METHOD FOR DETERMINING A NETWORK PARTICIPANT'S CHAIN ​​POSITION

Abstract

The invention relates to a method for determining a chain position of a network subscriber (21.1-21.4) in an Ethernet network, in which the network subscribers (21.1-21.4) are connected to one another in a daisy chain and the daisy chain is coupled, at its two ends, to a respective port (11a-16a, 11b-16b) of an Ethernet gateway (1). The method comprises the following steps: (a) deactivating one of the two ports (11a-16a, 11b-16b) of the Ethernet gateway (1); (b) acquiring a status message from one of the network subscribers (21.1-21.4) concerning non-connected ports (22.1a-22.4a, 22.1b-22.4b) of the network subscriber (21.1-21.4) in question; (c) extracting at least one identification number from the status message from the network subscriber (21.1-21.4) in question and assigning a first chain position to the identification number; (d) deactivating the other port (22.1a-22.4a, 22.1b-22.4b) of the network subscriber (21.1-21.4) in question; and (e) repeating steps (b) to (d) until all of the network subscribers (21.1-21.4) with their identification number have been acquired, wherein subsequent chain positions are assigned in the repetitions of step (c). The invention furthermore relates to an arrangement of agricultural devices, in particular milking stalls, which are designed to carry out the method.

Description

[0001] Method for determining a chain position of a network participant

[0002] The invention relates to a method for determining the chain position of a network participant in an Ethernet network, in which the network participants are connected to one another in a daisy chain, and the daisy chain is coupled at both ends to a port of an Ethernet gateway. The invention further relates to an arrangement of agricultural equipment with network participants that is suitable for implementing the method.

[0003] Traditionally, Ethernet networks often use a star topology, in which a number of network nodes are connected in a star configuration, each connected to a gateway port. In this topology, it is easy to query the identifiers of the network nodes—for example, their assigned IP (Internet Protocol) address or their inherently assigned MAC (Media Access Control) address and the port to which the network node is connected. Such a query is relevant, for example, when a large number of similar network nodes are located in a system.

[0004] Agricultural facilities, such as milking parlors, often have such a large number of initially similar network participants.

[0005] An example of a milking parlor is a rotary milking parlor, which can contain a large number of similar milking stalls arranged along the circumference of the rotary milking parlor. Their control devices are equipped with an Ethernet connection for monitoring and / or control. Each stall is assigned a stall number. If the assignment between the stall number and the gateway port in a star topology is known from a wiring diagram, an identification number, such as the IP address and / or MAC address, can be easily determined for each stall.

[0006] In addition to the star topology, a daisy chain topology is now also used in Ethernet networks. Suitable network nodes have two Ethernet ports, which connect them to their neighbors or, at the end of the chain, to a gateway port. The resulting ring structure offers the advantages of potentially simpler cabling between network nodes and also a certain degree of redundancy, since at least an interruption in a connection can be compensated for by allowing the network nodes to be reached from different sides.

[0007] The daisy chain topology can also be used in agricultural facilities, for example the previously described milking carousel or other milking parlors, i.e. arrangements of milking places, in particular to reduce the wiring effort.

[0008] Even with a daisy chain topology, a list of network nodes' identification numbers, such as a list of IP addresses and / or MAC addresses, can be easily recorded. However, no information is available about which network node is located at which position within the daisy chain. Accordingly, a simple mapping between slot numbers on the milking carousel and identification numbers can no longer be established.

[0009] Instead, during installation, an identification number of the network device must be read locally on the device or determined via a directly connected service computer, and the identification number must then be assigned to the location number in an assignment table. This process could be simplified if it were possible to automatically record which network device occupies which position within the daisy chain. In this case, the corresponding table with the assignment of location numbers and network devices can be created from the known wiring diagram.

[0010] It is therefore an object of the present invention to provide a method for determining a chain position of a network participant within an Ethernet daisy chain topology. A further object is to provide an agricultural arrangement with a plurality of network participants with which this method can be implemented.

