KR100584354B1 - Passive optical network system based on ieee 1394 - Google Patents

Abstract

A passive optical communication network system based on IEEE 1394 is disclosed. The IEEE 1394-based passive optical communication network system configures a downlink time block having a constant length with respect to the time axis by using the IEEE 1394 format, which can include isochronous data and asynchronous packets in one cycle, and transmits downlink broadcasting. OLT, a plurality of ONUs receiving downlink time blocks transmitted from the OLT, detecting their data, transmitting the same to the subscriber, and configuring uplink time blocks having a predetermined length with respect to the time axis using the IEEE 1394 format; An uplink time block received through time division multiplexing is provided between an OLT and a plurality of ONUs in order to transmit downlink downlink blocks transmitted to the plurality of ONUs equally and to prevent collision of uplink time blocks transmitted from the ONU during uplink transmission. Has an optical splitter that transmits to the OLT.

Passive Optical Communication, IEEE 1394, Isochronous, Asynchronous, OLT, ONU

Description

Passive optical network system based on IEEE 1394 {PASSIVE OPTICAL NETWORK SYSTEM BASED ON IEEE 1394}             

1 is a diagram illustrating an uplink transmission structure of data in a gigabit Ethernet passive optical network system;

2 is a diagram illustrating a downlink transmission structure of data in a gigabit Ethernet passive optical communication network system;

3 is a diagram showing a basic data format of IEEE 1394 applied to the present invention;

4 is a block diagram showing a preferred embodiment of an IEEE 1394 based passive optical communication network system according to the present invention;

5 is a diagram illustrating an uplink transmission state of data between OLT and ONUs in an IEEE 1394-based passive optical communication network system of the present invention;

6 is a diagram illustrating a structure of a downlink time block of an IEEE 1394 based PON system according to the present invention;

7 illustrates a structure of an uplink time block of an IEEE 1394 based PON system according to the present invention; and

8 is a diagram illustrating a data flow between OLT and ONUs in an IEEE 1394 based PON system according to the present invention.

Explanation of symbols on the main parts of the drawings

100: OLT 120: optical splitter

140,142,144: ONU 160,162,164: User

The present invention relates to a passive optical network system (PON System), and more particularly, to a passive optical network system capable of performing optical communication based on the IEEE 1394 format.

The passive optical communication network system is a communication network system that transmits a signal to an end user through an optical cable network. Passive optical network systems consist of one optical line terminal (OLT) installed in a telecommunications company and multiple optical network units (ONUs) installed near subscribers. Typically, up to 32 ONUs can be connected to one OLT. have.

The passive optical network system can provide a user with a bandwidth of 622 Mbps downwards and 155 Mbps upwards in one standalone system, which can be allocated to multiple passive optical network system users. Passive optical network systems can also be used as trunks between large systems, such as cable TV systems, and residential Ethernet networks using nearby buildings or coaxial cables.

On the other hand, the OLT transmits a service for providing the service to the ONU through the optical fiber. The ONU receives the service provided from the OLT and transmits the signal to the end subscriber after signal processing. At this time, the ONU actively provides a service in response to a subscriber's request. Such a transmission system is called an active optical network.

Here, ONU, which is a transmission system of a service subscriber, is an end device of an optical communication network that provides a service interface to end users. The ONU accommodates Fiber To The Curb (FTTC), Fiber To The Building (FTTB), Fiber To The Floor (FTTF), Fiber To The Home (FTTH), and Fiber To The Office (FTTO). Accordingly, ONU implements high service accessibility to subscribers. ONU is connected to the subscriber and the cable for transmitting the analog signal transmitted from the subscriber and the OLT is connected to the optical facilities for transmitting and receiving optical signals to perform the function. Accordingly, the ONU performs photoelectric conversion for converting the optical signal transmitted from the OLT into an electrical signal and transmitting the signal to the subscriber, and all-optical conversion for converting the electrical signal transmitted from the subscriber into the optical signal and transmitting the optical signal to the OLT.

Currently, technologies for the Ethernet Passive Optical Network System and the Asynchronous Transfer Mode Passive Optical Network System are standardized and described in IEEE 802.3z and ITU-T G. 983.1.

