JP2008072534A - Pon system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a PON system flexibly adapted to PON upgrade at various future steps with an existing optical fiber infrastructure. <P>SOLUTION: When entry information, such as a receivable wave/transmission speed or a transmittable wave/transmission speed on a new or upgraded subscriber terminal device (ONU) is registered in the PON system of the subscriber terminal device (ONU), it is notified from the existing subscriber terminal device (ONU) to a station terminal device (OLT) through PON control frames. Based on the entry information notified from the subscriber terminal device (ONU), the station terminal device (OLT) determines a structure of the PON system including the wave/transmission speed of transmission or receiving signals for the subscriber terminal device (ONU), and then notifies the subscriber terminal device (ONU) of the structure information on the determined PON system. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a PON (Passive Optical Network) system, and more particularly to a PON system capable of performing flexible migration from an existing system.

  Since the PON system is a transmission method in which a single optical fiber is branched by an optical splitter and shared by a plurality of users, it is possible to keep station-side equipment shared and optical fiber costs low. T. G. 983 series B-PON and G. The 984 series G-PON has been standardized.

  In addition, with the spread of high-speed Internet services, IEEE 802.3 working group standardized GE-PON (Gigabit Ethernet (registered trademark) -PON) as IEEE 802.3ah, and more economical and faster FTTH (Fiber To The Home). ) It has been introduced in the Japanese market from the end of 2004 toward the construction of systems.

  Starting with the u-Japan concept in Japan, telecommunications carriers and others have set a target of optical subscription of 30 million people in 2010 and are gradually expanding the installation of optical fibers as a broadband subscriber system. A PON system in which one optical fiber is shared by a plurality of users is laid as a main infrastructure of an optical fiber network from the viewpoint of cost.

  Optical fiber laying, etc., is a large-scale project including civil engineering work. Utilizing existing infrastructure, high-speed transmission accompanying technological advances, upgrade of functions and performance for bandwidth expansion, addition of new equipment, etc. There is a need for a technique that enables flexible migration for migration. The present invention relates to a PON system that realizes various migrations.

  An optical subscriber access system includes a point-to-multipoint (point) between a station-side terminator (OLT: Optical Line Terminal) and a subscriber-side terminator (ONU: Optical Network Unit) in an optical fiber subscriber communication network. A PON system is known as a configuration for connection by -to-multipoint).

  FIG. 13 shows a schematic configuration of a general PON system. The PON system uses an optical coupler 13-3 and an optical fiber cable 13-4 between a plurality of subscriber-side terminators (ONU) 13-1 and one station-side terminator (OLT) 13-2. It is a connected system.

  The PON system is an STM-PON that communicates between a station-side terminator (OLT) and a subscriber-side terminator (ONU) (PON section) in a synchronous transfer mode (STM) method, an asynchronous transfer mode. (ATM: Asynchronous Transfer Mode) ATM-PON and B-PON (Broadband PON), and E-PON, which communicates using the Ethernet (registered trademark) system.

  STM-PON, ATM-PON and B-PON are ITU-T (International Telecommunication Union / Telecommunication Standardization Sector) G. 982, G983 series, etc., and for gigabit transmission, G. Recommended as the 984 series.

  G. In the 984 series, it is possible to transfer a TDM (Time Division Multiplexing) signal and a packet in a modified form of GFP (Generic Framing Procedure) in addition to the ATM cell format so far. In addition, E-PON is directed to Ethernet (registered trademark) packet transmission, and a configuration that performs point-to-multipoint connection at the gigabit transmission speed level is standardized as IEEE 802.3ah.

  In the PON system, a time division multiplexing (TDM) method is adopted for downstream transmission from the station-side terminator (OLT) to the subscriber-side terminator (ONU). The transmission frame is broadcast from the device (OLT), and the transmission frame is captured by the corresponding subscriber-side terminal device (ONU) based on the destination information of the transmission frame.

  On the other hand, a time division multiple access (TDMA) system is adopted for upstream transmission from a subscriber-side terminal unit (ONU) to a station-side terminal unit (OLT). This is to avoid collision of transmission frames in the optical coupler when a plurality of subscriber-side termination units (ONUs) simultaneously transmit transmission frames to the station-side termination unit (OLT).

  In order to realize the TDMA scheme, the station-side terminator (OLT) transmits a control frame used only in the PON section to each subscriber-side terminator (ONU), and each subscriber-side terminator (ONU) The transmission start time and the transmission period specified in the control frame from the station side terminal apparatus (OLT) are read, and the frame is transmitted to the station side terminal apparatus (OLT) only from the transmission start time to the transmission period. It becomes possible. Accordingly, each subscriber-side terminal unit (ONU) stores and waits for the frame received from the subscriber terminal until the transmission start time, and then stores the stored frame from the transmission start time to the transmission period. Send to the device (OLT).

  As a prior art document related to the present invention, a time slot dynamic allocation method in a transmission system in which a subscriber line terminating device performs communication by allocating a time slot to a terminal device by polling is described in Patent Document 1 below. ing. In addition, a plurality of terminal devices are connected by optical transmission paths branched to the network side device, and the polling information is sent from the network side device according to the polling request information from the terminal device, and the terminal device designated by the polling information Patent Document 2 below describes a bandwidth allocation method and bandwidth allocation transmission when a variable length packet is converted into a cell corresponding to a time slot and transmitted in a system for transmitting information converted into cells.

