CN102006503B - Wideband data communication system and method for integrating IP network and cable television network - Google Patents

Abstract

The invention relates to a broadband data communication system and method for merging an IP network and a cable TV network. A terminal and a converged channel gateway establish an end-to-end bidirectional channel in the IP network; Communication channel: the terminal sends the uplink IP packet to the fusion channel gateway through the IP network two-way communication channel, the fusion channel gateway obtains the uplink IP packet from the IP network, queries the address mapping table and performs address conversion, and sends the converted uplink IP packet to the IP network; the fusion channel gateway receives the corresponding downlink IP packet from the IP network, queries the address mapping table and performs address translation, and the fusion channel gateway passes the converted downlink IP packet through the two-way channel of the IP network, or through the IP/DVB gateway and The cable television network constitutes a one-way communication channel from the gateway to the terminal, or sends to the terminal through a two-way communication channel and a one-way communication channel at the same time.

Description

Broadband data communication system and method integrating IP network and cable television network

technical field

The invention relates to broadband data communication technology, in particular to a broadband data communication system and method for merging IP network and cable TV network.

Background technique

The cable TV network is a point-to-multipoint tree-type network structure broadcasting and television broadband integrated network. The network has a broadband downlink broadcast channel and divides signals according to frequency division multiple access. In order to realize two-way interactive services on the cable TV network, two-way data transmission must be solved. The methods for realizing two-way data transmission are usually divided into two categories: one uses technologies including Docsis, MoCA, HiNOC, HomePlug AV, HPHA, WLAN, etc. Carry out two-way transformation; another type uses out-of-band methods to solve uplink data transmission, such as ADSL, GPRS, CDMA, Wifi, Bluetooth and other technologies.

The structural diagram of the VOD service system in the environment where the IP network and the cable TV network coexist is shown in Figure 1, taking the VOD service system in the environment where the IP network and the cable TV network are integrated as an example. The system includes VOD service server, session and resource management server, IP/DVB gateway, digital set-top box. The general flow of the VOD business is as follows: the digital set-top box sends an on-demand request to the VOD service server through the IP network; the VOD service server sends a frequency point application instruction to the session and resource management server through the IP network; VOD service server sends frequency point information, IP address of IP/DVB gateway and data receiving port to VOD service server through IP network; VOD service server sends frequency point information to digital set-top box through IP network, and VOD service server sends audio The video data is sent to the IP/DVB gateway with the specified IP address and port; the IP/DVB gateway receives the audio and video data, converts the data into a moving image MPEG-TS transmission stream, and sends the data to the digital set-top box through the cable TV network; the digital The set-top box locks the frequency point, receives data on the frequency point, converts the data and decodes it for display. It can be seen that in an environment where a two-way IP network and a one-way cable TV broadcast network coexist, two-way interactive services usually use the cable TV network to download content data and use the IP network to transmit control signaling.

Related patents are as follows:

Chinese Patent No. 200610035447.8 discloses "a realization method of a two-way IP transmission system based on a cable TV network", which consists of a two-way IP data network, an IP/DVB gateway, a QAM modulator, a digital cable TV network, and a digital TV receiving terminal Box RS232/network protocol transponder. The digital TV receiving terminal sends uplink IP packets to the two-way IP data network through the RS232/network protocol transponder. The downlink IP packet is sent to the digital TV receiving terminal by the IP/DVB gateway and QAM modulator through the digital cable TV network.

Chinese Patent No. 200710001262.X discloses "system, method and equipment for providing bidirectional services in a separated bidirectional network". This patent is aimed at different bidirectional services in digital TV networks, and different signal conversion devices are used for signal conversion. At the same time, it also needs Integrate different clients in the set-top box to perform corresponding business processing. The patent can uniformly perform conversion processing for various bidirectional services in a separated bidirectional network. The method includes the following steps: the two-way network switching device receives at least one kind of two-way service content information, converts the received two-way service content information, and sends the converted two-way service content information. At the same time, the invention discloses that two-way service content information is provided in a separated two-way network, and the received different two-way service content information is converted and processed respectively; the two-way service receiving and processing equipment can receive and process various two-way service content information, and can target Different businesses are dealt with separately.

