WO2015077943A1 - 无源光网络上行带宽分配的方法、装置及系统 - Google Patents

无源光网络上行带宽分配的方法、装置及系统 Download PDF

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Publication number
WO2015077943A1
WO2015077943A1 PCT/CN2013/087965 CN2013087965W WO2015077943A1 WO 2015077943 A1 WO2015077943 A1 WO 2015077943A1 CN 2013087965 W CN2013087965 W CN 2013087965W WO 2015077943 A1 WO2015077943 A1 WO 2015077943A1
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Prior art keywords
onu
bwmap
bandwidth
olt
response time
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PCT/CN2013/087965
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English (en)
French (fr)
Inventor
赵望生
梁选勤
万席锋
郑刚
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华为技术有限公司
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Priority to PCT/CN2013/087965 priority Critical patent/WO2015077943A1/zh
Priority to CN201380002382.5A priority patent/CN104919759B/zh
Publication of WO2015077943A1 publication Critical patent/WO2015077943A1/zh

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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04QSELECTING
    • H04Q11/00Selecting arrangements for multiplex systems
    • H04Q11/0001Selecting arrangements for multiplex systems using optical switching
    • H04Q11/0062Network aspects
    • H04Q11/0067Provisions for optical access or distribution networks, e.g. Gigabit Ethernet Passive Optical Network (GE-PON), ATM-based Passive Optical Network (A-PON), PON-Ring
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04QSELECTING
    • H04Q11/00Selecting arrangements for multiplex systems
    • H04Q11/0001Selecting arrangements for multiplex systems using optical switching
    • H04Q11/0062Network aspects
    • H04Q2011/0064Arbitration, scheduling or medium access control aspects

Definitions

  • the present invention relates to bandwidth allocation technologies in the field of network communication technologies, and in particular, to a method, device and system for uplink bandwidth allocation in a passive optical network.
  • GPON Point to Mutil-Point
  • P2MP Point to Mutil-Point
  • ONT Optical Line Terminal
  • ODN optical distribution network
  • ONU Optical Network Unit
  • the ODN consists of passive optical components such as single-mode fiber, optical splitter, and optical connector, providing an optical transmission medium for the physical connection between 0LT and 0NU.
  • 0LT In the uplink direction of the GP0N system, multiple 0NUs need to send uplink optical signals, and 0LT specifies a time slot for each ONU to send uplink optical signals by carrying a bandwidth allocation bitmap (BWmap) in the downlink frame. After receiving the BWmap sent by the 0LT, the 0NU parses the BWmap and emits light in the specified time slot. In order to improve the bandwidth utilization, the 0LT needs to dynamically allocate the uplink bandwidth of each 0NU according to the actual traffic, and send a BWmap every frame and send one frame every 125 ⁇ s.
  • BWmap bandwidth allocation bitmap
  • Each 0NU supports multiple transport containers (Transmission Container, TO, the more TCs supported by the ONU, the larger the BWmap allocated by the OLT to the ONU, and the longer the BWmap is resolved.
  • TO Transmission Container
  • the embodiments of the present invention provide a method, a device, and a system for uplink bandwidth allocation of a passive optical network, which significantly shorten the allocation period and reduce the requirement for the 0NU cache.
  • an embodiment of the present invention provides a bandwidth allocation method, where the bandwidth allocation method is applied to a passive optical network system, where the system includes an optical line terminal OLT and at least one optical network unit ONN, any one of The optical network unit OLT supports a plurality of transmission containers TC, the method comprising the ONU receiving a plurality of downlink frames from the OLT, each of the downlink frames carrying a bandwidth allocation bitmap BWmap, wherein the BWmap includes N The N subfields of the TC allocated bandwidth, where N is an integer greater than 512; the ONU parses the BWmap to obtain a bandwidth of the TC allocated to the ONU; and the ONU is based on the obtained bandwidth of the TC Send upstream data.
  • the method further includes: the ONU parsing the BWmap by using an ONU response time, where the ONU response time is greater than 36 us, and the 0NU response time is used for Identifies the ONU circuit delay time.
  • the ONU response time is an ONU response time that is sent by the 0LT to the ONU; or, the ONU response time is configured by the ONU itself. 0NU response time.
  • the 0NU response time is that the 0LT is based on the number of the TCs connected under the port, or the BWmap can carry.
  • the BWmap further comprising the ONU parsing the BWmap according to an equivalent delay time EQD, wherein the EQD is sent to the ONU for the 0LT, and the EQD is used to identify the 0LT port distance and the ONU The distance, the EQD is one or more integer multiples of 125 microseconds.
  • BWmap further comprising: the 0NU parsing the BWmap according to a bandwidth start time StartTime, where the StartTime is sent by the 0LT to the 0NU,
  • the StartTime is used to identify the location of the illuminating time slot allocated to the TC in the BWmap, and the StartTime is one or more integer multiples of 125 microseconds.
  • the embodiment of the present invention further provides a bandwidth allocation method, where the bandwidth allocation method is applied to a passive optical network system P0N, where the system P0N includes an optical line terminal OLT and at least one optical network unit ONU.
  • Any one of the optical network units OLT supports a plurality of transmission containers TC, and receives the uplink data transmitted by the ONU according to the bandwidth of the TC obtained by parsing the BWmap.
  • the method includes the optical line terminal OT transmitting a plurality of downlink frames, each of the downlink frames carrying a bandwidth allocation bitmap BWmap, where the BWmap includes N subfields for allocating bandwidths for the N TCs, where N is greater than An integer of 512.
  • the 0LT sends an ONU response time to the ONU, where the 0NU response time is used by the ONU to parse the BWmap, and the 0NU response time is used to identify The circuit delay time of the ONU.
  • the 0NU response time is The OLT is calculated according to the number of the TCs connected to the port, or the maximum number of the TCs that the BWmap can carry.
  • the method further includes that the 0LT sends an equivalent delay time EQD to the ONU, where the EQD is used by the ONU to parse the BWmap, where The EQD is used to identify the distance between the OLT port and the ONU, and the EQD is one or more integer multiples of 125 microseconds.
  • the method further includes that the 0LT sends a bandwidth start time StartTime to the ONU, where the StartTime is used by the ONU to parse the BWmap, where The StartTime is used to identify the location of the illuminating time slot allocated to the TC in the BWmap, and the StartTime is one or more integer multiples of 125 microseconds.
  • an optical network unit includes a receiving unit, configured to receive multiple downlink frames from the OLT, each of the downlink frames carrying a bandwidth allocation bitmap BWmap, where the BWmap includes allocating bandwidth for the N TCs N subfields, where N is an integer greater than 512; a parsing unit, configured to parse the BWmap to obtain a bandwidth of the TC allocated to the ONU; and a sending unit, configured to use, according to the obtained bandwidth of the TC Send upstream data.
  • the parsing unit is configured to parse the BWmap, obtain a bandwidth of the TC allocated to the ONU, and further include the ONU using a 0NU response time resolution The BWmap, wherein the ONU response time is greater than 36 us, and the ONU response time is used to identify the ONU circuit delay time.
  • the ONU response is an ONU response time that is sent by the OLT to the ONU; or, the ONU response time is an ONU configured by the ONU itself. Response time.
  • the 0NU response time is that the 0LT is calculated according to the number of the TCs connected under the port, or the maximum number of the transport containers that the BWmap can carry. Drawn.
  • the parsing unit is configured to parse the BWmap, obtain a bandwidth of the TC allocated to the ONU, and further include the 0NU according to an equivalent delay time EQD Parsing the BWmap, where the EQD is sent to the ONU, and the EQD is used to identify that the distance between the 0LT port and the ONU is one or more times the EQD is 125 microseconds.
  • An integer multiple is configured to parse the BWmap, obtain a bandwidth of the TC allocated to the ONU, and further include the 0NU according to an equivalent delay time EQD Parsing the BWmap, where the EQD is sent to the ONU, and the EQD is used to identify that the distance between the 0LT port and the ONU is one or more times the EQD is 125 microseconds. An integer multiple.
  • the parsing unit is configured to parse the BWmap, obtain a bandwidth of the TC allocated to the ONU, and further include the 0NU according to a bandwidth start time StartTime Parsing the BWmap, where
  • the StartTime is sent to the 0NU by the 0LT, and the StartTime is used to identify the position of the illuminating time slot allocated to the TC in the BWmap, and the StartTime is one or more integer multiples of 125 microseconds.
  • an optical line terminal where the OLT includes a sending unit, configured to send multiple downlink frames, each of which carries a bandwidth allocation bitmap BWmap, where the BWmap includes allocating bandwidth for the N TCs. N subfields, where N is an integer greater than 512; a receiving unit, configured to receive uplink data sent by the ONU according to the bandwidth of the TC obtained by parsing the BWmap.
