KR100243389B1 - Atm broadcasting service providing apparatus - Google Patents

Abstract

The present invention relates to a broadcast and ATM cell multiplexing device in an ATM access device which multiplexes ATM data transmitted from an ATM network and digital broadcast information provided from a digital headend, and transmits the same to a subscriber. Provides switching and forwarding functions of the provided ATM cells to subscribers through service channel access, and provides on-demand video service, existing internet service, and video phone service connected to ATM switching network through accessing ATM service from access device. At the same time, the access device provides a function of distributing and multiplexing digital broadcast data that has existed separately, thereby providing a service that combines existing ATM data and digital broadcast data through a broadcast and ATM multiplexing device. .

Description

Asynchronous transmission mode broadcasting service providing multiplexing device

According to the present invention, ATM data provided from an Asynchronous Transfer Mode (hereinafter referred to as ATM) network and 60 channels of MPEG-2 (6Mbps) digital broadcast data provided from a digital head-end are provided through one ATM channel. The present invention relates to a multiplexing device for providing broadcasting and ATM services for simultaneous provision to subscribers.

The ATM access device may communicate with an ATM switching network and a subscriber network based on synchronous transmission STM-1 (155 Mbps) or STM-4c (622 Mbps).

Through the access device, subscribers can be provided with high-speed services such as high-speed data service, video telephone, video on demand, search service, and the like.

In addition, MPEG-2 video developed through the development of multimedia signal processing technology provides better image quality than conventional analog TV in the 4-6Mbps band, thereby enabling digital multimedia information transmission.

However, until now, communication networks and broadcasting networks have evolved into separate networks, but in the ATM integrated access network, communication and broadcasting can be converged to provide a technology that can be transmitted to subscribers.

The ATM cells provided through the ATM network are 53 bytes, but in the broadcasting and ATM data transfer devices, a separate internal routing field is attached to the ATM cell header in front of the ATM cell header for switching processing in the system. Allows automatic routing of.

The MPEG-2 information provided from the digital headend consists of 188 bytes, and when it is mapped to the ATM Adaptation Layer 5 (hereinafter referred to as AAL5) protocol and transmitted to the subscriber, two consecutive MPEG-2 transports are performed. An 8-byte AAL5 trailer is added to the stream and configured as a 48-byte AAL5-PDU, and then an ATM header is added to the subscriber.

Broadcast information composed of MPEG-2 transport stream format is distributed to subscribers as well as media data and information on program list that subscribers can select channel. Since it serves to distribute to subscribers, it is possible to distribute an efficient broadcast service to many subscribers with limited bandwidth.

In the prior art, a broadcast service and a communication service are provided with separate networks, for example, cable TV networks, telephones, and communication networks exist separately.

Therefore, there is an advantage of providing various services by integrating broadcast data and communication data through the service access device to ATM subscribers, and providing efficient management of transmission bandwidth by supporting aggregation and multiplexing of downlink traffic in an asymmetric access network. The number of subscribers and services can be maximized.

In order to achieve the above, the present invention multiplexes an ATM service cell provided from an ATM network and a broadcast cell provided from an external broadcast headend in order to simultaneously provide broadcasting and communication services to a subscriber through an ATM subscriber access network device. The present invention provides an apparatus for transmitting broadcasting and communication information in an environment, and has a purpose of providing broadcasting and ATM services by increasing capacity of subscribers by concentrating and multiplexing upstream data because the upstream bandwidth is smaller than the downstream bandwidth due to the characteristics of an access network.

1 is a block diagram of an ATM broadcast service providing multiplexing device to which the present invention is applied;

2 is a detailed configuration diagram of a broadcast cell connection unit according to the present invention;

3 is a detailed configuration diagram of a routing cell downlink connection according to the present invention;

4 is a detailed configuration diagram of a broadcast and routing cell downlink processor according to the present invention;

5 is a detailed configuration diagram of a routing cell uplink multiplexing processor according to the present invention;

