KR20090100943A - Cable modem and distribution center for providing internet service and broadcasting service, and method for providing service thereof - Google Patents

Abstract

PURPOSE: A cable modem and a distribution center for providing an internet service and a broadcasting service, and a service providing method thereof are provided to supply a broadcasting service by using a channel different from a channel for an internet service, thereby obtaining a sufficient bandwidth for a broadcasting service. CONSTITUTION: A cable modem(130) is connected to a distribution center(200) which provides an internet service and a broadcasting service. The cable modem includes a subscriber checking unit and a channel setting unit. The subscriber checking unit checks whether a service requester is a broadcasting service subscriber. The channel setting unit sets a partial RF channel of a downward RF channel with which RF(Radio Frequency) channels are combined as an RF channel for broadcasting if the service requester is a broadcasting service subscriber. The channel setting unit sets the remaining partial RF channel as an RF channel for an internet service. If the service requester is not a broadcasting service subscriber, all RF channels of a downward RF channel are set as a channel for an internet service.

Description

Cable modem and distribution center providing Internet service and broadcasting service and method of providing the service {CABLE MODEM AND DISTRIBUTION CENTER FOR PROVIDING INTERNET SERVICE AND BROADCASTING SERVICE, AND METHOD FOR PROVIDING SERVICE THEREOF}

The present invention relates to a cable modem and distribution center for providing Internet service and broadcast service, and a service providing method thereof.

Internet service providers install Cable Modem Termination System (CMTS) in distribution centers or telecommunication stations of cable television (hereinafter referred to as "TV") stations, and cable modems in subscriber premises It installs and connects CMTS and cable modem to cable TV network to provide internet service.

Recently, Internet service providers have been providing Internet protocol broadcasting (hereinafter referred to as "IP-TV") services by connecting a set-top box to a cable modem.

These CMTS and cable modems communicate using frequency bands not used in cable broadcasting. In this case, a frequency band not used in cable broadcasting is mainly used as a frequency band for Internet service.

In order to simultaneously provide IP-TV service in the Internet service of the cable TV network, a lot of bandwidth is required. However, since the existing Internet service uses only a part of the frequency band, there are many difficulties in providing an IP-TV service that must simultaneously provide a large number of broadcast channels.

The problem to be solved by the present invention is to provide a cable modem and distribution center and a service providing method thereof that can simultaneously provide Internet and broadcast services.

According to an embodiment of the present invention, there is provided a cable modem connected to a distribution center for providing Internet service and broadcast service. The cable modem includes a subscriber identification section and a channel setting section. The subscriber identification unit confirms whether the service requester is a broadcast service subscriber. When the service requester is the broadcast service subscriber, the channel setting unit sets some RF channels of the downlink RF channel combined with a plurality of radio frequency (RF) channels as a broadcasting RF channel and sets the remaining RF channels as the RF channel for internet service. If the service requester is not the broadcast service subscriber, all RF channels of the downlink RF channel are set to the Internet service channel.

According to another embodiment of the present invention, a distribution center for providing an Internet service and a broadcast service to a service requester through a cable modem is provided. The distribution center includes a receiver and a cable modem termination device. The receiving unit receives, from the cable modem, separation request information of a downlink RF channel to which a plurality of radio frequency (RF) channels are combined. The cable modem termination device provides Internet data to the cable modem using at least a part of the RF channel of the downlink RF channel according to whether the separation request information is received.

According to another embodiment of the present invention, a method for providing an Internet service and a broadcast service to a service requester through a cable modem is provided. The method may include determining whether to receive separation request information of a downlink RF channel to which a plurality of radio frequency (RF) channels are combined from the cable modem, and when receiving the separation request information, partial RF of the downlink RF channel. Providing the Internet service to the cable modem using a channel, providing the broadcast service to the cable modem using some remaining RF channels, and if the separation request information is not received, the plurality of RF channels. Providing the Internet service to the cable modem by using.

According to an embodiment of the present invention, since it is determined whether to separate the downlink RF channel combined with a plurality of channels according to whether or not the service requester is an IP-TV service subscriber, the Internet subscribers who are not IP-TV service subscribers can use the Internet at high speed. You can get services.

In addition, since the IP-TV service subscriber can receive the broadcast service using a channel different from the channel for the Internet service, it is possible to prevent the degradation of the Internet service and to secure sufficient bandwidth for the broadcast service.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention. Like parts are designated by like reference numerals throughout the specification.