  • the sending unit is further configured to send an ONU response time to the ONU, where the 0NU response time is used by the ONU to parse the BWmap, and the ONU response time is used by The circuit delay time for identifying the ONU.
  • the 0NU response time is that the 0LT is calculated according to the number of the TCs connected under the port, or the maximum number of the TCs that the BWmap can carry. Out.
  • the sending unit is further configured to send an equivalent delay time EQD to the ONU, where the EQD is used to parse the BWmap, and the EQD is used to identify The EQD is used to identify the distance between the 0LT port distance and the ONU, and the EQD is one or more integer multiples of 125 microseconds.
  • the sending unit is further configured to send a bandwidth start time StartTime to the ONU, where the StartTime is used by the ONU to parse the BWmap, where the StartTime is used to identify The position of the illuminating time slot assigned to the TC in the BWmap, the StartTime being one or more integer multiples of 125 microseconds.
  • a fifth aspect a passive optical network system, comprising the optical network unit according to any one of the possible implementation manners of the third aspect, and the optical line terminal as described in any one of the possible implementation manners of the fourth aspect .
  • the number of allocated bandwidth per frame of the 0LT can be expanded from 512 to 2047, which significantly shortens the allocation period, reduces the requirement for the ONU cache, and further reduces the service delay such as time division multiplexing carried by the ONU. User satisfaction.
  • FIG. 1 is a schematic diagram of a network architecture based on an embodiment of the present invention
  • FIG. 2 is a schematic structural diagram of a GTC frame according to an embodiment of the present invention.
  • FIG. 3 is a schematic diagram of a BWmap issued by an 0LT according to an embodiment of the present invention.
  • FIG. 4 is a schematic diagram of a 0NU parsing BWmap provided by an embodiment of the present invention.
  • FIG. 5 is a schematic flowchart of a method for uplink bandwidth allocation of a passive optical network according to an embodiment of the present invention
  • FIG. 6 is a schematic diagram of a 0NU registration authentication process provided by an embodiment of the present invention.
  • FIG. 7 is a schematic structural diagram of an optical network unit according to an embodiment of the present invention
  • FIG. 8 is a schematic structural diagram of an optical line terminal according to an embodiment of the present invention.
  • FIG. 1 is a schematic structural diagram of a GP0N optical network based on an embodiment of the present invention.
  • PON Passive Optical Network
  • the OLT provides a network side interface for the PON system, connecting one or more 0DNs.
  • the ODN is a passive optical splitting device that splits the downlink data of the 0LT to each 0NU and simultaneously transmits the uplink data of multiple 0NU/0NTs to the 0LT.
  • the ONU provides a user-side interface for the PON system, and the uplink is connected to the 0DN. If the 0NU directly provides the user port function, such as an Ethernet user port for PC (Personal Computer) access, it is called 0NT, and the 0NU system mentioned below. Refers to 0NU and 0NT.
  • the ONU to OLT uplink transmission adopts a multi-point to point method, and the 0LT to 0NU downlink transmission adopts a point-to-multipoint method.
  • the TCXTransmission Container, transport container) 1, TC2, TC3, etc. shown in FIG. 1 represent transport containers defined by the GP0N system, and each ONU can be assigned one or more TCs to output data, wherein different service types pass different TCs. Transfer to 0LT.
  • the data transmission in the downlink direction (from 0LT to 0NU direction) is broadcast, and each 0NU receives all downlink frames, and then according to the 0NU identifier.
  • Alloc-ID Al location Identifier
  • the transmission medium is transmitted by the ONUs in the time slot allocated by the OLT to the OLT through the uplink bandwidth allocation bitmap (BWmap), where the BWmap is carried in the downlink frame.
  • BWmap uplink bandwidth allocation bitmap
  • the downlink frame may be a GPON Transmission Convergence (GTC) frame.
  • the GTC frame includes a peer domain, a superframe indicator field, a message processing domain, a bit interleaved parity code field, a downlink payload length field, and a bandwidth allocation bitmap and a payload.
  • the embodiments described below may be applied in a GP0N system or in a 10-Gigabit-capable Passive Optical Network (XG-PON) system.
  • the downlink frame described in the following embodiments may be the GTC frame or the XG-PON transmission convergence (XGTC) frame. As shown in FIG.
  • the GTC frame structure is used to identify that the OLT authorizes each service type TC of the ONU through the bandwidth allocation bitmap BWmap in the downlink frame, and the start time field and the end time field are respectively used to identify the ID.
  • the structure of the BWmap is as shown in FIG. 3, and the BWmap has N allocation structures, where N is a natural number.
  • Each allocation structure is identified by a bandwidth allocation (Al loc-ID), a bandwidth start time (Start Time), and a bandwidth (Grant Size), where Al loc-ID is used to identify a transport container (T-C0NT). ID; Broadband start time Start Time is a 16-bit string used to identify the location of the allocated time slot in this frame; Size is used to identify the number of bytes allocated by the bandwidth allocation bitmap BWmap to the transport container.
  • All the 0NUs connected to the 0LT receive the downlink frames carrying the BWmap, and after parsing the BWmaps, respectively, each of them transmits the uplink light in the time slot specified by the BWmap.
  • the time from the receipt of the BWmap to the transmission of the upstream light by the 0NU includes:
  • the 0NU response time (ResponseTime, Rsptime) is used to identify the circuit delay of the ONU receiving the BWmap, which is 35 ⁇ 1 s according to the standard G987. 3;
  • the equivalent delay time (Equalization Delay, EQD) ) , depending on the distance range of the OLT port and the distance of the ONU, may be 0;
  • the bandwidth start time (Start Time) may be 0 depending on the position of the allocated time slot in this frame.
  • the present invention is abbreviated as 0LT for the optical line terminal and 0NU for the optical network unit.
  • the method for allocating the uplink bandwidth of the passive optical network according to the embodiment of the present invention is described in detail below, as shown in FIG. 5.
  • 0LT sends a broadcast message to the 0NU, and the broadcast message carries a BWmap, where each frame BWmap allocates bandwidth for N TCs, N is a natural number greater than 512, and 0NU receives the BWmap broadcast message from 0LT.
  • the maximum value of N is 2047.
  • 0LT periodically sends profile information (Profile Message), and periodically allocates sequence code SN to report bandwidth; Profile message has delimiter, preamble and other information; 0NU receives profile message, and reports sequence code SN Reported to SN;
  • 0LT After receiving the SN reported by 0NU, 0LT finds 0NU and assigns 0NU identifier 0NU-ID; 0NU receives 0NU-ID and enters 04 state;
  • 0LT allocates ranging bandwidth; 0NU responds to ranging message; 0LT delivers equivalent delay time EQD; 0NU enters 05 state, online is completed;
  • the broadcast packet may be sent by using a physical layer organization and management (PL0AM) message, and may also be customized by using a new message.
  • PL0AM physical layer organization and management
  • the embodiment of the present invention is not limited to the specific message message.
  • the broadcast message carries a profile message (Profile Message), where the summary information is specified by the G987. 3 standard, and the 0NU needs to be reported to the parameter information of the 0LT during the registration authentication process, where
  • the summary information carries the 0NU response time (RspTime).
  • the response time can be 0LT.
  • the number of TCs connected to the port, or the maximum number of TCs that can be carried by the BWmap calculate the Response time required to resolve the BWmap.
  • the maximum number of TCs is 2047.
  • the calculation of the calculation here is 0LT based on the actual number of connected TCs.
  • the value range of time is 6 (T70us), and the present invention does not limit the numerical range of the specific 0NU response time.
  • RspTime is the 0NU response time
  • N is the actual number of TCs.
  • the specific Profile message structure can be as shown in Table 1: Table 1 Profile message content
  • the OLT After the 0NU response time (Response time, RspTime) is calculated, the OLT sends the broadcast packet to the 0LT.
  • 0LT delivers a bandwidth of more than 512 TCs to 0NU per frame through BWmap.
  • S502 The ONU parses the BWmap to obtain a bandwidth of the transmission container allocated to the ONU.
  • the time for the 0NU parsing message has three parts: 0NU response time (RSPTime), equivalent delay time (EQD), and bandwidth start time (Start Time).
  • the ONU parses the BWmap according to the received 0NU response time in the broadcast message, instead of the 35 ⁇ 1 s specified by the standard G987. 3; the equivalent delay time and the bandwidth start time are in accordance with the standard G987. The prescribed operation of .
  • the 0NU sends uplink data according to the obtained bandwidth of the TC, where the 0LT receives the uplink data.