<Explanation of symbols for main parts of drawing>

110: broadcast cell connection

111: input buffer

112: broadcast cell input first-in first-out

113: broadcast cell processing signal generator

114: SOC verification unit

115: cell routing control unit

116: payload control unit

120: routing cell downward connection

121: input buffer

122: routing cell input first-in, first-out

123: routing cell processing signal generator

124: SOC verification unit

125: cell routing control unit

126: payload control unit

130: broadcast and routing cell down processing unit

131: broadcast cell connection

132: routing cell lower portion

133: first in first broadcast cell

134: routing cell first-in, first-out 1, 2, 3, 4

135: output selector

136: output routing signal generator

137: output buffer 1, 2, 3, 4

140: routing cell upward multiplexing processing unit

141: up switch connection

142: upward routing part

143: output buffer

144: first-in, first-out output

145: cell processing signal generator

146: payload control unit

147: SOC detector

148: first-in, first-out first, second, third, fourth

149: input buffer 1, 2, 3, 4

150: control processing unit

In order to achieve the above object, the present invention provides broadcast data from an ATM routing cell downlink, a digital headend, which communicates with the multiplexing device through a routing process of an access system and a switch of an access system. A broadcast cell routing unit for receiving and distributing, a broadcast cell and a routing cell downlink processor for routing to 4 subscriber ports after multiplexing the broadcast cell and the routing cell of the broadcast cell access unit, and multiplexing upstream routing cells provided from 4 subscriber ports After that, the routing cell multiplexing processing unit for transmitting to the switch, characterized in that it comprises a control processing unit for controlling and managing each processing unit of the apparatus through a processor.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram of an ATM broadcast service providing multiplexing apparatus to which the present invention is applied, and includes a broadcast cell access unit 110, a routing cell downlink processor 120, a broadcast and routing cell downlink processor 130, and a routing cell uplink multiplexer 140. ), And a control processing unit 150.

This device, which integrates and delivers ATM service and broadcast data to subscribers in an access network, receives a system clock and a RESET signal to provide all signals for processing ATM routing cells and broadcast cells to each processing block.

First, the broadcast cell access unit 110 maps the MPEG-2 transport stream, which is about 60 channels of broadcast data provided from a broadcast channel processing apparatus connected to an external digital headend and functions as a broadcast distribution, to AAL5-PDU in two units. The MPEG-2 transport stream divided into eight ATM cells is received in the same format as the routing cell.

The broadcast cell access unit 110 checks the header and the routing tag for the received broadcast cell and provides the same to the broadcast and routing cell downlink processor.

For ATM cell processing by mapping to AAL5-PDU for MPEG-2 transport stream, refer to Korean application 95-55917.

In order to transfer the ATM cell received from the ATM network to the subscriber port, the routing tag is added to the ATM cell so as to match the configuration of the switch used by the access device and provided to the downlink routing cell processor 120.

The downlink routing cell processor 120 determines whether a header and a routing tag are normally present with respect to a routing cell received at 600 Mbps, and provides four ports through the routing tag to the broadcast and routing cell downlink processor 130. .

The broadcast and routing cell downlink processor 130 receives and multiplexes the broadcast cell and the downlink routing cell from a higher level, and transmits the multiplexed broadcast cells to the subscriber block for access processing with an external optical termination device.

In the case of the uplink traffic, four uplink cells received from a subscriber access unit connected to an external optical termination device are received, and after processing the routing tag and the cell check for each uplink cell, the external uplink is transmitted to the ATM network. It provides a function of providing an uplink cell to the switch processing unit.

The control processor 150 including a processor and peripheral logic provides a signal for control and management necessary for the corresponding block, and performs various processes required for system management.

2 is a detailed configuration diagram of a broadcast cell access unit according to the present invention, and performs various functions by receiving system clock, RESET, and control signals required for system operation from the outside.

A broadcast cell processing signal is stored in the broadcast cell input first-in first-out (FIFO) 112 through an input buffer 111 that receives a broadcast cell received from an external broadcast cell providing unit. When the REQ signal is notified to the generator 113, the SOC and DATA notifying the start of the broadcast cell are output to the SOC detector 114 according to the RCK and REN signals for broadcast cell processing.

The SOC detector 114 checks the SOC to determine whether the input broadcast cell length is normal, and notifies the broadcast cell processing signal generator 113 of the test result as the SOC detection signal.

For example, when a broadcast cell of abnormal length is received, the next cell detected for cell synchronization is discarded and normal synchronization is found.

The normal broadcast cell is provided to the cell routing controller 115 that checks the routing tag of the broadcast cell, and controls the port to be output through the routing control signal with the DBTV_WEN signal.

In addition, when a broadcast cell having an abnormal tag is detected, the payload controller 116 is removed through an output control signal.

The payload control unit 116 manages the output of the payload through an output control signal when an abnormal SOC is detected, and provides a normal broadcast cell to the broadcast and routing cell downstream processor 130.

3 is a detailed configuration diagram of a routing cell downlink connection according to the present invention, and performs various functions by receiving a system clock, a RESET, and a control signal required for system operation from the outside.

Through the input buffer 121 for receiving a routing cell received from an external routing cell providing unit (switch) and storing it in the routing cell input FIFO 122, and if there is a received routing cell, the routing cell processing signal generator When the REQ signal is notified to 123, the SOC and DATA notifying the start of the routing cell are output to the SOC detector 124 according to the RCK and REN signals for routing cell processing.

The SOC detector 124 inspects the SOC to determine whether the input routing cell length is normal, and notifies the routing cell processing signal generator 123 of the test result as the SOC detection signal.

