Abstract:
Method, apparatuses, and software are described, in which an adapter in an EtherNet/IP network may determine whether a first redundant owner connection between the adapter and a first scanner is open. If it is determined that the first redundant owner connection is not open, then a network status light or other indicator of the adapter may be caused to emit a solid green color or otherwise indicate a first status if a second redundant owner connection between the adapter and a second scanner is open, and to emit a flashing red color or a flashing green color (or otherwise indicate a second or third status) if no redundant owner connection to the adapter is open.

Description:
BACKGROUND 
     The existing ODVA network status light standard in an EtherNet/IP network does not adequately address the situation in which there are multiple redundant owners for a given adapter. For instance, if one of a plurality of redundant owners times out from a lost a network connection with an adapter, then the network status light of the adapter would begin flashing red. While this may make sense in the environment of a single exclusive owner, this would likely be confusing to the user of the adapter in a multiple redundant owner scenario. Thus, an ODVA-compliant network status light would only take into account the status of the timed-out owner, and not the status of the new redundant owner. Thus, in a redundant owner scenario, the ODVA-compliant network status light may operate in a misleading manner. 
     SUMMARY 
     Various aspects as described herein are directed to apparatuses, systems, methods, and software that may cause a network status indicator, such as a network status light, to operate in a manner more appropriate for a multiple redundant owner scenario. 
     For example, various aspects as described herein are directed to a method comprising determining, by an adapter (or other slave device) in an EtherNet/IP network, whether a first redundant owner connection between the slave device and a first scanner (or other master device) is open. The method may further comprise, if it is determined that the first redundant owner connection is not open, then causing a network status indicator of the adapter device to indicate a first status if a second redundant owner connection between the adapter device and a second scanner device is open, and to emit a second status or a third status if no redundant owner connection to the slave device is open. 
     Further aspects may be directed to, for example, an apparatus, comprising a processor, a network status indicator, and a communication interface configured to be coupled to a network the process may be configured to cause the network status indicator to indicate a first status when at least one of a plurality of redundant owner connections to the communication interface is open, even if another of the plurality of redundant owner connections is closed or timed out, and to cause the network status indicator to indicate a second status or a third status when there are no open redundant owner connections to the communication interface. 
     Still further aspects may be directed to, for example, an apparatus, comprising a processor and a network status light. The processor may be configured to determine whether a first redundant owner connection between the apparatus and a first scanner is open, and if it is determined that the first redundant owner connection is not open, cause the network status light to emit a solid green color if a second redundant owner connection between the apparatus and a second scanner is open, and to emit a flashing red color or a flashing green color if no redundant owner connection to the apparatus is open. 
     Even further aspects may be directed to, for instance, a non-transitory computer-readable medium storing computer-executable instructions for a computer to perform steps. The steps may comprise causing a network status light of an apparatus to emit a solid green color when at least one of a plurality of redundant owner connections to the apparatus is open, even if another of the plurality of redundant owner connections is closed or timed out, and causing the network status light to emit a flashing red color or a flashing green color when there are no open redundant owner connections to the apparatus. 
     These and other aspects of the disclosure will be apparent upon consideration of the following detailed description. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A more complete understanding of the present disclosure and the potential advantages of various aspects described herein may be acquired by referring to the following description in consideration of the accompanying drawings, in which like reference numbers indicate like features, and wherein: 
         FIG. 1  is a block diagram of an example network of devices, in accordance with one or more aspects as described herein; 
         FIG. 2  is a block diagram of an example computing device, in accordance with one or more aspects as described herein; and 
         FIG. 3  is a flowchart of example steps that may be performed, in accordance with one or more aspects as described herein. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  is a block diagram of an example network (or portion thereof) of devices that may be used to implement one or more of the features and functions as described herein. The network may include one or more master/slave and/or producer-consumer relationships between devices. For example, the network may include one or more devices functioning as master devices, such as scanners  101 -A,  101 B, and  101 C, that may each be coupled to and act as a master to one or more devices each functioning as a slave device, such as adapter  102 . It will be understood that the network may include many more master devices and/or slave devices with many more master/slave relationships, and that  FIG. 1  shows just one family of master/slave relationships for ease of understanding. 
     The network of  FIG. 1  may be any type of network, such as but not limited to an EtherNet/IP network. The network may also follow one or more network standards, such as one or more network protocols for the devices to communicate with each other. For example, an EtherNet/IP network standard may be followed by the network, such as the Open Device Vendors Association (ODVA) standard. The ODVA standard specifies various behaviors and communications between the devices, including the master/slave relationship. For instance, according to the ODVA standard as described in “The CIP Networks Library, Volume 1, Common Industrial Protocol (CIP)”, published by ODVA, the adapter  102  may have an exclusive owner (master), such as scanner  101 -A. Or, according to the ODVA standard, the adapter  102  may have multiple redundant owners, such scanners  101 -A,  101 -B, and  101 -C. Under the redundant owner scenario, only one of the scanners  101  is the owner at any given time. If that owner loses a network connection with the adapter  102  or is otherwise unable to carry out is ownership function, then another one of the scanners  101  automatically becomes the owner. 