  • the number of allocated bandwidth per frame can be expanded from 512 to 2047, which significantly shortens the allocation period, reduces the requirement for the ONU cache, and further reduces the service delay such as time division multiplexing carried by the ONU, thereby improving the service delay. customer satisfaction.
  • Embodiment 2
  • the embodiment of the present invention further provides a method for allocating an uplink bandwidth of a passive optical network.
  • the 0LT sends a broadcast packet to the ONU, where the broadcast packet carries a BWmap, where each frame BWmap allocates bandwidth for N TCs, and N is greater than a natural number of 512;
  • the maximum value of N is 2047.
  • the broadcast packet may be sent through a Physical Layer Organization and Management (PLOAM) message, and a new message may be customized to be sent.
  • PLOAM Physical Layer Organization and Management
  • the embodiment of the present invention is not limited to the specifically used message packet. Text.
  • the 0NU assembles the uplink data according to the total bandwidth of the N transport containers allocated by the BWmap and sends it to the 0LT.
  • the 0NU does not use the 0NU response time specified by the existing standard G987. 3, but uses the actually measured 0NU response time to be able to resolve a BWmap greater than 512 TCs.
  • the actual estimated 0NU response time is 0LT.
  • the maximum number of TCs here is 2047.
  • the calculation of the calculation here is that the 0LT is calculated based on the number of TCs actually connected.
  • the actual value of the 0NU response time is 6 (T70us), and the present invention does not limit the numerical range of the specific 0NU response time.
  • both the equivalent delay time and the bandwidth start time operate in accordance with standard specifications.
  • the number of allocated bandwidth per frame can be expanded from 512 to 2047, which significantly shortens the allocation period and reduces the requirement for the 0NU cache.
  • the embodiment of the present invention further provides a method for allocating an uplink bandwidth of a passive optical network.
  • the 0LT sends a broadcast packet to the ONU, where the broadcast packet carries a BWmap, where each frame BWmap allocates bandwidth for N TCs, and N is greater than 512.
  • Natural number
  • the maximum value of N is 2047.
  • the 0LT sends a broadcast message to the 0NU during the 0NU registration authentication process.
  • the 0NU registration authentication process is as shown in FIG. 6 and includes five processes. For details, please refer to the G987. 3 standard:
  • the ONU is first in the 01 state, which is the ready state;
  • 0LT periodically sends the summary message "Profile Message”, and periodically assigns the sequence code SN to report the bandwidth;
  • “Profile Message” has the delimiter, preamble and other information;
  • 0NU receives the "Profile Message”, after reporting the sequence code Reporting the SN in the period of the SN;
  • 0LT After receiving the SN reported by 0NU, 0LT finds 0NU and assigns 0NU identifier 0NU-ID; 0NU receives 0NU-ID and enters 04 state;
  • 0LT allocates ranging bandwidth; 0NU responds to ranging message; 0LT delivers equivalent delay time EQD; 0NU enters 05 state, online is completed;
  • the broadcast packet may be sent by using a physical layer organization and management (PL0AM) message, and may also be customized by using a new message.
  • PL0AM physical layer organization and management
  • the embodiment of the present invention is not limited to the specific message message.
  • 0LT sends an equivalent delay EQD to 0NU after the above 04 state ranging, where the equivalent delay EQD is fixed by one or more cycles, the one cycle is 125 us, that is, 0LT is sent to 0NU.
  • the equivalent delay time EQD is fixed by an integer multiple of 125us on the existing basis, so that the ONU has enough time to parse the BWmap message.
  • the EQD can be calculated according to the following formula, which can be referred to the standard G987. 3, page 64, as follows:
  • T eqd is used to identify the sum of the equivalent delay time and Round Trip Delay (RTD), calculated according to the farthest ONU, and aligned to an integral multiple of 125us
  • RspTime max is based on the standard G987. 3, RspTime is 35 ⁇ 1 ⁇ s, so RspTime is 36us,
  • L min is used to identify the minimum distance
  • D max is used to identify the distance difference between the minimum distance and the maximum distance.
  • n 1577 , n 127 Used to identify the refractive index of the upstream and downstream, respectively.
  • c is used to identify the speed of light
  • the broadcast packet may be sent by using a physical layer organization and management (PLOAM) message, and may also be customized by using a new message.
  • PLOAM physical layer organization and management
  • the embodiment of the present invention is not limited to the specifically adopted message message.
  • the 0NU assembles the uplink data according to the total bandwidth of the N transport containers allocated by the BWmap and sends it to the 0LT.
  • the 0NU parses the BWmap according to the equivalent delay time carried in the received broadcast message; the 0NU response time is 35 ⁇ 1 ⁇ s specified by the standard G987. 3, and the bandwidth start time is according to the standard G987. The prescribed operation of .
  • the number of allocated bandwidth per frame can be expanded from 512 to 2047, which significantly shortens the allocation period, reduces the requirement for the ONU cache, and further reduces the service delay such as time division multiplexing carried by the ONU, thereby improving the service delay. customer satisfaction.
  • Embodiment 4 The embodiment of the present invention further provides a method for allocating an uplink bandwidth of a passive optical network.
  • the 0LT sends a broadcast packet to the ONU, where the broadcast packet carries a BWmap, where each frame BWmap allocates bandwidth for N TCs, and N is greater than 512.
  • Natural number
  • the maximum value of N is 2047.
  • the broadcast packet may be sent by using a physical layer organization and management (PLOAM) message, and may also be customized by using a new message.
  • PLOAM physical layer organization and management
  • the embodiment of the present invention is not limited to the specific message message.
  • the bandwidth start time StartTime of the BWmap of each frame is fixedly increased by one or more cycles, the one cycle is 125us, and the g ⁇ 0LT is sent to the broadcast of the ONU.
  • the StartTime carried in the BWmap is fixed by an integer multiple of 125us on the existing basis, so that the ONU has enough time to parse the BWmap message.
  • the 0NU parses the BWmap according to the bandwidth start time carried in the received broadcast message, and sends the uplink light.
  • the number of allocated bandwidth per frame can be expanded from 512 to 2047, which significantly shortens the allocation period and reduces the requirement for the 0NU cache.
  • the fifth embodiment of the present invention provides an optical network unit ONU. As shown in FIG. 7, the method includes: a receiving unit 710, configured to receive multiple downlink frames from the OLT, and each of the downlink frames carries a bandwidth allocation bitmap.
  • the BWmap includes N subfields for allocating bandwidth for the N TCs, where N is an integer greater than 512;
  • the parsing unit 720 is configured to parse the BWmap to obtain a bandwidth of the TC allocated to the ONU, and the sending unit 730 is configured to send uplink data according to the obtained bandwidth of the TC.
  • the ONU parses the BWmap by using a 0NU response time, where
  • the 0NU response time is greater than 36 us, and the 0NU response time is used to identify the 0NU circuit delay time.
  • the ONU parses the BWmap according to an equivalent delay time EQD, where the EQD is sent to the ONU, and the EQD is used to identify the distance between the 0LT port distance and the ONU.
  • the EQD is one or more integer multiples of 125 microseconds.
  • the 0NU parses the BWmap according to the bandwidth start time StartTime, where the StartTime is sent by the 0LT to the 0NU,
  • the StartTime is used to identify the position of the illuminating time slot allocated to the TC in the BWmap, the StartTime being one or more integer multiples of 125 microseconds.
  • the 0NU response is the 0NU response time sent by the 0LT to the 0NU; or, the 0NU response time is the 0NU response time configured by the 0NU itself.
  • the 0NU response time is calculated by the 0LT according to the number of the TCs connected under the port, or the maximum number of the transport containers that the BWmap can carry.
  • the maximum number of the transport containers that the BWmap can carry is 2047.
  • Embodiment 6 An embodiment of the present invention provides an optical line terminal OLT. As shown in FIG. 8, the method includes: a sending unit 810, configured to send multiple downlink frames, where each downlink frame carries a bandwidth allocation bitmap BWmap, where the BWmap is included N TCs allocate N subfields of bandwidth, where N is an integer greater than 512;
  • the receiving unit 820 is configured to receive uplink data that is sent by the 0NU according to the bandwidth of the TC obtained by parsing the BWmap.
  • the 0LT sends a 0NU response time to the 0NU, where the 0NU response time is used by the 0NU to parse the BWmap, and the ONU response time is used to identify the circuit delay time of the ON U.
  • the sending unit is further configured to send an equivalent delay time EQD to the ONU, where the EQD is used to parse the BWmap, and the EQD is used to identify the EQD to identify the 0LT port.
  • the distance from the ONU, the EQD is one or more integer multiples of 125 microseconds.