[0011] This object is achieved by a method and an agricultural facility having the features of the respective independent claim. Advantageous embodiments and further developments are the subject of the dependent claims. A method according to the invention of the type mentioned at the outset is characterized by the following steps: In a first step (a), one of the two ports of the Ethernet gateway is deactivated and then, in a step (b), a status message from one of the network participants is recorded which relates to a non-connected port. In a step (c), an identification number of the network participant in question is extracted from the status message and assigned to a first chain position. In a step (d), the other port of the network participant in question is then deactivated.Subsequently, steps (b) to (d) are repeated until all network participants have been recorded with their identifier, whereby in the repetitions of step (c) the following, in particular ascending or descending, chain positions are assigned.

[0012] In order to compensate for the failure of a network line in the Ethernet daisy chain topology, the network participants have the ability to detect a port that is not connected to an active port of another network participant and to report this to the switch. In a method according to the invention, the network participants are further configured to deactivate a port upon request. The method according to the invention then uses these options to query information on the positions of the network participants within the daisy chain by specifically deactivating ports. The chain is successively shortened from one end to the other by deactivating ports and thus "making network participants invisible", and the network participant at the end of the chain can be identified.Because the port deactivation is only temporary, the entire chain can be reactivated after all network participants have been detected and is then ready for regular network operation again.

[0013] The gateway and the network participants are initially directly involved in carrying out the method. The method can be coordinated by a controller of the gateway itself, e.g. following a request from a higher-level controller or by a service computer that is connected to the gateway via a network. It goes without saying that the higher-level controller or the service computer can be connected to the gateway via an intranet or the internet. The method can also be coordinated by a unit external to the gateway, e.g. the higher-level controller or the service computer. In an advantageous embodiment, the deactivation of a network participant's port can be lifted by the network participant itself after a predetermined time has elapsed after the port has been deactivated, e.g. by the network participant starting a timer after deactivating a port, after which the port is reactivated.

[0014] In a further embodiment, the deactivation of a port can be immediately terminated by the network participant when it detects that a connection to another network participant or the Ethernet gateway has been established again on its other port. In this case, the entire daisy chain can be reactivated successively and without waiting times by expiring individual timers by reactivating the previously deactivated port of the Ethernet gateway.

[0015] In a further advantageous embodiment of the method, it can be provided that the actions in steps (b) and / or (d) are performed independently by the respective network participant. Alternatively, the status message in step (b) and / or the deactivation of the port in step (d) can also be performed by the network participant upon request by the gateway or a unit externally connected to it.

[0016] As a result of the process, a table can be created, for example, by the Ethernet gateway or an external unit. Starting with the initially deactivated port, this table uniquely displays the identification numbers, e.g., IP addresses and / or MAC addresses, of the network nodes and their positions within the daisy chain. Using a predefined wiring diagram of the arrangement, the identification numbers of the network nodes can then be uniquely assigned to the actual network nodes.

[0017] An arrangement according to the invention comprising agricultural implements, each of which has at least one network interface and is connected as network participants to a gateway in an Ethernet daisy chain topology, is configured to carry out the aforementioned method. The arrangement advantageously comprises a plurality of similar implements and is, for example, an arrangement of a plurality of milking stations, in particular a milking carousel. This results in the advantages described in connection with the method. The invention is explained in more detail below using exemplary embodiments with the aid of figures. The figures show:

[0018] Fig. 1 is a schematic representation of an arrangement of network participants and a gateway in an Ethernet daisy chain topology;

[0019] Fig. 2a-2e each show a schematic representation of the arrangement according to Fig. 1 in different operating states during the implementation of a method according to the invention;

[0020] Fig. 3-4 each show a schematic representation of an arrangement of a plurality of milking places with network participants in a milking parlor; and

[0021] Fig. 5 is a schematic representation of an arrangement of a plurality of milking places with network participants in several milking parlors.

[0022] Figure 1 shows, by way of example and in the form of a block diagram, an arrangement of several, here four, devices 2.1-2.4, which are coupled to a gateway 1 in a daisy chain topology.

