Method for data transmission and system for gigabit passive optical network

TECHNICAL FIELD The present invention relates to the field of communication, in particular to the method of data transmission and the gigabit system of a passive optical network.

Prior art [0002] Gigabit passive optical network (GPON) technology is an important technical field of the passive optical network (PON) family, and like other PON technologies, GPON is also a passive optical access technology that applies point-to-multipoint topology.

[0003] Fig. 1 is a topology diagram of a GPON system according to the prior art. As shown in Fig. 1, the GPON includes an optical line end (OLT) on the office side, an optical network unit (ONU) on the subscriber's side and a distribution optical network (ODN) and typically uses the point-to-point network structure. ODN includes such passive optical devices as single-mode optical fiber, optical splitter, optical connector and the like, and provides an optical transmission medium for the physical connection between OLT and ONU.

[0004] In the GPON system, down data transmission (from OLT to ONU) applies the broadcasting method, and each ONU receives all frames accordingly, and then acquires its own frames based on the identification of the optical network unit (ONU-ID), port identification of the encapsulation method. GPON (GEM-ID port) and allocation ID.

[0005] Fig. 2 shows a schematic diagram of a GPON frame structure downwards according to the prior art. As shown in FIG. 2, the GPON down frame includes the physical control block of the forward channel (PCBd) and the data block. The data block contains a plurality of GPON encapsulation frame (GEM) headers and GEM data blocks. The GEM header contains four parts, which are the data block length indicator (PLI), port identifier, data block type indicator (PTI) and header error (HEC) check.

[0006] In downlinking, after receiving the GEM frame transmitted by the OLT, the ONU first performs the HEC check. If the result of the HEC check is incorrect, then the ONU rejects the GEM frame, and if the result of the HEC check is correct, the ONU judges whether the GEM frame is transmitted to itself based on the port identifier in the header of the GEM frame. If it judges that the frame is not transmitted to itself, then the ONU rejects the GEM frame, and if it judges that the frame is transmitted to itself, the ONU receives the content of the GEM data block corresponding to that GEM frame header.

[0007] In the uplink direction, after receiving the GEM frame transmitted by the ONU, the OLT first performs the HEC check. If the result of the HEC check is incorrect, then the OLT discards the GEM frame, and if the result is correct, then the OLT receives the content of the GEM data block corresponding to the GEM frame header.

[0008] When the transmitter does not want the receiver to receive data at a predetermined time, for example, when the OLT does not have an adequate amount of data to transmit to the ONU, or the ONU does not have an adequate amount of data to transmit to the OLT, the existing prior art uses the transmitter method of transmitting to the receiver, idle frames in which the idle frame is the header of the GEM frame, the value of which is 0xB6AB31E055, and because the length of the idle frame is relatively shorter, the receiver must solve the idle frames one by one and the performance is rather small.

[0009] The prior art does not provide an efficient method for handling an idle band, for example a method for transmitting a GEM frame transmitter by a transmitter and a method for solving a received GEM frame by a receiver.

[0010] In document T01020006350701 MSWE-LC-edited-marked-dkh ", ITU-T DRAFT; STUDY PERIOD 2005-2008, INTERNATIONAL TELECOMMUNICATION UNION, GENEVA; CH, vol. Study Group 15, 22 February 2004 (2004-02 22 ), pages 1-147, XP017528620, [refined 2008-04-05] "appropriate technical solutions were provided; however, the problem mentioned above remains unresolved.

Summary of the Invention [0011] The invention has been proposed for such a problem that there is no effective way of handling the idling band provided in the prior art. To this end, one object of the invention is to provide a data transmission solution to solve the above problem.

[0012] To achieve the above objective, the method of data transmission is provided according to one embodiment of the invention.

[0013] The data transmission method according to one embodiment of the invention comprises: a transmitter carrying indication information in an uplink or downlink frame transmitted to the receiver to enable the receiver to reject information in the uplink or downlink frame that does not need to be processed by the receiver based on indication information.

[0014] Furthermore, the transmitter carries information that does not need to be processed by the receiver in the Gigabit passive frame network (GEM) encapsulation frame of the uplink frame or downlink, where the port indication value in the header of the GEM frame is a predetermined value , it indicates that the GEM frame carries information that does not need to be processed by the receiver.