Patent Document 3 listed below includes functions such as initial subscriber-side terminal unit (ONU) registration, additional subscriber-side terminal unit (ONU) registration, ranging, and dynamic bandwidth allocation in the GE-PON giga system. (A) A station-side terminator (OLT) periodically transmits a synchronization signal to each of a plurality of subscriber-side terminators (ONUs) after the initial driving, thereby a plurality of subscriber-side terminators (ONUs). ) Is synchronized with one of the periodic signals transmitted periodically, and (b) a subscriber-side terminal unit (ONU) that is synchronized with one of the synchronization signals (Upward data transmission opportunity assignment) The transmission start time and transmission time length of the initial registration request frame included in the frame are grasped, and data with other subscriber-side terminal units (ONUs) at the transmission time of the initial registration request frame Collision A process of transmitting an initial registration request frame to the station-side terminal device (OLT) after a random delay for transmission, and (c) an initial stage given to the grant frame by the station-side terminal device (OLT) receiving the initial registration request frame Calculating a difference between an expected frame arrival time expected from the transmission start time of the registration request frame and an actual frame arrival time and calculating an RTT (Round Trip Time) using a random delay value; After the calculation, the station-side terminator (OLT) registers the subscriber-side terminator (ONU) requesting the subscriber-side terminator (ONU) registration in the subscriber-side terminator (ONU) list, and the subscriber side After giving a new subscriber-side terminal unit (ONU) ID to each of the terminal units (ONU), a registration response frame including this new subscriber-side terminal unit (ONU) ID and RTT is sent. Have been described for the subscriber side terminating device (ONU) Operation implementing the method of GE-PON system characterized in that it comprises the steps, the transmission to the subscriber side terminating device (ONU) requesting registration.
Japanese Patent No. 3490583 JP 2000-196646 A JP 2003-244178 A

  Currently, with the aim of building an economical PON system, the spread of E-PON based on IEEE 802.3ah is rapidly progressing in Japan. However, the transmission speed in the uplink and downlink directions of E-PON is a Gigabit Ethernet (registered trademark) speed, the transmission path speed is 1.25 Gbps, the information speed is 1 Gbps, and the line code is 8B10B.

  Around 2010, the majority of optical subscribers will receive this service, and it is expected that broadband services will be required from users. At this time, it is required to perform migration while taking advantage of the already installed optical fiber infrastructure. In particular, for migration to a transmission rate such as 10 Gbps, discussions have started in March 2006 in IEEE 802.3 10G PHY for EPON, including the wavelength and method used.

  FIG. 14 shows an example of wavelength arrangement (ITU-T G.983.3) of the current PON system and wavelength arrangement in migration. As shown in (a) of the figure, the wavelength 1260 nm to 1360 nm of the PON upstream signal (Upstream) and the wavelength 1480 nm to 1500 nm of the PON downstream signal (Downstream) are the current common specifications for G-PON and GE-PON. ing. The 1550 nm wavelength band can overlay video distribution with downstream signals.

  On the other hand, as shown in FIG. 5B, the PON upstream signal (Upstream) and the PON downstream signal (Downstream) are transmitted and received in the wavelength band of “Future use”, or as shown in FIG. It is necessary to perform migration such as transmitting and receiving a PON upstream signal (Upstream) and a PON downstream signal (Downstream) in the wavelength band and the 1600 nm wavelength band.

  In addition, it is required to use the same optical fiber splitter as the existing optical fiber splitter and perform migration while coexisting, for example, 1 Gbps-PON and 100 bps-PON. In particular, in current PON systems (GE-PON, G-PON), an optical power branching star coupler is used, and migration to 10 Gbps PON is required in this infrastructure. An object of the present invention is to provide a PON system that can flexibly cope with future PON upgrades in various steps while utilizing an existing optical fiber infrastructure.

  The PON system of the present invention includes (1) an existing subscriber in a PON system comprising a plurality of subscriber-side terminators (ONU) and station-side terminators (OLT) connected by optical fibers via an optical splitter. Includes the receivable wavelength or transmission rate or the transmittable wavelength or transmission rate of the new subscriber-side termination unit (ONU) or upgraded subscriber-side termination unit (ONU) with respect to the side termination unit (ONU) Means for notifying entry information to the station-side terminator (OLT) from the existing subscriber-side terminator (ONU) by a PON control frame when registering the subscriber-side terminator (ONU) in the PON system; In the station-side terminating device (OLT), based on the entry information notified from the subscriber-side terminating device (ONU), the subscriber-side terminating device (ONU) The configuration of the PON system including the wavelength or transmission speed of the transmission signal or reception signal to be determined is determined, and the configuration information of the PON system including the wavelength or transmission speed of the determined transmission signal or reception signal is transmitted to the subscriber-side termination device ( Means for notifying the ONU).

  (2) A wavelength that can be received by the new subscriber-side termination unit (ONU) or the upgraded subscriber-side termination unit (ONU) is a first that can be received by the existing subscriber-side termination unit (ONU). If the second wavelength is different from the wavelength of, when the information addressed to the subscriber-side termination device (ONU) in the downstream signal from the station-side termination device (OLT) by the second wavelength, It is characterized by comprising means for taking in the information associated with the MAC address assigned to the subscriber-side terminal unit (ONU) or the MAC address assigned to the newly installed receiver and the assert import ID.