     The adapter  102  may include a network status indicator, such as one or more network status lights  103 , for indicating a network status from the point of view of adapter  102 . The network status indicator may operate in accordance with a network standard, such as the above-mentioned ODVA standard. The network status indicator may be capable of producing, for example, various different colors and/or light patterns (e.g., flashing or steady) to indicate the status. Examples of status indications used by the ODVA standard (where the network status indicator is a network status light  103 ) include a steady green, a steady red, a flashing green, a flashing red, alternate flashing between green and red, and an off (non-lit) status. Other status indications, such as other colors, flashing patterns, and/or color patterns may also be produced as desired. Where the network status light  103  is only a single physical light, the network status light  103  may be configured to produce the various colors, such as using a multi-color light-emitting diode (LED). Where the network status light  103  includes more than one physical light, then each of the physical lights may be dedicated to producing a different one of the colors and may be selectively used to produce the desired color at a given time. For instance, the network status light  103  may actually include both a green light-emitting element and a separate red light-emitting element. 
     Moreover, the network status indicator does not necessarily need to include any lights, and may be embodied in alternate ways. For example, the network status indicator may include one or more audio emitting devices, tactile output devices (e.g., vibration and/or braille devices) video displays, etc. Moreover, the network status indicator may be located entirely within the adapter  102 , partially within the adapter  102  and on an external surface of the adapter  102 , or entirely on an external surface of the adapter  102 . Any status indication provided by the network status indicator may or may not be discernable from a location outside of the adapter  102 . For example, it may be that the indication of the status is discernible only by opening a door of the adapter  102  or by probing the adapter  102  via an external device. The network status indicator may even be entirely external and/or physically separate from the adapter  102  itself, such as a network status indicator device that is connected wirelessly or via wire to the adapter  102 . 
     As discussed above, the particular indications of status (e.g., colors and/or patterns) by the network status indicator may depend upon the particular device and/or the network standards used. For example, where the adapter  102  is an EtherNet/IP based adapter device, the adapter  102  may be configured to operate the network status indicator in accordance with the ODVA standard, such as that set forth in “The CIP Networks Library, Volume 2, EtherNet/IP Adaptation of CIP,” published by ODVA. According to this standard, the network status indicator (when embodied as the network status light  103 ) may operate as follows, assuming that the network is configured such that only a single exclusive owner controls the adapter  102 . Upon power-up or reset, the network status light  103  would alternately flash between green and red during power-on self-test (POST). Once POST is complete, the network status light  103  would turn off until an IP address for the adapter  102  is configured, at which point the network status light  103  would flash green. Then, once a Common Industrial Protocol (CIP) connection is established, the network status light  103  would emit a steady green. If the exclusive owner (e.g., scanner  101 -A) subsequently times out (e.g., due to a lost network connection with the adapter  102 ), then the network status light  103  would begin flashing red. The network status light  103  would continue flashing red until an exclusive owner is established (for instance, when a previously-open-and-then-closed redundant owner connection is re-opened, or when a previously normally-closed redundant owner connection is opened). 
     Unfortunately, the existing ODVA network status light standard as described above does not adequately address the situation in which there are multiple redundant owners for a given adapter. For instance, under the existing ODVA network status light standard as discussed above, if one of the redundant owners (e.g., scanner  103 -A) times out from a lost a network connection with the adapter  102 , then the network status light  103  of the adapter  102  would begin flashing red. While this may make sense in the environment of a single exclusive owner, this would likely be confusing to the user of the adapter  102  in a multiple redundant owner scenario. In other words, in a redundant owner scenario under the existing ODVA standard, the network status light  103  would flash red even though another of the redundant owners (e.g., scanner  103 -B) may have immediately taken over as the new owner of the adapter  102 . Thus, the ODVA-compliant network status light  103  would only take into account the status of the timed-out owner, and not the status of the new redundant owner. Thus, in a redundant owner scenario, the ODVA-compliant network status light  103  may operate in a misleading manner. 
     Another redundant-owner-scenario problem with the current ODVA standard is described below in connection with Tables 1A and 1B. In the example of Table 1A, scanner  101 -A is the current owner, and all owner connections are available. In this case, the network status light may indicate a steady green. However, at a subsequent time, as shown in the example of Table 1B, one of the connections with one of the redundant owners (e.g., scanner  101 -B) may be lost and timed out. Even if the lost connection is not the connection for the current redundant owner (scanner  101 -A, according to Table 1A), and despite the fact that the adapter  102  actually still maintains a good connection with the current owner (scanner  101 -A), the network status light  103  nevertheless may emit flashing red. This network status light operation also does not make sense and may be misleading to the user of the adapter  102 . 
     