Other existing services are similar to VOD services. When using IP and cable TV networks, the service server needs to choose to use cable TV network or IP network to transmit data. When using cable TV network to transmit data, audio and video content needs to be encapsulated into MPEG- TS transmission stream, the two-way interactive service developed and provided in this way is difficult, poor in network adaptability, and poor in portability; in addition, the existing patent "200610035447.8" focuses on transmission, and the separation of its downlink data uses a specific IP network switch. In terms of network deployment, IP network switches and IP/DVB gateways need to be in the same subnet; the patent "200710001262.X" focuses on content conversion processing, and its bidirectional network conversion equipment is a specific routing device that must be deployed at the access of the set-top box network segment.

Contents of the invention

The purpose of the present invention is, in order to make the business server not need to specially encapsulate the audio and video content into MPEG-TS transmission stream, realize data communication in the environment of better fusion IP network and cable TV network, make full use of IP network and wired Bandwidth resources for TV networks.

In order to realize the purpose of the above invention, the present invention proposes a broadband data communication system that integrates an IP network and a cable TV network, and the system includes: an IP network, an IP/DVB gateway, a cable TV network and a terminal;

The IP/DVB gateway is responsible for receiving the MPEG-TS transport stream from the IP network, converting the MPEG-TS transport stream into a baseband signal, and modulating it to a frequency point, passing through the IP/DVB gateway The RF transmitter is sent to said cable television network;

Described terminal adopts the equipment that can not only receive DVB data broadcast from cable TV network but also can access IP network;

The terminal is connected to the IP/DVB gateway through a cable TV network;

It is characterized in that,

The system also includes a fusion channel gateway;

The terminal and the converged channel gateway establish an end-to-end two-way channel on the IP network, and are respectively end devices of the two-way channel;

The IP/DVB gateway and the cable television network constitute a one-way communication channel from the converged channel gateway to the terminal;

The terminal sends the uplink IP packet to the fusion channel gateway through the IP network two-way communication channel, and the fusion channel gateway obtains the uplink IP packet from the IP network, and then checks whether there is a mapping in the address mapping table record; if the mapping record does not exist, you must first allocate an unused port as the mapping port, and save the address mapping record in the address mapping table; then perform address translation on the upstream IP packet, and replace it with the address of the fusion channel gateway and the mapping port source address and source port in the original upstream IP packet, and then the converted upstream IP packet is sent to the IP network; if the mapping record exists, then the fusion channel gateway directly performs address translation on the upstream IP packet to integrate the channel gateway Replace the source address and source port in the uplink IP packet with the address and mapped port, and then send the converted uplink IP packet to the IP network; the fusion channel gateway receives the response from the IP network For the downlink IP packet, query the address mapping table to obtain the IP address and port of the terminal, perform address translation on the received downlink IP packet, and replace the destination address and destination port of the downlink IP packet with the source address and source port of the uplink IP packet sent by the terminal; The converged channel gateway passes the converted downlink IP packets through the two-way channel of the IP network, or forms a one-way communication channel from the converged channel gateway to the terminal via the IP/DVB gateway and the cable TV network, or passes through the two-way communication channel at the same time and the one-way communication channel sent by the terminal.

The terminal and the converged channel gateway are in different IP subnets.

The IP network/cable TV network adopts separate physical lines, including: IP network and cable TV network in ADSL access mode.

The IP network/cable TV network is combined into the same physical line through frequency division multiplexing, including: an IP bidirectional network realized by CMTS and CM based on Docsis technology.

A QAM modulator is connected in series behind the RF transmitter, and the RF transmitter sends a signal to the QAM modulator, and the QAM modulator sends the signal to the cable TV network after multiplexing the signal with other signals; Wherein, other signals include: analog TV signal, digital TV signal.

The two-way communication channel adopts IP tunnel or virtual private network.

The terminal is a dual-mode digital set-top box terminal.