Throughout the specification, when a part is said to "include" a certain component, it means that it can further include other components, without excluding the other components unless otherwise stated.

Now, a cable modem, a distribution center, and a service providing method for providing an Internet service and a broadcast service according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram of a cable network based service providing system according to an exemplary embodiment of the present invention, and FIG. 2 is a block diagram of a cable modem shown in FIG. 1.

As shown in FIG. 1, a cable network based service providing system includes a subscriber premises device 100 and a distribution center 200 connected thereto via a cable network 30.

The subscriber premises device 100 includes a subscriber station 110, a set top box 120 and a cable modem 130.

The subscriber station 110 is a terminal that provides a service to a service requester, and may include a TV 110a and a computer (hereinafter, referred to as a “PC”) 110b in an embodiment of the present invention. The service requester may be subscribed to the Internet service and the IP-TV service together or subscribed to only the Internet service. The PC 110b provides the service requester with Internet data received from the cable modem 130, and when the service requester is subscribed to the IP-TV service (hereinafter, “the service requester subscribed to the IP-TV service” is referred to as “IP”). -TV service subscriber.) The TV 110a provides the IP-TV service subscriber with the IP-TV data received from the set-top box 120.

The set-top box 120 delivers IP-TV data of the IP-TV broadcasting channel received from the cable modem 130 to the TV 110a, and requests the subscriber of the IP-TV service such as changing the IP-TV broadcasting channel. The control signal is converted and transmitted to the cable modem 130.

The cable modem 130 receives the Internet data and the IP-TV data from the distribution center 200 through the cable network 30, transfers the Internet data to the PC 130a, and transmits the IP-TV data to the set-top box 120. To pass.

In addition, the cable modem 130 according to an embodiment of the present invention is a downlink RF is formed by combining a plurality of radio frequency (hereinafter referred to as "RF") channel according to whether the service requester is an IP-TV service subscriber or not. Determine whether the channel is separated.

As shown in FIG. 2, the cable modem 130 includes a subscriber identification unit 131, a channel setter 132, a transmitter 133, a receiver 134, a data controller 135, and a channel frequency controller 136. It includes.

The subscriber identification unit 131 confirms whether the service requester is an IP-TV service subscriber.

If the service requester is not an IP-TV service subscriber, the channel setting unit 132 sets all RF channels of the downlink RF channel as RF channels for Internet services. On the other hand, when the service requester is an IP-TV service subscriber, the channel setting unit 132 sets some RF channels of the downlink RF channel as RF channels for Internet services, and sets some other RF channels as RF channels for IP-TV services. do.

In addition, the channel setting unit 132 transmits the set downlink RF channel information to the transmitter 133 and requests the distribution center 200 to separate the downlink RF channel.

The transmitting unit 133 transmits the downlink RF channel information and control signals corresponding to the request of the IP-TV service subscriber to the distribution center 200 through the cable network 30, and transmits Internet data and IP-TV data to the PC (each). 110a) and set-top box 120.

The receiver 134 receives the Internet data, the IP-TV data and the RF channel information for the IP-TV service channel from the distribution center 200 through the cable network 30.

The data controller 135 demodulates the Internet data and the IP-TV data received by the receiver 134 and transmits the demodulated data to the transmitter 133.

The channel frequency controller 136 sets the frequency of the RF channel for the IP-TV service according to the channel information for the IP-TV service for the IP-TV broadcasting channel.

Referring back to FIG. 1, the distribution center 200 may include a dynamic host configuration protocol (hereinafter referred to as “DHCP”) server 210, a switch 220, a CMTS 230, a receiver 240, Channel server 250, signal modulator 260, cable combiner 270, and transmitter 280.

The DHCP server 210 assigns an Internet Protocol (IP) address to Internet subscribers connecting to use the Internet.

The switch 220 is connected to the Internet network 10 and the IP-TV network 20, and transfers Internet data provided from the Internet network 10 to the CMTS 230, and from the IP-TV network 20. The IP-TV data of the provided IP-TV broadcasting channel is transmitted to the signal modulator 260 through the channel server 250.

The CMTS 230 modulates the Internet data with the address of the cable modem 130 using the allocated downlink RF channel and transmits it to the cable modem 130 through the cable combiner 270 and the transmitter 280, and the cable modem. The signal transmitted from the 130 is received through the receiver 240 and processed. In this case, the CMTS 230 may transmit the Internet data through some RF channels of the downlink RF channel or the Internet data through all the RF channels of the downlink RF channel according to the channel separation request from the cable modem 130. .