       
         
               
               
               
               
             
           
               
                 TABLE 1A 
               
               
                   
               
               
                   
                 CONNECTION 
                   
                   
               
               
                 SCANNER 
                 STATUS 
                 OWNERSHIP 
               
               
                   
               
             
             
               
                 101-A 
                 yes (open) 
                 yes 
                 network status light 
               
               
                 101-B 
                 yes (open) 
                 no 
                 is STEADY 
               
               
                 101-C 
                 yes (open) 
                 no 
                 GREEN 
               
               
                   
               
             
          
         
       
     
     
       
         
               
               
               
               
             
           
               
                 TABLE 1B 
               
               
                   
               
               
                   
                 CONNECTION 
                   
                   
               
               
                 SCANNER 
                 STATUS 
                 OWNERSHIP 
               
               
                   
               
             
             
               
                 101-A 
                 yes (open) 
                 yes 
                 network status light 
               
               
                 101-B 
                 no - timed out 
                 no 
                 is FLASHING 
               
               
                   
                 or closed 
                   
                 RED, even though 
               
               
                 101-C 
                 yes (open) 
                 no 
                 current owner 
               
               
                   
                   
                   
                 maintains good 
               
               
                   
                   
                   
                 connection 
               
               
                   
               
             
          
         
       
     
