WO2011140873A1

WO2011140873A1 - Data transport method and apparatus for optical transport layer

Info

Publication number: WO2011140873A1
Application number: PCT/CN2011/072550
Authority: WO
Inventors: 刘冠葳; 刘新菊; 钱方正; 姜维
Original assignee: 中兴通讯股份有限公司
Priority date: 2010-05-14
Filing date: 2011-04-08
Publication date: 2011-11-17
Also published as: CN101854567B; CN101854567A

Abstract

The invention discloses a data transport method and an apparatus for an optical transport layer. The method includes: setting available channels on the line side of the optical transport layer into an aggregation group (S202), and through the above mentioned available channels of the aggregation group, transporting service data on the client side between a layer 2 switch unit and an optical transport network (S204). The invention enables sufficient utilization of all channels of each wavelength on the line side, and enables protection on Ethernet services of all channels on the line side.

Description

TECHNICAL FIELD The present invention relates to the field of communications, and in particular to a data transmission method and apparatus for an optical transmission layer. BACKGROUND OF THE INVENTION Currently, in a Dense Wavelength Division Multiplex (DWDM) system, for an optical transmission layer of a primary network, a line side channel is mainly protected by 1+1, 1 : 1 or 1: N. Ways to improve the reliability of the link.

The 1+1 protection mode means that the same information (concurrent) is sent on both the active and standby channels, and the receiving end selects to receive the service on the active channel under normal conditions. Since the services on the active and standby channels are the same, when the primary channel is damaged, the active service can be restored by switching to select the service on the standby channel.

1 : 1 protection mode means that the sender sends the primary service on the primary channel and sends the extra service (low-level service) on the alternate channel. The receiver receives the primary service from the primary channel and receives the primary service from the secondary channel. Additional business. When the primary channel is damaged, in order to ensure the transmission of the primary service, the transmitting end switches the primary service to the alternate channel for transmission, and the receiving end switches to select the primary service from the alternate channel. At this time, the additional service is terminated, and the primary service is terminated. The service transmission is restored;