On the other hand, when the cable modem 130 transmits a channel separation request, the CMTS 230 transmits Internet data through some RF channels of the downlink RF channel.

The receiver 240 is connected to the cable network 30 and transmits a signal transmitted from the cable modem 130 to the CMTS 230 through the cable network 30.

 The channel server 250 manages downlink RF channel information, IP-TV broadcast channel information, and IP address information, and a signal that the cable modem 130 can recognize IP-TV data transmitted through the switch 220. The signal is converted into and transmitted to the signal modulator 260.

The signal modulator 260 modulates the IP-TV data into the frequency signal of the allocated downlink RF channel and outputs the signal to the cable combiner 270. In this case, a quadrature amplitude modulation (QAM) method may be used as the modulation method.

In addition, when the IP-TV service subscriber requests a specific IP-TV broadcasting channel, the channel server 250 may provide a downlink RF channel corresponding to the IP-TV broadcasting channel requested by the IP-TV service subscriber through the cable modem 130. Information is sent to the signal modulator 260.

The signal modulator 260 provides downlink RF channel information to the cable modem 130 via the cable combiner 270 and the transmitter 280. Then, the cable modem 130 receives the IP-TV data through the RF channel corresponding to the received downlink RF channel information.

The cable combiner 270 combines the cable for Internet data received from the CMTS 230 and the cable for IP-TV data received from the signal modulator 260 and transmits the cable to the transmitter 280.

The transmitter 280 is connected to the cable network 30, and transmits the data combined in the cable combiner 270 to the cable network 30.

Meanwhile, the cable network 30 includes a transceiver 32 and a distributor 34. The transceiver 32 is located between the cable modem 100 and the distributor 32, and the distributor 34 is located between the transceiver 32 and the cable modem 130. The transceiver 32 and the distributor 34 transmit signals transmitted and received between the distribution center 200 and the cable modem 100 to the transmitter / receiver 240 and 280 or the cable modem 130.

As an example of the cable network 30, an optical coaxial mixed network may be applied. The optical coaxial mixed network is composed of an optical fiber and a coaxial cable. The optical coaxial mixed network is connected to the cable modem 130 of the subscriber premises device 100 by a coaxial cable. The receivers 240 and 280 are connected by an optical cable. When the optical coaxial mixed network is applied as the cable network 30, the receiver 240 of the distribution center 200 converts the received optical signal into an RF signal, and the transmitter 280 of the distribution center 200. Performs a function of converting the received RF signal into an optical signal. In addition, when an optical coaxial mixed network is applied as the cable network 30, the RF signal transmitted through the distributor 34 to the transceiver 32 of the cable network 30 is converted into an optical signal and transmitted from the transmitter 280. An outdoor optical network unit (ONU) for converting an optical signal into an RF signal may be used.

As described above, when the optical fiber coaxial mixed network is used as the cable network 30, a large amount of data (for example, the Internet, cable TV, and IP-TV) can be transmitted by using a bandwidth of a wide optical cable. It is easy to implement interactive service when watching TV as well as digital TV. In addition, it provides a high-speed Internet service and can provide a variety of multimedia services at high speed, and since the Internet can be used immediately at the same time the PC (110b) is turned on, there is no need for a separate connection process.

Meanwhile, in FIG. 1, Internet data and IP-TV data are transmitted to the cable modem 130 through the cable combiner 270, the transmitter 280, the transceiver 32, and the distributor 34, and the channel setting information and the subscriber's information. Control signals for the request are sent to the CMTS 230 through the distributor 34, the transceiver 32 and the receiver 240. Hereinafter, for convenience of description, the cable combiner 270, the transmitter 280, the transceiver 32, and the distributor 34 are referred to as downlink transmission paths, and the distributor 34, the transceiver 32, and the receiver 240 are uplink transmission paths. It is called.

Next, an operation of the cable network based service providing system according to an exemplary embodiment of the present invention will be described in detail with reference to FIGS. 3 to 5.

3 is a flowchart illustrating an online registration process between a CMTS and a cable modem according to an embodiment of the present invention.

As shown in Figure 3, when the power of the cable modem 130 is turned on (S310), the cable modem 130 automatically searches for the frequency of the up / down RF channel (S320).