  • the sending unit is further configured to send a bandwidth start time StartTime to the 0NU, where the StartTime is used by the 0NU to parse the BWmap,
  • the StartTime is used to identify the location of the illuminating time slot allocated to the TC in the BWmap, and the StartTime is one or more integer multiples of 125 microseconds.
  • the 0NU response time is calculated by the 0LT according to the number of the TCs connected under the port, or the maximum number of the TCs that the BWmap can carry.
  • the maximum number of the transport containers that the BWmap can carry is 2047.
  • a system for bandwidth allocation in a passive optical network comprising an optical line terminal and an optical network unit, wherein the optical line terminal is configured to allocate a bitmap through the uplink bandwidth to the optical network unit Allocating bandwidth, wherein the bandwidth allocation bitmap for each frame allocates bandwidth for N transmission containers, and the N is a natural number greater than 512;
  • the optical network unit is configured to assemble uplink data according to a total bandwidth of the N transmission containers allocated by the optical line terminal, and send the uplink data to the optical line terminal.
  • the optical line terminal is further configured to send a broadcast packet to the optical network unit, where the broadcast packet carries a first parsing time, where the first parsing time is used to identify that the optical network unit parses the N The time required for the transport container; the first parsing time is calculated by the optical line terminal according to the number of the transport containers connected, or the maximum number of transport containers that can be carried by the bandwidth allocation bitmap per frame. Out.
  • optical network unit refers to the description of the optical network unit in Embodiment 5.
  • optical line terminal refers to the description of the optical line terminal in Embodiment 6.
  • the interaction process between the optical line terminal and the optical network unit in the bandwidth allocation system in the passive optical network refer to the detailed description of the four uplink bandwidth allocation methods in Embodiments 1 to 4, where I won't go into details.
  • the number of allocated bandwidth per frame of the 0LT can be expanded from 512 to 2047, which significantly shortens the allocation period, reduces the requirement for the ONU cache, and further reduces the service delay such as time division multiplexing carried by the ONU. User satisfaction.
  • the present invention can be implemented by means of software plus a necessary hardware platform, and of course, can also be implemented entirely by hardware.
  • all or part of the technical solution of the present invention contributing to the background art may be in the form of a software product.
  • the computer software product can be stored in a storage medium, such as a ROM/RAM, a magnetic disk, an optical disk, etc., and includes a plurality of instructions for causing a computer device (which may be a personal computer, a server, a network device, etc.) to execute the program.
  • a computer device which may be a personal computer, a server, a network device, etc.

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Abstract

本发明实施例公开一种无源光网络中带宽分配方法,其特征在于,所述方法包括所述ONU接收来自所述OLT的多个下行帧,每个所述下行帧携带带宽分配位图BWmap,所述BWmap包括为N个所述TC分配带宽的N个子字段,其中,N为大于512的整数;所述ONU解析所述BWmap,获得分配给所述ONU的所述TC的带宽;所述ONU根据获得的所述TC的带宽发送上行数据。通过以上技术方案,每帧分配带宽的个数可以从512扩大到2047,显著缩短了分配周期,降低对ONU缓存的要求。

Description

无源光网络上行带宽分配的方法、 装置及系统
技术领域
本发明涉及网络通讯技术领域的带宽分配技术,尤其涉及一种无 源光网络中上行带宽分配的方法、 装置及系统。
背景技术
吉比特无源光网络 (Gigabit Passive Optical Network, GPON) 是一点到多点 (Point to Mutil-Point, P2MP) 的系统, 一个光线路 终端 (Optical Line Terminal , OLT)端口通过光分配网络 (Optical Distribution Network, ODN) 可以连接多台光网络单元 (Optical Network Unit , ONU) 设备。 ODN 由单模光纤、 光分路器、 光连接器 等无源光器件组成, 为 0LT和 0NU之间的物理连接提供光传输媒质。
在 GP0N系统中的上行方向, 多个 0NU需要发送上行光信号, 0LT 通过在下行帧中携带带宽分配位图 (BandWidth map, BWmap) 来指定 每个 ONU发送上行光信号的时隙。 0NU收到 0LT下发的 BWmap后, 解 析 BWmap, 在指定的时隙发光。 为提高带宽利用率, 0LT需要根据实 际流量动态分配每个 0NU的上行带宽,每帧下发 BWmap,且每隔 125 μ s 下发一帧。