1 : N protection mode means that N service channels share a protection channel. When one of the N service channels fails, the service on the service channel is switched to the alternate channel for transmission. If multiple service channels in the N service channels are faulty, the protection of multiple services cannot be implemented. Similarly, M: N protection means that N service channels share M protection channels. The inventor has found that, in the above several protection modes, when the service channel is normal, the protection channel does not transmit the service, or transmits the same service as the service channel, or transmits additional services, and each service channel is independent of each other, thereby causing The bandwidth utilization of the line side channel is not high, and the channel bandwidth reusability is not strong. Moreover, these protection modes cannot protect all line side service channels. SUMMARY OF THE INVENTION A primary object of the present invention is to provide a data transmission method and apparatus for an optical transmission layer to solve at least one of the above problems. According to an aspect of the present invention, a data transmission method for an optical transmission layer is provided, including: setting an available channel on a line side of an optical transmission layer in an aggregation group; between a layer 2 switching unit and an optical transmission network, The customer side service data is transmitted through the available channels in the above aggregation group. The available channel on the line side is a transmission channel between a layer 2 switch port and an optical transport network OTN transmission unit on the layer 2 switching unit, and an OTN between the OTN transmission unit and the optical transport network. Layer channel composition. The setting of the available channel on the line side of the optical transmission layer to the aggregation group includes: the layer 2 switching unit configuring the aggregation group for the channel on the line side; and the layer 2 switching unit polling the line side Alarm information of each of the OTN layer channels and state information of a transmission channel between each of the Layer 2 switch ports and the OTN transmission unit; the Layer 2 switching unit is in a connected state with a transmission channel between the OTN transmission unit, The Layer 2 switch port with no alarm information on the corresponding OTN layer channel is bound to the aggregation group. The Layer 2 switching unit is configured to be in the connection state with the transmission channel of the OTN transmission unit, and the Layer 2 switching port of the corresponding OTN layer channel without the alarm information is bound to the aggregation group. Whether the OTN layer channel corresponding to the Layer 2 switching port has alarm information generated, and if not, further determining whether the transmission channel between the Layer 2 switching port and the OTN transmission unit is in a connected state, and if so, and If the layer switch port is not bound to the aggregation group, the layer 2 switch port is bound to the channel. If it is determined that the OTN layer channel has the alarm information generated, the method further includes: setting the state of the Layer 2 switching port to a non-forwarding state, and determining whether the Layer 2 switching port corresponding to the OTN layer is bound The aggregation group is determined, and if yes, the Layer 2 switch port is deleted from the aggregation group. If it is determined that the transmission channel between the Layer 2 switch port and the OTN transmission unit is not in the connection state, the method further includes: setting a state of the Layer 2 switch port to a non-forward state, and determining that the OTN layer corresponds to Whether the Layer 2 switching port is bound to the aggregation group, and if yes, deleting the Layer 2 switching port from the aggregation group. The transmitting the service data of the client side by using the available channel in the aggregation group includes: the layer 2 switching unit receiving service data from the client side; and the layer 2 switching unit passing one or more of the aggregation groups The Layer 2 switching port forwards the service data to the OTN chip; the OTN chip sends the service data to the optical transport network through an OTN layer channel between the OTN chip and the optical transport network. According to another aspect of the present invention, a layer 2 switching unit is provided, including: an aggregation management module and a transmission module. The aggregation management module is configured to set an available channel on the line side of the optical transport layer as an aggregation group, where the available channel is a transmission channel between the Layer 2 switch port and the OTN transmission unit on the Layer 2 switching unit, and the OTN. The OTN layer channel is formed between the transmission unit and the optical transport network; and the transmission module is configured to transmit the service data of the client side between the layer 2 switching unit and the optical transport network through the available channels in the aggregation group. The layer 2 switching unit further includes: a main control module, configured to configure the aggregation group; and a detection module, configured to poll the alarm information of each of the OTN layer channels, and each of the Layer 2 switch ports and the OTN transmission unit Status information of the transmission channel between the two; the aggregation management module is configured to bind the transmission channel of the OTN transmission unit to the connection state, and the corresponding OTN layer channel has no alarm information binding layer 2 switch port to the aggregation group. The main control module is further configured to set the corresponding OTN layer channel with alarm information or a Layer 2 switch port that is not in a connection state with the OTN transmission unit to be in a non-forward state; the aggregation management module further The layer 2 switch port that is configured to have alarm information in the corresponding OTN layer channel in the aggregation group or is not connected to the transmission channel between the OTN transmission unit is deleted from the aggregation group. According to the present invention, by setting the available channels on the line side of the optical transport layer in an aggregation group, and transmitting the service data of the client side between the layer 2 switching unit and the optical transport network through the available channels in the aggregation group, the solution is solved. In the related art, the bandwidth utilization of the line side channel is not high, and the reusability is not strong, and the wavelength channels on all line sides are fully utilized, and the Ethernet services of all line side channels can be protected. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are set to illustrate,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, In the drawing: 1 is a schematic structural diagram of a DWDM system according to an embodiment of the present invention; FIG. 2 is a flowchart of a data transmission method of an optical transmission layer according to Embodiment 1 of the present invention; FIG. 3 is a line side channel link according to an embodiment of the present invention; FIG. 4 is a schematic structural diagram of a two-layer switching unit according to Embodiment 2 of the present invention; FIG. 5 is a schematic structural diagram of a two-layer switching unit according to Embodiment 2 of the present invention; FIG. 6 is a schematic diagram of optical transmission according to Embodiment 2 of the present invention; A flowchart of a data transmission method of a layer; FIG. 7 is a flowchart of determining whether to bind a layer 2 switch port to an aggregation group of switch chip hardware according to the second embodiment of the present invention. BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. It should be noted that the embodiments in the present application and the features in the embodiments may be combined with each other without conflict. 1 is a schematic structural diagram of a DWDM system according to an embodiment of the present invention. As shown in FIG. 1, in the embodiment of the present invention, a client-side service is accessed through a Layer 2 switching unit 1, and a client-side service is accessed through a Layer 2 switching unit 1. The transmission to the optical transport network 2 (i.e., the DWDM system), in the embodiment of the present invention, the side accessing the DWDM system or the optical transport network 2 is referred to as the line side. Link aggregation is to aggregate multiple physical Ethernet ports to form a logical aggregation group. The upper layer entities in the same aggregation group use multiple physical links in the same aggregation group as one logical link. Link aggregation can implement load balancing between the member ports of an aggregation group to increase the bandwidth. At the same time, each member port of the same aggregation group is dynamically backed up with each other, so the reliability of the connection can be improved. As shown in FIG. 1, in the embodiment of the present invention, the available channel between the layer 2 switching unit 1 and the optical transport network 2 (ie, the line side) is set as an aggregation group. If all the channels on the line side are normal, all the line side channels in the same aggregation group can transmit services on any client side. When there are roadblocks on the line side, the customer side services can be transmitted through other channels of the aggregation group. Therefore, in the embodiment of the present invention, the service group controls the service transmission, and the protection of all channel services can be realized without other protection switching protocols, and the bandwidth can be increased without using other aggregation devices, and the bandwidth of the channel is fully utilized. Reduce network construction and equipment maintenance costs. The data transmission method and the layer 2 switching unit of the optical transmission layer provided by the embodiment of the present invention are described below with reference to FIG. Embodiment 1 FIG. 2 is a flowchart of a data transmission method of an optical transmission layer in the embodiment, where the method mainly includes the following steps (step S202 - step S204): Step S202, setting an available channel on the line side of the optical transmission layer at In an aggregation group; in practical applications, as shown in FIG. 3, the channel on the line side is transmitted between the Layer 2 switching port on the Layer 2 switching unit and the Optical Transmit Net (OTN) transmission unit. The channel and the OTN layer channel connection between the OTN transmission unit and the optical transport network are formed. When the aggregation group is set, the line side port can be configured in the same aggregation group according to the transmission quality of the line side channel. The transmission quality of the line side channel can pass the alarm of the OTN layer channel between the OTN transmission unit and the optical transmission network. The information and the status information of the transmission channel between the Layer 2 switching port and the OTN transmission unit in the Layer 2 switching unit are jointly indicated, for example, if the OTN layer channel between the OTN transmission unit and the optical transport network has no alarm information and the OTN If the status of the transmission channel between the transmission unit and the Layer 2 switch port is the connection state, the line side channel is regarded as an available channel, and the Layer 2 switch port is bound to the aggregation group. In a preferred embodiment of the present invention, the layer 2 switching unit can acquire the alarm information of each channel OTN layer (that is, the OTN layer channel between the OTN transmission unit and the optical transport network) and the OTN transmission unit and the second in a polling manner. Status information of the transmission channel between the layer switch ports. If the OTN layer does not have the alarm information, the status information of the transmission channel between the OTN transmission unit and the Layer 2 switch port is further obtained, if the status information indicates that the transmission channel between the OTN transmission unit and the Layer 2 switch port is currently located. In the connection state, the Layer 2 switch port is bound to the aggregation group. Otherwise, to prevent the Layer 2 switch port from being in the aggregation group, the Layer 2 switch port can be set to not forward. If the Layer 2 switch port is bound to the aggregation group, the Layer 2 switch port is removed from the aggregation group. And if the OTN layer channel corresponding to the layer 2 switch port has the alarm information, the layer 2 switch port can be set to the non-forward state, and if the layer 2 switch port is bound to the aggregation group, The Layer 2 switch port is removed from the aggregation group. Step S204: The service data of the client side is transmitted between the layer 2 switching unit and the optical transport network through the available channels in the aggregation group. For example, when the Layer 2 switching unit receives the service data from the client side, the Layer 2 switching unit may send the service data to the transmission unit through one or more Layer 2 switching ports in the aggregation group, and the transmission unit performs the service. The data is converted and sent to the optical transport network. In the related art, the line side channel mainly uses a transmission mode of 1+1, 1:1, or 1: ,, and each service channel is independent of each other, thereby causing