  Also, (3) information destined for the subscriber-side termination device (ONU) in a downstream signal from the station-side termination device (OLT) using the second wavelength is converted into the existing subscriber-side termination device (ONU). ) To encrypt with the encryption information transmitted from the station side terminal device (OLT).

  (4) A wavelength that can be transmitted by the new subscriber-side termination unit (ONU) or the upgraded subscriber-side termination unit (ONU) is transmitted by the existing subscriber-side termination unit (ONU). Or a plurality of fourth, fifth,..., Nth (integer) different from the third wavelength that can be transmitted by the existing subscriber-side terminal unit (ONU). ) Is provided with traffic distribution means on the user network interface (UNI) side, and the traffic distribution means transmits the traffic to be transmitted to the station side terminal apparatus (OLT) according to a predetermined rule. Or a plurality of fourth, fifth,... N (integer) wavelength transmitters.

  (5) The traffic distribution means, when a failure occurs in the transmission communication path of any wavelength, transmits the traffic to be transmitted to the station side terminal apparatus (OLT) so that the transmission communication path of the remaining wavelength is used. It is characterized by sorting.

  Further, (6) the station-side terminal device (OLT) has different wavelengths from each subscriber-side terminal device (ONU) according to the uplink traffic transmission permission time slot instructed to each subscriber-side terminal device (ONU). And a means for allocating received signals of different transmission rates to receivers of corresponding wavelengths or transmission rates.

  According to the present invention, the station-side terminal device (OLT) notifies the station-side terminal device (OLT) of entry information such as a wavelength or transmission rate that can be transmitted / received by the newly installed or upgraded subscriber-side terminal device (ONU). By determining the configuration of the PON system based on the entry information, it is possible to flexibly cope with PON upgrades in various steps in the future while utilizing the existing optical fiber infrastructure. It is possible to implement wide area network enhancements and function updates at a low price. Until now, the PON system was constructed with a fixed system configuration. However, according to the present invention, it is possible to upgrade the flexible PON system while effectively utilizing the existing optical fiber infrastructure. Become.

  FIG. 1 shows a basic form of migration of a PON system according to the present invention. As shown in the figure, in a PON system comprising a plurality of subscriber-side terminators (ONU # 1 to #n) and a station-side terminator (OLT) connected by a single optical fiber, for example, a subscriber-side terminator When a new terminal unit (ONU) is newly added to an existing terminal unit (ONU) or an existing terminal unit (ONU) is upgraded in the device (ONU # n), a new terminal unit (ONU) or Entry information such as the receivable wavelength or transmission speed or the transmittable wavelength or transmission speed of the terminating unit (ONU) to be upgraded is entered when the subscriber-side terminating unit (ONU) is powered on. In the PON registration (discovery) of the terminating device (ONU), the existing terminating device (ONU) in the PON control frame (packet) changes to the station-side terminating device (OL). To notify to).

  The station-side terminator (OLT) receives the entry information from each subscriber-side terminator (ONU) and determines the PON system configuration based on the entry information. With this configuration, migration from an existing PON system becomes possible. For the notification of the entry information, in the case of IEEE 802.3ah, unused bytes of the REGISTER REQ MPCPDU (2-1) and REGISTER MPCPDU (2-2) messages transmitted and received at the time of discovery shown in FIG. 2 are defined and used. .

  An example of the definition of this unused byte is shown in FIGS. FIG. 3A shows a REGISTER REQ MPCPDU message transmitted from the subscriber-side terminating device (ONU) to the station-side terminating device (OLT). Using the “Pad / Reserved” of the REGISTER REQ MPCPDU, entry information of a newly installed or upgraded subscriber-side terminal unit (ONU) is defined and notified to the station-side terminal device (OLT).

  FIG. 3B shows a REGISTER MPCPDU message transmitted from the station-side terminal device (OLT) to the subscriber-side terminal device (ONU). Using the “Pad / Reserved” of the REGISTER MPCPDU, information on the optimum PON configuration is transmitted to the subscriber-side terminal unit (ONU). In this case, when the station side terminal unit (OLT) side is not ready for communication, the subscriber side terminal unit (ONU) is notified of the unavailability of the new or upgraded terminal unit (ONU).

  FIG. 4A shows an example of definition of unused bytes in the REGISTER REQ MPCPDU message (ONU → OLT). As shown in the figure, ONU transmission speed upgrade of existing PON system, transmission speed, ONU reception speed upgrade of existing PON system, reception speed, additional PON system ONU presence, additional PON system Defines the ONU MAC address, Asser Import ID (LLID) request (when receiving only), transmission wavelength, transmission wavelength variation range, transmission speed, reception wavelength, reception wavelength variation range, reception speed, FEC applicability, etc. .

  FIG. 4B shows an unused byte and definition example of the REGISTER MPCPDU message (OLT → ONU). As shown in the figure, ONU transmission speed upgrade confirmation response of existing PON system, permitted transmission speed, ONU reception speed upgrade confirmation response of existing PON system, permitted reception speed, ONU confirmation response of additional PON system, additional PON System ONU MAC address confirmation response, Assert Import ID (LLID) (when receiving only), permitted transmission wavelength, permitted transmission wavelength variation range, permitted transmission speed, permitted reception wavelength, permitted reception wavelength variation range, permitted reception Define speed, FEC usage notification, etc.