1 is a diagram illustrating an uplink transmission structure of data in a Gigabit Ethernet Passive Optical Network System, and FIG. 2 is a diagram illustrating a downlink transmission structure of data in a Gigabit Ethernet Passive Optical Network System.

As shown, the passive optical communication network system has a structure in which one OLT 10 is connected in a tree structure by a plurality of ONUs 20, 22, and 24 and the optical splitter 15, and AON (Activity- It is a method to construct an effective subscriber network at a lower cost than an Opticla-Network) system.

In the form of a passive optical communication network (PON), an asynchronous transfer mode passive optical network (hereinafter referred to as ATM-PON) system was first developed and standardized. ATM-PON is an ATM cell ( Uplink and downlink transmission is performed in the form of a block in which cells are bundled in a predetermined size. On the other hand, the Ethernet Passive Optical Network System (hereinafter, referred to as E-PON) system transmits packets of different sizes into a block of a certain size. Thus, E-PON has a somewhat more complicated control structure than ATM-PON.

The uplink transmission of data will be described with reference to FIG. 1. In traffic control, in case of upstream, the respective data transmitted from the users 30, 32, and 34 are transmitted to each of the ONUs 20, 22, and 24. At this time, each of the ONUs 20, 22, and 24 transmits data transmitted from the users 30, 32, and 34 to the optical splitter 15 at the time when the transmission permission is allocated from the OLT 10. That is, each of the ONUs 20, 22, and 24 uplinks each received data in a time division multiplexing (TDM) scheme. Accordingly, in the optical splitter 15, data collision due to uplink transmission of data does not occur.

Referring to FIG. 2, downlink transmission of data will be described. In traffic control, in case of downstream, the OLT 10 broadcasts data for transmission to the ONUs 20, 22, and 24. When the data splitter 15 receives the data transmitted from the OLT 10, the optical splitter 15 distributes the received data to the respective ONUs 20, 22, and 24. Each of the ONUs 20, 22, and 24 detects data for transmission to the respective users 30, 32, and 34 from the data transmitted from the optical splitter 15, so that only the detected data is received by the users 30, 32 and 34, respectively.

At this time, since the OLT 10 transmits data to all ONUs 20, 22 and 24 during downlink transmission, the ONUs 20, 22 and 24 and OAM (Operations) for encryption and system state monitoring for data security. , Administration and Maintenance) messages. To this end, fields are provided in data blocks transmitted upward and downward so that messages can be exchanged at regular intervals.

In FIG. 1 and FIG. 2, the time slot of the ONU has an IEEE802.3 frame structure proposed by the Institute of Electrical and Electronics Engineers. Here the IEEE 802.3 frame has a header, a payload, and an error code. The header contains information related to the nature of the data, including the destination address of the actual data. The payload contains the actual data, and the error code contains the error recovery data used to recover from the destination an error that may occur while the data is being transmitted.

With the development of digital multimedia devices, more subscribers are required to ensure quality of service (QoS) and isochronous transmission in the wide area network (WAN) area including the subscriber network as well as in the home. This will require a lot of bandwidth. In order to meet these demands, Gigabit Ethernet has been recently proposed, which is relatively inexpensive and has high bandwidth, rather than ATM PON technology, which is expensive, has limited bandwidth, and has to segment IP packets into ATM cells. have.

However, Ethernet is basically a frame based protocol, which is designed to efficiently transmit variable packets, and is based on best effort transmission, not guarantee of quality of service (QoS). It is difficult to transmit real-time digital multimedia data such as VOD (Video on Demand) and general broadcasting through subscriber network.

In addition, in systems where uplink and downlink transmissions are mainly controlled on a time domain such as a PON system, frame-oriented Ethernet needs to map data in a certain time block. Therefore, in the case of E-PON, such a transmission method requires an additional control system to solve this problem and has a problem of acting as a factor preventing effective transmission.

SUMMARY OF THE INVENTION An object of the present invention for solving the above problems is to provide a passive optical communication network system suitable for transmitting data having a large capacity such as multimedia data and requiring real time transmission when transmitting and receiving data between OLT and ONUs.

Another object of the present invention is to provide a passive optical communication network system capable of high-speed communication at a lower cost while ensuring quality of service when transmitting and receiving data between OLT and ONUs.

