Summary of the invention
At existing problem and shortage in the above-mentioned prior art, the present invention proposes a kind of embodiments of the invention a kind of method, device and network system that transmits optical channel transmission unit by optical transfer network is provided.
A kind of method that transmits optical channel transmission unit OTU by optical transfer network OTN comprises:
At source node, the data map that the OTUj that receives and this OTN network etc. are to be sent is transmitted for the OTUk of this OTN network;
At destination node, described OTUk is separated mapping be converted to OTUj and extract the data of carrying, wherein j and k represent the speed grade of described OTU respectively.
A kind of device that sends optical channel transmission unit OTU comprises:
Strip module, the OTUj that is used for receiving peels off into ODUj;
Insert module is used for inserting among the ODUj and keeping overhead area peeling off OTUj administration overhead that the unit obtains;
Mapping block, being used for the ODUj asynchronous mapping after the insertion cell processing is optical channel data tributary units;
Multiplexing module, a plurality of optical channel data tributary units after being used for map unit handled are multiplexed into the payload area of OTUk, produce the forward error correction FEC coding of OTUk administration overhead and OTUk again, are combined into OTUk.
A kind of device that receives optical channel transmission unit OTU comprises:
Demultiplexing module is used for the payload area demultiplexing optical channel data tributary unit from OTUk;
Separate mapping block, the optical channel data tributary unit that is used for demultiplexing unit is obtained carries out the asynchronous mapping of separating, and obtains ODUj;
Extraction module is used for extracting from the reservation overhead area administration overhead of ODUj;
Composite module is used for the administration overhead that extraction unit the extracts OTUj that packs into, and produces forward error correction FEC coding, is combined into OTUj.
A kind of optical transport network system comprises:
Dispensing device, the OTUj that is used for receiving peels off into Optical Channel Data Unit-k ODUj; To keep overhead area among the administration overhead insertion ODUj among the OTUj; With described ODUj asynchronous mapping is optical channel data tributary units, and a plurality of optical channel data tributary units are multiplexed into the payload area of OTUk, and produces the forward error correction FEC coding of OTUk administration overhead and OTUk, is combined into OTUk.
Receiving system is used for the payload area demultiplexing optical channel data tributary unit from OTUk; Described optical channel data tributary unit is carried out the asynchronous mapping of separating, obtain ODUj; From the reservation overhead area of ODUj, administration overhead is extracted; With the described administration overhead OTUj that packs into, and produce forward error correction FEC coding, be combined into OTUj.
Transmit method, the Apparatus and system of information between the network that the embodiment of the invention provides, directly utilize ODUj to carry administration overhead among the source network OTUj, it is high-level inequality with transmission rate low level OTU to have solved prior art, the problem that channel qualities such as the slip that causes descend can be crossed over the more convenient OTU that transmits accurately in the optical transfer network.
Embodiment
The embodiment of the invention is applicable to the transmission process scene of OTN network system, is particularly useful for the scene of many OTN management domain intercommunication, and following examples illustrate the present invention with the example that is applied as in striding the OTN management domain.Referring to Fig. 1, the B of operator is equipped with two network B 1, B2 respectively in two places.The network that the B of operator rents the A of operator transmits passage, and the B of operator couples together network B 1, B2 by the transmission passage of renting.Administration overhead between each adjacent node among network B 1, B2, the A is kept at the overhead area that each automatic network light transmits frame.The B of operator need transmit the light of OTU among network B 1, the B2 frame overhead and transmit in the network of the A of operator for holistic management network B 1, B2.The administration overhead that present embodiment transmits frame with the light of OTU in the network B 1 is transmitted as example and describes in detail in the network of the A of operator.
How the present invention solves the described OTUj of transparent transmission in OTUk, comprises its payload part and operation/management/maintenance and disposes (OAM﹠amp; P) expense (be called for short administration overhead, also can be called the OTU administration overhead) part.
At first introduce the frame structure of OTU, as shown in table 1:
OTU frame (being applicable to all OTN speed grade such as OTUI, OTU2, OTU3) structure is 4 * 4080 block byte structure, comprise 4 * 16 row overhead area, 4 * 3808 row optical channel Payload Unit (OPUk, Optical Channel Payload unit) payload area and 4 * 256 row forward error corrections (FEC, Forward Error Correction) zone.Wherein said 4 * 16 row overhead area comprise 1 * 7 row optical channel transmission unit (OTUk) expense, 3 * 14 row Optical Channel Data Unit-k (ODUk) expenses and 4 * 2 row optical channel Payload Unit (OPUk) overhead area.Described k=1,2,3 difference correspondences 2,5G, IOG, 40G speed rank.Wherein the OTUk administration overhead is the 1st row, the 8th~14 column region, existing OTUk administration overhead comprises all purpose communication passage (GCCO of 2 bytes, Generic Communication channel) the section monitoring (SM of expense and 3 bytes, Section Monitoring) expense also comprises the reservation overhead area of 2 bytes in addition.Wherein, GCCO is used to carry the communication information between network element, and SM comprises OTUk section monitoring necessary connectedness monitoring, quality-monitoring and alarms back information such as announcement, is used for sectional management, and the administration overhead that these two parts of GCCO and SM are collectively referred to as OTUk is OAM﹠amp; P opens slightly.
Table 1OTU frame structure
The present invention need solve the OTU (OTU frame) that how to pass through another management domain of the OTN network carrying of a management domain, comprises payload part and necessary administration overhead, and described administration overhead is OAM﹠amp; P expense (comprising these two parts of GCCO and SM), described payload part are to remove OAM﹠amp in the OTU frame; Other parts beyond P expense and the FEC zone.
