Service scheduling method and device

Abstract

The invention discloses a service scheduling method and device, and the method comprises the steps: recognizing a deterministic service and a non-deterministic service, and dividing the deterministic service and the non-deterministic service in different time slot regions; and when the managed windowing is inserted, adjusting the windowing of the deterministic service to be before the managed windowing, so that the windowing of the deterministic service is before the managed windowing and the windowing of the non-deterministic service. According to the method and the device, service forwarding delay jitter caused by management windowing can be avoided, so that the high requirement of an industrial control scene on the certainty of a network is met.

Description

Technical Field

[0001] The present invention relates to the technical field of passive optical network, and in particular to a service scheduling method and device. Background Art

[0002] In industrial control application scenarios, there are high requirements for low latency and determinism of network forwarding. The PON system network architecture is P2MP. Different ONUs use the uplink in a time-sharing manner. In addition, the PON system also has certain management overhead. For example, in order to register a new ONU, a management time slot must be allocated. The time slot size is determined by the network coverage. During the management window, all ONUs cannot send uplink services, which causes jitter in the PON system's uplink service forwarding delay. The requirements for network determinism in industrial control scenarios cannot be met, such as Figure 3 The service numbered 2 is a deterministic service and is scheduled every 30 us. However, due to the insertion of the management window, the second scheduling of service 2 is delayed, which introduces jitter in the forwarding delay, and the jitter size is at least the size of the management window.

[0003] Therefore, how to avoid the management window being inserted before the determined service, causing delay jitter when the PON system determines the service to forward the upstream service, is a technical problem that needs to be solved urgently. Summary of the invention

[0004] The main purpose of the present invention is to provide a service scheduling method and device, which can avoid the service forwarding delay jitter caused by management windowing, thereby meeting the high requirements of industrial control scenarios on network determinism.

[0005] In a first aspect, the present application provides a service scheduling method, wherein the method comprises the steps of:

[0006] Identify deterministic services and non-deterministic services, and divide them into different time slots;

[0007] When the managed windowing is inserted, the windowing of the deterministic service is adjusted to be before the managed windowing, so that the windowing of the deterministic service is before the managed windowing and the windowing of the non-deterministic service.

[0008] In combination with the first aspect, as an optional implementation method, the OLT automatically measures the distance of the ONUs connected to it after power-on to determine the distances of the ONUs closest to and farthest from the OLT;

[0009] Determine the maximum coverage of the network based on the distance difference between the ONU closest to the OLT and the ONU farthest from the OLT.

[0010] The managed window size is set according to the maximum coverage of the network.

[0011] In combination with the first aspect, as an optional implementation method, after the ONU is powered on and registered, the OLT determines whether the currently configured managed window size meets the requirements according to the actual ranging value of the ONU;

[0012] If not, the managed window size is adjusted according to demand.

[0013] In combination with the first aspect, as an optional implementation, the deterministic service and the non-deterministic service are identified according to the protocol type of the service and the flow characteristics of the service, wherein the flow characteristics include: periodicity, byte length and duration, and rate;

[0014] Based on the different divided time slot areas, the deterministic services and the non-deterministic services are arranged in corresponding time slot areas, and the deterministic services are arranged before the non-deterministic services.

[0015] In combination with the first aspect, as an optional implementation method, based on the deterministic services and non-deterministic services identified by the ONU, the tcont type and configuration carried by each of the deterministic services and non-deterministic services are marked;

[0016] The OLT receives the tcont type and configuration sent by the ONU, and determines whether a certain service exists;

[0017] If so, the OLT adjusts the service scheduling time slot length, position and single-frame scheduling times according to demand.

[0018] In combination with the first aspect, as an optional implementation method, it is determined whether the services carried by the ONU include the deterministic services that need to be deleted;

[0019] If so, the tcont and gemport resources allocated to the service are released, and the scheduling time slot occupied by the service is released synchronously.

[0020] In a second aspect, the present application provides a partitioning module, which is used to identify deterministic services and non-deterministic services, and divide the deterministic services and non-deterministic services into different time slot areas;

[0021] The processing module is used for adjusting the windowing of the deterministic service to be before the windowing of the management when the windowing of the management is inserted, so that the windowing of the deterministic service is before the windowing of the management and the windowing of the non-deterministic service.

[0022] In combination with the first aspect, as an optional implementation, the processing module is further used for the OLT to automatically measure the distance of the ONUs connected to it after power-on, so as to determine the distances of the ONUs closest to and farthest from the OLT;

[0023] Determine the maximum coverage of the network based on the distance difference between the ONU closest to the OLT and the ONU farthest from the OLT.