  FIG. 5A shows an example of migration for improving the speed performance of an existing receiver in a subscriber-side terminal unit (ONU). The example shown in the figure is a standardized system in which the existing PON system is described in IEEE 802.3ah, and the transmission rate in the upstream and downstream directions is 1 Gbps (the optical transmission rate is 8B10B converted to 1.25 Gbps). In addition to the wavelength transmission / reception function of the existing PON system, the receivable wavelength is the same wavelength as the existing standard specification (1490 nm +/− 10 nm). In the case where upgrade to 10 Gbps is possible as a receivable transmission rate, for example, entry information indicating that the receivable rate is 10 Gbps is received from the existing transmitter in the PON control frame (packet) by the station side terminal device (OLT ) Is provided.

  FIG. 5B shows an example of migration in which a receiver is newly installed in addition to the existing transmitter / receiver in the subscriber-side terminal unit (ONU). The example shown in the figure is a standardized system in which the existing PON system is described in IEEE 802.3ah, and the transmission rate in the upstream and downstream directions is 1 Gbps (the optical transmission rate is 8B10B converted to 1.25 Gbps). In addition to the transmission / reception function of the wavelength that can be transmitted / received by the existing PON system, the wavelength that can be received is different from the existing standard specification (1490 nm +/− 10 nm). If it is a wavelength and upgradeable to, for example, 10 Gbps as a receivable transmission rate, the receivable rate is 10 Gbps, and entry information of a wavelength different from the standard specification (1490 nm +/− 10 nm) is used as the reception wavelength. Provided with means for notifying the terminal unit (OLT) by a PON control frame (packet) from the transmitter

  In addition to the existing transmitter / receiver, a receiver is newly installed, and the information that can be received by the new receiver is such that the receivable wavelength of the new receiver is different from the existing standard specification (1490 nm +/− 10 nm). If there is, the information addressed to the subscriber terminal unit (ONU) in the downlink direction by this wavelength includes the MAC address of the subscriber terminal unit (ONU) or the MAC address assigned to the new receiver and the assert import ID. Means for fetching information associated with (LLID). In this case, the MAC address of the new receiver is transmitted to the station-side terminal device (OLT) by an upstream signal from the existing subscriber-side terminal device (ONU).

  Further, as a form of extracting encrypted information with a new receiver, when the receivable wavelength is a wavelength different from the existing standard specification (1490 nm +/− 10 nm), the subscriber-side terminating device in the downlink direction by this wavelength ( The information addressed to the ONU) is encrypted with the encryption information transmitted to the station-side terminator (OLT) by the upstream signal from the existing subscriber-side terminator (ONU) and transmitted to the subscriber-side terminator (ONU). It can be configured.

  FIG. 5C shows an example of migration in which a transmitter / receiver is newly installed in addition to the existing transmitter / receiver in the subscriber-side terminal unit (ONU). In the example shown in the figure, the existing PON system is a standardized method described in IEEE 802.3ah, and the transmission rate in the upstream and downstream directions is 1 Gbps (the optical transmission rate is 8B10B converted to 1.25 Gbps). In addition to the transmission / reception function of the wavelength that can be transmitted / received by the existing PON system, the wavelength that can be received is different from the existing standard specification (1490 nm +/− 10 nm). If the transmission speed that can be received is, for example, 10 Gbps, the wavelength that can be transmitted is different from the existing standard specification (1260 nm to 1360 nm), and the transmission speed that can be transmitted is, for example, 10 Gbps, Entry information including information is passed from the existing transmitter to the station side terminal equipment (OLT) in the PON control frame (packet). Comprising means for.

  FIG. 6A shows an example of migration for improving the speed performance of an existing receiver (no upgrade is required) and an existing transmitter in a subscriber-side terminal unit (ONU). The example shown in the figure is a standardized system in which the existing PON system is described in IEEE 802.3ah, and the transmission rate in the upstream and downstream directions is 1 Gbps (the optical transmission rate is converted to 8B10B and is 1.25 Gbps). In addition to the wavelength transmission / reception function of the existing PON system, the newly installed subscriber-side termination unit (ONU) or the upgraded subscriber-side termination unit (ONU) has a receivable wavelength existing standard. Transmission speed that can be received at the same wavelength as the specification (1490 nm +/− 10 nm), for example, 10 Gbps, and transmission speed that can be transmitted at the same wavelength as the existing standard specification (12600 m−13600 m) Is, for example, 10 Gbps, entry information including such information is sent from the existing transmitter to the PON control frame. Comprising means for notifying to the station side terminating device (OLT) in the packet).

  FIG. 6B shows a form provided with a traffic distribution function to an existing or new transmitter in the subscriber-side terminal unit (ONU). The example shown in the figure is a standardized system in which the existing PON system is described in IEEE 802.3ah, and the transmission rate in the upstream and downstream directions is 1 Gbps (the optical transmission rate is converted to 8B10B and is 1.25 Gbps). In addition to the transmission / reception function of the wavelength that can be transmitted / received by the existing PON system, the newly installed subscriber-side terminal unit (ONU) is different from the existing standard specification (1260 nm-1360 nm) 1 or In the case of a plurality of wavelengths, a traffic distribution function is provided on the user-network interface (UNI) side, and transmission is performed from the subscriber-side terminal unit (ONU) to the station-side terminal device (OLT) according to a predetermined rule. Traffic to be distributed to the transmitters (S1 to S4) of the respective wavelengths.