     Example embodiments showing how the ODVA standard may be modified to correct for problems such as these will be described further below. 
       FIG. 2  is a block diagram of an example computing device  200  that may be used to partially or fully embody any or all of the scanners  101  and/or the adapter  102  of  FIG. 1  (and any other devices in the network). Computing device  200  may include hardware that may execute software to perform specific functions. The software, if any, may be stored on a tangible and/or non-transitory computer-readable medium  202  in the form of computer-readable instructions. Computing device  200  may read those computer-readable instructions, and in response perform various steps as defined by those computer-readable instructions. Thus, any functions, steps, calculations, devices, and other elements described herein may be may be implemented by a computer, such as by reading and executing computer-readable instructions for performing those functions, and/or by any hardware subsystem (e.g., a processor  201 , such as a central processing unit, and/or other circuitry) from which computing device  200  is composed. Additionally or alternatively, any of the above-mentioned functions may be implemented by the hardware of computing device  200 , with or without the execution of software. For example, computing device  200  may be or include one or more microprocessors, central processing units (CPUs), and/or other types of circuitry configured to perform some or all of the functions attributed to computing device  200 . In such embodiments, processor  201  may be implemented as or otherwise include the one or more microprocessors, CPUs, ASICs, and/or other types of circuitry. 
     A computing device may include any electronic, electro-optical, and/or mechanical device, or system of multiple physically separate or integrated such devices, that is able to process and manipulate information, such as in the form of data. Non-limiting examples of a computing device include one or more personal computers (e.g., desktop, tablet, or laptop), mainframes, servers, cellular phones (which may be “smart phones”), personal digital assistants, and/or a system of these in any combination or sub-combination. In addition, a given computing device may be physically located completely in one location or may be distributed amongst a plurality of locations (i.e., may implement distributive computing). A computing device may be or otherwise include a general-purpose computing device and/or a dedicated computing device configured to perform only certain limited functions. 
     Computer-readable medium  202  may include not only a single tangible and/or non-transitory medium or single type of such medium, but also a combination of one or more such media and/or types of such media. Examples of embodiments of computer-readable medium  202  include, but are not limited to, one or more memories, hard drives, optical discs (such as CDs or DVDs), magnetic discs, and magnetic tape drives. Computer-readable medium  202  may be physically part of, or otherwise accessible by, computing device  200 , and may store computer-readable instructions (e.g., software) and/or computer-readable data (i.e., information that may or may not be executable). 
     Computing device  200  may also include a user input/output interface  203  for receiving input from a user (e.g., via a keyboard, mouse, touch screen, an audio microphone, camera, and/or remote control) and/or for providing output to the user (e.g., via a touch screen or other display device, an audio speaker or piezoelectric element, a printer, and/or the network status indicator). Computing device  200  may further include a communication input/output interface  204  for communicating with other devices, such as other devices on the network, via wire and/or wirelessly. 
     As discussed previously, the network status indicator (e.g., the network status light  103 ), when compliant with the above-mentioned ODVA standard, may misleadingly emit a flashing red light when an owner connection is timed out, even though a redundant owner may have successfully taken over, or even though the timed-out connection is not the connection to the current redundant owner.  FIG. 3  is a flow chart showing example steps that may be performed by the adapter  102  in order to provide a more useful network status indication in a redundant owner network configuration. 
     In accordance with the example of  FIG. 3 , during POST of the adapter  102 , the network status indicator may alternately flash between green and red or provide some other type of appropriate indication of status, referred to generically herein as “Status A” (step  301 ). Upon completion of POST, the network status indicator may turn off or provide some other appropriate indication of status, referred to generically herein as “Status B” (step  302 ) until the adapter  102  determines that an IP address of the adapter  102  has been configured. At that point, the network status indicator may emit flashing green or provide another appropriate indication of status, referred to generically herein as “Status C” (step  303 ). Once the adapter  102  detects that an owner connection has been established with one of the redundant owners (e.g., scanner  101 -A), the network status light  103  may emit steady green or present yet another appropriate indication of status, referred to generically herein as “Status D”, (step  304 ), which would indicate a normal network status. 
     If the network adapter  102  detects that the owner connection with the current owner is lost or purposely closed during normal network status, then it may be expected that another of the redundant owners (e.g., scanner  101 -B) may take over as the new current owner. As long as the adapter  102  detects that there is a redundant owner that has taken over within a predetermined timeout period (as measured by the adapter  102 ) after the original CIP connection is lost, the process may remain at step  304 , and thus the network status indicator may continue to indicate Status D, e.g., a steady green. This is in contrast to the previously-discussed conventional ODVA standard, in which the loss of a redundant owner would cause the network status light to begin flashing red, even if another redundant owner successfully took over. 
     If, however, the adapter  102  does not detect a new redundant owner that has taken over within the timeout period, then the process may move to step  305 , in which the network status indicator would begin emitting flashing red or provide another appropriate indication of status, referred to generically herein as “Status E.” Thus, Status E (e.g., flashing red) may be presented only if the current redundant owner connection has timed out and there are no available redundant owners within the timeout period. If, at any time while the process is at step  305 , the adapter  102  detects that one of the redundant owners takes over as the current owner, then the process may move back to step  304 , such that the network status indicator would again provide Status D (e.g., emit a steady green). 
     Also, if the adapter  102  detects that there are no CIP connections available, and if all I/O connections have been purposely closed (not timed out), then the process may move from step  304  to step  303 , such that the network status indicator may begin indicating Status C (e.g., by emitting a flashing green). This may distinguish between the situation where there is no owner due to a timeout (e.g., flashing red) and the situation where there is no owner due to purposely closing the connections (e.g., flashing green). 
     If, at any time, the adapter  102  determines that the IP address of the adapter  102  is lost, then the process may move to step  302 , such that the network status indicator indicates Status B (e.g., the network status light  103  turns off). The network status indicator may remain at Status B until an IP address is configured, at which point the process may again move to step  303  as previously described. And, if at any time the adapter  102  determines that there is duplicate IP address in the network that is the same as the IP address of the adapter  102 , then the process may move to step  306 , in which the network status indicator would emit steady red or provide yet another appropriate status indication, referred to herein generically as “Status F.” The Status F indication would continue until the network adapter  102  determines that the duplicate IP address situation has been corrected, at which point the process may move back to step  303 , and the network status indicator may again indicate Status C (e.g., by emitting a flashing green color) as described previously. 
     Thus, as shown by way of example in Tables 2A and 2B below, where the network status indicator includes the network status light  103 , the network status light  103  may remain a steady green, even if the adapter  102  detects that the connection is lost by a non-current-owner. Tables 2A and 2B are shown in time order. That is the scenario of Table 2B occurs after the scenario of Table 2A. 
     