[0024] The managed window size is set according to the maximum coverage of the network.

[0025] In combination with the first aspect, as an optional implementation, the processing module is further configured to, after the ONU is powered on and registered, the OLT determines whether the currently configured managed window size meets the requirements according to the actual ranging value of the ONU;

[0026] If not, the managed window size is adjusted according to demand.

[0027] In combination with the first aspect above, as an optional implementation, the division module is further used to identify deterministic services and non-deterministic services according to the protocol type of the service and the flow characteristics of the service, wherein the flow characteristics include: periodicity, byte length and duration, and rate;

[0028] Based on the different divided time slot areas, the deterministic services and the non-deterministic services are arranged in corresponding time slot areas, and the deterministic services are arranged before the non-deterministic services.

[0029] The present application provides a service scheduling method and device, wherein the method includes the steps of: identifying deterministic services and non-deterministic services, and dividing the deterministic services and non-deterministic services into different time slot areas; when the managed windowing is inserted, adjusting the windowing of the deterministic services to be before the managed windowing, so that the windowing of the deterministic services is before the managed windowing and the windowing of the non-deterministic services. The present application can avoid the service forwarding delay jitter caused by the managed windowing, thereby meeting the high requirements of the industrial control scenario for network determinism.

[0030] It is to be understood that the foregoing general description and the following detailed description are exemplary only and are not restrictive of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0032] Figure 1 A flow chart of a service scheduling method provided in an embodiment of the present application;

[0033] Figure 2 A schematic diagram of a service scheduling device provided in an embodiment of the present application;

[0034] Figure 3 A schematic diagram of a management window provided in an embodiment of the present application;

[0035] Figure 4 A schematic diagram of a deterministic service adjustment provided in an embodiment of the present application;

[0036] Figure 5 It is the ONU online flow chart provided in the embodiment of the present application;

[0037] Figure 6 A flowchart of new service time slot allocation provided in an embodiment of the present application;

[0038] Figure 7 This is a flowchart of the service deletion provided in an embodiment of the present application. DETAILED DESCRIPTION

[0039] Here, exemplary embodiments will be described in detail, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Instead, they are merely examples of devices and methods consistent with some aspects of the present invention as detailed in the appended claims.

[0040] Furthermore, the drawings are only schematic illustrations of the present disclosure and are not necessarily drawn to scale. Some of the blocks shown in the drawings are functional entities and do not necessarily correspond to physically or logically separate entities.

[0041] The embodiments of the present application are further described in detail below in conjunction with the accompanying drawings.

[0042] Reference Figure 1 , Figure 1 FIG. 1 is a flow chart of a service scheduling method provided by the present invention. Figure 1 As shown, the method comprises the steps of:

[0043] Step S101: Identify deterministic services and non-deterministic services, and divide the deterministic services and non-deterministic services into different time slot areas.

[0044] Specifically, the deterministic services and non-deterministic services are identified according to the protocol type of the services and the flow characteristics of the services, wherein the flow characteristics include: periodicity, byte length and duration, and rate;

[0045] Based on the different divided time slot areas, the deterministic services and the non-deterministic services are arranged in corresponding time slot areas, and the deterministic services are arranged before the non-deterministic services.

[0046] For easier understanding, let's take an example. In the PON system, there is a service monitoring unit (either in the OLT or in the ONU). Deterministic services are generally small bytes, small traffic, and periodic, while other services are generally random bursts. Therefore, whether it is a deterministic service can be determined by the characteristics of the traffic.

[0047] In addition, the order of deterministic and non-deterministic services can refer to Figure 4 Sorting: within the set allocation period, the deterministic services are arranged before the non-deterministic services. For example, if the allocation period is 30us, the deterministic services are arranged in the first 15us, and the non-deterministic services are arranged in the last 15us (the arrangement can be specific according to the actual situation).

[0048] In one embodiment, the OLT identifies new ONUs through the management channel, and if there are new ONUs, a standard ONU registration process is performed. It should be explained that the registration of new ONUs must be allocated a management time slot, and the time slot size is determined according to the network coverage, usually 250us. When the management window is opened, all ONUs cannot send upstream services. The management window can be understood as opening a time window to allow new ONUs to go online. In the upstream direction of the PON system, multiple ONUs send data upward at different times under the control of the OLT, but there is management information (ONU information) between the OLT and the ONU, so this information needs to take a certain time, and when the management information is transmitted, all ONUs are not allowed to send data, which is the source of jitter caused by the management window.