由于一台 0NU可以承载多种时分复用业务,且该时分复用业务要 求端到端的时延小于 1. 5ms。 每个 0NU 支持多个传输容器 (Transmission Container, TO, 所述 ONU支持的 TC越多, 则 OLT 给该 ONU分配的 BWmap越大, 解析 BWmap的时间越长。
现有技术中, 当 0LT端口下 TC个数超过 512个, 需要多帧完成 一轮带宽分配。 由于此时 OLT需要下发多帧完成一轮带宽分配, 导致 0NU所承载的时分复用业务时延增加, 超出 1. 5ms的时延要求。
发明内容
有鉴于此,本发明实施例提供一种无源光网络上行带宽分配的方 法、 装置及系统, 显著缩短了分配周期, 降低对 0NU缓存的要求。
第一方面, 本发明实施例提供一种带宽分配方法, 所述带宽分 配的方法应用于无源光网络系统中, 所述系统包括光线路终端 0LT 和至少一个光网络单元 0NU , 所述任意一个光网络单元 0LT支持多 个传输容器 TC, 所述方法包括所述 ONU接收来自所述 OLT的多个下 行帧, 每个所述下行帧携带带宽分配位图 BWmap , 所述 BWmap包括 为 N个所述 TC分配带宽的 N个子字段, 其中, N为大于 512的整数; 所述 0NU解析所述 BWmap , 获得分配给所述 ONU的所述 TC的带宽; 所 述 0NU根据获得的所述 TC的带宽发送上行数据。
在第一方面的第一种可能的实现方式中,所述方法进一歩包括所 述 0NU采用 0NU响应时间解析所述 BWmap , 其中, 所述 0NU响应时 间大于 36 us,所述 0NU响应时间用于标识所述 0NU电路延迟时间。
在第一方面的第二种可能的实现方式中,所述 0NU响应时间是由 所述 0LT下发给所述 0NU的 0NU响应时间; 或者, 所述 0NU响应时间 是所述 0NU自身配置的的 0NU响应时间。
在第一方面的第三种可能的实现方式中, 所述 0NU响应时间是 所述 0LT根据端口下连接的所述 TC的个数, 或所述 BWmap能携带 在第一方面的第四种可能的实现方式中, 所述 0NU解析所述
BWmap , 进一歩包括所述 0NU根据等效延迟时间 EQD解析所述 BWmap , 其中, 所述 EQD为所述 0LT下发给所述 0NU, 所述 EQD用于标识所述 0LT端口距离和所述 0NU的距离, 所述 EQD为 125微秒的一倍或多个 整数倍。
在第一方面的第五种可能的实现方式中, 所述 0NU解析所述
BWmap , 进一歩包括所述 0NU根据带宽起始时间 StartTime解析所述 BWmap , 其中, 所述 StartTime为所述 0LT下发给所述 0NU , 所述
StartTime用于标识分配给所述 TC的发光时隙在所述 BWmap中的位 置, 所述 StartTime为 125微秒的一倍或多个整数倍。
第二方面, 本发明实施例还提供一种带宽分配方法, 所述带宽 分配的方法应用于无源光网络系统 P0N中, 所述系统 P0N包括光线 路终端 0LT和至少一个光网络单元 0NU , 所述任意一个光网络单元 0LT支持多个传输容器 TC, 接收所述 0NU根据解析所述 BWmap获得的 所述 TC的带宽发送的上行数据。 所述方法包括所述光线路终端 0TL 发送多个下行帧, 每个下行帧中携带带宽分配位图 BWmap , 所述 BWmap包括为 N个所述 TC分配带宽的 N个子字段, 其中, N为大于 512 的整数。
在第二方面的第一种可能的实现方式中, 所述 0LT下发 0NU响应 时间至所述 0NU , 其中, 所述 0NU响应时间用于 0NU解析所述 BWmap , 所述 0NU响应时间用于标识所述 0NU的电路延迟时间。
在第二方面的第二种可能的实现方式中, 所述 0NU响应时间是 所述 OLT根据端口下连接的所述 TC的个数, 或所述 BWmap能携带 的最大所述 TC个数计算得出的。
在第二方面的第三种可能的实现方式中, 所述方法还包括所述 0LT下发等效延迟时间 EQD至所述 0NU, 其中, 所述 EQD用于所述 0NU 解析所述 BWmap , 所述 EQD用于标识所述 OLT端口距离和所述 ONU的 距离, 所述 EQD为 125微秒的一倍或多个整数倍。
在第二方面的第四种可能的实现方式中, 所述方法还包括所述 0LT 下发带宽起始时间 StartTime 至所述 0NU , 其中, 所述 StartTime用于所述 0NU解析所述 BWmap , 所述 StartTime用于标 识分配给所述 TC 的发光时隙在所述 BWmap 中的位置, 所述 StartTime为 125微秒的一倍或多个整数倍。
第三方面, 一种光网络单元, 包括接收单元, 用于接收来自 0LT 的多个下行帧, 每个所述下行帧携带带宽分配位图 BWmap , 所述 BWmap包括为 N个所述 TC分配带宽的 N个子字段, 其中, N为大于 512 的整数; 解析单元, 用于解析所述 BWmap , 获得分配给所述 ONU的所 述 TC的带宽; 发送单元, 用于根据获得的所述 TC的带宽发送上行数 据。
在第三方面的第一种可能的实现方式中,所述解析单元用于解析 所述 BWmap , 获得分配给所述 ONU的所述 TC的带宽, 进一歩包括所述 0NU采用 0NU响应时间解析所述 BWmap , 其中, 所述 0NU响应时间大 于 36 us , 所述 ONU响应时间用于标识所述 ONU电路延迟时间。 在第三方面的第二种可能的实现方式中,所述 0NU响应是由所述 0LT下发给所述 0NU的 0NU响应时间; 或者, 所述 0NU响应时间是所 述 0NU自身配置的的 0NU响应时间。
在第三方面的第三种可能的实现方式中,所述 0NU响应时间是所 述 0LT根据端口下连接的所述 TC的个数, 或所述 BWmap能携带的最 大所述传输容器个数计算得出的。
在第三方面的第四种可能的实现方式中,所述解析单元用于解析 所述 BWmap , 获得分配给所述 ONU的所述 TC的带宽, 进一歩包括所述 0NU根据等效延迟时间 EQD解析所述 BWmap , 其中, 所述 EQD为所述 0LT下发给所述 0NU, 所述 EQD用于标识所述 0LT端口距离和所述 0NU 的距离所述 EQD为 125微秒的一倍或多个整数倍。
在第三方面的第五种可能的实现方式中,所述解析单元用于解析 所述 BWmap , 获得分配给所述 ONU的所述 TC的带宽, 进一歩包括所述 0NU根据带宽起始时间 StartTime解析所述 BWmap , 其中, 所述
StartTime为所述 0LT下发给所述 0NU, 所述 StartTime用于标识分 配给所述 TC的发光时隙在所述 BWmap中的位置所述 StartTime为 125微秒的一倍或多个整数倍。
第四方面, 一种光线路终端, 所述 0LT包括发送单元, 用于发 送多个下行帧,每个下行帧中携带带宽分配位图 BWmap ,所述 BWmap 包括为 N个所述 TC分配带宽的 N个子字段, 其中, N为大于 512的整 数; 接收单元, 用于接收所述 0NU根据解析所述 BWmap获得的所述 TC的带宽发送的上行数据。 在第四方面的第一种可能的实现方式中, 发送单元还用于下 发 0NU响应时间至所述 0NU, 其中, 所述 0NU响应时间用于 0NU解析 所述 BWmap , 所述 ONU响应时间用于标识所述 ONU的电路延迟时间。
在第四方面的第二种可能的实现方式中, 所述 0NU响应时间是 所述 0LT根据端口下连接的所述 TC的个数, 或所述 BWmap能携带的 最大所述 TC个数计算得出的。
在第四方面的第三种可能的实现方式中, 发送单元还用于下 发等效延迟时间 EQD至所述 0NU, 所述 EQD用于所述 0NU解析所述 BWmap , 所述 EQD用于标识所述 EQD用于标识所述 0LT端口距离和所 述 0NU的距离, 所述 EQD为 125微秒的一倍或多个整数倍。
在第四方面的第四种可能的实现方式中, 发送单元还用于下 发带宽起始时间 StartTime至所述 0NU, 所述 StartTime用于所述 0NU解析所述 BWmap , 所述 StartTime用于标识分配给所述 TC的发光 时隙在所述 BWmap中的位置, 所述 StartTime为 125微秒的一倍或多 个整数倍。
第五方面, 一种无源光网络系统, 包括如第三方面任意一种 可能的实现方式中所述的光网络单元和如第四方面任意一种可能 的实现方式中所述的光线路终端。
通过以上技术方案, 0LT每帧分配带宽的个数可以从 512扩大到 2047, 显著缩短了分配周期, 降低对 0NU缓存的要求, 进而也降低了 0NU所承载的时分复用等业务时延, 提高了用户满意度。
附图说明 为了更清楚地说明本发明的实施例或现有技术中的技术方案,下 面将对描述背景技术和实施例时所使用的附图作简单的介绍。显而易 见地, 下面附图中描述的仅仅是本发明的一部分实施例, 对于本领域 普通技术人员来讲, 在不付出创造性劳动的前提下, 还可以根据这些 附图和描述得到其他的附图或实施例,而本发明旨在涵盖所有这些衍 生的附图或实施例。
图 1是本发明实施例基于的网络架构示意图;
图 2是本发明实施例提供的 GTC帧结构示意图;
图 3是本发明实施例提供的 0LT下发 BWmap示意图;
图 4是本发明实施例提供的 0NU解析 BWmap示意图;
图 5 是本发明实施例的提供的一种无源光网络上行带宽分配的 方法流程示意图;
图 6是本发明实施例提供的 0NU注册认证流程示意图;
图 7是本发明实施例提供的一种光网络单元的结构示意图; 图 8是本发明实施例提供的一种光线路终端的结构示意图。
具体实施方式