  The optical transmission signals from the transmitters (S1 to S4) can be assigned to the upstream band for each wavelength (λ4-1, λ4-2, λ4-3, λ4-4). Further, the number and transmission rate of each transmitter (S1 to S4) may be different for each subscriber-side terminal unit (ONU). In the example shown in the figure, four transmitters with a transmission rate of 2.5 Gbps are provided. However, in another subscriber-side terminal unit (ONU), two transmitters with a transmission rate of 1 Gbps or 10 Gbps are provided. A configuration including three transmission rate transmitters may be used.

  FIG. 6C shows a mode in which a bandwidth distribution function to an existing or new transmitter is provided in a subscriber-side terminal unit (ONU). In the form shown in FIG. 6, in the same way as the form shown in FIG. 6B, the newly installed terminal unit (ONU) has a transmittable wavelength in addition to the transmit / receive function of the existing PON system. When the wavelength is different from the existing standard specification (1260 nm to 1360 nm), the user network interface (UNI) side has a traffic distribution function, and as a predetermined rule, when a transmission communication path with one wavelength is interrupted The traffic distribution function is used as the bandwidth distribution function of the communication path so that the transmission communication path by the other wavelength is used, and transmission is performed using the normal communication path without using the communication path in which the failure is detected. A system having a redundant configuration can be configured.

  FIG. 7A shows an example of migration for improving the speed performance of the existing transmitter in the station-side terminal device (OLT). This figure is a standardized system in which the existing PON system is described in IEEE 802.3ah, and is a bidirectional transmission system in which the transmission speed in the upstream and downstream directions is 1 Gbps (the optical transmission speed is converted to 8B10B and is 1.25 Gbps). In addition to the transmission / reception function of the wavelength that can be transmitted / received in the existing PON system, the station-side termination device (OLT) that can correspond to the subscriber-side termination device (ONU) to be newly installed or upgraded has an existing standard that can transmit wavelengths. A configuration example is shown in which the wavelength is the same as the specification (1490 nm +/− 10 nm), and 10 Gbps can be realized (upgradable) as a transmission rate that can be transmitted.

  As shown in the figure, the output from a transmitter with a standard specification (1490 nm +/− 10 nm) with a transmission rate of 10 Gbps and a transmission rate of 1 Gbps with a standard specification with a wavelength (1490 nm +/− 10 nm). The output from the transmitter is transmitted with different time slots by the speed dividing function in the wavelength multiplexer / demultiplexer (WDM).

  FIG. 7B shows an example of migration of speed performance improvement corresponding to the new installation of the transmitter and the ONU upgrade in the station side terminal device (OLT). This figure is a standardized system in which the existing PON system is described in IEEE 802.3ah, and is a bidirectional transmission system in which the transmission speed in the upstream and downstream directions is 1 Gbps (the optical transmission speed is converted to 8B10B and is 1.25 Gbps). In addition to the transmission / reception function of the wavelength that can be transmitted / received in the existing PON system, the station-side termination device (OLT) that can correspond to the subscriber-side termination device (ONU) to be newly installed or upgraded has an existing standard that can transmit wavelengths. This shows a configuration that is different from the specification (1490 nm +/− 10 nm) and can realize (upgradable), for example, 10 Gbps as a transmission rate that can be transmitted.

  As shown in the figure, the output of the wavelength multiplexer / demultiplexer (WDM) of the existing PON system (the wavelength of the transmission signal is 1490 nm +/− 10 nm of the standard specification) and the wavelength different from the existing standard specification (1490 nm +/− 10 nm) Then, the output of the wavelength multiplexer / demultiplexer (WDM) of a transmission signal having a transmission rate of 10 Gbps, for example, is combined by an optical coupler and transmitted.

  FIG. 7C shows an example of migration for improving the speed performance of the existing receiver in the station-side terminal device (OLT). This figure is a standardized system in which the existing PON system is described in IEEE 802.3ah, and is a bidirectional transmission system in which the transmission speed in the upstream and downstream directions is 1 Gbps (the optical transmission speed is converted to 8B10B and is 1.25 Gbps). In addition to the transmission / reception function of the wavelength that can be transmitted / received by the existing PON system, the station-side termination device (OLT) that can correspond to the subscriber-side termination device (ONU) to be newly installed or upgraded has an existing standard that has a receivable wavelength. The configuration shows the same wavelength as the specification (1260 nm-1360 nm) and the receivable upgrade transmission rate is 10 Gbps, for example.

  FIG. 8A shows an example of migration for improving the speed performance of the receiver in addition to the existing receiver in the station-side terminal device (OLT). The existing PON system is a standardized system described in IEEE 802.3ah, and is a bidirectional transmission system with an uplink / downlink transmission rate of 1 Gbps (the optical transmission rate is 8B10B converted to 1.25 Gbps). Or, the station-side terminator (OLT) that can support the subscriber-side terminator (ONU) to be upgraded has a receivable wavelength in addition to the transmission / reception function of the wavelength that can be transmitted / received by the existing PON system. 1360 nm), and an upgrade receiver capable of realizing reception at an upgrade transmission rate of 10 Gbps, for example, and a function for distributing the upgrade receiver to an existing receiver. The distribution function associates a 1 Gbps signal and a 10 Gbps signal output from a wavelength multiplexer / demultiplexer (WDM) with different time slots into an existing receiver and an upgrade receiver. Distribute.