A broadband data communication method for merging an IP network and a cable television network, the specific steps of the method are as follows:

Step 1) after the terminal is started, establish an end-to-end bidirectional communication channel with the fusion channel gateway through the IP network, and simultaneously obtain the frequency point, symbol rate, modulation mode, transmission stream PID, program number parameter;

Step 2): The terminal sends the uplink IP packet to the fusion channel gateway through the two-way communication channel;

Step 3): The fusion channel gateway obtains the upstream IP packet from the IP network, and then checks whether there is a mapping record in the address mapping table; if the mapping record does not exist, an unused port will be allocated as a mapping port first , and save the address mapping record in the address mapping table; then perform address translation on the uplink IP packet, replace the source address and source port in the original uplink IP packet with the address and mapped port of the fusion channel gateway, and then convert the converted uplink IP The packet is sent to the IP network; if the mapping record exists, then the fusion channel gateway performs address translation on the upstream IP packet, and replaces the source address and source port in the upstream IP packet with the address of the fusion channel gateway and the mapped port, and then, the The converted uplink IP packet is sent to the IP network;

Step 4): the converged channel gateway receives the corresponding downlink IP packet from the IP network, queries the address mapping table to obtain the IP address and port of the terminal, converts the address of the received downlink IP packet, and sends it to the terminal The source address and source port of the uplink IP packet replace the destination address and destination port of the downlink IP packet;

Step 5): the converged channel gateway converts the converted downlink IP packet to the unit of the terminal through the two-way communication channel, or through the described converged channel gateway formed by the IP/DVB gateway and the cable television network. The terminal is sent to the communication channel, or through the two-way communication channel and the one-way communication channel at the same time.

In the step 1), the way for the terminal to obtain the frequency point, symbol rate, modulation method, transport stream PID, and program number parameters is to obtain through the configuration file or send by the converged channel gateway through the IP network.

In the described step 5), the downlink IP packet converted by the gateway of the fusion channel is encapsulated according to the DVB data broadcasting standard to form an MPEG-TS packet, and then M MPEG-TS packets are encapsulated as a UDP packet, and the UDP packet Send to the IP/DVB gateway through the IP network, the IP/DVB gateway converts the transmission stream into a baseband signal, and modulates it to the allocated frequency point, and passes through the RF signal of the IP/DVB gateway The transmitter sends to the cable TV network, and the terminal receives the signal through the demodulator and decapsulates it, so as to obtain the downlink IP packet; where, M∈[1,7].

The advantage of the present invention is that the present invention makes full use of the network bandwidth resources of the two-way IP network and the cable TV network, and can realize asymmetric bandwidth data communication in the environment where the two-way IP network and the cable TV one-way broadcast network coexist; The integrated channel gateway and the integrated channel gateway are the end devices of the two-way communication channel of the IP network. The integrated channel gateway can be flexibly deployed, and the work of encapsulating audio and video content into MPEG-TS transport streams is completed by the integrated channel gateway, which reduces development and provides two-way interaction. business difficulty.

Description of drawings

Fig. 1 is a VOD service system structural diagram in the coexistence environment of IP network and cable TV network;

Fig. 2 is the structure diagram of the broadband data communication system of fusion IP network and cable television network that the present invention proposes;

Fig. 3 is a system structure diagram of a terminal accessing a website proposed by the present invention;

Fig. 4 is the encapsulation format diagram of the uplink IP packet sent by the terminal to the converged channel gateway proposed by the present invention;

Figure 5 is an address mapping table;

Fig. 6 is the encapsulation format diagram of the upstream IP packet sent to the website by the fusion channel gateway proposed by the present invention;

Fig. 7 is the encapsulation format diagram of the downlink IP packet that the website that the present invention proposes sends to the fusion channel gateway;

FIG. 8 is a diagram of the encapsulation format of the downlink IP packet sent to the terminal through the bidirectional communication channel by the fusion channel gateway proposed by the present invention.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

The invention provides a broadband data communication system and method for merging IP network and cable TV network.

The structure diagram of the broadband data communication system of the fusion of IP network and cable TV network proposed by the present invention is shown in Figure 2, and the system includes IP network, IP/DVB gateway, cable TV network, fusion channel gateway and terminal components.

The terminal and the converged channel gateway establish an end-to-end two-way communication channel on the IP network, and are respectively end devices of the two-way communication channel. The IP/DVB gateway and the cable TV network constitute a one-way communication channel from the gateway to the terminal of the converged channel.