It is still another object of the present invention to provide a passive optical communication network system capable of simultaneously transmitting data requiring isochronous transmission and asynchronous packet data such as IP packets.

According to the present invention, a downlink time block having a predetermined length with respect to a time axis is constructed using the IEEE 1394 format, which can include isochronous data and asynchronous packets in one cycle, and transmits downlink broadcasting. OLT; A plurality of ONUs that receive downlink time blocks transmitted from the OLT, detect their data, and transmit the same to the corresponding subscribers, and configure uplink time blocks having a predetermined length with respect to the time axis by using the IEEE 1394 format; And an uplink received between time-multiplexing in order to transmit a downlink time block, which is provided between an OLT and a plurality of ONUs, to the plurality of ONUs in the same way, and to prevent collision of an uplink time block transmitted from the ONU during uplink transmission. It is achieved by an IEEE 1394 based passive optical network system including an optical splitter that transmits a time block to an OLT.

Advantageously, said downlink time block comprises eight IEEE 1394 basic cycles having a length of 125 ms and having a total length of 2 ms. In addition, the downlink time block includes a grant frame for allocating uplink transmissions to a plurality of ONUs and OAM (Operations, Administration and Maintenance) frames for ONUs to transmit them to the OLT in the IEEE 1394 cycle. do.

Meanwhile, eight ONUs and channels can be formed per IEEE 1394 cycle, and 63 ONUs and channels can be formed in a downtime block of 2 ms overall. The downlink time block further includes a grant frame for allowing uplink isochronous transmission of multiple ONUs. Accordingly, upon receiving the grant frame corresponding to one of the plurality of ONUs, the ONU immediately inserts a real time stream into an uplink time division multiple time slot and transmits the uplink.

Preferably, the downlink time block is a grant for asynchronous packet transmission including information on the ID of a corresponding ONU for allowing uplink asynchronous packet transmission of a plurality of ONU and the size of time division multiple time slots for uplink transmission of the ONU. It also includes a frame. Accordingly, upon receiving the grant frame corresponding to one of the plurality of ONUs, upon receiving the grant frame for asynchronous packet transmission, the ONU receives uplink time-division multi-transmission by the size of the time-division multi-time slot transmitted from the OLT and then enters a standby state. Switch.

On the other hand, the OLT transmits a request access unit (RAU) grant frame to the plurality of ONUs even when there is no transmission request of the ONU, and the plurality of ONUs receive the RAU grant frames and uplink time-division multiplexing their RAU frames. Insert in time slot and transmit upstream.

Preferably, the uplink time block includes eight IEEE 1394 basic cycles having a length of 125 ms and a total length of 2 ms in order to balance media access control (MAC) operation during uplink and downlink transmissions. Has In addition, the uplink time block includes RAU (Request Access Unit) frame for transmitting uplink information such as traffic information necessary for band allocation, OAM frame response message, and uplink transmission information to OLT, such as queue information of the corresponding ONU. .

The RAU frame includes traffic information (QL: Queue Length) required for band allocation, including queue information of the ONU, a message (LCF: Laser Control Field, RXCF: Receiver Control Field), and a response for a downlink OAM frame. It consists of a message field into which information can be inserted.

According to the present invention, by applying the IEEE 1394 format as a data transmission format between the OLT and ONU, it is possible to simultaneously transmit isochronous transmission of real-time multimedia data and asynchronous packets such as IP. Accordingly, the present invention can be more usefully applied to a subscriber network for broadcasting communication convergence. In addition, the attributes of IEEE 1394, a low-cost solution, can be applied.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be noted that the same elements in the figures are represented by the same numerals wherever possible. In addition, detailed descriptions of well-known functions and configurations that may unnecessarily obscure the subject matter of the present invention will be omitted.

3 is a diagram illustrating a basic data format of IEEE 1394 applied to the present invention.

The IEEE 1394 format is emerging as the strongest technology as a standard for digital interface between multimedia devices in the home, and multimedia devices or computer products adopting the IEEE 1394 format have been increasing rapidly in recent years. The advantage of the IEEE 1394 format is that it enables high-speed serial communication of up to 3.2 Gbps with guaranteed quality of service (QoS) and low cost for multimedia transmission, and simultaneously transmits isochronous data and asynchronous packets such as IP based on TDM. It has a structure.