For convenience, the OTU frame of two different management domains is defined as OTUj and OTUk frame respectively, wherein the light of network B 1, B2 transmission frame is OTUj, and it is OTUk that the light of network A transmits frame, and the present invention need solve how to open the tip by the management of the transparent carrying of OTUk frame OTUj frame.
In order to realize that striding the OTN management domain transmits OTU, the present invention proposes a kind of method that transmits optical channel transmission unit OTU, comprising:
At source node, keep the administration overhead of the OTUj that enters the OTN network, the OTUk that described OTUj is mapped as this OTN network transmits;
At destination node described OTUk is separated mapping and be converted to OTUj and extract the administration overhead of OTUj, wherein j and k represent the speed grade of described OTU respectively, and j is less than k, and j wherein and k represent the speed grade of described OTU respectively.
Below the method that transmits optical channel transmission unit OTU by optical transfer network OTN in the embodiment of the invention is described in detail, referring to Fig. 2:
At source node, the process that the OTUj that receives is become the OTUk of this OTN comprises:
201, OTUj transmits between the network node of the B of operator, and when being sent to Node B 3, Node B 3 is sent to OTUj at the source node A1 place of the A of operator.Receive the OTUj that sends from operator B1 network at node A1.
202, frame head, frame overhead, the payload of the OTUj that receives is respectively charged into frame head district, frame overhead district, the payload section of ODUj, keep the administration overhead part in first row, 8~14 bytes in the OTUj frame simultaneously, described administration overhead is inserted into the reservation overhead area of ODUj.
203, be optical channel data tributary units with described ODUj asynchronous mapping, and a plurality of optical channel data tributary units are multiplexed into the payload area of OTUk, and the forward error correction FEC of generation OTUk administration overhead and OTUk coding, be combined into OTUk, described OTUk is gone out to see off.
At destination node, the B2 of operator received the OTUK that sends from the A of operator network A 3 nodes at B4 node place after, it is as follows that the OTUk of reception separates the concrete processing procedure that is mapped to OTUj:
204, from the payload area demultiplexing optical channel data tributary unit of the OTUk that receives, described optical channel data tributary unit is carried out the asynchronous mapping of separating, obtain ODUj.
205, from the reservation overhead area extract management expense of ODUj.
206, described administration overhead data are packed into OTUj, and produce the FEC coding, be combined into OTUj.
Transmit the method for information between the network that the embodiment of the invention provides, make OTUj and administration overhead synchronous driving, it is inequality to have solved the high-level and low level OTU1 transmission rate of prior art, and channel quality problems such as the slip that causes make OUT fall to more conveniently transmitting accurately at mid-level net.
The embodiment of the invention also provides a kind of and has transmitted the device of optical channel transmission unit OTU by optical transfer network OTN, referring to Fig. 3:
A kind of device that sends optical channel transmission unit OTU comprises:
Strip module 301, the OTUj that is used for receiving peels off into ODUj, keeps the administration overhead of the OTUj that enters the OTN network simultaneously;
Insert module 302 is used for inserting among the ODUj and keeping overhead area peeling off OTUj administration overhead that the unit obtains;
Mapping block 303, being used for the ODUj asynchronous mapping after the insertion cell processing is optical channel data tributary units,
Multiplexing module 304, a plurality of optical channel data tributary units after being used for map unit handled are multiplexed into the payload area of OTUk, produce the forward error correction FEC coding of OTUk administration overhead and OTUk again, are combined into OTUk.
A kind of device that receives optical channel transmission unit OTU comprises:
Demultiplexing module 305 is used for the payload area demultiplexing optical channel data tributary unit from OTUk;
Separate mapping block 306, the optical channel data tributary unit that is used for demultiplexing unit is obtained carries out the asynchronous mapping of separating, and obtains ODUj;
Extraction module 307 is used for extracting from the reservation overhead area administration overhead of ODUj;
Composite module 308 is used for the administration overhead that extraction unit the extracts OTUj that packs into, and produces forward error correction FEC coding, is combined into OTUj.
Transmit the device of information between the network that the embodiment of the invention provides, make OTUj and administration overhead synchronous driving, it is inequality to have solved the high-level and low level OTU1 transmission rate of prior art, and channel quality problems such as the slip that causes make OTU fall to more conveniently transmitting accurately at mid-level net.
A kind of optical transport network system that the embodiment of the invention provides comprises:
Dispensing device, the OTUj that is used for receiving peels off into Optical Channel Data Unit-k ODUj; To keep overhead area among the administration overhead insertion ODUj among the OTUj; With described ODUj asynchronous mapping is optical channel data tributary units, and a plurality of optical channel data tributary units are multiplexed into the payload area of OTUk, and produces the forward error correction FEC coding of OTUk administration overhead and OTUk, is combined into OTUk.
Receiving system is used for the payload area demultiplexing optical channel data tributary unit from OTUk; Described optical channel data tributary unit is carried out the asynchronous mapping of separating, obtain ODUj; From the reservation overhead area of ODUj, administration overhead is extracted; With the described administration overhead OTUj that packs into, and produce forward error correction FEC coding, be combined into OTUj.
The network system that the embodiment of the invention provides keeps overhead area transmission information by utilizing, and has saved the resource of system.
The above; only be the specific embodiment of the present invention, but protection scope of the present invention is not limited thereto, anyly is familiar with those skilled in the art in the technical scope that the present invention discloses; can expect easily changing or replacing, all should be encompassed within protection scope of the present invention.Therefore, protection scope of the present invention should be as the criterion by described protection range with claim.