[0023] Gateway 1 can, for example, be an Ethernet switch or another network device capable of connecting the daisy chain of devices 2.1-2.4 to a higher-level network. Gateway 1 itself can be configured to coordinate the procedure described below. The execution of the procedure can be initiated by a higher-level unit connected to Gateway 1 via the network, e.g., a milking parlor control unit. It is also conceivable for the procedure to be coordinated by the higher-level unit itself.

[0024] The gateway 1 has two ports (network connections) 11a, 11b, which are coupled to the ends of the daisy chain. In the daisy chain itself, the devices 2.1-2.4 are arranged serially one behind the other. Each of the devices 2.1-2.4 has a network interface 21.1-21.4, which, like the gateway 1, provides two ports, which are identified in Figure 1 by the reference numerals 22.1a-22.4a for a first port and 22.1b-22.4b for a second port. Ports with the index "a" are each connected to the port with the index "b" of their neighbor via network connections 3, resulting in the loop arrangement visible in Figure 1.

[0025] In the arrangement shown, for example, devices 2.1-2.4 are milking places of a milking parlor, whose control devices have the network connections shown for monitoring and / or control purposes.

[0026] After connecting the components shown, each network participant 21.1-21.4 is assigned an IP address, which is designated 23.1-23.4 in Figure 1. Furthermore, each network participant 21.1-21.4 has a permanently assigned MAC address 24.1-24.4, which is also shown in Figure 1. After wiring the components, gateway 1 knows how many network participants 21.1-21.4 are present and which IP address 23.1-23.4 or MAC address 24.1-24.4 they each have.

[0027] However, the gateway 1 or the higher-level unit does not know in which order these detected network participants 21 .1-21 .4 are located within the daisy chain.

[0028] The exemplary IP addresses 23.1-23.4 in Figure 1 indicate, for example, that these addresses are not assigned successively and in ascending order in the arrangement of the network participants 21 .1-21 .4 within the chain, but rather this assignment is done randomly.

[0029] During operation of the arrangement shown in Figure 1, an interruption is usually deliberately created at one point in the loop by deactivating one of the ports 11a, b or 22.1a, b - 22.4a, b, so that each network participant 21.1-21.4 can only be reached from one direction in order to prevent data collisions. For this purpose, the RSTP (Rapid Spanning Tree Protocol) technology known in Ethernet networks can be used, for example, which leads to the automatic creation of a tree-like network structure during operation. If a network connection 3 actually fails during operation or one of the aforementioned ports 11a, b or 22.1a, b - 22.4a, b is inoperable, the previously deactivated port is automatically reactivated, so that the actual fault location represents the interruption point in the loop. A fault location can be compensated in this way.A method according to the invention for detecting the position of a network participant within the daisy chain is explained below with reference to Figs. 2a-2e. These figures each show the block diagram already shown in Figure 1 in various method steps for different states of the involved ports 11a, b and 22.1a, b - 22.4a, b.

[0030] The status of ports 11 a, b or 22.1 a, b - 22.4a, b is indicated by the symbols "0", "1 +", and "1-" on the respective port. The symbol "0" indicates a deactivated port. The symbol "1 +" indicates an activated port that detects that it is connected to a likewise activated and functional port of a neighboring network node or the gateway. The symbol "1-" indicates an activated port that detects that there is no connection to an active and functional port of a neighboring network node.

[0031] In a preparatory step of the process, Gateway 1 itself or the higher-level unit via Gateway 1 can send a command to the daisy chain that marks the start of the process and, if necessary, puts network nodes 21.1-21.4 into initialization mode. In response, network nodes 21.1-21.4 acknowledge receipt and send their current IP address 23.1-23.4 and their MAC address 24.1-24.4 back to Gateway 1 or the higher-level unit. If a device table has not yet been created, this is done now by saving the number of network nodes 21.1-21.4 and the assignment of IP addresses 23.1-23.4 to MAC addresses 24.1-24.4.