[0015] Further, a receiver that rejects information that does not need to be processed by the receiver in the uplink or downlink frame includes: a receiver evaluating whether the port indication value in the header of the uplink frame or downlink frame is a predetermined value , and if the result of the evaluation is YES, rejecting the GEM frame whose value of the port indication in the frame header is a predetermined value. [0016] Furthermore, the transmitter carries information that does not need to be processed by the receiver in a pre-set GEM frame of the uplink frame or downlink, where the value of the data block type in the frame header of the predetermined GEM frame is a predetermined value, it indicates that the GEM frame carries information that does not need to be processed by the receiver.

[0017] Furthermore, a receiver rejecting information in an uplink or downlink frame that does not need to be processed by the receiver includes: an evaluating receiver whether the value of the data block type in the header of the uplink frame or downlink frame GEM is a predetermined value , and if the result of the evaluation is YES, rejecting the GEM frame whose value of the data block type in the frame header is a predetermined value. [0018] To achieve the above object, a gigabit optical network system according to a further aspect of the invention is provided.

[0019] The gigabit passive optical network system according to a further embodiment of the invention comprises: a transmitter and a receiver, wherein the receiver is an optical network unit in the case where the transmitter is the end of the optical line; or the receiver is the end of the optical line in the case where the transmitter is an optical network unit, the transmitter carries the indication information in the uplink or downlink frame transmitted to the receiver to allow the receiver to reject information in the uplink frame or downlink that do not need to be be processed by the receiver based on indication information.

[0020] Furthermore, the transmitter carries information that does not need to be processed by the receiver in the gigabit passive optical network (GEM) encapsulation frame of the uplink frame or downlink, while

When the value of the port identification in the header of the GEM frame is a predetermined value, it indicates that the GEM frame carries information that does not need to be processed by the receiver.

[0021] Further, the receiver judges whether the port identification value in the header of the uplink frame or downlink frame GEM is a predetermined value, and if the evaluation results in YES, discards the GEM frame whose port identification value in the frame header is in advance fixed value.

[0022] Furthermore, the transmitter carries information that does not need to be processed by the receiver in a pre-set GEM frame of the uplink frame or downlink, where the value of the data block type in the frame header of the predetermined GEM frame is a predetermined value, it indicates that the GEM frame carries information that does not need to be processed by the receiver.

[0023] Further, the receiver judges whether the data block type value in the header of the uplink frame or down link frame GEM is a predetermined value, and if the evaluation result is YES, discards the GEM frame whose value of the data block type in the frame header is predetermined value.

[0024] By means of the invention, the problem that an effective method is not provided in the prior art is solved by using a transmitter for transmission to a data receiver that does not need to be processed by the receiver, thus expanding the data type transmitted by the GPON system and allows you to effectively operate the idle band.

[0025] Other features and advantages of the invention will be described in the following description and will be partly apparent from the description or understood by the practice of the present invention. The objects and other advantages of the invention can be achieved and implemented by the structures indicated in the description, patent claims and figures. Description of the drawings [0026] The illustrated figures provide a further understanding of the invention and form part of the application. Exemplary embodiments and description thereof are used to explain the invention without unduly limiting the scope of the invention, of which:

Fig. 1 shows a structural diagram of a GPON system topology according to the prior art;

Fig. 2 shows a schematic diagram of a downlink GEM structure according to the prior art; and

Fig. 3 shows a flow chart of a data transmission method according to one embodiment of the invention.

Description of implementation examples

Brief description of the functions Embodiments of the invention provide a solution for data transmission, in which solution one type of specific information may be included in the uplink or downlink frame of the GPON system, and the specified information means nothing to all OLT / ONUs. GPON system, or the specified information is not transmitted to any GPON OLT / ONU. That is, certain information does not need to be processed by the GPT OLT / ONU. In the following embodiments, specific information is also called information that does not need to be processed by the receiver.

[0028] It should be clarified that if there is no conflict, the embodiments and features of the embodiments in the application can be combined with each other. The invention will be explained in further detail in connection with figures and drawings and embodiments.

