buffer 203; on the other hand, extract the control protocol data and send them to the protocol processing module 215 for protocol processing. the

Ethernet framing module 204, according to the corresponding relationship between the voice path of the PSTN interface of dynamic configuration and the telephone interface, the voice data stored in the sending cache 203 position corresponding to the PSTN interface is taken out, and the frame header information is added to form an Ethernet frame, and the Ethernet frame is sent. Send it to the central office Ethernet module 102. The source address and destination address in the frame header information are the MAC of the central office device and the MAC of the client device respectively, and also include the telephone interface number corresponding to the voice path of the PSTN interface. the

Ethernet deframing module 214 determines the voice data of which client the frame belongs to according to the source MAC address and the telephone interface number in the received Ethernet frame header, and according to the corresponding relationship between the voice path and the telephone interface of the PSTN interface of dynamic configuration, the The voice data in the frame is taken out and stored in the corresponding address of the receive buffer 213 corresponding to the voice channel of the PSTN interface. the

The PSTN framing module 212 sequentially reads out the buffered voice data from the receiving buffer 213, adds the frame header and the carried protocol data to form the NRZ code stream of the PSTN interface transmission data. the

The NRZ/HDB3 conversion module 211 is responsible for converting the data sent by the PSTN interface from NRZ codes to HDB3 codes and sending them to the PSTN interface. the

The protocol processing module 215 includes an HDLC interface 2151 , a processor 2152 , and a configuration management interface 2153 . The HDLC interface 2151 is responsible for forwarding protocol data between the PSTN interface and the processor 2152 . Processor 2152 is responsible for processing the call protocol received by the PSTN interface (including protocol processing such as Signaling No. 1/7/V5/PRI), including dynamically configuring the corresponding relationship between the voice channel of the PSTN interface and the telephone interface according to the call protocol (that is, establishing voice channel), and also includes the processing of user signaling on the telephone interface (including ring control, on-hook detection, etc.). Configure the management interface 2153 to realize the control and management of the hardware circuit by the processor 2152, including configuring the MAC addresses of the central office and the client, the number of telephone users of the client, and receiving instructions from the processor 2152 to dynamically configure PSTN calls and client calls. correspondence etc. the

In the access network, according to the law of statistical multiplexing, the number of uplink calls and the total number of users can be configured according to a certain ratio to meet the actual use requirements, and the system needs to realize the convergence of the calls. In this system, the protocol processing module 215 dynamically configures the corresponding relationship between the voice channel of the PSTN interface and the telephone interface according to the received PSTN protocol, and the Ethernet framing and deframing module according to the corresponding relationship between the voice channel and the telephone interface of the dynamically configured PSTN interface, It only processes the voice data of the telephone interface that has been assigned a voice channel, and does not send and receive the data frame of the telephone interface that has not been allocated a voice channel, so as to realize the convergence and convergence of voice channels ingeniously. the

The structure of the voice access module in the client device of the present invention is described in detail below, as shown in Figure 3, including the following modules:

The client Ethernet deframing module 301 takes out the voice data from the received Ethernet frame and stores it in the receiving buffer 302 . the

The clock recovery module 304 recovers the clock of voice data, which is used for input and output of voice interface data. Among them, the clock of the voice data can be recovered according to the flow of incoming data in the receiving buffer 302. This can be based on the principle of a digital phase-locked loop, and the state output of the receiving buffer 302 can be converted into the phase detection output of the downlink clock and the local recovered clock, and the local clock can be obtained. The local recovered clock with the same frequency as the terminal clock, and ensure that the output jitter characteristics of the recovered clock meet the requirements. Of course, other clock methods may also be used for synchronization, for example, carrying time synchronization information in Ethernet frames to achieve synchronization between the sender and the receiver. the

The voice data output module 303 takes out the voice data from the receiving buffer 302, and outputs it to the user through a telephone interface (such as a TDMbus interface). the

The voice data input module 313 receives the voice data from the telephone interface and stores it in the transmission buffer 312 . the

The client Ethernet framing module 311 takes out the voice data stored in the sending buffer 312 and adds frame header information to form an Ethernet frame. The source address and destination address in the frame header information are respectively the MAC of the client device and the MAC of the central office device, and the frame also includes the serial number of the telephone interface for receiving voice data. It should be noted that since only call data is stored in the sending buffer 312, only the data of the ongoing call is sent here, reducing bandwidth occupation by useless data. the