For example, when a routing cell of abnormal length is received, the next cell detected for cell synchronization is discarded and normal synchronization is found. The normal routing cell is provided to the cell routing control unit 125 that checks the routing tag of the routing cell. Since the lower function is subscribers having four ports, the port to be output through the inspection of the routing tag is controlled by the DNRT_WENs signal. .

The downstream broadcast and routing cell downlink processor 130 is provided through the DNRT_WENs signal.

When a routing cell having an abnormal tag is detected, the payload controller 126 is removed through an output control signal.

When the abnormal SOC is detected, the payload control unit 126 manages the output of the payload through an output control signal according to this function, and provides a normal routing cell to the broadcast and routing cell downstream processor 130. .

4 is a detailed configuration diagram of a broadcast and routing cell downlink processor according to the present invention, and performs system functions by receiving system clock, RESET, and control signals required for system operation from the outside.

First, the DBTV_DAT, which is a broadcast cell provided from the upper broadcast cell access unit 131, is stored in the broadcast cell FIFO 133 together with related control signals, and the routing cell DNRT_DATs provided to the upper routing cell downstream processing unit 130 are related controls. Together with the signal is stored in routing cells FIFO1-4 (134).

The signal indicating that there is data to be output is provided to the output selector 135 in the case of a broadcast cell, DBTV_REQ, and in the case of a routing cell, DNRT_REQs signals.

The output selector 135 determines whether a data output signal is present to determine whether to transmit a broadcast cell or a routing cell.

When determining the routing cell transmission, select only the FIFO with the routing cell to output the routing cell, and if there is no data, disable the output through the DNRT_OENs and DNRT_RENs signals.

The input / output control signal is outputted through the output routing signal generator 136 based on the control signal provided from the output selector 135, the output clock DBTV / DNRT_RCKs, the output enable signals DBTV_REN, DBTV_OEN, DNRT_RENS, and DNRT_OENs. The signal is output.

The output of the broadcast cell and the routing cell selects the broadcast cell DBTV_DDAT and the routing cell DNRT_DDATs from the output buffers (1, 2, 3, 4) 137 using the Tri-State of each FIFO to output the broadcast cell and the routing cell. .

For example, when the broadcast cell DBTV_DDAT is output, the output cell is selected through the DBTV_REQ signal. Accordingly, only the DBTV_REN and DBTV_OEN signals are active from the output routing signal generator 136, and the remaining routing cell output related signals are InActive. The DBTV_DDAT data is transmitted to the downstream subscriber side through the output buffers 1 to 4 137 together with the output signals DNRT_WCKs and DNRT_WENs signals.

If only the routing cell FIFO2 has data, the output is controlled so that only DNRT_REN2 and DNRT_OEN2 are active according to the DNRT_REQ2 signal, and the remaining signals are inactive.

5 is a detailed configuration diagram of a routing cell uplink multiplexing processor according to the present invention, and performs system functions by receiving a system clock, a RESET, and a control signal required for system operation from the outside.

Routing cells USR_UDATs and related signals USR_Uxxx are stored as uplink inputs FIFOs 1-4 148 through input buffers 1-4 149 from the subscriber side.

When the USR_REQs signal, which is an output request signal from the FIFO, is notified to the cell processing signal generator 145, the USR_RENs and USR_OENs signals, which are output signals, are selectively provided to the upstream input FIFOs, and the output uplinking cell is an SOC detector. After detecting the SOC informing the start of the cell at 147, the SOC detection signal notifying whether the cell is normal is notified to the cell processing signal generator 145. When the length of the uplinking cell is abnormal, the output control signal is output. The upstream cell outputted through the payload control unit 146 controls the output to the upstream output FIFO 144.

If there is transmission data from the upstream output FIFO 144, the cell processing signal generation unit 145 is notified through the UPRT_REQ signal. Accordingly, UPRT_DAT, which is an uplinking cell through the output buffer 143 together with the UPRT_WEN and UPRT_WCK signals, is related. It transmits the signal to the upper switch unit.

As described above, the present invention allows subscribers to receive a plurality of services on a single line by integrating various services using an access device to services provided separately from the existing broadcasting network and the communication network. In consideration of the asymmetric data rate of the on-demand service of the subscriber, the subscriber side can copy and transmit common data such as broadcast and downlink multiplexes and transmit and control it to the network. It can be effective.