problems such as low bandwidth utilization of the line side channel, and in this embodiment, According to the transmission quality of the line side channel, the line side port is configured in the same aggregation group, and the aggregation group controls the service transmission, and all the channel services can be protected without other protection switching protocols, and bandwidth can be realized without other aggregation devices. Increase, make full use of the various wavelength channels on the line side, reducing the cost of network establishment and equipment maintenance. In the actual application, the foregoing method of the present embodiment can be implemented by extending the existing Layer 2 switching unit. FIG. 4 is a schematic structural diagram of a Layer 2 switching unit according to the embodiment. The Layer 2 switching unit mainly includes: Management module 40 and transmission module 42. The aggregation management module 40 is configured to set an available channel on the line side of the optical transport layer as an aggregation group, where the available channel is a transmission channel between the layer 2 switch port and the buffer transmission unit on the layer 2 switch unit, and ΟΤΝ forming a layered channel between the transmission unit and the optical transport network; the transmission module 42 is configured to transmit the service data of the client side between the layer 2 switching unit and the optical transport network through one or more available channels in the foregoing aggregation group . The above-mentioned Layer 2 switching unit of the present embodiment can improve the utilization of the line side channel by setting the available channel on the line side as an aggregation group and transmitting the traffic on any client side through one or more available channels in the aggregation group. Rate and reliability of the line side link. Embodiment 2 FIG. 5 is a schematic structural diagram of a Layer 2 switching unit according to the embodiment. In this embodiment, the Layer 2 switching unit further includes: a main control module 44 and a detection module 46. The main control module 44 is configured to configure the foregoing aggregation group. The detection module 46 is configured to poll the alarm information of each layer channel and the status information of the transmission channel between each layer 2 switch port and the transmission unit. The module 40 is configured to bind the layer 2 switch port with the transmission channel between the transmission channel and the transmission channel, and the corresponding layer 2 channel has no alarm information to the aggregation group configured by the main control module 44. In a preferred embodiment of the present invention, the main control module 44 is further configured to set the corresponding layer channel with alarm information or a layer 2 switch port that is not in a connection state with the transmission channel to be in a non-forward state; The aggregation management module 40 is further configured to correspond to the foregoing aggregation group. The OTN layer channel has the alarm information or the Layer 2 switching port that is not connected to the transmission channel between the OTN transmission unit and is deleted from the aggregation group. With the Layer 2 switching unit of the present embodiment, the aggregation group can be set in the state of the Layer 2 switching port and the corresponding OTN layer channel alarm information, and the corresponding OTN layer channel has alarm information or Layer 2 that is not in the connected state. The switch port is set to the non-forward state, thereby avoiding the case where the line side channel is looped. FIG. 6 is a flowchart of the data transmission method of the optical transmission layer in the embodiment, which mainly includes the following steps: Step 601: The main control module 44 sets the Layer 2 switching port connected to the OTN transmission unit as an aggregation group. The aggregation group at this time is only the aggregation group definition of the software layer. The aggregation group port that is actually bound to the switch chip hardware needs subsequent step selection. As shown in FIG. 3, the Layer 2 switch port and the OTN layer channel are corresponding to each other. Therefore, setting the Layer 2 switch port as an aggregation group is equivalent to setting the line side OTN channel as an aggregation group. Step 602: The detection module 46 polls the alarm state of each OTN layer channel on the line side and the connection state of the layer 2 switch port, and sends the alarm information of each OTN layer channel and the connection state of the layer 2 switch port to the aggregation management module 40. Step 603: The aggregation management module 40 determines whether to bind the Layer 2 switch port to the aggregation group of the switch chip hardware according to the alarm and port connection status of the OTN layer channel, and the specific process is shown in FIG. 7; Step 604, when the OTN layer channel and When the connection status of the Layer 2 switching port is normal, the line side channel is set to an aggregation group by the above steps. The Ethernet packets on the client side are forwarded to the Layer 2 switching port through the Layer 2 switching unit. The Layer 2 switching ports on the line side are all in the same aggregation group. It is sent to the OTN transmission unit through the aggregation port. The OTN transmission unit encapsulates the Ethernet 4 into an OTN frame and transmits it to the optical transport network through channels of different wavelengths. Step 605: When the link status of an OTN layer channel or a Layer 2 switch port on the line side fails, the Ethernet side of the client side can be transmitted to the optical transmission network through any one of the wavelength channels in the aggregation group. In practical applications, the probability of failure of all line side channels is very low. Therefore, the optical transmission layer data transmission method provided by the embodiment of the present invention has high reliability. 7 is a flowchart of determining whether to bind a Layer 2 switch port to an aggregation group of the switch chip hardware in the embodiment, and the method includes the following steps: Step 701: Acquire an alarm of a current OTN layer channel; for example, the detection module 46 The alarm state of the OTN layer is obtained from the OTN transmission unit, and then transmitted to the aggregation management module 40 for processing. Step 702: Determine whether there is an alarm generated in the OTN layer of the channel. If yes, go to step 703; otherwise, go to step 705. The aggregation management module 40 processes the alarm information sent by the detection module 46 according to the alarm priority order of the OTN layer. One of the listed alarms is considered to have an alarm generated, and the priority of detecting the alarm is from top to bottom. Table 1.