       
         
               
               
               
               
             
           
               
                 TABLE 2A 
               
               
                   
               
               
                   
                 CONNECTION 
                   
                   
               
               
                   
                 STATUS TO 
                 OWNERSHIP 
                   
               
               
                 SCANNER 
                 ADAPTER 
                 OF ADAPTER 
               
               
                   
               
             
             
               
                 101-A 
                 yes (open) 
                 yes 
                 network status light 
               
               
                 101-B 
                 yes (open) 
                 no 
                 is STEADY 
               
               
                 101-C 
                 yes (open) 
                 no 
                 GREEN 
               
               
                   
               
             
          
         
       
     
     
       
         
               
               
               
               
             
           
               
                 TABLE 2B 
               
               
                   
               
               
                   
                 CONNECTION 
                   
                   
               
               
                   
                 STATUS TO 
                 OWNERSHIP 
                   
               
               
                 SCANNER 
                 ADAPTER 
                 OF ADAPTER 
               
               
                   
               
             
             
               
                 101-A 
                 yes (open) 
                 yes 
                 network status light 
               
               
                 101-B 
                 no - timed out 
                 no 
                 remains STEADY 
               
               
                   
                 or closed 
                   
                 GREEN 
               
               
                 101-C 
                 yes (open) 
                 no 
               
               
                   
               
             
          
         
       
     
     And, as shown in Tables 3A and 3B below, the network status light  103  may remain a steady green if adapter  102  detects that the current owner connection is lost, as long as the adapter  102  detects that another redundant owner has taken over. Tables 3A and 3B are shown in time order. That is the scenario of Table 3B occurs after the scenario of Table 3A. Referring to Table 3C below, if all of the redundant owners assigned to the adapter  102  are not available to take over as the current owner because the connections to the redundant owners have timed out, then the process of  FIG. 3  would move to step  305 , and the network status light  103  would change to a flashing red. If all of the redundant owners are not available because all of the connections were purposely closed (rather than merely having timed out), then the process of  FIG. 3  would move to step  303 , and the network status light  103  would change to a flashing green. 
     