What needs to be explained here is that the above describes the system of the present invention by taking the downlink and uplink transmissions as examples respectively. In the specific implementation process, the module corresponding to the uplink and downlink may be realized by a module with bidirectional functions, such as HDB3/NRZ conversion Module, NRZ/HDB3 conversion module is realized by a NRZ/HDB3 bidirectional conversion module, and PSTN or Ethernet deframing module and framing module are respectively realized by a bidirectional interface decomposing/framing module, receiving and sending buffer It is implemented by a buffer, and the voice data input and output modules are implemented by a bidirectional input/output module and so on. the

Referring to Figs. 1-3 below, the method for transmitting TDM voice service in Ethernet of the present invention will be described in detail for the downlink and uplink respectively as examples. The flowchart of the downlink transmission shown in Figure 4 includes the following steps:

In advance, the central office equipment establishes a corresponding relationship between a PSTN interface voice channel and a telephone interface, that is, establishes a voice channel. The voice path can be established during the call process, and the protocol processing module 215 and the superior bureau perform PSTN protocol processing, and configure the connection relationship between the PSTN interface and the telephone interface according to the PSTN protocol to establish the voice path. The establishment of the voice channel is standard, and will not be described in detail in the present invention. The processing of the downlink transmission of the data of the present invention comprises the following steps:

Step 401: The HDB3/NRZ conversion module 201 receives the HDB3 code stream of the PSTN interface, converts it into an NRZ code stream, and sends it to the PSTN deframing module 202 . the

Step 402: The PSTN deframing module 202 parses the received NRZ data code stream, extracts the voice data and stores them in sequence in the address of the sending buffer 203 corresponding to the PSTN interface, and simultaneously extracts the control protocol data and sends it to the protocol processing module 215 for protocol processing. deal with. the

Step 403: Ethernet framing module 204 reads out the buffered voice data from the sending buffer 203 address corresponding to the PSTN interface according to the corresponding relationship between the channel of the PSTN interface configured by the processor 2152 of the protocol processing module 215 and the telephone interface , and add information such as the MAC address and the destination telephone interface to encapsulate into an Ethernet frame and send it to the Ethernet module 102 at the central office. Wherein, the source and destination MAC addresses are the MAC addresses of the central office equipment and the client equipment respectively, and the destination telephone interface is the telephone interface corresponding to the voice path of the configured PSTN interface. the

Step 404: The central office Ethernet module 102 sends the encapsulated Ethernet frame to the destination client device through the Ethernet network, and is received by the client Ethernet module 103 of the destination client device. the

Step 405 : the client Ethernet module 103 sends the received Ethernet frame to the client Ethernet deframing module 301 . the

Step 406: The client Ethernet deframing module 301 deframes the received Ethernet frame, takes out the encapsulated voice data and stores it in the receiving buffer 302 address corresponding to the destination telephone interface in the frame;

Step 407: The clock recovery module 304 uses a digital phase-locked loop to recover a clock consistent with the downlink voice data according to the traffic statistics of the voice data stored in the cache. the

Step 408: The voice data output module 303 takes out the voice data from the receiving buffer 302 address corresponding to the destination telephone interface according to the recovered clock, and sends it to the telephone interface circuit (eg, TDMbus interface) for output. the

See the flowchart of uplink transmission shown in Figure 5, including the following steps:

Step 501: The voice data input module 313 stores the voice data received from the telephone interface into the transmission buffer 312 . The clock recovered from the downlink data is used here, so that the uplink data rate is consistent with the downlink, and the central office does not need to recover the clock from the uplink data, and can directly use the downlink clock. the

Step 502 : The client Ethernet framing module 311 takes out the voice data stored in the transmission buffer 312 , adds frame header information such as MAC address to form an Ethernet frame, and sends it to the client Ethernet module 103 . Wherein, the source and destination MAC addresses are respectively the MAC addresses of the client device and the central office device, and also carry the serial number of the telephone interface. the

Step 503: The client Ethernet module 103 sends the encapsulated Ethernet frame to the destination central office device through the Ethernet network, and the central office Ethernet module 102 of the destination central office device receives it. the

Step 504 : the central office Ethernet module 102 sends the received Ethernet frame to the central office Ethernet deframing module 214 . the