[0032] In a first method step (a), gateway 1 deactivates one of the two ports 11a, 11b, for example, the first port 11a. This is represented in Figure 2a by the symbol "0" at port 11a of gateway 1. As a result, network participant 21.1 detects that its port 22.1b has no active connection and sets its status to "1-." All other ports in the system have the status "1+."

[0033] In the next step (b), network device 2.1, which has detected the status change at its port 22.1b, sends this status change to gateway 1 (or the higher-level unit), which then knows that this device 2.1 with network device 21.1 and the IP and MAC addresses 23.1 and 24.1 transmitted with the status report is the device directly connected to port 11a, i.e., the device with position number 1 in the daisy chain. Network devices 21.1-21.4 can be configured to independently send a corresponding status report to gateway 1 or the higher-level unit when they detect a status change of one of their ports 22.1a,b - 22.4a,b. Alternatively, the gateway 1 or the higher-level unit can send a request to the daisy chain and request the network participants 21.1-21.4 to report the status of their ports 22.1a, b - 22.4a, b.

[0034] In the next step (c), network participant 21.1 deactivates port 22.1a, which was previously active. The resulting state is shown in Figure 2b. Deactivation can occur either following an immediate request from gateway 1 or the higher-level unit in a direct message to network participant 21.1, since its IP address 23.1 is known after receipt of the status message. Alternatively, gateway 1 or the higher-level unit can send a request to all network participants 21.1-21.4, requesting that those network participants 21.1-21.4 with one port in the state "1-" deactivate the other of their ports. Upon sending such a request, network participant 21.1 would also deactivate port 22.1a. As a further alternative, it is also conceivable that a network participant 21.1-21.1 that is in initialization mode4 automatically deactivates its other port after detecting the unconnected port with the status “-1” and sending the status message about it.

[0035] After this step, step (b) is repeated, namely that the deactivated port – now port 22.1a of network participant 21.1 – is detected by network participant 21.2. In Figure 2b, this can be seen by port 22.2b assuming the state "1-". Network participant 21.2 then sends the corresponding message, indicating that it has detected a connection failure at port 22.2b, to gateway 1 or the higher-level unit, which can then assign the transmitted IP address 23.2 and the transmitted MAC address 24.2 to network participant 21.2 and the second position in the daisy chain. Device 2.2 with network participant 21.2 is again requested to deactivate its other port, port 22.2a, or deactivates it independently, resulting in the state shown in Figure 2c.

[0036] Steps (b) and (c) are then repeated until the last device 2.4 directly connected to gateway 1 at port 11b with network node 21.4 has deactivated its port 22.4a, which gateway 1 detects at port 11b. This is shown in Figure 2d. The gateway thus knows that all network nodes 21.1-21.4 have been detected, including their positions within the daisy chain. Gateway 1 or the higher-level unit has thus completed the device table with the position within the daisy chain, also called the "chain position."

[0037] The detection process is completed with this step, after which the daisy chain can be returned to a state of normal network operation. This can be done, for example, by device 2.1 or its network participant 21.1 changing the state of port 22.1a from "deactivated" back to "activated." For this purpose, a timer can be provided in each network participant 21.1-21.4, which is started when the respective port 22.1a-22.4a is deactivated. After the timer expires, the port's deactivation is canceled. As a result, the connected port—in this process state, port 22.2b of network participant 21.2—also detects that it is again connected to an active port and also sets its state to "1+." This is shown in Figure 2e.

[0038] Once the timers for devices 2.2-2.4 have expired, the entire daisy chain is operational again. To accelerate the process, it can be provided that when an active connection is detected at one of the ports, the other port is automatically reactivated as well. In this case, network device 2.2 would immediately activate its port 22.2a, starting from the state shown in Figure 2e (i.e., after the timer for device 2.1 has expired and port 22.1a has been reactivated). In a chain reaction, the activation then extends almost immediately to network devices 2.3 and 2.4.

[0039] In an alternative embodiment, this chain reaction can also be triggered directly by gateway 1 by activating port 11a, which would cause device 2.1 and subsequently devices 2.2-2.4 to also activate their deactivated ports, even if no expiring timer is provided in the network devices.