[0029] In the following embodiments, the steps shown in the drawing figure action networks can be performed in a computer system such as a set of computer-based instructions, and although a logical order is suggested in action networks, in some circumstances, the steps shown or described can be performed in sequence other than the suggested sequence.

[0030] A method of data transmission according to an embodiment of the invention is provided. Fig. 3 is a flow chart of a data transmission method according to an embodiment of the invention. As shown in FIG. 3, the method comprises the following steps S302 to S304.

[0031] Step S302: The transmitter carries the indication information in an uplink or downlink frame transmitted to the receiver.

[0032] Step S304: The receiver discards information in the uplink frame or downlink that does not need to be processed by the receiver based on the indication information.

[0033] The method of a transmitter conveying information in an uplink or downlink frame that does not need to be processed by the receiver may include, but is not limited to, the following two methods, which two methods will be described further below.

Method I [0034] A transmitter (such as OLT) defines a specific port identifier and the port identifier in the header of the GEM frame containing specific information (i.e., information that does not need to be processed by the receiver in the GPON system) is a specific port identifier. That is, the transmitter carries information that does not need to be processed by the receiver in the GPON encapsulation frame (GEM) frame of the uplink or downlink, wherein, when the value of the port identifier in the header of the GEM frame is a predetermined value, it indicates that the GEM frame carries information that does not need to be processed by the receiver, and at this point the indication information is the port identifier in the header of the GEM frame.

Method II [0035] The OLT defines a new GEM frame data block type, the value of the data block type in the GEM frame header that contains the specific information is the value of the defined new GEM frame data block type. That is, the transmitter carries information that does not need to be processed by the receiver in a predetermined GEM frame, wherein when the value of the data block type in the frame header of the predetermined GEM frame is a predetermined value, it indicates that the GEM frame carries the information that do not need to be processed by the receiver and at the moment the indication information is the data block type in the header of the GEM frame.

[0036] After OLT / ONU receives a GEM frame containing specific information, the OLT / ONU evaluates according to one of the above two methods, whether the received GEM frame contains specific information, and then OLT / ONU rejects the GEM frame including the specified information. Especially:

in the case of the method I, the receiver judges whether the value of the port identifier in the header of the uplink frame or downlink frame is a predetermined value, and if the result of the rating is YES, discards the GEM frame whose port ID value in the frame header is in advance fixed value;

in the case of the method II, the receiver judges whether the data block type value in the header of the uplink frame or downlink frame GEM is a predetermined value, and if the result of the evaluation is YES, discards the GEM frame whose value of the data block type in the frame header is a predetermined value.

[0037] A GPON system according to an embodiment of the invention is also provided, which system comprises: a transmitter and a receiver, the receiver being an optical network unit in the case where the transmitter is the end of the optical line; or the receiver is the end of the optical line in the case where the transmitter is an optical network unit. The process in the system is the same as that in the above steps S302 to S304, as well as in the method i and method II, which will not be unnecessarily described.

[0038] The implementation process of the embodiments of the invention will be described in detail in connection with the following examples. Example i corresponds to the above method I, and example II corresponds to the above method II.

Example I [0039] In the GPON system, when the OLT / ONU does not have corresponding GEM frame contents for transmission to the ONU / OLT, the OLT / ONU may transmit part of the specific GEM frames of the downlink / uplink frames that do not need to be processed by ONU / OLT. The specified port identifier can be defined in the header of the GEM frame, and the specified port identifier is used only by OLT or ONU for transmission of a specific GEM frame (part of the data block of the specific frame does not have to be processed by the receiver), which need not be processed by ONU or OLT . When OLT / ONU transmits a part of specific GEM frames of uplink / downlink frames that do not need to be processed by ONU / OLT, the value of the port identifier in the header of the specified GEM frame is a predetermined specific port identifier.

[0040] Step 11: OLT defines a specific port identifier, the value of which is 011111111111 (it must be clarified that the value of the port identifier is only an illustration of the example and it may also be set to other values), and the specific port identifier is used only by OLT or ONU for transmitting a specific GEM frame that does not have to be processed by ONU or OLT.