[0049] In one embodiment. Before identifying deterministic services and non-deterministic services, it also includes: the OLT automatically measures the distance of the ONUs hanging below after power-on to determine the distance of the ONUs closest and farthest from the OLT; according to the distance difference between the ONUs closest and farthest from the OLT (the size of the window depends on the distance difference between the nearest ONU and the farthest ONU), the maximum coverage of the network is determined; through the maximum coverage of the network, the managed window size is set (where the window size can be set smaller according to the actual application environment). When the ONU is powered on and registered, the OLT determines whether the currently configured managed window size meets the requirements based on the actual ranging value of the ONU; if not, the managed window size is adjusted according to the requirements (usually the window size is reduced).

[0050] It should be noted that, in the serial number state SN (Serial-Number-state): the OLT sends a Serial NumberRequest message to discover a new ONU and its serial number. When the OLT discovers a new ONU, it assigns an ONU-ID to the ONU, and the ONU enters the ranging state. In addition, the management window can be understood as a silent window, and the silent window is for all online ONUs not to send data, so that the new online ONU can send SN information.

[0051] Step S102: When the managed windowing is inserted, the windowing of the deterministic service is adjusted to be before the managed windowing, so that the windowing of the deterministic service is before the managed windowing and the windowing of the non-deterministic service.

[0052] Specifically, the OLT will allocate time slots and let each ONU send packets upstream according to the time slots. However, the management information is periodic and will be inserted into the process of the ONU sending data, which will preempt the time slot of the ONU sending packets. In other words, the management window will be randomly inserted before the deterministic and non-deterministic services. If it is inserted before the deterministic services, since the deterministic services have index requirements for low latency and low jitter in forwarding, jitter delay will be caused. At this time, the deterministic services after the management window will be adjusted to before the management window for data transmission (for example, if there are 4 deterministic services after the management window, then the four deterministic services will be adjusted before the management window, so that the window of the deterministic service is before the window of the management and the window of the non-deterministic service). Please refer to the processing method. Figure 4 .

[0053] If it is inserted after the deterministic service and before the non-deterministic service, and the non-deterministic service has lower requirements on jitter and latency, the managed windowing operation can be performed first.

[0054] In one embodiment. For example, there are three services ABC corresponding to three ONUs 1, 2 and 3, A is a deterministic service, B is an undeterministic service, and C is a new ONU. When scheduling service A, OLT will open a window for ONU1 to allow service A to be transmitted, and the same applies to B and C. Therefore, the windowing of deterministic services and the windowing of undetermined services refer to opening a time window to send data to OLT. In addition, it should be noted that service C cannot be ranked before service A, that is, service A has the highest ranking priority, and B and C have equal priority.

[0055] Reference Figure 2 , Figure 2 FIG. 1 is a schematic diagram of a service scheduling device provided by the present invention, such as Figure 2 As shown, the device comprises:

[0056] Division module 201: It is used to identify deterministic services and non-deterministic services, and divide the deterministic services and non-deterministic services into different time slot areas.

[0057] Processing module 202: used for adjusting the windowing of the deterministic service to be before the windowing of the management when the windowing of the management is inserted, so that the windowing of the deterministic service is before the windowing of the management and the windowing of the non-deterministic service.

[0058] Further, in a possible implementation manner, the processing module is also used for the OLT to automatically measure the distance of the ONUs connected thereto after being powered on, so as to determine the distances of the ONUs closest to and farthest from the OLT;

[0059] Determine the maximum coverage of the network based on the distance difference between the ONU closest to the OLT and the ONU farthest from the OLT.

[0060] The managed window size is set according to the maximum coverage of the network.

[0061] Further, in a possible implementation manner, the processing module is also used for, after the ONU is powered on and registered, the OLT determines whether the currently configured managed window size meets the requirement according to the actual ranging value of the ONU;

[0062] If not, the managed window size is adjusted according to demand.

[0063] Further, in a possible implementation, the partitioning module is further used to identify deterministic services and non-deterministic services according to the protocol type of the service and the flow characteristics of the service, wherein the flow characteristics include: periodicity, byte length and duration, and rate;

[0064] Based on the different divided time slot areas, the deterministic services and the non-deterministic services are arranged in corresponding time slot areas, and the deterministic services are arranged before the non-deterministic services.