[0040] The device table created in this way, which was set up, for example, by Gateway 1 or the higher-level unit, can now be used by any application that benefits from or depends on a location assignment. It can also be used, for example, to instruct a DHCP (Dynamic Host Configuration Protocol) server to assign the desired predefined IP addresses, which may reflect the location number, to the individual devices 2.1-2.4 or their network participants 21.1-21.4. Furthermore, names can be automatically assigned to the IP addresses in the network by a DNS (Domain Name Service) service using this device table; these names also depend on the location number or reflect it. If there are connection problems between devices 2.1-2.4, the created table can also be used to specifically specify between which devices 2.1-2.4 the problem exists, which makes troubleshooting easier for service technicians.

[0041] Figure 3 shows a block diagram or wiring plan of a milking carousel as an example of a milking parlor arrangement in which the described method can be used.

[0042] A plurality of devices 2 are connected in the form of a daisy chain with connections 3 to each other and to two ports 11a, 11b of a gateway 1. As in the example in Figure 1, the devices 2 each have a network interface (corresponding to network participants 21.1 - 21.4 in Figure 1) with two ports, which are not shown in detail here for reasons of clarity. In total, the milking carousel shown comprises 16 devices 2.

[0043] Devices 2 correspond to the milking places in the milking parlor layout and are therefore also referred to as milking places 2 below.

[0044] When carrying out the method described above, the milking stations 2 can be recorded starting from port 11a, including an assignment of the IP or MAC addresses to the individual stations along the milking carousel.

[0045] Assuming that the milking parlor 2 connected to port 11a is "place number 1" of the milking carousel, the detected position of each of the milking places 2 in the daisy chain directly represents its place number in the milking carousel. Assigning "place number 1" to another of the milking places 2 results in a corresponding offset compared to the determined position number in the daisy chain. In this way, the method according to the invention can easily automatically detect the IP and / or MAC addresses of the individual milking places 2 and their place numbers. Figure 4 shows a comparable milking carousel with a plurality of milking places 2 which, in contrast to the embodiment in Figure 3, are not connected to one another in a daisy chain, but in three separate daisy chains.The milking stations are identified as device groups 4, 5 and 6 in Figure 4, with the milking stations of each of the device groups 4-6 being linked by a daisy chain.

[0046] Device group 4 comprises a daisy chain of six milking stations 2, which are connected to two ports 11a, 11b of gateway 1. Device group 5 comprises three milking stations 2, which are connected in a daisy chain to two ports 12a, 12b. Finally, the third device group 6 comprises seven milking stations 2, which are connected in a daisy chain to ports 13a, 13b of gateway 1.

[0047] The previously described procedure for determining an assignment of IP and / or MAC address to a position of a device 2 in a daisy chain can now be carried out separately for each of the three device groups 4-6, i.e. each of the daisy chains. The wiring diagram shows that with the wiring shown, the first detected device 2 in the second daisy chain (device group 5) is connected to the last device in the first daisy chain (device group 4). Furthermore, the first device in the third daisy chain (device group 6) is connected to the last device in the second daisy chain (device group 5). Using this information from the wiring diagram, the three separately created device tables for the individual daisy chain can be combined, and IP or MAC addresses can be assigned to position numbers on the milking carousel.Here again, only one assignment needs to be specified, which concerns the milking place with place number 1.

[0048] It should be noted that the three device groups 4-6 do not necessarily have to be connected to one another as shown in the example in Figure 4. The groups can also be wired with different orientations and / or interlaced; however, the information regarding how the groups are related in order to be assigned a sequentially ascending location number is then required for the assignment to an actual physical location on the milking carousel.

[0049] Finally, Figure 5 shows an arrangement of a total of six device groups 4-9 of milking places 2, which in this case are not assigned to a common milking parlor, but (as in the milking carousel in Figures 3 and 4), but rather to six different milking parlors. All of these milking parlors or device groups 4-9 are served by a common gateway 1. Gateway 1 has twelve ports 11a-16a and 11b-16b, each of which is connected in pairs to one of the daisy chains. Device groups 4-9 can, for example, be clusters of milking places 2, which are also spatially close to one another within the groups, so that the grouping reflects, to a certain extent, the spatial positioning on an agricultural farm.In the example of Figure 5, the method according to the invention can also be carried out independently for each of the groups 4-9 in order to detect the position of the individual milking stations 2 within one of the device groups 4-9 and within a daisy chain.