The cable modem 130, which retrieves the frequency of the uplink / downlink RF channel, transmits an upstream channel descriptor (UCD) message, which includes data about an uplink RF channel, through the downlink transmission path. Received from the 230 (S330). The cable modem 130 transmits and receives data with the CMTS 230 using information included in the UCD message.

Next, the cable modem 130 transmits the level ranging message to the CMTS 230 through the uplink path while gradually increasing the level from the low level to the high level (S340). When the level of the cable modem 130 reaches an appropriate value, the CMTS 230 receives the level ranging message, and the CMTS 230 carries appropriate level value information and the like to transmit the level ranging response message to the cable modem 130. do.

The cable modem 130 modifies the level value transmitted upward according to the information included in the level ranging response message, and notifies the CMTS 230 that the level ranging response message has been received.

After retrieving the appropriate level value due to level ranging in this way, the cable modem 130 requests an IP address to the DHCP server 210 through the uplink path (S350), and the cable modem IP from the DHCP server 210. A response message including a Trivial File Transfer Protocol (TFTP) server IP, a Time Of Day (TOD) server IP, a configuration file, and the like is received (S360). At this time, the configuration file includes the configuration parameters of the cable modem 210 and the service subscriber information.

Then, the cable modem 130 first receives the current time information from the TOD server (S370), and downloads the configuration file (S380).

In this way, the cable modem 130 is in an online state registered with the CMTS 230.

4 is a flowchart illustrating a method of determining whether a downlink RF channel is separated in a cable modem according to an exemplary embodiment of the present invention.

As shown in FIG. 4, the cable modem 130 checks whether the service requester is an IP-TV service subscriber (S410-S420). In this case, the cable modem 130 may check whether the service requester is an IP-TV service subscriber from the service subscriber information included in the configuration file.

If the service requester is not an IP-TV service subscriber, the cable modem 130 sets all RF channels of the downlink RF channel as RF channels for Internet services (S430). Then, the CMTS 230 modulates the Internet data by using all RF channels of the downlink RF channel, and transmits the modulated Internet data to the cable modem 130 through the downlink transmission path (S460).

On the other hand, if the service requester is an IP-TV service subscriber, the cable modem 130 sets some RF channels of the downlink RF channels as RF channels for Internet services, and sets some other RF channels as RF channels for IP-TV services. (S440). Thereafter, the cable modem 130 transmits the set downlink RF channel information to the CMTS 230 and requests RF channel separation (S450). Then, the CMTS 230 modulates the Internet data by using some RF channels of the downlink RF channel, and transmits the modulated Internet data through the downlink transmission path.

The channel server 250 transmits the RF channel information and the IP-TV data corresponding to some remaining RF channels to transmit the IP-TV data to the signal modulator 260.

The signal modulator 260 modulates IP-TV data using the remaining RF channels corresponding to the RF channel information transmitted from the channel server 250, and modulates the modulated IP-TV data through a cable modem (downlink transmission path). 130) (S460).

The cable modem 130 demodulates the received IP-TV data, transmits the demodulated data to the set-top box 120, and demodulates the received Internet data to the PC 110b (S470).

5 is a flowchart illustrating a method of changing an IP-TV broadcasting channel according to an exemplary embodiment of the present invention.

As shown in FIG. 5, when the set-top box 120 receives a desired IP-TV broadcast channel request from an IP-TV service subscriber (S502), the Internet group management protocol including the requested IP-TV broadcast channel information (internet) A group management protocol (IGMP) message (hereinafter referred to as “IGMP JOIN message”) is generated and delivered to the cable modem 130 (S504-S506).

The cable modem 130 extracts the IGMP JOIN message and delivers the requested IP-TV broadcast channel information to the channel server 210 through the uplink path, the CMTS 230 and the switch 220 to the IP-TV broadcast channel. The corresponding downlink RF channel information is requested (S508-S514).

The channel server 210 searches for the downlink RF channel corresponding to the IP-TV broadcasting channel and transmits the searched downlink RF channel information to the signal modulator 260 (S516-S518).

The signal modulator 260 modulates the downlink RF channel information and transmits the downlink RF channel information to the cable modem 130 through the downlink transmission path (S520-S524).