Step 505: The central office Ethernet deframing module 214 determines the voice data of the client and which telephone interface the frame belongs to according to information such as the source MAC address in the received Ethernet frame header, and according to the dynamically configured PSTN interface voice path and telephone interface The corresponding relationship, the voice data in the frame is taken out and stored in the address corresponding to the channel of the PSTN interface in the receiving buffer 213 . the

Step 506: The PSTN framing module 212 sequentially reads the voice data from the receiving buffer 213, adds the frame header and the carried protocol data, forms the NRZ code stream of the PSTN interface transmission data, and sends it to the NRZ/HDB3 conversion module 211. the

Step 507: The NRZ/HDB3 conversion module 211 converts the data sent by the PSTN interface from NRZ code to HDB3 code, and sends it to the corresponding PSTN interface. the

As can be seen from the above embodiments, the present invention directly encapsulates the voice data in the Ethernet frame for transmission when realizing access to the PSTN network, without complex voice data compression and VoIP protocol processing, reducing the time delay and complexity of processing , greatly reducing the implementation difficulty and cost of the device; and, because the voice data is dynamically encapsulated in the Ethernet frame, the present invention does not generate a data frame for the unused channel, so only the effective voice data in the conversation is processed, reducing the Useless data occupies the bandwidth, and it is very easy to realize the convergence of the voice channel on the PSTN interface. the

The above description is based on the TDM voice service. When the PSTN adopts other methods to realize the voice service, such as the CDM voice service or the FDM voice service, it is also applicable to the present invention and will not be repeated here. the

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the scope of the present invention. within the scope of protection. the

Claims (11)

1. a voice service is in the Ethernet system for transmitting, comprise local side apparatus and client device, it is characterized in that, described local side apparatus comprises local side speech access module (101) and local side ethernet module (102), described client device comprises client speech access module (104) and client ethernet module (103), at local side apparatus according to the speech channel of hello protocol dynamic-configuration PSTN interface and the corresponding relation of telephony interface

When descending transmission, local side speech access module (101) is used for receiving the PSTN data code flow from the PSTN interface, parsing voice data is encapsulated as ethernet frame and sends to local side ethernet module (102), this ethernet frame source address, destination address are respectively the MAC of local side apparatus, the MAC of client device, also comprise the pairing telephony interface sign of speech channel of described PSTN interface; Local side ethernet module (102) is used for packaged ethernet frame is sent to client ethernet module (103); Client speech access module (104) is used for obtaining to carry out decapsulation behind the ethernet frame from client ethernet module (103), obtains voice data, and according to the sign of the telephony interface in the frame voice data is sent to corresponding telephony interface,

When uplink, client speech access module (104) is used for receiving voice service stream from telephony interface, extracting voice data is packaged into ethernet frame and sends to client ethernet module (103), source address, destination address are respectively the MAC of client device, the MAC of local side apparatus in this ethernet frame, also comprise the telephony interface sign of the telephony interface of described reception voice service stream; Client ethernet module (103) is used for packaged ethernet frame is sent to local side ethernet module (102); Local side speech access module (101) is used for receiving ethernet frame from local side ethernet module (102), parses voice data, and according to the sign of the telephony interface in the frame voice data is sent to corresponding PSTN interface.

2. system according to claim 1 is characterized in that, described local side speech access module (101) comprising:

PSTN separates frame module (202), is used to resolve the PSTN data code flow, extracts voice data and deposits in and send buffer memory, extract the control protocol data and send to protocol process module (215);

The local side Ethernet becomes frame module (204), be used for according to the speech channel of the PSTN interface of protocol process module (215) dynamic-configuration and the corresponding relation of telephony interface, take out the ethernet frame that formation contains described telephony interface sign sending the corresponding voice data of storing in the buffer memory, send to local side ethernet module (102);

The local side Ethernet is separated frame module (214), is used for resolving the ethernet frame that receives according to the speech channel of the PSTN interface of protocol process module (215) dynamic-configuration and the corresponding relation of telephony interface, extracts voice data and deposits the reception buffer memory in;

PSTN becomes frame module (212), is used for reading voice data from the reception buffer memory and is encapsulated as the PSTN data code flow;

Protocol process module (215) is used for the PSTN agreement is resolved to dispose the corresponding relation of PSTN interface speech channel and telephony interface.