为了使本发明的目的、技术方案及优点更加清楚明白, 以下结合 附图及实施例, 对本发明进行进一歩详细说明。 应当理解, 此处所描 述的具体实施例仅仅用以解释本发明, 并不用于限定本发明。 显然, 所描述的实施例仅仅是本发明一部分实施例, 而不是全部的实施例。 基于本发明中的实施例,本领域普通技术人员在没有做出创造性劳动 前提下所获得的所有其他实施例, 都属于本发明保护的范围。 图 1为本发明实施例所基于的 GP0N光网络架构示意图。 在图 1 的 GP0N光网络系统 PON (Passive Optical Network,无源光网络)中, 多个光网络终端 (Optical Network Terminal , 0NT) 或光网络单元
( Optical Network Unit , ONU ) , 通过光分布网络 (Optical Distribution Network , ODN)连接到光线路终端 (Optical Line Terminal , 0LT)。 OLT为 PON系统提供网络侧接口, 连接一个或多个 0DN。 ODN是无源光分器件, 将 0LT下行的数据分路传输到各个 0NU, 同时将多个 0NU/0NT的上行数据汇总传输到 0LT。 ONU为 PON系统提 供用户侧接口, 上行与 0DN相连, 如果 0NU直接提供用户端口功能, 如 PC (Personal Computer,个人计算机)上网用的以太网用户端口, 则称为 0NT, 下文提到的 0NU统指 0NU和 0NT。
ONU到 OLT的上行传输采用多点到点的方式, 0LT到 0NU的下行 传输采用点到多点的方式。图 1中所示的 TCXTransmission Container, 传输容器) 1, TC2, TC3等表示 GP0N系统定义的传输容器, 每一个 0NU可以被分配一个或多个 TCs以输出数据, 其中, 不同业务类型通 过不同的 TC传输到 0LT。
在 GP0N系统中, 下行方向 (由 0LT到 0NU方向) 的数据传输采 用广播方式, 每个 0NU 分别接收所有的下行帧, 再根据 0NU标识
( 0NU_ID )、 吉比特无源光网络封装方法的端口标识 (GP0N Encapsulate Method portID , GEM-portID ) 或者分酉己标识
(Al location Identifier, Alloc-ID) 来获取属于自己的帧。 对于 上行方向 (从 0NU到 0LT方向) 的数据传输, 由于各个 0NU需要共享 传输媒质, 因此各个 ONU在 OLT通过上行带宽分配位图(Band-Width map, BWmap )分配给自己的时隙内传输上行数据, 其中 BWmap携带在 所述的下行帧中。
其中, 所述的下行帧可以为 GP0N传输汇聚 (GPON Transmission Convergence , GTC )帧。 所述 GTC帧包括同歩域、 超帧指示域、 消息 处理域、 比特间插奇偶校验码域、 下行有效载荷长度域、 和带宽分配 位图以及负载。 可选地, 下面描述的实施例可以应用在 GP0N系统中, 也可以应用在 十吉比特无源光网络 ( 10-Gigabit-capable Passive Optical Network, XG-PON) 系统中。 进一歩的, 下面实施例描述的下行帧可 以为所述 GTC帧, 也可以为 XG-P0N传输汇聚(XG-PON transmission convergence, XGTC) 帧。 其中, 如图 2所示, 所述的 GTC帧结构用于标识 0LT通过下行帧 中的带宽分配位图 BWmap对 0NU的各个业务类型 TC进行授权, 开始 时间字段和结束时间字段分别用于标识 ID为 Al loc- ID的 TC的发送 上行光信号的开始时间和停止时间 (以字节为单位)。
进一歩地, BWmap 的结构如图 3所述, BWmap有 N个分配结构 (Al location Structure ) 组成, 其中, N为自然数。 每个分配结构 由带宽分配标识 (Al loc-ID ) , 带宽起始时间 (Start Time ) , 分配带 宽(Grant Size ) ,其中, Al loc-ID用于标识传输容器 (Transmission Container, T- C0NT) 的 ID; 宽带起始时间 Start Time是一个 16位 比特的字符串, 用于标识分配时隙在本帧中的位置; 分配带宽 Grant Size用于标识带宽分配位图 BWmap给所述传输容器分配的字节数。
0LT连接的所有 0NU接收所述携带 BWmap的下行帧后, 各自解析 BWmap后, 各自在 BWmap指定的时隙发送上行光。
根据标准 G987. 3所述, 如图 4所示, 0NU从接收到收 BWmap到 发送上行光的时间包括:
第一, 0NU响应时间 ( ResponseTime , Rsptime ) , 用于标识 ONU 接收 BWmap的电路时延, 根据标准 G987. 3的规定, 为 35 ± 1 s ; 第二, 等效延迟时间 (Equal ization Delay, EQD) , 取决于 OLT 端口距离范围和 ONU的距离, 可能为 0;
第三, 带宽起始时间 (Start Time ) , 取决于分配时隙在本帧中 的位置, 可能为 0。
0NU需要在上述时间内完成 BWmap解析。 下面我们将结合具体的 发明实施例来详细说明。
实施例一
为方便介绍, 本发明对光线路终端简称 0LT, 对光网络单元简称 0NU, 下面对本发明实施方式提供的一种无源光网络上行带宽分配的 方法进行详细说明, 如图 5所示。
S501 , 0LT向 0NU发送广播报文, 该广播报文携带 BWmap, 其中 每帧 BWmap为 N个 TC分配带宽, N为大于 512的自然数, 0NU接收来 自 0LT的所述携带 BWmap的广播报文。
其中, N的最大值为 2047。
进一歩地, 在 S501歩骤之前, 首先, 0LT要在 0NU上线注册过 程中, 发送广播报文至 0NU, 这里的 0NU上线注册过程如图 6所示, 包含 5个过程, 具体可以参见 IEEE制定的 G987. 3标准:
( 1 ) 0NU首先处于 01状态, 此状态为准备态;
(2 ) 同歩到下行帧以后, 进入 02/03状态;
( 3) 0LT 定期发送概要信息 (Profile Message ) , 并定期分配 序列码 SN上报带宽; Profile Message中有定界符、前导码等信息; 0NU收到 Profile Message后, 在上报序列码 SN的周期内上报 SN;
(4) 0LT收到 0NU上报的 SN以后,发现 0NU,分配 0NU标识 0NU- ID; 0NU收到 0NU-ID以后, 进入 04状态;
(5 ) 0LT分配测距带宽; 0NU响应测距消息; 0LT下发等效延迟 时间 EQD; 0NU进入 05状态, 上线完成;
所述的广播报文可以通过物理层操作和管理消息 (Physical Layer Organization and Management, PL0AM) 消息发送, 还可以自 定义一个新的消息进行发送,本发明实施例不限于具体采用的消息报 文。
进一歩地,所述的广播报文携带有概要信息(Profile Message ), 这里的概要信息为 G987. 3标准规定的, 0NU在注册认证过程中需要 上报给 0LT的参数信息, 其中, 所述的概要信息中携带 0NU响应时间 (0NU Response time, RspTime), 该响应时间可以是 0LT根据端口 下连接的 TC个数,或者 BWmap能携带的最大 TC个数,计算解析 BWmap 所需的 Response time, 这里的最大 TC个数为 2047个, 这里的计算 解析是 0LT根据实际连接的 TC个数测算得出, 实际测算的 0NU响应 时间的数值范围是 6(T70us, 本发明并不限定具体的 0NU响应时间的 数值范围。
其中, RspTime是 0NU响应时间, N为实际的 TC的个数; 进一歩地, 具体的 Profile message结构可以如表 1所示: 表 1 Profile message报文内容
Figure imgf000014_0001
计算出 0NU响应时间 (Response time, RspTime) 后, OLT通过 所述的广播报文下发至 0LT;
然后, 0LT通过 BWmap每帧下发大于 512个 TC的带宽至 0NU。 S502, 所述 ONU解析所述 BWmap, 获得分配给所述 ONU的所述传 输容器的带宽。
其中,根据标准 G987. 3规定, 0NU解析报文的时间有三个部分: 0NU 响应时间 (ONU response time , RspTime ) , 等效延迟时间 (Equalization Delay, EQD), 带宽起始时间 ( Start Time )。
在本歩骤中, ONU根据接收的所述广播报文中携带的 0NU响应 时间解析 BWmap, 而不是标准 G987. 3规定的 35± 1 s; 等效延迟 时间和带宽起始时间均按照标准 G987. 3的规定操作。
S503, 所述 0NU根据获得的所述 TC的带宽发送上行数据, 所 述 0LT接收所述上行数据。
通过以上技术方案,每帧分配带宽的个数可以从 512扩大到 2047, 显著缩短了分配周期, 降低对 0NU缓存的要求, 进而也降低了 0NU所 承载的时分复用等业务时延, 提高了用户满意度。 实施例二
本发明实施例还提供了一种无源光网络上行带宽分配的方法, 首先, 0LT向 0NU发送广播报文, 该广播报文携带 BWmap, 其中 每帧 BWmap为 N个 TC分配带宽, N为大于 512的自然数;
其中, N的最大值为 2047。
所述的广播报文可以通过物理层操作和管理消息 (Physical Layer Organization and Management, PLOAM) 消息发送, 还可以自 定义一个新的消息进行发送,本发明实施例不限于具体采用的消息报 文。