Step 703: Determine whether the Layer 2 switch port connected to the channel is configured in the aggregation group of the chip. If yes, go to step 707; otherwise, go to step 704; Step 704: Set the Layer 2 switch port to not forward. By configuring the switch chip, you can control the port to not participate in the exchange and forwarding of packets. This operation is to prevent the line side ringing when the line side port is not in the aggregation group. Step 705: Obtain a connection state of the Layer 2 switch port connected to the channel. The alarm priority of the OTN layer is higher than the link state alarm priority of the switch chip port, and the OTN layer alarm belongs to the external alarm of the device. The link alarm is an internal alarm of the device. Therefore, in this embodiment, the alarm of the OTN layer is preferentially acquired and processed, of course, vice versa. Step 706: Determine whether the transmission channel of the Layer 2 switch port and the OTN chip is in a connected state. If yes, go to step 708; otherwise, go to step 707; Step 707, Step 704, set the Layer 2 switch port to not forward. Step 708: Determine whether the Layer 2 switch port is bound to the hardware aggregation group of the switch chip, and if yes, perform step 4 712; otherwise, perform step 4 710; Step 709, perform the Layer 2 switch port The eNB is removed from the hardware aggregation group. Step 710: Bind the Layer 2 switch port to the switch chip hardware aggregation group. Step 711: Set the Layer 2 switch port to the forwarding state. Yan Wen. Step 4 gathers 712 and goes to the next line side port for processing. The line side channel link aggregation can be completed through the above steps. It should be noted that although the aggregation group is set on the layer 2 switching unit side as an example in the foregoing embodiment, the present invention is not limited thereto. In practical applications, the optical transport network may also set the client side channel in a similar manner. The aggregation group, the specific implementation is not mentioned. From the above description, it can be seen that the line-side wavelength channel can be protected by the embodiment of the present invention, and the protection mode provided by the embodiment of the present invention is relative to the protection mode of 1+1, 1 : 1 or 1: N. More reliable. Moreover, the technical solution provided by the embodiment of the present invention can also improve the utilization of the line side channel bandwidth. Obviously, those skilled in the art should understand that the above modules or steps of the present invention can be implemented by a general-purpose computing device, which can be concentrated on a single computing device or distributed over a network composed of multiple computing devices. Alternatively, they may be executed by a computing device The program code is implemented so that they can be stored in the storage device by the computing device, and in some cases, the steps shown or described can be performed in a different order than here, or they can be separately produced. The individual integrated circuit modules are implemented, or a plurality of modules or steps thereof are fabricated into a single integrated circuit module. Thus, the invention is not limited to any specific combination of hardware and software. The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes can be made to the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the scope of the present invention are intended to be included within the scope of the present invention.