As shown, one cycle of the IEEE 1394 format is 125 μsec, and within one cycle, real-time isochronous data is channelized and assigned up to 80% of the time slots first. The remaining 20% is structured so that asynchronous packets such as IP packets can be allocated. In addition, an asynchronous packet having a destination address is positioned between the asynchronous packets because an ACK frame exists separately for arbitration with a node to receive. Here, isochronous data is data that is to be isochronously transmitted, and asynchronous packets are data that can be transmitted evenly, i.e., asynchronously. The isochronous data transmission interval has isochronous short gaps, and the asynchronous packet transmission interval has long intervals (Asynchronous long gaps).

4 is a block diagram illustrating a preferred embodiment of an IEEE 1394 based passive optical communication network system according to the present invention.

As shown, the IEEE 1394-based passive optical communication network system is equipped with a plurality of ONUs (140, 142, 144) around the OLT 100, which is a centralized station. More specifically, in the passive optical communication network system of the present embodiment, the OLT 100 and the optical distributor 120 are connected through optical fibers, and a plurality of ONUs 140, 142, and 144 are connected to the optical distributor 120, and each ONU 140, 142, 144 is connected. Has a structure in which the users 160, 162, and 164 are connected, respectively.

At this time, when the OLT 100 and the ONUs 140, 142, and 144 are connected, respectively, the basic attributes of the IEEE 1394 data format should be maintained with consideration of the corresponding distance and power budget. According to this characteristic, up to 63 ONUs may be mounted in the passive tree structure in the OLT 100.

ONU (140, 142, 144) is installed in the distribution boxes of buildings and apartment complexes or the entrance of a private housing complex, and has a function of connecting to the home network of a relatively short distance. The OLT 100 receives data from an upper network and distributes data to each ONU 140, 142, and 144 or accesses data from the ONU 140, 142, and 144. To this end, the OLT 100 performs at least a switching function of the data link layer, and the ONUs 140, 142, and 144 perform a switching function or a bridge function of the data link layer and the network layer.

In this embodiment, MAC (Media Access Control) is applied to meet the object of the present invention in a passive optical network network structure. In the case of using the MAC, the passive optical communication network of the present invention allocates the bandwidth for each ONU (140, 142, 144) to maintain a certain level or more to ensure the quality of service of the up and down data, and for the downlink data transmitted by broadcasting You can encrypt other ONUs so they can't read data from a particular ONU. In addition, the MAC optical passive network network transmits OAM (Operations, Administration and Maintenance) messages that can be transmitted to the OLT 100 and ONU (140, 142, 144) when a physical error in the communication occurs. In the passive optical communication network network using MAC, the distance from the optical distributor 120 to each ONU (140, 142, 144) after passing through the optical distributor 120 is different from the OLT 100 to each ONU (140, 142, 144). May differ from each other, and thus performs a ranging function that allows the ONU 140, 142, and 144 to maintain virtually the same distance so that data collision does not occur in the optical splitter 120 during time-division multiplexing (TDM) uplink transmission. do.

In this embodiment, in order to manage the MAC more effectively, it is bundled in a certain time block form. Accordingly, the IEEE1394 format of 125 kHz, which is composed of an isochronous channel and an asynchronous packet, is used as a basic cycle, and one block is configured to have a length of 2 ms. At this time, there are eight cycles in one block having a length of 2 ms. In this case, the reason why the length of the uplink time block is set to 2 ms is that the OLT 100 manages a maximum of 63 ONUs, and the overhead occupies a relatively high rate and the quality of service due to each ONU and message response interval. It is optimally set in consideration of efficient performance of QoS and OAM transmission functions.

In the IEEE 1394 based passive optical communication network system illustrated in FIG. 4, the data flow between the OLT 100 and the ONUs 140, 142, and 144 is shown for downlink transmission. The OLT 100 inserts a grant frame to be sent to each ONU 140, 142, and 144 based on the result of the ranging, and configures a downlink time block to transmit to the ONU 140, 142, and 144. Among the ONUs 140, 142, and 144, the ONU inserts its data into an uplink time slot and transmits the data to the OLT 100 as soon as the grant frame is transmitted from the OLT 100. In addition, the OLT 100 inserts a separate frame for operations, administration and maintenance (OAM) at regular time intervals. This is to place an encryption key required for encryption, a plug & play function of the ONUs 140, 142, and 144, various warning signals, and a message field for ranging.