The cable modem 130 demodulates the downlink RF channel information to obtain downlink RF channel information (S526), and confirms whether the downlink RF channel corresponding to the obtained downlink RF channel information is the same as the downlink RF channel currently being used (S528). ). In this case, if the acquired downlink RF channel is the same as the downlink RF channel being used, the IP-TV data of the requested IP-TV broadcasting channel is demodulated and multicasted to the set-top box 120 (S530-S532).

On the other hand, if the downlink RF channel corresponding to the obtained downlink RF channel information is not the same as the current downlink RF channel, the cable modem 130 changes the frequency of the acquired downlink RF channel (S534).

Thereafter, the cable modem 130 demodulates the IP-TV data of the requested IP-TV broadcasting channel to the set-top box 120 (S536-S538).

The set top box 120 provides multicasted IP-TV data to the service requester via the TV 110a.

Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the present invention defined in the following claims are also provided. It belongs to the scope of rights.

1 is a block diagram of a cable network based service providing system according to an exemplary embodiment of the present invention.

FIG. 2 is a block diagram illustrating a cable modem shown in FIG. 1;

3 is a flowchart illustrating an online registration process between a CMTS and a cable modem according to an embodiment of the present invention.

4 is a flowchart illustrating a method of determining whether to separate a downlink RF channel in a cable modem according to an embodiment of the present invention;

5 is a flowchart illustrating a method of changing an IP-TV broadcasting channel according to an exemplary embodiment of the present invention.

Claims (10)

In a cable modem connected to a distribution center that provides Internet and broadcast services, A subscriber identification unit for confirming whether the service requester is a subscriber of a broadcast service, and When the service requester is the broadcast service subscriber, some RF channels of the downlink RF channel to which a plurality of radio frequency (RF) channels are combined are set as broadcast RF channels, and some other RF channels are set as RF channels for Internet services. When the service requester is not the broadcast service subscriber, a channel setting unit for setting all RF channels of the downlink RF channel as the channel for the Internet service. Cable modem comprising a. The method of claim 1, A transmitter for transmitting the requested broadcast channel information requested by the service requester to the distribution center when the service requester is the broadcast service subscriber; A receiver for receiving broadcast RF channel information on the broadcast channel information from the distribution center, and A channel frequency controller configured to set a frequency of the broadcast RF channel according to the broadcast RF channel information Cable modem further comprising. The method of claim 1, A transmitter for transmitting the RF channel information set by the channel setting unit to the distribution center; Receiving unit for receiving the Internet data or broadcast data transmitted using the RF channel corresponding to the set RF channel information from the distribution center, And Data control unit for providing the Internet data or the broadcast data to the service requester Cable modem further comprising. A distribution center for providing Internet service and broadcasting service to a service requester through a cable modem, Receiving unit for receiving the separation request information of the downlink RF channel combined with a plurality of radio frequency (RF) channel from the cable modem, And A cable modem termination device for providing Internet data to the cable modem using at least a part of the RF channel of the downlink RF channel according to whether the separation request information is received. Distribution center comprising a. The method of claim 4, wherein The distribution center determines whether to receive the separation request information according to whether the broadcast service to the service requester subscription. The method of claim 5, The cable modem termination device provides the Internet data to the cable modem using all the RF channels of the downlink RF channel when the service requester is not the broadcast service subscriber, and when the service requester is the broadcast service subscriber. A distribution center for providing said internet data to said cable modem using some RF channel of a downstream RF channel. The method of claim 6, When the service requester is the broadcast service subscriber, the signal modulator for providing broadcast data to the cable modem by using the remaining part of the downlink RF channel Distribution center comprising more. The method according to any one of claims 4 to 7, A receiver for receiving broadcast channel information from the cable modem, and A channel server searching for a downlink RF channel corresponding to the broadcast channel information and providing downlink RF channel information to the cable modem Distribution center comprising more. In the method for providing a network service and a broadcast service to the service requester through a cable modem, Determining whether to receive separation request information of a downlink RF channel to which a plurality of radio frequency (RF) channels are combined, from the cable modem; When the separation request information is received, providing the Internet service to the cable modem using a part of the RF channel of the downlink RF channel, and providing the broadcast service to the cable modem using the remaining part of the RF channel, And If the separation request information is not received, providing the Internet service to the cable modem using the plurality of RF channels. Service providing method comprising a. The method of claim 9, Receiving broadcast channel information from the cable modem, Searching for a downlink RF channel corresponding to the broadcast channel information; and Providing information about the downlink RF channel to the cable modem Service providing method further comprising.

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