[0041] Step 12: When the OLT / ONU has to transmit in the downlink / uplink frame only part of the content that does not need to be processed by the ONU / OLT, content that does not need to be processed by the ONU / OLT is encapsulated by the OLT / ONU in the data block field of the specified GEM frame, and the value of the port identifier in the header of the specified GEM frame is 011111111111.

[0042] Step 13: After receiving the GEM frame transmitted by the OLT / ONU, the ONU / OLT first performs the HEC check. If the result of the HEC check is incorrect, then the ONU / OLT rejects the GEM frame, and if the result of the HEC check is correct, then the ONU / OLT evaluates based on the value of the port identifier in the header of the GEM frame, whether the GEM frame is to be processed. If the value of the port identifier is 011111111111, then the ONU / OLT rejects the GEM frame, and if the value of the port identifier is not 011111111111, the ONU / OLT processes the received GEM frame according to the prior art method, which will not be described hereabove.

Example II [0043] In the GPON system, when the OLT / ONU has no relevant GEM frame content for transmission to the ONU / OLT, the OLT / ONU may transmit part of the specific GEM frames of the down / up link frames that need not be processed by the ONU. / OLT. The GPON system defines the specified GEM frame type, and the PTI value in the header of the specified GEM frame type is 111 (it must be clarified that 111 is only an example and the PTI value may also be other values) which indicates that the specific information carried in the data block field specified GEM frames do not have to be processed by ONU / OLT. When the PTI value is other than 111, indicates that the data information carried by the GEM frame data block field must be processed by the ONU / OLT. This will be described in detail in connection with the specific steps below.

[0044] Step 21: The GPON system defines a specific GEM frame type, and the PTI value in the header of a specific GEM frame type is 111, which indicates that the specific information carried in the data block field of the specific GEM frame does not need to be processed by the ONU / OLT. When the PTI value is other than 111, indicates that the data information carried by the GEM frame data block field must be processed by the ONU / OLT.

[0045] Step 22: When the OLT / ONU has to transmit some of the content in the downlink / uplink frames that do not have to be processed by the ONU / OLT, content that does not need to be processed by the ONU / OLT they are encapsulated in the data block field of the specified GEM frame by OLT / ONU, and the PTI value of the header of the specified GEM frame is 111.

[0046] Step 23: After receiving the GEM frame transmitted by the OLT / ONU, the ONU / OLT first performs the HEC check. If the result of the HEC check is incorrect, then the ONU / OLT rejects the GEM frame, and if the result of the HEC check is correct, then the ONU / OLT evaluates the GEM frame type based on the PTI in the GEM frame header. If the PTI value is 111, then the ONU / OLT rejects this GEM frame, and if the PTI value is a value other than 111, then the ONU / OLT processes the received GEM frame according to the prior art method, which will not be described hereily.

In this example, when the value of PTI is 111, it indicates that the specific information carried in the data block field of the specified GEM does not have to be processed by the ONU / OLT, and when the PTI value is a value other than 111, it indicates that the data information carried in the GEM frame data block field must be processed by ONU / OLT. Optionally, when the PTI is 010, 011 or 110, it indicates that the specific information carried in the data block field of the specified GEM does not have to be processed by the ONU / OLT, and when the PTI value is other than 010, 011 or 110, indicates that the data information carried in the GEM frame data block field must be processed by ONU / OLT.

[0048] In summary, by means of a method of transmitting and receiving specific information between the OLT and ONU provided in the above embodiments, the data type transmitted by the GPON system is expanded and the problem of how the transmitter and receiver of the GEM frame process when the transmitter does not have the relevant content of the GEM frame to be transmitted to the receiver is solved.

[0049] It will be appreciated by those skilled in the art that the above-mentioned modules and steps of the invention can be implemented using a general purpose computing device, can be integrated in one computing device or distributed in a network comprising a plurality of computing devices. Alternatively, the modules and steps of the invention may be implemented using the executable program code of the computing device. As a consequence, they can accordingly be stored in a storage device and executed by a computing device, or they can be included in an integrated circuit module, or many modules or their steps are contained in one integrated circuit module. In this way, the invention is not limited to any specific combination of hardware and software.