FIG. 5 is a diagram illustrating an uplink transmission state of data between the OLT 100 and the ONUs 140, 142, and 144 in the IEEE 1394 based passive optical communication network system of the present invention. During uplink transmission, each ONU 140, 142, 144 inserts a request access unit (RAU) frame, which is status information including a transmission request message of the corresponding ONU, to configure an uplink time block. In the RAU frame, there is provided a message field for inserting traffic information necessary for bandwidth allocation, such as queue information of the ONU, contents responsive to the OAM frame transmitted during downlink transmission, and information necessary for transmission. The ONUs 140, 142, and 144 transmit the configured uplink time blocks to the OLT 100.

6 is a diagram illustrating a structure of a downlink time block of an IEEE 1394 based PON system according to the present invention.

As shown, the down time block consists of a 2 ms length consisting of eight cycles in which the IEEE 1394 1 cycle has a 125 ms length. In addition, a separate frame for transmitting operations, administration and maintenance (OAM) is inserted into the downlink time block at regular time intervals. This is to place an encryption key required for encryption, a play & plug function of the ONUs 140, 142, and 144, various warning signals, and a message field for ranging. In the figure, the OAM is inserted every two cycles.

In detail, the configuration of the IEEE 1394 1 cycle according to the downlink transmission, the IEEE 1394 1 cycle is composed of an isochronous channel and an asynchronous packet of 125 ㎲ec length. Here, a grant frame and an OAM to be sent to each ONU are inserted in the isochronous channel. The grant frame is composed of a header, a control message, and a grant. In addition, the grant frame further includes a respective ID for the ONU.

The OAM frame is composed of a header and "(ONU ID # + OAM Message field + Ranging field) x 8". That is, the OAM frame consists of an OAM-related message and a lazing-related message of the OLT 100. At this time, when the OLT 100 transmits the OAM frames to the ONUs 140, 142 and 144, the OAM frames are distributed by one frame per cycle within 2 ms so that one OAM frame manages eight ONUs in order to minimize delay. Insert and send Accordingly, one OAM frame is inserted every cycle, and eight OAM frames inserted at 2 ms manage and perform functions such as plug & play or ranging for eight ONUs, respectively.

Upon receiving the grant frame, the ONUs 140, 142, and 144 insert their data into the uplink time slot and transmit the data to the optical splitter 120.

The grant frame includes respective IDs for the 63 ONUs as described above. When the grant frames are received, the ONUs check their IDs from the received grant frame. If the grant frame is found to be its ID, the ONU starts inserting data in the uplink time slot. This operation continues until the next grant frame is received. After analyzing the received grant frame and determining that the ID is not its own ID, the ONU stops inserting data into an active time slot, and then the ONU starts inserting data into the time slot.

The above operation corresponds to the case of real-time stream data such as audio and video, and in the case of an asynchronous packet such as IP, the OLT 100 receives information of each ONU 140, 142, 144 and the corresponding information of each ONU 140, 142, 144. The size of uplink asynchronous packet data is specified within the grant frame and transmitted. Accordingly, in the case of an asynchronous packet, when a grant frame is received, the ONUs 140, 142, and 144 insert data only up to a predetermined time slot by the OLT 100, and transmit the data upward. Therefore, variable asynchronous packets can be efficiently processed.

7 is a diagram illustrating a structure of an uplink time block of an IEEE 1394 based PON system according to the present invention.

As shown, the uptime time block is composed of 2 ms long, consisting of eight cycles in which the IEEE 1394 1 cycle is 125 msec length. One cycle of IEEE 1394 consists of an isochronous channel and an asynchronous packet of 125 μs length. The OLT 140, 142, 144 inserts a request access unit (RAU) frame into an isochronous channel and transmits the uplink to the OLT 100. In the RAU frame, traffic information (QL: Queue Length) required for bandwidth allocation, such as ONU queue information, contents responding to the downstream OAM frame (LCF: Laser Control Field, RXCF: Receiver Control Field), and information necessary for transmission can be inserted. A message field or the like is provided.