[0065] Further, in a possible implementation manner, the processing module is further used to mark the tcont type and configuration carried by each of the deterministic service and the non-deterministic service based on the deterministic service and the non-deterministic service identified by the ONU;

[0066] The OLT receives the tcont type and configuration sent by the ONU, and determines whether a certain service exists;

[0067] If so, the OLT adjusts the service scheduling time slot length, position and single-frame scheduling times according to demand.

[0068] Further, in a possible implementation manner, the processing module is further used to determine whether the services carried by the ONU include the deterministic services that need to be deleted;

[0069] If so, the tcont and gemport resources allocated to the service are released, and the scheduling time slot occupied by the service is released synchronously.

[0070] Reference Figure 3 , Figure 3 The window diagram of the management provided by the present invention is shown as follows: Figure 3 As shown:

[0071] The registration of ONU must allocate management time slots. The time slot size is determined by the network coverage, usually 250us. When the management window is opened, all ONUs cannot send upstream services, which causes jitter in the upstream service forwarding delay of the PON system, and cannot meet the requirements of industrial control scenarios for network determinism, such as Figure 3 : The service numbered 2 is a deterministic service and is scheduled every 30us. However, due to the insertion of the management window, the second scheduling of service 2 is delayed, which introduces jitter in the forwarding delay. The jitter size is at least the size of the management window.

[0072] Reference Figure 4 , Figure 4 The following is a qualitative service adjustment example provided by the present invention. Figure 4 As shown:

[0073] Based on the set allocation cycle, the deterministic services and non-deterministic services are sorted, that is, the deterministic services are arranged before the non-deterministic services. The dotted lines 1 and 2 in the figure are deterministic services, which are implemented as non-deterministic services. Figure 3 If the management window is opened before the deterministic service, the deterministic service will be adjusted forward to ensure that the management window is opened after the deterministic service window. That is, the services numbered 1 and 2 are deterministic services, which are scheduled every 30us to ensure that the management window is opened after the deterministic service window, avoiding the introduction of jitter to the forwarding delay of the deterministic service.

[0074] Reference Figure 5 , Figure 5 The figure shows the ONU online flow chart provided by the present invention, as shown in FIG. Figure 5 As shown:

[0075] The system pre-configures the window size templates for management according to different ONU distance values, such as 1KM, 2KM, 5KM, 10KM, and 20KM. The system's window size configuration needs to meet the maximum ONU distance in this PON network. After the ONU is powered on and registered, the OLT determines whether the currently configured management window size meets the requirements based on the ONU distance value. If not, it is adjusted according to the pre-configured template. Among them, a PON interface sets a window size template according to the farthest distance of the downstream ONU. By default, a template with a maximum distance can be configured to ensure that all ONUs can register normally. After the ONU completes registration, the template can be adjusted according to the actual distance measurement. In general, the coverage range is relatively small in industrial environments, so the window size can be reduced according to actual conditions.

[0076] Specifically, after being powered on, the OLT automatically measures the distance of the downstream ONUs to determine the distances of the nearest and farthest ONUs from the OLT, and then determines the network coverage range. The size of the managed window can be set according to the coverage range to accurately identify the managed window position. It is understandable that by default, the size of the OLT window supports a coverage range of 20km, so the managed window is relatively large, but such a large coverage range is not required in industrial scenarios, so the window size needs to be adjusted according to the actual range. The smaller the managed window, the easier it is for the OLT to determine the location of the managed window, and the smaller the impact on network jitter.

[0077] Reference Figure 6 , Figure 6 The flowchart of the new service time slot allocation provided by the present invention is shown as follows: Figure 6 As shown:

[0078] Based on the deterministic and non-deterministic services identified by the ONU, the tcont type and configuration carried by each of the deterministic and non-deterministic services are marked (Tcont is the unit for carrying services in the PON system, and the mark is used to mark the service carried by the tcont as a deterministic service); the OLT receives the tcont type and configuration sent by the ONU, and determines whether there is a deterministic service; if so, the OLT adjusts the service scheduling time slot length, position and single-frame scheduling times according to demand.

[0079] Specifically, after the ONU goes online, the system configures services, and only needs to perform new configuration of conventional services. When the ONU is initially configured online, all services are conventional best-effort services. During the service operation, the ONU identifies and determines the type of service by itself, mainly through the protocol type of the service (such as Modbus, Profinet, EtherCAT, CAN, CC-link, etc.), and the flow characteristics of the service (such as periodicity, byte length, duration, rate, etc.). After determining the service type, the ONU will carry the tcont corresponding to the service, and the relevant service parameters (service type, required bandwidth, delay characteristics, etc.) are packaged and reported to the OLT through the management channel. The OLT adjusts the service scheduling time slot as required, and configures the length of the time slot, the number of single-frame scheduling, and the scheduling position within the 125us scheduling cycle as required (the time slot of each service is allocated by the OLT, so after identifying the deterministic service, the OLT can adjust the position of the time slot allocated to the deterministic service to ensure that it is not interfered with by the windowing of management and the windowing of non-deterministic services).