第二, 0NU根据所述 BWmap分配的 N个传输容器总带宽大小组装 上行数据并发送至 0LT。
其中,本发明实施例是 0NU并不采用现有标准 G987. 3规定的 0NU 响应时间, 而是采用实际测算的 0NU响应时间, 以能够解析大于 512 个 TC的 BWmap。
其中,所述的实际测算的 0NU响应时间是 0LT根据端口下连接的 TC个数, 或者 BWmap能携带的最大 TC个数, 计算解析 BWmap所需的 Response time , 这里的最大 TC个数为 2047个, 这里的计算解析是 0LT根据实际连接的 TC个数测算得出, 实际测算的 0NU响应时间的 数值范围是 6(T70us, 本发明并不限定具体的 0NU响应时间的数值范 围。
可选地, 等效延迟时间和带宽起始时间均按照标准的规定操作。 通过以上技术方案,每帧分配带宽的个数可以从 512扩大到 2047, 显著缩短了分配周期, 降低对 0NU缓存的要求。
实施例三
本发明实施例还提供了一种无源光网络上行带宽分配方法, 首先, 0LT向 0NU发送广播报文, 该广播报文携带 BWmap , 其中 每帧 BWmap为 N个 TC分配带宽, N为大于 512的自然数;
其中, N的最大值为 2047。
其中, 在此歩骤之前, 0LT要在 0NU注册认证过程中, 发送广 播报文至 0NU,这里的 0NU注册认证过程如图 6所示,包含 5个过程, 具体可以参见 G987. 3标准:
( 1 ) ONU首先处于 01状态, 此状态为准备态;
(2 ) 同歩到下行帧以后, 进入 02/03状态;
( 3) 0LT 定期发送概要信息 "Profile Message", 并定期分配 序列码 SN上报带宽; "Profile Message" 中有定界符、 前导码等信 息; 0NU收到 "Profile Message"后, 在上报序列码 SN的周期内上 报 SN;
(4) 0LT收到 0NU上报的 SN以后,发现 0NU,分配 0NU标识 0NU- ID; 0NU收到 0NU-ID以后, 进入 04状态;
(5 ) 0LT分配测距带宽; 0NU响应测距消息; 0LT下发等效延迟 时间 EQD; 0NU进入 05状态, 上线完成;
所述的广播报文可以通过物理层操作和管理消息 (Physical Layer Organization and Management, PL0AM) 消息发送, 还可以自 定义一个新的消息进行发送,本发明实施例不限于具体采用的消息报 文。
进一歩地, 0LT在上述 04状态测距之后, 下发等效延迟 EQD至 0NU, 这里的等效延迟 EQD固定增加一个或多个周期, 所述的一个周 期为 125us, 即 0LT下发给 0NU的等效延迟时间 EQD在现有基础上固 定增加 125us的整数倍,使得 0NU有足够的时间可以解析 BWmap报文。
其中, 所述的 EQD 可以根据如下公式计算得出, 可以参见标准 G987. 3第 64页的规定, 具体如下:
Tead≥ RspTim + ( min + Dm
Figure imgf000017_0001
其中, Teqd用于标识所述等效延迟时间与往返延迟 (Round Trip Delay, RTD) 的和, 根据距离最远的 ONU计算, 并对齐到 125us的整 数倍,
RspTimemax根据标准 G987. 3的规定, RspTime为 35 ± 1 μ s , 因 此为 RspTime隨为 36us,,
Lmin用于标识最小距离, Dmax用于标识最小距离和最大距离的距离 差,
n1577、 n127。分别用于标识上行和下行的折射率,
c用于标识光速;
所述的广播报文可以通过物理层操作和管理消息 (Physical Layer Organization and Management , PLOAM) 消息发送, 还可以自 定义一个新的消息进行发送,本发明实施例不限于具体采用的消息报 文。
第二, 0NU根据所述 BWmap分配的 N个传输容器总带宽大小组装 上行数据并发送至 0LT。
在本歩骤中, 0NU根据接收的所述广播报文中携带的所述等效延 迟时间解析 BWmap; 0NU响应时间采用标准 G987. 3规定的 35 ± 1 μ s, 带宽起始时间按照标准 G987. 3的规定操作。
通过以上技术方案,每帧分配带宽的个数可以从 512扩大到 2047, 显著缩短了分配周期, 降低对 0NU缓存的要求, 进而也降低了 0NU所 承载的时分复用等业务时延, 提高了用户满意度。
实施例四 本发明实施例还提供了一种无源光网络上行带宽分配方法, 首先, 0LT向 0NU发送广播报文, 该广播报文携带 BWmap, 其中 每帧 BWmap为 N个 TC分配带宽, N为大于 512的自然数;
其中, N的最大值为 2047。
所述的广播报文可以通过物理层操作和管理消息 (Physical Layer Organization and Management, PLOAM) 消息发送, 还可以自 定义一个新的消息进行发送,本发明实施例不限于具体采用的消息报 文。
进一歩地, 在 0LT下发给 0NU的广播消息中, 每帧的 BWmap的带 宽起始时间 StartTime固定增加一个或多个周期,所述的一个周期为 125us, g卩 0LT下发给 0NU的广播消息中, BWmap中携带的 StartTime 在现有基础上固定增加 125us的整数倍,使得 0NU有足够的时间可以 解析 BWmap报文。
第二, 0NU根据接收的所述广播报文中携带的所述带宽起始时间 解析 BWmap, 并发送上行光。 通过以上技术方案,每帧分配带宽的个数可以从 512扩大到 2047, 显著缩短了分配周期, 降低对 0NU缓存的要求。 实施例五 本发明实施例提供了一种光网络单元 0NU, 如图 7所示, 包括: 接收单元 710, 用于接收来自 0LT的多个下行帧, 每个所述下行 帧携带带宽分配位图 BWmap, 所述 BWmap包括为 N个所述 TC分配带宽 的 N个子字段, 其中, N为大于 512的整数; 解析单元 720, 用于解析所述 BWmap , 获得分配给所述 0NU的所 述 TC的带宽; 发送单元 730, 用于根据获得的所述 TC的带宽发送上行数据。 其中, 所述 0NU采用 0NU响应时间解析所述 BWmap , 其中, 所述
0NU响应时间大于 36 us , 所述 0NU响应时间用于标识所述 0NU电路 延迟时间。
或者, 所述 0NU根据等效延迟时间 EQD解析所述 BWmap, 其中, 所述 EQD为所述 0LT下发给所述 0NU, 所述 EQD用于标识 所述 0LT端口距离和所述 0NU的距离所述 EQD为 125微秒的一倍或多 个整数倍。
或者, 所述 0NU根据带宽起始时间 StartTime解析所述 BWmap , 其中, 所述 StartTime为所述 0LT下发给所述 0NU, 所述
StartTime用于标识分配给所述 TC的发光时隙在所述 BWmap中的位 置所述 StartTime为 125微秒的一倍或多个整数倍。
进一歩地, 所述 0NU响应是由所述 0LT下发给所述 0NU的 0NU响 应时间; 或者, 所述 0NU响应时间是所述 0NU自身配置的的 0NU响应 时间。
进一歩地, 所述 0NU响应时间是所述 0LT根据端口下连接的所 述 TC的个数, 或所述 BWmap能携带的最大所述传输容器个数计算得 出的。
其中, 所述 BWmap能携带的最大所述传输容器个数为 2047。
实施例六 本发明实施例提供了一种光线路终端 0LT, 如图 8所示, 包括: 发送单元 810, 用于发送多个下行帧, 每个下行帧中携带带宽 分配位图 BWmap , 所述 BWmap包括为 N个所述 TC分配带宽的 N个子字 段, 其中, N为大于 512的整数;
接收单元 820, 用于接收所述 0NU根据解析所述 BWmap获得的所 述 TC的带宽发送的上行数据。 其中, 0LT下发 0NU响应时间至所述 0NU , 其中, 所述 0NU响应时间用于 0NU解析所述 BWmap , 所述 ONU响 应时间用于标识所述 ON U的电路延迟时间。
进一歩地, 发送单元还用于下发等效延迟时间 EQD至所述 0NU, 所述 EQD用于所述 0NU解析所述 BWmap , 所述 EQD用于标识所述 EQD用 于标识所述 0LT端口距离和所述 0NU的距离, 所述 EQD为 125微秒的 一倍或多个整数倍。
进一歩地, 发送单元还用于下发带宽起始时间 StartTime至所 述 0NU , 所述 StartTime用于所述 0NU解析所述 BWmap , 所述
StartTime用于标识分配给所述 TC的发光时隙在所述 BWmap中的位 置, 所述 StartTime为 125微秒的一倍或多个整数倍。
进一歩地, 所述 0NU响应时间是所述 0LT根据端口下连接的所 述 TC的个数, 或所述 BWmap能携带的最大所述 TC个数计算得出的。
其中, 所述 BWmap能携带的最大所述传输容器个数为 2047。
实施例七
一种无源光网络中带宽分配的系统,包括光线路终端和光网络单 元, 其中, 光线路终端用于通过上行带宽分配位图为所述光网络单元 分配带宽, 其中, 每帧所述带宽分配位图为 N个传输容器分配带宽, 所述 N为大于 512的自然数;
所述光网络单元, 用于根据所述光线路终端分配的所述 N个传输 容器总带宽大小组装上行数据并发送给所述光线路终端。
所述光线路终端还用于下发广播报文至所述光网络单元, 所 述广播报文携带第一解析时间, 所述第一解析时间用于标识所述 光网络单元解析所述 N个传输容器所需的时间; 所述第一解析时间 是所述光线路终端根据连接的所述传输容器的个数, 或者所述每 帧带宽分配位图能携带的最大传输容器的个数计算得出。