Each ONU 140, 142, 144 inserts data into its own time slot, which is allowed according to the content and timing of the grant frame transmitted from the OLT 100. In the case of uplink transmission, each ONU 140, 142, 144 inserts state information such as its own traffic (LCF, RXCF) and transmission queue (QL) into the isochronous channel and continuously transmits it to the OLT 100. Therefore, the OLT 100 basically inserts and transmits the traffic to the ONU connecting the grant frame in the downlink so that the ONU 140, 142, and 144 can transmit at least the RAU frame even if there is no actual data to be transmitted. This is to inform the OLT 100 of ONU's own transmission queue and OAM-related messages continuously, to prepare for the next uplink transmission and to inform the OLT 100 of its status.

Therefore, the types of grant frames sent by the OLT 100 may be classified into three types: isochronous data, asynchronous data, and RAU. Meanwhile, in the present embodiment, the grant frame may be referred to as a transmission permission message allowing the OLT 100 to transmit data to the ONUs 140, 142, and 144, and the RAU includes a message requesting data transmission allocation of the ONUs 140, 142, and 144. It can be called status information.

8 is a view for explaining the data flow between the OLT 100 and ONU (140, 142, 144) in the IEEE 1394 based PON system according to the present invention.

As shown, the OLT 100 transmits each grant G to each ONU 140, 142, 144 at a set time. Each ONU 140, 142, 144 receives its grant G from a grant G sent from the OLT 100. Upon receiving the grant G, the ONU1 140 transmits data and status information RAU to the OLT 100. The ONU2 142 also receives the grant G transmitted from the OLT 100 and transmits data and status information (RAU) to the OLT 100 correspondingly. On the other hand, ONU3 (144) receives the grant (G) transmitted from the OLT (100), if there is no data to transmit correspondingly, only transmits the status information (RAU) to the OLT (100).

According to the present invention, by applying the IEEE 1394 format as a data transmission format between the OLT and ONU, it is possible to simultaneously transmit isochronous transmission of real-time multimedia data and asynchronous packets such as IP. Accordingly, the present invention can be more usefully applied to a subscriber network for broadcasting communication convergence. In addition, the attributes of IEEE 1394, a low-cost solution, can be applied.

In addition, by using the time base reference IEEE 1394 format based on MAC (Media Access Control), it is possible to cope with variable traffic more easily. Accordingly, the overall performance of the network can be further improved. In addition, by transmitting a grant, which is a transmission permission message in the OLT, and transmitting data as soon as the grant is received in the ONU, the performance of the overall network system can be improved as the permission process for data transmission is improved.

In the above, specific preferred embodiments of the present invention have been illustrated and described. However, the present invention is not limited to the above-described embodiment, and various modifications can be made by any person having ordinary skill in the art without departing from the gist of the present invention attached to the claims. will be.

Claims (18)