3. system according to claim 1 is characterized in that, described local side speech access module (101) further comprises:

HDB3/NRZ modular converter (201) is used for being converted to from the HDB3 code data of PSTN interface input the NRZ code data and sends to PSTN and separate frame module (202);

NRZ/HDB3 modular converter (211) is used for being converted to the HDB3 code data and outputing to the PSTN interface separated NRZ code data that frame module (202) sends over by PSTN.

4. system according to claim 2 is characterized in that, described protocol process module (215) comprising:

Processor (2152) is used to realize to the parsing of PSTN agreement with the speech channel of disposing described PSTN interface and the corresponding relation of telephony interface;

Configuration management interface (2153), the corresponding relation that is used for the speech channel of the described PSTN interface that will dispose according to the indication of processor (2152) and telephony interface offers the local side Ethernet and becomes frame module (204) and local side Ethernet to separate frame module (214);

HDLC interface (2151) is used for the forwarding that PSTN separates protocol data between frame module (202), PSTN one-tenth frame module (212) and the processor (2152).

5. system according to claim 1 is characterized in that, described client speech access module (104) comprising:

Client ethernet is separated frame module (301), is used to resolve the ethernet frame of reception, takes out voice data and deposits in the reception buffer memory;

Clock recovery module (304) is used to recover the clock of voice data;

Voice data output module (303) is used for taking out voice data according to the clock of clock recovery module (304) from receiving buffer memory, outputs to telephony interface;

Voice data input module (313), the voice data that is used for receiving from telephony interface deposits the transmission buffer memory in.

Client ethernet becomes frame module (311), is used for that the voice data that the transmission buffer memory is stored is taken out the formation ethernet frame and sends to client ethernet module (103).

6. a TDM voice service is characterized in that in the method that Ethernet transmits local side apparatus is according to the speech channel of call setup PSTN interface and the corresponding relation of telephony interface in calling procedure, and this method comprises downlink transfer and uplink;

Downlink transfer may further comprise the steps:

A, local side apparatus receive the PSTN data code flow from the PSTN interface, parse voice data and are packaged into ethernet frame; Wherein this ethernet frame source address, destination address are respectively the MAC of local side apparatus, the MAC of client device, also comprise the pairing telephony interface sign of speech channel of described PSTN interface;

B, packaged ethernet frame send to client device by local side apparatus;

C, client device obtain to carry out decapsulation behind the described ethernet frame, obtain voice data, and according to the sign of the telephony interface in the frame voice data are sent to corresponding telephony interface;

Uplink may further comprise the steps:

A ', client device receive voice data from telephony interface, and voice data is packaged into ethernet frame; Wherein this frame source address, destination address are respectively the MAC of client device, the MAC of local side apparatus, also comprise the sign of described telephony interface;

B ', packaged ethernet frame send to local side apparatus by client device;

C ', local side apparatus obtain to carry out decapsulation behind the described ethernet frame, obtain voice data, and according to the sign of the telephony interface in the frame voice data are sent to corresponding PSTN interface.

7. method according to claim 6 is characterized in that, described steps A comprises substep:

Local side apparatus receives the PSTN data code flow from the PSTN interface, parses voice data and deposits PSTN interface corresponding cache in;

According to the speech channel of configuration PSTN interface and the corresponding relation of telephony interface, the voice data that reads out buffer memory from buffer memory is packaged into ethernet frame.

8. method according to claim 6 is characterized in that, described step C comprises substep:

Client device is separated frame with the ethernet frame that receives and is handled, and takes out packaged voice data and deposits in the reception buffer memory corresponding with purpose telephony interface sign in the frame;

Recover clock with the down voice data consistent;

From receive buffer memory, take out voice data with the clock that recovers, send to corresponding telephony interface.

9. method according to claim 6 is characterized in that, described steps A ' comprise substep:

Client device receives voice data from telephony interface, deposits the telephony interface corresponding cache in;

The access of postponing goes out described voice data and is packaged into ethernet frame.

10. method according to claim 6 is characterized in that, described step C ' comprises substep:

Local side apparatus carries out decapsulation with the ethernet frame that receives, and obtains voice data and telephony interface sign, according to the speech channel of the PSTN interface that disposes and the corresponding relation of telephony interface, described voice data is deposited in the speech channel corresponding cache of described PSTN interface;

From buffer memory, read voice data, be encapsulated as the PSTN data code flow and send to corresponding PSTN interface.

11. method according to claim 6 is characterized in that, described voice data is TDM voice service data.

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