  The function corresponding to the different transmission rates in the station-side terminal device (OLT) is based on the uplink traffic transmission permission time slot indicated by the station-side terminal device (OLT) to the subscriber-side terminal device (ONU). Since the terminal unit (ONU) transmits each traffic transmission permission time slot at a predetermined transmission rate, the receiver may be assigned to each traffic transmission permission time slot.

  Since the station-side terminator (OLT) controls the bandwidth of the upstream signal from the subscriber-side terminator (ONU), which subscriber-side terminator (ONU) is at what time and how long Since it recognizes whether or not it emits light (signal transmission), it can cope with the above configuration. The upstream traffic transmission permission time slot is instructed by a gate packet from the station side terminal device (OLT). FIG. 9 shows a configuration example (IEEE802.3ah) of the gate packet. As shown in the figure, “Grant # 1 Start time” designates the light emission start time of the subscriber-side terminating device (ONU # 1), and “Grant # 1 Length” designates the subscriber-side terminating device (ONU # 1). Specify the flash duration.

  FIG. 8 (b) shows a newly installed migration form of the transceiver in the station side terminal equipment (OLT). This figure is a standardized system in which the existing PON system is described in IEEE 802.3ah, and is a bidirectional transmission system in which the transmission speed in the upstream and downstream directions is 1 Gbps (the optical transmission speed is converted to 8B10B and is 1.25 Gbps). In addition to the transmission / reception function of the wavelength that can be transmitted / received by the existing PON system, the station-side termination device (OLT) that can correspond to the subscriber-side termination device (ONU) to be newly installed or upgraded has an existing standard that has a receivable wavelength. A configuration example in the case where the wavelength is different from the specification (1260 nm-1360 nm) and the receivable upgrade speed is, for example, 10 Gbps.

  As shown in the figure, the wavelength multiplexer / demultiplexer (WDM1) of the existing PON system and the receivable upgrade speed is 10 Gbps, for example, at a wavelength different from the existing standard specification (1260 nm-1360 nm). A wavelength multiplexer / demultiplexer (WDM 2) to which a new transmitter and receiver are connected is coupled by an optical coupler.

  FIG. 10 shows an integrated schematic diagram of various migrations according to the present invention. In the figure, reference numeral 10-11 denotes a basic configuration of an existing subscriber-side terminating device (ONU), a transmitter and a receiver having an existing basic configuration of the station-side terminating device (OLT), and a downstream signal of wavelength λ1. And an upstream signal of wavelength λ2. 10-12 shows a subscriber-side terminator (ONU) in which an upgraded receiver for receiving a downstream signal of wavelength λ3 is newly added to the basic configuration of the existing subscriber-side terminator (ONU). The function of the newly installed receiver is notified from the existing transmitter to the station-side terminal device (OLT) as entry information.

  10-13 is a subscription in which an upgraded receiver that receives a downstream signal of wavelength λ3 and an upgraded transmitter that transmits an upstream signal of wavelength λ4 is newly installed in the basic configuration of an existing subscriber-side terminal unit (ONU). The person side termination device (ONU) is shown. The functions of the newly installed receiver and transmitter are notified as entry information from the existing transmitter to the station-side terminal device (OLT).

  Reference numeral 10-14 designates a subscriber-side terminator in which an upgraded receiver for receiving a downstream signal of wavelength λ3 is newly installed in the receiver of the existing subscriber-side terminator (ONU), and the existing transmitter is upgraded ( ONU). The upgraded transmitter has a function of transmitting an existing transmission signal of wavelength λ2 at a transmission rate of 1 Gbps and a function of transmitting at an upgraded transmission rate of 10 Gbps.

  10-15 shows the migration which upgraded the existing receiver and existing transmitter in a subscriber side terminal unit (ONU). The upgraded receiver has a function of receiving a signal with a transmission rate of 1 Gbps of the existing wavelength λ1 and a function of receiving a signal with a transmission rate of 10 Gbps that has been upgraded. The upgraded transmitter has a function of transmitting an existing signal with a transmission rate of 1 Gbps of wavelength λ2 and a function of transmitting an upgraded signal with a transmission rate of 10 Gbps.

  The station-side terminator (OLT) 10-2 includes a transmitter 10-21 that transmits a transmission signal having a wavelength λ1 of an existing basic configuration at a transmission rate of 1 Gbps, and a transmission rate of 1 Gbps having a wavelength λ2 of an existing basic configuration. A receiver 10-22 for receiving a signal, and a receiver 10-23 upgraded to receive a signal with a transmission rate of 10 Gbps of wavelength λ2, and a transmission signal of wavelength λ3 at a transmission rate of 10 Gbps A new transmitter 10-24 and a new receiver 10-25 that receives a signal with a transmission rate of 10 Gbps having a wavelength λ4 are added.