delete delete delete An OLT for constructing a downlink time block having a constant length with respect to the time axis by using the IEEE 1394 format, which can include isochronous data and asynchronous packets in one cycle, and transmit the downlink broadcast transmission; A plurality of ONUs which receive the downlink time block transmitted from the OLT, detect its data, and transmit the data to a corresponding subscriber; and configure uplink time blocks having a predetermined length with respect to a time axis by using the IEEE 1394 format and transmit uplink; And The down time blocks provided between the OLT and the plurality of ONUs are transmitted in the same way to the plurality of ONUs, and through time division multiplexing to prevent collision of up time blocks transmitted from the ONUs during uplink transmissions. An optical splitter for transmitting the received uplink time block to the OLT; The downlink time block includes eight IEEE 1394 basic cycles having a length of 125 ms, and has a total length of 2 ms. The downlink time block includes grant frames for allocating uplink transmissions to the plurality of ONUs, and operations, administration, and maintenance (OAM) frames for transmitting the same to the OLT by the ONU when the physical error occurs. Included in at least one, 8 ONUs and channels can be formed per IEEE 1394 cycle, and a total of 63 ONUs and channels can be formed in the down time block of the 2 ms overall IEEE 1394-based passive optical communication network system. The method of claim 4, wherein The downlink time block further includes a grant frame for allowing uplink isochronous transmission of the plurality of ONUs, The ONU receiving the grant frame corresponding to the one of the plurality of ONUs immediately inserts the real-time stream into the uplink time division multiple time slot and transmits the uplink immediately after receiving the grant frame. . The method of claim 4, wherein The downlink time block is a grant frame for asynchronous packet transmission including information on an ID of a corresponding ONU for allowing uplink asynchronous packet transmission of the plurality of ONUs and information on the size of a time division multiple time slot for uplink transmission of the ONU. More, Upon receiving the grant frame corresponding to the one of the plurality of ONUs, the corresponding ONU receives the grant frame for the asynchronous packet transmission and immediately receives the time division multiplexing by the size of the time division multiple time slot transmitted from the OLT. IEEE 1394 based passive optical network system, characterized in that for switching to. The method of claim 4, wherein The OLT transmits a request access unit (RAU) grant frame to the plurality of ONUs even when there is no request for transmission of the ONUs. The plurality of ONUs receive the RAU grant frames and at the same time insert their RAU frames into uplink time division multiple time slots and transmit uplink. The method of claim 4, wherein The uplink time block includes eight IEEE 1394 basic cycles having a length of 125 ms and a total length of 2 ms in order to maintain a balance of media access control (MAC) operations during uplink and downlink transmission. IEEE 1394 based passive optical communication network system. The method of claim 8, The uplink time block includes a RAU (Request Access Unit) frame for transmitting uplink information such as traffic information necessary for band allocation such as queue information of the corresponding ONU, a response message for the OAM frame, and uplink transmission information to the OLT. IEEE 1394 based passive optical communication network system, characterized in that. The method of claim 9, The RAU frame is, Traffic information (QL: Queue Length) required for band allocation including queue information of the ONU; A message responsive to the downlink OAM frame (LCF: Laser Control Field, RXCF: Receiver Control Field); And An IEEE 1394-based passive optical network system comprising at least one of a message field into which information necessary for transmission can be inserted. An OLT for constructing a downlink time block having a constant length with respect to the time axis by using the IEEE 1394 format, which can include isochronous data and asynchronous packets in one cycle, and transmit the downlink broadcast transmission; A plurality of ONUs which receive the downlink time blocks transmitted from the OLT, detect their data, and transmit the data to a corresponding subscriber; And And an optical splitter provided between the OLT and the plurality of ONUs and equally transmitting the downlink time blocks transmitted downward to the plurality of ONUs. The method of claim 11, The downlink time block includes eight IEEE 1394 basic cycles having a length of 125 ms, and has a total length of 2 ms. The method of claim 12, The downlink time block includes grant frames for allocating uplink transmissions to the plurality of ONUs, and operations, administration, and maintenance (OAM) frames for transmitting the same to the OLT by the ONU when the physical error occurs. IEEE 1394 based passive optical communication network system, characterized in that included in at least one. The method of claim 13, 8 ONUs and channels can be formed per IEEE 1394 cycle, and a total of 63 ONUs and channels can be formed in the down time block of the 2 ms overall IEEE 1394-based passive optical communication network system. A plurality of ONUs configured to uplink data transmitted from respective subscribers connected to provide a service by configuring an uplink time block having a predetermined length with respect to a time axis using the IEEE 1394 format; An optical splitter for time-division multiplexing the uplink time blocks to prevent collisions between uplink time blocks transmitted from the plurality of ONUs; And And an OLT for receiving the uplink time block transmitted from the optical splitter and analyzing the received uplink time block to perform a corresponding operation. The method of claim 15, The uplink time block includes eight IEEE 1394 basic cycles having a length of 125 ms and a total length of 2 ms in order to maintain a balance of media access control (MAC) operations during uplink and downlink transmission. IEEE 1394 based passive optical communication network system. The method of claim 16, The uplink time block includes a RAU (Request Access Unit) frame for transmitting uplink information such as traffic information necessary for band allocation such as queue information of the corresponding ONU, a response message for the OAM frame, and uplink transmission information to the OLT. IEEE 1394 based passive optical communication network system, characterized in that. The method of claim 17, The RAU frame is, Traffic information (QL: Queue Length) required for band allocation including queue information of the ONU; A message responsive to the downlink OAM frame (LCF: Laser Control Field, RXCF: Receiver Control Field); And An IEEE 1394-based passive optical network system comprising at least one of a message field into which information necessary for transmission can be inserted.

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