IP network and cable TV network can be separate physical lines, such as IP network and cable TV network in ADSL access mode; they can also be combined into the same physical line through frequency division multiplexing, such as CMTS and CM based on Docsis technology IP bidirectional network.

The IP/DVB gateway is responsible for receiving the MPEG-TS transmission stream from the IP network, converting the transmission stream into a baseband signal, modulating it to a frequency point, and sending it to the cable TV network through the RF transmitter of the IP/DVB gateway.

A QAM modulator can be connected in series behind the RF transmitter of the IP/DVB gateway. The RF transmitter of the IP/DVB gateway sends the signal to the QAM modulator. The QAM modulator multiplexes the signal with other signals and then multiplexes the multiplexed signal. sent to the cable television network.

Adopt the equipment that can not only receive DVB data broadcast from the cable TV network but also can access IP network. For example, the dual-mode digital set-top box terminal can receive DVB data broadcast, and there is also an RJ45 interface connected to an ADSL modem through a twisted pair to realize IP access.

The fusion channel gateway receives the uplink IP packet of the terminal from the IP network, performs address translation, and sends the converted uplink IP packet to the IP network; receives the corresponding downlink IP packet from the IP network, performs address translation, and finally the fusion channel gateway Pass the converted downlink IP packet through a two-way communication channel, or through the one-way communication channel between the integrated channel gateway formed by the IP/DVB gateway and the cable television network to the terminal, or simultaneously through the two-way communication channel and the one-way communication channel sends the terminal

Two-way communication channel adopts IP tunnel or virtual private network.

The system structure diagram of the terminal access website proposed by the present invention is shown in FIG. 3 . The system is composed of a website, a fusion channel gateway, an IP network, an IP/DVB gateway, a cable TV network and a terminal.

The parameters are set as follows:

(1) The website provides services based on the HTTP application protocol, the IP address is 211.147.6.148, and the listening port is 80;

(2) The IP address of the fusion channel gateway is 210.75.225.233;

(3) The IP address of the IP/DVB gateway is 159.226.219.5;

(4) The terminal is connected to the IP network by ADSL dial-up, and its IP address is 10.0.0.100;

(5) Website, integrated channel gateway, IP/DVB gateway are connected to IP network; IP/DVB gateway is connected to cable TV network;

(6) The terminal is connected to the IP network and the cable TV network at the same time.

After the terminal is started, it establishes an IP tunnel with the converged channel gateway, and obtains parameters such as frequency point, symbol rate, modulation mode, transport stream PID, and program number at the same time. There are many ways for the terminal to obtain the above parameters, for example, it can be obtained through a configuration file, and it can be sent to the terminal by the converged channel gateway through an IP tunnel.

The steps for the terminal to access the website are as follows:

(1) The terminal sends the original uplink IP packet to the converged channel gateway through the IP tunnel.

The encapsulation format diagram of the uplink IP packet sent by the terminal to the converged channel gateway proposed by the present invention is shown in 4. The source address of the inner uplink IP packet is 10.0.0.100, the source port is 2799, the destination address is 211.147.6.148, and the destination port is 80.

(2) After the fusion channel gateway receives the upstream IP packet, it obtains the inner layer upstream IP packet, checks whether there is a mapping record in the address mapping table, if not, allocates an unused port as a mapping port, and saves it in the address mapping table Address mapping records, and then perform address translation on the inner layer uplink IP packet, replace the source address and source port in the original uplink IP packet with the address and mapped port of the fusion channel gateway, and then send the converted uplink IP packet to the IP network.

The address mapping table is shown in Figure 5. Among them, the mapped port is 13478, and the converted upstream IP packet encapsulation format is shown in Figure 6. The source address of the converted upstream IP packet is 210.75.225.233, the source port is 13478, the destination address is 211.147.6.148, and the destination port is 80 .

(3) The IP network routes the converted uplink IP packet to the website, and the website receives the IP packet from the fusion channel gateway, and sends the corresponding downlink IP packet to the IP network.

The website that the present invention proposes sends to the downlink IP packet encapsulation format diagram of the fusion channel gateway, as shown in Figure 7, the source address of the downlink IP packet is 211.147.6.148, and the source port is 80, and the destination address is 210.75.225.233, and the destination port is 13478.