[0080] Reference Figure 7 , Figure 7 The flowchart of service deletion provided by the present invention is shown as follows: Figure 7 As shown:

[0081] For deterministic services that need to be deleted, the service deletion action occurs when the service is manually deleted or the ONU is manually authorized. When deleting, first determine whether the services carried by the ONU include deterministic services. If they are included, only the tcont and gemport resources allocated to the carried services are released, and the deterministic scheduling time slots occupied by the service must also be released synchronously.

[0082] The above description is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest range consistent with the principles and novel features applied for herein.

Claims

1. A service scheduling method, characterized in that: include: Identify deterministic services and non-deterministic services, and divide them into different time slots; When the managed windowing is inserted, the windowing of the deterministic service is adjusted to be before the managed windowing, so that the windowing of the deterministic service is before the managed windowing and the windowing of the non-deterministic service.

2. The method according to claim 1, characterized in that Before the identifying of the deterministic business and the non-deterministic business, the method further includes: After being powered on, the OLT automatically measures the distance of the ONUs connected to it to determine the distances of the ONUs closest to and farthest from the OLT. Determine the maximum coverage of the network based on the distance difference between the ONU closest to the OLT and the ONU farthest from the OLT. The managed window size is set according to the maximum coverage of the network.

3. The method according to claim 2, characterized in that Also includes: When the ONU is powered on and registered, the OLT determines whether the currently configured managed window size meets the requirements based on the actual ranging value of the ONU; If not, the managed window size is adjusted according to demand.

4. The method according to claim 1, characterized in that: The identifying of the deterministic service and the non-deterministic service and dividing the deterministic service and the non-deterministic service into different time slot areas includes: Identify deterministic services and non-deterministic services according to the protocol type of the service and the flow characteristics of the service, wherein the flow characteristics include: periodicity, byte length and duration, and rate; Based on the different divided time slot areas, the deterministic services and the non-deterministic services are arranged in corresponding time slot areas, and the deterministic services are arranged before the non-deterministic services.

5. The method according to claim 1, characterized in that Also includes: Based on the deterministic services and non-deterministic services identified by the ONU, mark the tcont types and configurations carried by the deterministic services and non-deterministic services respectively; The OLT receives the type and configuration of tcont sent by the ONU, and determines whether a certain service exists; If so, the OLT adjusts the service scheduling time slot length, position and single-frame scheduling times according to demand.

6. The method according to claim 5, characterized in that It also includes the deletion process of deterministic services, which includes: Determine whether the services carried by the ONU include the deterministic services that need to be deleted; If so, the tcont and gemport resources allocated to the service are released, and the scheduling time slot occupied by the service is released synchronously.

7. A service scheduling device for implementing the service scheduling method according to any one of claims 1 to 6, characterized in that: include: A division module, which is used to identify deterministic services and non-deterministic services, and divide the deterministic services and non-deterministic services into different time slot areas; The processing module is used for adjusting the windowing of the deterministic service to be before the windowing of the management when the windowing of the management is inserted, so that the windowing of the deterministic service is before the windowing of the management and the windowing of the non-deterministic service.

8. The device according to claim 7, characterized in that: The processing module is also used for the OLT to automatically measure the distance of the ONUs connected to it after it is powered on, so as to determine the distances of the ONUs closest to and farthest from the OLT; Determine the maximum coverage of the network based on the distance difference between the ONU closest to the OLT and the ONU farthest from the OLT. The managed window size is set according to the maximum coverage of the network.

9. The device according to claim 8, characterized in that: The processing module is also used for, after the ONU is powered on and registered, the OLT determines whether the currently configured managed window size meets the requirements according to the actual ranging value of the ONU; If not, the managed window size is adjusted according to demand.

10. The device according to claim 7, characterized in that: The division module is further used to identify deterministic services and non-deterministic services according to the protocol type of the service and the flow characteristics of the service, wherein the flow characteristics include: periodicity, byte length and duration, and rate; Based on the different divided time slot areas, the deterministic services and the non-deterministic services are arranged in corresponding time slot areas, and the deterministic services are arranged before the non-deterministic services.

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