具体所述光网络单元的详细描述可以参见实施例五中对光网 络单元的描述, 所述光线路终端的详细描述可以参见实施例六中 光线路终端的描述。 进一歩地, 所述无源光网络中带宽分配的系统 中所述光线路终端与所述各光网络单元的交互流程可以参见实施例 一至实施例四种上行带宽分配的方法的详细描述, 这里就不再赘述 了。
通过以上技术方案, 0LT每帧分配带宽的个数可以从 512扩大到 2047, 显著缩短了分配周期, 降低对 0NU缓存的要求, 进而也降低了 0NU所承载的时分复用等业务时延, 提高了用户满意度。
通过以上的实施方式的描述, 本领域的技术人员可以清楚地 了解到本发明可借助软件加必需的硬件平台的方式来实现, 当然 也可以全部通过硬件来实施。 基于这样的理解, 本发明的技术方 案对背景技术做出贡献的全部或者部分可以以软件产品的形式体 现出来, 该计算机软件产品可以存储在存储介质中, 如 R0M/RAM、 磁碟、 光盘等, 包括若干指令用以使得一台计算机设备 (可以是 个人计算机, 服务器, 或者网络设备等) 执行本发明各个实施例 或者实施例的某些部分所述的方法。
以上所述仅为本发明的几个实施例, 本领域的技术人员依据 申请文件公开的可以对本发明进行各种改动或变型而不脱离本发 明的精神和范围。

Claims

权 利 要 求 书
1、 一种带宽分配方法, 所述带宽分配的方法应用于无源光网 络系统中, 所述系统包括光线路终端 0LT和至少一个光网络单元 0NU , 所述任意一个光网络单元 0NU支持多个传输容器 TC, 其特征 在于, 所述方法包括:
所述 0NU接收来自所述 0LT的下行帧, 每个所述下行帧携带带 宽分配位图 BWmap , 所述 BWmap包括为 N个所述 TC分配带宽的 N个子 字段, 其中, N为大于 512的整数;
所述 0NU解析所述 BWmap , 获得分配给所述 ONU的所述 TC的带 宽;
所述 0NU根据获得的所述 TC的带宽发送上行数据。
2、 如权利要求 1所述的方法, 其特征在于, 所述 0NU解析所述 BWmap , 进一歩包括:
所述 0NU采用 0NU响应时间解析所述 BWmap , 其中, 所述 0NU口向 应时间大于 36 us , 所述 ONU响应时间用于标识所述 ONU电路延迟时 间。
3、 如权利要求 2所述的方法, 其特征在于, 所述 0NU响应时间 是由所述 0LT下发给所述 0NU的 0NU响应时间 ·'
或者, 所述 0NU响应时间是所述 0NU自身配置的的 0NU响应时 间。
4、 如权利要求 2或 3所述的方法, 其特征在于, 所述 0NU响应 时间是所述 OLT根据端口下连接的所述 TC的个数, 或所述 BWmap能 携带的最大所述传输容器个数计算得出的。
5、 如权利要求 1所述的方法, 其特征在于, 所述 0NU解析所述 BWmap , 进一歩包括:
所述 0NU根据等效延迟时间 EQD解析所述 BWmap ,
其中, 所述 EQD为所述 0LT下发给所述 0NU, 所述 EQD用于标识 所述 0LT端口距离和所述 0NU的距离, 所述 EQD为 125微秒的一倍或 多个整数倍。
6、 如权利要求 1所述的方法, 其特征在于, 所述 0NU解析所述 BWmap , 进一歩包括:
所述 0NU根据带宽起始时间 StartTime解析所述 BWmap , 其中, 所述 StartTime为所述 0LT下发给所述 0NU, 所述
StartTime用于标识分配给所述 TC的发光时隙在所述 BWmap中的位 置, 所述 StartTime为 125微秒的一倍或多个整数倍。
7、 一种带宽分配方法, 其特征在于, 所述带宽分配的方法应 用于无源光网络系统 P0N中, 所述系统 P0N包括光线路终端 0LT和至 少一个光网络单元 0NU, 所述任意一个光网络单元 0NU支持多个传 输容器 TC, 其特征在于, 所述方法包括:
所述光线路终端 0TL发送多个下行帧, 每个下行帧中携带带宽 分配位图 BWmap , 所述 BWmap包括为 N个所述 TC分配带宽的 N个子字 段, 其中, N为大于 512的整数; 接收所述 ONU发送的上行数据,其中,所述上行数据是所述 0NU 按照解析所述 BWmap获得的带宽来组装的。
8、 如权利要求 7所述的方法, 其特征在于, 所述方法还包括: 所述 0LT下发 0NU响应时间至所述 0NU,
其中, 所述 0NU响应时间用于 0NU解析所述 BWmap , 所述 ONU口向 应时间用于标识所述 ON U的电路延迟时间。
9、 如权利要求 8所述的方法, 其特征在于, 所述 0NU响应时间 是所述 0LT根据端口下连接的所述 TC的个数, 或所述 BWmap能携带 的最大所述 TC个数计算得出的。
10、如权利要求 7所述的方法, 其特征在于, 所述方法还包括: 所述 0LT下发等效延迟时间 EQD至所述 0NU, 其中,
所述 EQD用于所述 0NU解析所述 BWmap, 所述 EQD用于标识所述 0LT端口距离和所述 0NU的距离, 所述 EQD为 125微秒的一倍或多个 整数倍。
11、如权利要求 7所述的方法, 其特征在于, 所述方法还包括: 所述 0LT下发带宽起始时间 StartTime至所述 0NU, 其中, 所述 StartTime用于所述 0NU角早析所述 BWmap , 所述 StartTime 用于标识分配给所述 TC的发光时隙在所述 BWmap中的位置, 所述 StartTime为 125微秒的一倍或多个整数倍。
12、 一种光网络单元, 其特征在于, 包括: 接收单元, 用于接收来自 0LT的多个下行帧, 每个所述下行帧 携带带宽分配位图 BWmap , 所述 BWmap包括为 N个所述 TC分配带宽的 N个子字段, 其中, N为大于 512的整数;
解析单元, 用于解析所述 BWmap , 获得分配给所述 0NU的所述 TC 的带宽;
发送单元, 用于根据获得的所述 TC的带宽发送上行数据。
13、 如权利要求 12所述的光网络单元, 其特征在于, 所述解析单 元用于解析所述 BWmap , 获得分配给所述 0NU的所述 TC的带宽, 进一 歩包括:
所述 0NU采用 0NU响应时间解析所述 BWmap , 其中, 所述 0NU口向 应时间大于 36 us , 所述 0NU响应时间用于标识所述 0NU电路延迟时 间。
14、 如权利要求 13所述的光网络单元, 其特征在于, 所述 0NU 响应是由所述 0LT下发给所述 0NU的 0NU响应时间;
或者, 所述 0NU响应时间是所述 0NU自身配置的的 0NU响应时 间。
15、 如权利要求 13或 14所述的光网络单元, 其特征在于, 所 述 0NU响应时间是所述 0LT根据端口下连接的所述 TC的个数, 或所 述 BWmap能携带的最大所述传输容器个数计算得出的。
16、 如权利要求 12所述的光网络单元, 其特征在于, 所述解析 单元用于解析所述 BWmap , 获得分配给所述 0NU的所述 TC的带宽, 进 一歩包括: 所述 ONU根据等效延迟时间 EQD解析所述 BWmap , 其中, 所述 EQD为所述 0LT下发给所述 0NU , 所述 EQD用于标识 所述 0LT端口距离和所述 0NU的距离所述 EQD为 125微秒的一倍或多 个整数倍。
17、 如权利要求 12所述的光网络单元, 其特征在于, 所述解析 单元用于解析所述 BWmap , 获得分配给所述 ONU的所述 TC的带宽, 进 一歩包括:
所述 0NU根据带宽起始时间 StartTime解析所述 BWmap ,
其中, 所述 StartTime为所述 0LT下发给所述 0NU, 所述
StartTime用于标识分配给所述 TC的发光时隙在所述 BWmap中的位 置所述 StartTime为 125微秒的一倍或多个整数倍。
18、 一种光线路终端 0LT , 其特征在于, 所述 0LT包括: 发送单元, 用于发送多个下行帧, 每个下行帧中携带带宽分 配位图 BWmap , 所述 BWmap包括为 N个所述 TC分配带宽的 N个子字段, 其中, N为大于 512的整数;
接收单元, 用于接收所述 0NU根据解析所述 BWmap获得的所述 TC的带宽发送的上行数据。
19、如权利要求 18所述的 0LT , 其特征在于, 发送单元还用于: 下发 0NU响应时间至所述 0NU,其中,所述 0NU响应时间用于 0NU 解析所述 BWmap , 所述 ONU响应时间用于标识所述 ONU的电路延迟时 间。
20、 如权利要求 18所述的 OLT, 其特征在于, 所述 0NU响应时 间是所述 0LT根据端口下连接的所述 TC的个数, 或所述 BWmap能携 带的最大所述 TC个数计算得出的。
21、如权利要求 18所述的 0LT, 其特征在于, 发送单元还用于: 下发等效延迟时间 EQD至所述 0NU, 所述 EQD用于所述 0NU解析 所述 BWmap, 所述 EQD用于标识所述 EQD用于标识所述 0LT端口距离 和所述 0NU的距离, 所述 EQD为 125微秒的一倍或多个整数倍。
22、如权利要求 18所述的 0LT, 其特征在于, 发送单元还用于: 下发带宽起始时间 StartTime至所述 0NU, 所述 StartTime用于 所述 0NU解析所述 BWmap , 所述 StartTime用于标识分配给所述 TC的 发光时隙在所述 BWmap中的位置, 所述 StartTime为 125微秒的一倍 或多个整数倍。
23、 一种无源光网络系统, 其特征在于, 所述系统包括如权利要 求 18 2任意一项所述的光线路终端和如权利要求 12^17任意一项所 述的光网络单元。
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