  FIG. 11 shows an integrated configuration of a station-side terminator (OLT) according to the present invention. This figure shows a configuration for realizing various migrations in an integrated manner, and it is not always necessary to include all the components, and a configuration including components necessary for each individual migration can be adopted. As shown in the figure, the station-side terminator (OLT) according to the present invention transmits / receives a signal having a wavelength λ1 having an existing basic configuration at a transmission rate of 1 Gbps and receiving a signal having a transmission rate of 1 Gbps having a wavelength λ2. A transmitter 11-2 that transmits a transmission signal of wavelength λ1 at a transmission rate of 10 Gbps, and a receiver 11-3 that receives a signal of transmission rate of 10 Gbps of wavelength λ2.

  A transmission signal with a transmission rate of 1 Gbps with wavelength λ1 and a transmission signal with a transmission rate of 10 Gbps with wavelength λ1 are transmitted in different time slots by the speed distribution function in wavelength multiplexer / demultiplexer (WDM) 11-4. The received signal with the transmission rate of 1 Gbps with the wavelength λ2 and the received signal with the transmission rate of 10 Gbps with the wavelength λ2 are received in different time slots, and are distributed by the speed distribution function in the wavelength multiplexer / demultiplexer (WDM) 11-4. It is done.

  Further, the station-side terminal device (OLT) transmits a transmission signal having a wavelength λ3 different from that of the existing PON system at a transmission rate of 10 Gbps and receives a signal having a transmission rate of 10 Gbps having a wavelength λ4. Is provided. A wavelength multiplexer / demultiplexer (WDM) 11-6 for multiplexing / demultiplexing optical signals of wavelengths λ3 and λ4 transmitted / received by the new transmitter / receiver 11-5, and an optical signal of existing wavelengths λ1 and λ2 The demultiplexing wavelength multiplexer / demultiplexer (WDM) 11-4 is coupled by an optical coupler 11-7. The signals transmitted and received by the existing and new transmitters / receivers are distributed by the distribution device 11-8.

  FIG. 12 shows a schematic diagram of migration of a subscriber-side terminal unit (ONU) having transmitters of a plurality of wavelengths. In the figure, reference numeral 12-11 denotes a basic configuration of an existing subscriber-side terminating device (ONU), and a transmitter 12-21 and a receiver 12 having an existing basic configuration of the station-side terminating device (OLT) 12-2. −22, and a downstream signal of wavelength λ1 and an upstream signal of wavelength λ2.

  12-12 includes an upgraded receiver for receiving a downstream signal of wavelength λ3 and a transmitter for two wavelengths of wavelengths λ4-1 and λ4-2 in the basic configuration of an existing subscriber-side terminal unit (ONU). A newly installed subscriber-side terminal unit (ONU) is shown. The functions of the newly installed receiver and transmitter are notified as entry information from the existing transmitter to the station-side terminal device (OLT).

  Reference numeral 12-13 designates an upgraded receiver for receiving a downstream signal of wavelength λ3, a wavelength λ4-1, λ4-2, λ4-3, and λ4-4 in addition to a basic configuration of an existing subscriber-side terminal unit (ONU). 4 shows a subscriber-side terminal unit (ONU) in which transmitters of four wavelengths are newly installed. The functions of the newly installed receiver and transmitter are notified as entry information from the existing transmitter to the station-side terminal device (OLT).

  12-14 is an upgraded receiver that receives a downstream signal of wavelength λ3 and three wavelengths of wavelengths λ4-1, λ4-2, and λ4-3 in the basic configuration of an existing subscriber-side terminal unit (ONU) 1 shows a subscriber-side terminal unit (ONU) in which a transmitter is newly installed. The functions of the newly installed receiver and transmitter are notified as entry information from the existing transmitter to the station-side terminal device (OLT).

  The station-side terminator (OLT) 12-2 includes a transmitter 12-21 and a receiver 12-22 having an existing basic configuration, a transmitter 12-23 having a wavelength λ3, wavelengths λ4-1, λ4-2, and λ4. Add receivers 12-24, 12-25, 12-26, 12-27 for four wavelengths -3 and λ4-4.

  Note that the existing PON system and the PON system to be newly installed or upgraded as described above are not limited to the standardized system described in IEEE 802.3ah, and are not limited to ITU-T GG. The G-PON system recommended in the 984 series may be used, the transmission speed in the uplink and downlink directions may be asymmetric communication, or a system in which they are mixed.

It is a figure which shows the basic form of the migration of the PON system by this invention. It is a figure which shows REGISTER REQ MPCPDU and REGISTER MPCPDU transmitted / received at the time of discovery. It is a figure which shows the message of REGISTER REQ MPCPDU and REGISTER MPCPDU. It is a figure which shows the example of a definition of the unused byte of REGISTER REQ MPCPDU and REGISTER MPCPDU. It is a figure which shows the example of the migration in a subscriber side termination | terminus apparatus (ONU). It is a figure which shows the example of the migration in a subscriber side termination | terminus apparatus (ONU). It is a figure which shows the example of the migration in a station side termination | terminus apparatus (OLT). It is a figure which shows the example of the migration in a station side termination | terminus apparatus (OLT). It is a figure which shows the structural example (IEEE802.3ah) of a gate packet. FIG. 3 is an integrated schematic diagram of various migrations according to the present invention. It is a figure which shows the integrated structure of the station side termination | terminus apparatus (OLT) by this invention. FIG. 2 is a schematic diagram of migration of a subscriber-side termination unit (ONU) having transmitters of multiple wavelengths according to the present invention. It is a figure which shows the schematic structure of a general PON system. It is a figure which shows the example of the wavelength arrangement | positioning in the wavelength arrangement | positioning and migration of the present PON system.