Claims (5)

An apparatus for simultaneously providing broadcasting and communication services to a subscriber through an asynchronous transmission mode (ATM) subscriber access network device, Initializes the device through the system clock and RESET signal from the outside, and receives the broadcast cell provided from the upper broadcast processing function to determine the normality of the routing tag and the cell and transmits it to the broadcast and routing cell downstream processing unit. A broadcast cell connection processing unit; After receiving the ATM cell provided from the ATM network and adding a routing tag, receiving the downlink routing cell provided to transmit the same to the subscribers, determining whether the cell is normal and determining the routing tag to four subscriber ports. A routing cell downlink access unit performing a function of providing a downlink routing cell to a designated first-in first-out (FIFO); A broadcast and routing cell downlink processing unit configured to receive a broadcast cell and a downlink routing cell provided from an upper layer and perform output multiplexing on four subscriber lines; A routing cell uplink multiplexing processor configured to receive uplinking cells provided from the four subscriber lines, multiplex them, and transmit the multiplexed uplink cells to the upper switch unit; Asynchronous transmission mode (ATM) broadcast service providing multiplexing device comprising a control processing unit for controlling and managing each block of the multiplexing device that accommodates an ATM broadcast service. The method of claim 1, wherein the broadcast cell connection processing unit An input buffer unit for receiving a broadcast cell from an external broadcast access function; A broadcast cell input first-in, first-out unit for storing broadcast cells through an input buffer unit; A broadcast cell processing signal generator for generating a general signal for outputting the broadcast request signal of the broadcast cell after receiving the broadcast request signal; An SOC detector for determining whether a broadcast cell is normal since the SOC indicating the start of the broadcast cell output from the broadcast cell first-in-first-out unit is checked; A cell routing control processor for inspecting a routing field added to the broadcast cell and determining whether it is normal and controlling discarding of the broadcast cell when it is abnormal; A payload control processor configured to bypass the broadcast cell provided from the cell routing control unit when it is normal and control the output to discard the payload of the abnormal cell according to the SOC detection signal when the length of the cell is abnormally continued. Asynchronous transmission mode (ATM) broadcasting service providing multiplexing apparatus. The method of claim 1, wherein the routing cell connection processing unit An input buffer unit for receiving a routing cell from a routing cell connection function through an external network connection function and a switch; A routing cell input first-in, first-out unit for storing the downlink routing cell through the input buffer unit; A downlink routing cell processing signal generator for generating a general signal for outputting a downlink routing cell transmission request signal after receiving a downlink routing cell transmission request signal; An SOC detector for determining whether the downlink routing cell is normal by checking an SOC indicating the start of the downlink routing cell output from the downlink cell first-in, first-out unit; A cell routing control processor configured to check a routing field added to the downward routing cell to determine whether it is normal and to discard the downward routing cell in case of abnormality, and to control an output to a corresponding first-in, first-out port if it is normal; A payload control processor configured to bypass the down-routing cell provided from the cell routing controller when the cell is normal and control the output to discard the payload of the abnormal cell according to the SOC detection signal when the length of the cell is abnormally continued. Asynchronous transmission mode (ATM) broadcasting service providing multiplexing apparatus. The method of claim 1, wherein the broadcast and routing cell downstream processing unit A broadcast cell first-in, first-out unit for receiving a broadcast cell output from an upper broadcast cell connection unit and a downlink routing cell provided routed from a downlink cell connection unit for outputting an upper down routing cell; A routing cell first-in first-out storage configured to store a downlink routing cell outputted with a routing field value; An output selector configured to receive a transmission request signal DBTV_REQ signal from a broadcast cell first-in-first-out and a transmission request signal DNRT_REQs signal from routing cell FIFOs, and select a signal for determining which port to output; An output routing signal generator which provides an input / output signal xxx_RENs and xxx_OENs signals to a port to receive a control signal from the output selector and provides a downlink routing cell to an output buffer; And an output buffer unit configured to output a downlink subscriber cell (USR_DDATs) provided from a broadcast cell first-in first-out part and a routing cell FIFOs to an external subscriber port. The method of claim 1, wherein the routing cell up-multiplexing processing unit An input buffer unit for receiving uplink subscriber cells USR_UDATs from subscribers of four external downlink ports; An upstream input first-in first-out unit that stores uplink subscriber cells USR_UDATs through the input buffer unit; A cell processing signal generation unit receiving a signal USR_REQs indicating a data transmission request from an upstream first-in first-out unit and generating an output signal for multiplexing; An SOC detector for determining a start point and normal status of the uplink cell output according to the output signals USR_RENs and USR_RCKs provided from the cell processing signal generator; A payload controller for controlling an upstream output of the payload in accordance with an output control signal provided from the cell processing signal generator for the SOC detection; An upstream first-in, first-out unit that outputs an uplink cell according to an output control signal UPRT_RCK and UPRT_REN provided from a cell processing signal generator according to a transmission request signal of an uplink routing cell to an upstream external switch unit; Asynchronous transmission mode (ATM) broadcasting service providing multiplexing device, characterized in that the output buffer for outputting the outputted up-routing cell (UPRT_DAT) with a related signal.

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