Claims

Claim

A data transmission method for an optical transmission layer, comprising:

The available channels on the line side of the optical transport layer are set in an aggregation group; between the Layer 2 switching unit and the optical transport network, the service data of the client side is transmitted through the available channels in the aggregation group.

2. The method according to claim 1, wherein the available channel on the line side is transmitted between a layer 2 switch port on the layer 2 switching unit and an optical transport network OTN transmission unit.

3. The method according to claim 2, wherein setting the available channels on the line side of the optical transport layer to the aggregation group comprises:

The Layer 2 switching unit configures the aggregation group for the channel on the line side; the Layer 2 switching unit polls the alarm information of each OTN layer channel on the line side and each of the Layer 2 switch ports and Status information of a transmission channel between OTN transmission units;

The Layer 2 switching unit binds the Layer 2 switching port that is in the connected state with the transmission channel of the OTN transmission unit, and the corresponding OTN layer channel has no alarm information, and is bound to the aggregation group.

4. The method according to claim 3, wherein the Layer 2 switching unit is to be connected to a Layer 2 switching port in which the transmission channel between the OTN transmission unit is in a connected state and the corresponding OTN layer channel has no alarm information. The aggregation group is determined to include:

The layer 2 switching unit determines whether the OTN layer channel corresponding to the layer 2 switch port has alarm information generated. If no alarm information is generated, further determining whether the transmission channel between the layer 2 switch port and the OTN transmission unit is If the connection is in the connected state, and the Layer 2 switch port is not bound to the aggregation group, binding the Layer 2 switch port to the channel is available.

The method according to claim 4, wherein, if it is determined that the OTN layer channel has alarm information generated, the method further includes: setting a state of the layer 2 switch port to a non-forwarding state, And determining, by the OTN layer, that the Layer 2 switch port is bound to the aggregation group, and if yes, deleting the Layer 2 switch port from the aggregation group.

The method according to claim 4, wherein if it is determined that the transmission channel between the Layer 2 switch port and the OTN transmission unit is not in the connected state, the method further includes: setting a state of the Layer 2 switch port to The state of the layer is not forwarded, and it is determined whether the layer 2 switch port corresponding to the OTN layer is bound to the aggregation group. If yes, the layer 2 switch port is deleted from the aggregation group.

The method according to any one of claims 3 to 6, wherein transmitting the service data of the client side through the available channels in the aggregation group comprises:

The layer 2 switching unit receives service data from a client side;

The Layer 2 switching unit forwards the service data to the OTN chip through one or more Layer 2 switch ports in the aggregation group; the OTN chip passes between the optical transport network and the optical transport network The OTN layer channel transmits the service data to the optical transport network.

8. A Layer 2 switching unit, comprising:

The aggregation management module is configured to set an available channel on the line side of the optical transport layer as an aggregation group, where the available channel is a transmission channel between the layer 2 switch port and the OTN transmission unit on the layer 2 switch unit, and Between the OTN transmission unit and the OTN layer channel between the optical transport network;

The transmission module is configured to transmit the service data of the client side between the layer 2 switching unit and the optical transport network through an available channel in the aggregation group.

9. The layer 2 switching unit according to claim 8, further comprising:

a main control module, configured to configure the aggregation group;

a detection module, configured to poll the alarm information of each of the OTN layer channels and status information of a transmission channel between each of the Layer 2 switch ports and the OTN transmission unit; the aggregation management module is configured to be connected to the OTN transmission unit A Layer 2 switching port in which the transmission channel is in the connected state and the corresponding OTN layer channel has no alarm information is bound to the aggregation group.

10. The layer 2 switching unit according to claim 9, wherein The main control module is further configured to set the corresponding OTN layer channel with alarm information or a Layer 2 switch port that is not in a connection state with the OTN transmission unit to be in a non-forwarding state;

The aggregation management module is further configured to delete, from the aggregation group, a layer 2 switch port in which the corresponding OTN layer channel in the aggregation group has alarm information or is not connected to the transmission channel between the OTN transmission units.