Explanation of symbols

ONU Subscriber-side terminator OLT Station-side terminator 10-11 Basic configuration of existing subscriber-side terminator 10-12 Subscriber-side terminator 10-13 with upgraded receiver 10-13 Upgraded receiver and transmitter Newly installed subscriber-side terminator 10-14 Newly installed receiver, upgraded subscriber-side terminator 10-15 Subscriber-side terminator 10-15 Subscriber-side terminator 10-2 upgraded existing receiver and transmitter 10-2 Station-side terminator 10-21 Existing basic configuration transmitter 10-22 Existing basic configuration receiver 10-23 Upgraded receiver 10-24 New transmitter 10-25 New receiver 11-1 Existing basic Configuration transceiver 11-2 Upgraded transmission rate transmitter 11-3 Upgraded transmission rate receiver 11-4 Wavelength splitting 11-5 New transmitter / receiver 11-6 Wavelength multiplexer / demultiplexer 11-7 Optical coupler 11-8 Distribution device 12-11 Basic configuration of existing subscriber-side terminal device 12-12 Receiver of wavelength λ3 and wavelength λ4 Subscriber-side terminator with newly installed transmitters with -1, λ4-2 12-13 Subscriber with newly installed transmitters with wavelength λ4-1, λ4-2, λ4-3, and λ4-4 Subscriber-side terminator 12-14 Subscriber-side terminator 12-2 station-side terminator (OLT) with newly installed receiver with wavelength λ3 and transmitters with wavelengths λ4-1, λ4-2, and λ4-3
12-21 Transmitter with Existing Basic Configuration 12-22 Receiver with Existing Basic Configuration 12-23 Additional Transmitter with Wavelength λ3 12-24 Additional Receiver with Wavelength λ4-1 12-25 Additional Reception with Wavelength λ4-2 12-26 Additional receiver with wavelength λ4-3 12-27 Additional receiver with wavelength λ4-4

Claims (6)

In a PON (Passive Optical Network) system composed of a plurality of subscriber-side terminators (ONU) and station-side terminators (OLT) connected by optical fibers via an optical splitter,
Receivable wavelength or transmission rate or transmittable wavelength of a new subscriber-side terminal unit (ONU) or an upgraded subscriber-side terminal unit (ONU) with respect to an existing subscriber-side terminal unit (ONU) Entry information including the transmission rate is notified from the existing subscriber-side terminal device (ONU) to the station-side terminal device (OLT) by the PON control frame when the subscriber-side terminal device (ONU) is registered in the PON system. Means to
In the station-side terminator (OLT), based on the entry information notified from the subscriber-side terminator (ONU), the wavelength or transmission rate of the transmission signal or the received signal for the subscriber-side terminator (ONU) is included. Means for determining the configuration of the PON system and notifying the subscriber-side terminal unit (ONU) of the configuration information of the PON system including the wavelength or transmission speed of the determined transmission signal or reception signal;
PON system characterized by comprising.   The wavelength that can be received by the new subscriber-side termination unit (ONU) or the upgraded subscriber-side termination unit (ONU) is different from the first wavelength that can be received by the existing subscriber-side termination unit (ONU). In the case of the second wavelength, when information destined for the subscriber-side termination device (ONU) is extracted from the downstream signal from the station-side termination device (OLT) using the second wavelength, the subscriber-side termination 2. The PON system according to claim 1, further comprising means for fetching information associated with a MAC address assigned to a MAC address of a device (ONU) or a newly installed receiver and an Assert Import ID.   The information addressed to the subscriber-side termination device (ONU) in the downstream signal from the station-side termination device (OLT) by the second wavelength is changed from the existing subscriber-side termination device (ONU) to the station-side termination. The PON system according to claim 2, further comprising means for encrypting with the encryption information transmitted to the device (OLT). The wavelength that can be transmitted by the new subscriber-side termination unit (ONU) or the upgraded subscriber-side termination unit (ONU) is different from the third wavelength that can be transmitted by the existing subscriber-side termination unit (ONU). In the case of the fourth wavelength, or a plurality of fourth, fifth,... N (integer) wavelengths different from the third wavelength that can be transmitted by the existing subscriber-side terminal unit (ONU). If
Traffic distribution means is provided on the user network interface (UNI) side, and the traffic distribution means transmits the traffic to be transmitted to the station-side terminal device (OLT) according to a predetermined rule in the third or fourth wavelength or the plurality of fourth wavelengths. The PON system according to claim 1, wherein the PON system is assigned to transmitters of Nth (integer) wavelengths.   The traffic distribution means distributes traffic to be transmitted to a station side terminal device (OLT) so that a transmission communication path with the remaining wavelengths is used when a failure occurs in the transmission communication path with any wavelength. The PON system according to claim 4.   The station-side terminal device (OLT) receives received signals of different wavelengths from each subscriber-side terminal device (ONU) according to the uplink traffic transmission permission time slot instructed to each subscriber-side terminal device (ONU). The PON system according to claim 1, further comprising means for distributing received signals having different transmission rates to receivers having corresponding wavelengths or transmission rates.

Images