(4) The IP network routes the downlink IP packets to the fusion channel gateway, and the fusion channel gateway receives the corresponding downlink IP packets, queries the address mapping table to obtain the IP address and port of the terminal, performs address translation on the received downlink IP packets, and uses the terminal The source address and source port of the inner layer uplink IP packet sent replace the destination address and destination port of the downlink IP packet.

The source address of the converted IP packet is 211.147.6.148, the source port is 80, the destination address is 10.0.0.100, and the destination port is 2799.

(5) The integrated channel gateway sends the converted downlink IP packet to the terminal through the IP tunnel or the one-way communication channel, or sends it to the terminal through the IP tunnel and the one-way communication channel at the same time.

The encapsulation format diagram of the downlink IP packet sent by the converged channel gateway to the terminal through the bidirectional communication channel is shown in FIG. 8 . The source address of the downlink IP packet converted by the inner layer is 211.147.6.148, the source port is 80, the destination address is 10.0.0.100, and the destination port is 2799.

The fusion channel gateway encapsulates the converted downlink IP packets into MPE multi-protocol encapsulation according to the DVB data broadcasting standard, and encapsulates the MPE multi-protocols into MPEG-TS packets, then encapsulates M MPEG-TS packets into UDP packets, and converts the UDP packets into MPEG-TS packets. Send it to the IP/DVB gateway through the IP network, the IP/DVB gateway converts the transmission stream into a baseband signal, and modulates it to the allocated frequency point, and sends it to the cable TV network through the RF transmitter of the IP/DVB gateway, and the terminal passes through The demodulator receives the signal, decapsulates it, and obtains the downlink IP packet. where M ∈ [1, 7].

A system and method for realizing broadband data communication by integrating the two-way communication channel of IP network and the one-way communication channel of cable TV network according to the present invention, in the above-mentioned embodiment, the terminal visits the website as an example to introduce, and other two-way data communication Processing method and principle are identical, do not repeat introduction here; Use IP tunnel as two-way communication channel in the embodiment, the two-way communication channel that other technology realizes all belong to the scope of protection of the present invention; In the embodiment, the terminal takes the ADSL access mode as an example, other as long as Logically, both the IP network and the cable television network belong to the scope of protection of the present invention, and will not be introduced one by one here.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than limit them. Although the present invention has been described in detail with reference to the embodiments, those skilled in the art should understand that modifications or equivalent replacements to the technical solutions of the present invention do not depart from the spirit and scope of the technical solutions of the present invention, and all of them should be included in the scope of the present invention. within the scope of the claims.

Claims (10)