       
         
               
               
               
               
             
           
               
                 TABLE 3A 
               
               
                   
               
               
                   
                 CONNECTION 
                   
                   
               
               
                   
                 STATUS TO 
                 OWNERSHIP 
                   
               
               
                 SCANNER 
                 ADAPTER 
                 OF ADAPTER 
               
               
                   
               
             
             
               
                 101-A 
                 yes (open) 
                 yes 
                 network status light 
               
               
                 101-B 
                 yes (open) 
                 no 
                 103 is STEADY 
               
               
                 101-C 
                 yes (open) 
                 no 
                 GREEN 
               
               
                   
               
             
          
         
       
     
     
       
         
               
               
               
               
             
           
               
                 TABLE 3B 
               
               
                   
               
               
                   
                 CONNECTION 
                   
                   
               
               
                   
                 STATUS TO 
                 OWNERSHIP 
                   
               
               
                 SCANNER 
                 ADAPTER 
                 OF ADAPTER 
               
               
                   
               
             
             
               
                 101-A 
                 no - timed out 
                 no 
                 network status light 
               
               
                   
                 or closed 
                   
                 103 remains STEADY 
               
               
                 101-B 
                 yes (open) 
                 yes - took over 
                 GREEN 
               
               
                 101-C 
                 yes (open) 
                 no 
               
               
                   
               
             
          
         
       
     
     
       
         
               
               
               
               
             
           
               
                 TABLE 3C 
               
               
                   
               
               
                   
                 CONNECTION 
                   
                   
               
               
                   
                 STATUS TO 
                 OWNERSHIP 
                   
               
               
                 SCANNER 
                 ADAPTER 
                 OF ADAPTER 
               
               
                   
               
             
             
               
                 101-A 
                 no - timed out 
                 no 
                 network status light 
               
               
                   
                 or closed 
                   
                 103 begins 
               
               
                 101-B 
                 no - timed out 
                 no 
                 FLASHING GREEN 
               
               
                   
                 or closed 
                   
                 if all connections 
               
               
                 101-C 
                 no - timed out 
                 no 
                 are closed but not 
               
               
                   
                 or closed 
                   
                 from timing out, 
               
               
                   
                   
                   
                 and FLASHING 
               
               
                   
                   
                   
                 RED if the current 
               
               
                   
                   
                   
                 connection has 
               
               
                   
                   
                   
                 timed out and no 
               
               
                   
                   
                   
                 open redundant 
               
               
                   
                   
                   
                 connections are 
               
               
                   
                   
                   
                 available 
               
               
                   
               
             
          
         
       
     
     This mode of operation of the adapter  102  and the network status indicator may be much less confusing for the user of the adapter  102 . Now, under a redundant owner scenario, as long as the adapter  102  has at least one owner with a good connection (and assuming that there is no duplicate IP address or other problem), the network status indicator may, for example, emit a steady green, showing the user that the adapter  102  is exchanging IO data. 
     While embodiments of the present invention have been illustrated and described, it is not intended that these embodiments illustrate and describe all possible forms of the present invention. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the present disclosure. For example, while various light-based status indications have been discussed (e.g., steady green, flashing red, etc.), other types of status indications may be presented by the network status indicator. Examples of such other types of status indications may include intermittent or continuous vibrations, intermittent or continuous sounds, such as at specific frequencies or tones, specific video display outputs, specific braille outputs, and the like.