[0050] Reference symbol

[0051] 1 gateway

[0052] 11a first port 11b second port

[0053] 12a-16a further first port

[0054] 12b-16b additional second port

[0055] 2, 2.1-2.4 Device (milking place) 21.1-21.4 Network participants

[0056] 22.1a-22.4a first port

[0057] 22.1b-22.4b second port

[0058] 23.1-23.4 IP address

[0059] 24.1-24.4 MAC address

[0060] 3 Network connection

[0061] 4-9 Equipment group (milking parlor)

Claims

Claims 1. Method for determining a chain position of a network participant (21.1-21.4) in an Ethernet network, wherein the network participants (21.1-21.4) are connected to each other in a daisy chain and the daisy chain is connected at both ends to a port (11a-16a, 11 b-16b) of an Ethernet gateway (1) is coupled, comprising the following steps: (a) Disabling one of the two ports (11 a-16a, 11 b-16b) of the Ethernet gateway (1); (b) Capture a status message from one of the network participants (21.1- 21.4), which concerns the unconnected ports (22.1a-22.4a, 22.1b-22.4b) of the network participant concerned (21.1-21.4); (c) Extracting at least one identification number from the status message of the network participant concerned (21.1-21.4) and assigning a first chain position to the identification number; (d) Disabling the other port (22.1a-22.4a, 22.1b-22.4b) of the network participant concerned (21.1-21.4); and (e) Repeat steps (b) to (d) until all network participants (21.1- 21.4) are recorded with their identification number, whereby subsequent chain positions are assigned in the repetitions of step (c).

2. The method according to claim 1, wherein the determined chain positions are recorded together with the identification numbers in a device table.

3. Method according to claim 1 or 2, wherein the identification numbers are IP addresses (23.1-23.4) and / or MAC addresses (24.1-24.4).

4. Method according to one of claims 1 to 3, wherein the status message in step (b) is constantly issued by the network participant (21.1-21.4) concerned after the detection of the unconnected port.

5. Method according to one of claims 1 to 3, wherein the status message in step (b) is issued upon request by the relevant network participant (21.1-21.4).

6. Method according to any one of claims 1 to 5, wherein the deactivation of the other port (22.1a-22.4a, 22.1b-22.4b) in step (d) is carried out independently by the network participant concerned (21.1-21.4) after recognizing the unconnected port.

7. Method according to any one of claims 1 to 5, wherein the deactivation of the other port (22.1a-22.4a, 22.1b-22.4b) in step (d) is carried out after recognizing the unconnected port at the request of the network participant concerned (21.1-21.4).

8. Method according to any one of claims 1 to 7, wherein after step (e) the network participants (21.1-21.4) and / or the gateway (1) reactivate the deactivated ports (11a-16a, 11b-16b, 22.1a-22.4a, 22.1b-22.4b).

9. Method according to any one of claims 1 to 8, wherein the network participants (21.1-21.4) reactivate the ports (22.1 a-22.4a, 22.1 b-22.4b) independently after a predetermined time following deactivation.

10. Method according to any one of claims 1 to 8, wherein the network participants (21.1-21.4) reactivate the ports (22.1 a-22.4a, 22.1 b-22.4b) independently when they detect a connection again on the other of the ports (22.1a-22.4a, 22.1b-22.4b).

11. Arrangement of agricultural equipment (2), each having at least one network interface which is interconnected as a network participant (21.1-21.4) with a gateway (1) in an Ethernet daisy chain topology, characterized in that the arrangement is set up to carry out a method according to one of claims 1 to 5.

12. Arrangement according to claim 11, wherein the devices (2) are milking places, in particular a milking carousel.