1. A broadband data communication system integrating IP network and cable television network, the system comprising: IP network, IP/DVB gateway, cable television network and terminal; The IP/DVB gateway is responsible for receiving the MPEG-TS transport stream from the IP network, converting the MPEG-TS transport stream into a baseband signal, and modulating it to a frequency point, passing through the IP/DVB gateway The RF transmitter is sent to said cable television network; Described terminal adopts the equipment that can not only receive DVB data broadcast from cable TV network but also can access IP network; The IP/DVB gateway is connected to the terminal through a cable TV network; It is characterized in that, The system also includes a fusion channel gateway; The terminal and the converged channel gateway establish an end-to-end two-way communication channel on the IP network, and are respectively end devices of the two-way communication channel; The IP/DVB gateway and the cable television network constitute a one-way communication channel from the converged channel gateway to the terminal; The terminal sends the uplink IP packet to the fusion channel gateway through the IP network two-way communication channel, and the fusion channel gateway obtains the uplink IP packet from the IP network, and then checks whether there is a mapping in the address mapping table record; if the mapping record does not exist, you must first allocate an unused port as the mapping port, and save the address mapping record in the address mapping table; then perform address translation on the upstream IP packet, and replace it with the address of the fusion channel gateway and the mapping port source address and source port in the original upstream IP packet, and then the converted upstream IP packet is sent to the IP network; if the mapping record exists, then the fusion channel gateway directly performs address translation on the upstream IP packet; the fusion The channel gateway receives the corresponding downlink IP packet from the IP network, queries the address mapping table to obtain the IP address and port of the terminal, performs address translation on the received downlink IP packet, and uses the source address and source address of the uplink IP packet sent by the terminal The port replaces the destination address and the destination port of the downlink IP packet; the downlink IP packet converted by the converged channel gateway is passed through the IP network two-way communication channel, or forms the converged channel gateway through the described IP/DVB gateway and cable television network to The one-way communication channel of the terminal, or through the two-way communication channel and the one-way communication channel at the same time to the terminal. 2. The broadband data communication system of merging IP network and cable TV network according to claim 1, characterized in that, said terminal is in a different IP subnet from said merging channel gateway. 3. the broadband data communication system of fusion IP network and cable television network according to claim 1 is characterized in that, described IP network/cable television network adopts the physical circuit of separation, comprises: the IP network of ADSL access mode and wired TV internet. 4. The broadband data communication system of merging IP network and cable television network according to claim 1, characterized in that, said IP network/cable television network is combined into the same physical line by frequency division multiplexing, comprising: based on Docsis The technology of CMTS and CM realizes the IP bidirectional network. 5. the broadband data communication system of fusion IP network and cable television network according to claim 1, is characterized in that, QAM modulator is connected in series behind described RF sender, and RF sender sends signal to described QAM A modulator, the QAM modulator multiplexes the signal with other signals and sends it to the cable TV network; wherein, the other signals include: analog TV signals and digital TV signals. 6. The broadband data communication system of merging IP network and cable TV network according to claim 1, characterized in that, said two-way communication channel adopts IP tunnel or virtual private network. 7. The broadband data communication system merging IP network and cable TV network according to claim 1, characterized in that, said terminal adopts a dual-mode digital set-top box terminal. 8. A kind of communication method that realizes the broadband data communication system of fusion IP network and cable TV network as claimed in claim 1, the concrete steps of this method: Step 1) After the terminal is started, establish an end-to-end two-way communication channel with the converged channel gateway through the IP network, and at the same time, the terminal obtains the frequency point, symbol rate, modulation mode, transmission stream PID, program number parameter; Step 2): The terminal sends the uplink IP packet to the converged channel gateway through the two-way communication channel; Step 3): The converged channel gateway obtains the uplink IP packet from the IP network, and then checks whether there is a mapping record in the address mapping table; if the mapping record does not exist, first assign an unused port as the mapping port , and save the address mapping record in the address mapping table; then perform address translation on the uplink IP packet, replace the source address and source port in the original uplink IP packet with the address and mapped port of the fusion channel gateway, and then convert the converted uplink IP The packet is sent to the IP network; if the mapping record exists, then the fusion channel gateway performs address translation on the upstream IP packet, and replaces the source address and source port in the upstream IP packet with the address of the fusion channel gateway and the mapped port, and then, the The converted uplink IP packet is sent to the IP network; Step 4): The converged channel gateway receives the corresponding downlink IP packet from the IP network, queries the address mapping table to obtain the IP address and port of the terminal, performs address translation on the received downlink IP packet, and sends it to the terminal The source address and source port of the uplink IP packet replace the destination address and destination port of the downlink IP packet; Step 5): The converged channel gateway transfers the converted downlink IP packet to the unit of the terminal through the two-way communication channel, or through the converged channel gateway formed by the IP/DVB gateway and the cable television network. to the communication channel, or to the terminal through the two-way communication channel and the one-way communication channel at the same time. 9. The broadband data communication method for integrating IP network and cable TV network according to claim 8, characterized in that in step 1), the terminal obtains the frequency point, symbol rate, modulation method, transport stream PID, program The number parameter is obtained through configuration files or sent by the converged channel gateway through the IP network. 10. The broadband data communication method for merging IP network and cable television network according to claim 8, characterized in that, in the step 5), the merging channel gateway converts the converted downlink IP packet according to DVB data Broadcast standard encapsulation, form MPEG-TS bag, then M MPEG-TS bag is encapsulated into UDP bag, UDP bag is sent to described IP/DVB gateway through described IP network, described IP/DVB gateway will The transport stream is converted into a baseband signal and modulated to the assigned frequency point, and sent to the cable TV network through the RF transmitter of the IP/DVB gateway, and the terminal receives the signal through the demodulator and decapsulates it , so as to obtain the downlink IP packet; among them, M∈[1,7].

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