Patent Publication Number: US-10326643-B2

Title: Self-configuring fault-tolerant operational group

Description:
BACKGROUND 
     With the rapid technological developments in areas such as aviation, space travel, robotics, autonomous vehicles, medical devices, and electronic financial systems, there is an increasing need for computer systems to be reliable and resilient to failure. Thus, there is an ever growing demand for reliable computing systems. Replicated computers executing identical operations can provide fault tolerance by comparing the outputs of each of the computers and determining which one of the computers may have generated an error during operation. 
     SUMMARY 
     In an embodiment, a method includes assigning, based on a switch module of a particular node of one or more nodes of a fault-tolerant group, a channel to the particular node. The method further includes determining a number of nodes in the fault-tolerant group by exchanging handshake information between the channel assigned to the particular node and channels assigned to other nodes of the fault-tolerant group. The method further includes initializing the fault-tolerant group with the determined number of nodes based on the exchanged handshake information. 
     In an embodiment, determining the number of nodes in the fault-tolerant group is set by one or more switches of the switch module. 
     In an embodiment, exchanging handshake information further includes sending one or more messages from the channel from the particular node to the channel of a second node of the fault tolerant group. The method further includes, if a response to the messages is received at the particular node, marking the channel as active. The method further includes determining the level of fault-tolerance based on the number of nodes in the fault-tolerant group. Determining the level of fault-tolerance may be further based on determining a number of nodes operatively connected to the one or more nodes through the channels marked as active. 
     The method can further include presenting, to a user, the level of fault-tolerance for approval. 
     In an embodiment, determining the number of nodes in the fault-tolerant group includes receiving termination signals along one or more unused channels, and determining the number of nodes in the fault-tolerant group to be the number of nodes that receive signals other than the termination signal. The one or more channels may correspond with ports, and the one or more channels may be in a sequential order. The method may further include providing the one or more termination signals by connecting a termination device to one of the ports. 
     In an embodiment, providing the one or more termination signals may include providing a termination signal at one of the ports, and determining the number of nodes in the fault-tolerant group may include determining the number of nodes corresponding to channels before the termination device in reference to the sequential order of the ports. 
     In an embodiment, providing the termination signals may provide a termination signal at any unused port, and determining the number of nodes in the fault-tolerant group may determine the number of nodes corresponding to channels disconnected from the termination device. 
     In an embodiment, a system includes a fault-tolerant group having one or more nodes. The system further includes a switch module of a particular node of the nodes configured to assign a channel to the particular node. The fault-tolerant group is further configured to automatically self-configure by determining a number of nodes in the fault-tolerant group by exchanging handshake information between the channel assigned to the particular node and channels assigned to other nodes of the fault-tolerant group, and initializing the fault-tolerant group with the determined number of nodes based on the exchanged handshake information. 
     In an embodiment, a non-transitory computer-readable medium is configured to store instructions for a fault-tolerant group. The instructions, when loaded and executed by a processor, causes the processor to assign, based on a switch module of a particular node of one or more nodes of a fault-tolerant group, a channel to the particular node, and automatically self-configure the fault tolerant group by determining a number of nodes in the fault-tolerant group by exchanging handshake information between the channel assigned to the particular node and channels assigned to other nodes of the fault-tolerant group, and initializing the fault-tolerant group with the determined number of nodes based on the exchanged handshake information. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The foregoing will be apparent from the following more particular description of example embodiments of the invention, as illustrated in the accompanying drawings in which like reference characters refer to the same parts throughout the different views. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating embodiments of the present invention. 
         FIG. 1A  is a diagram illustrating an example embodiment of the present invention. 
         FIG. 1B  is a diagram illustrating an example embodiment of the fault-tolerant operational group. 
         FIG. 1C  is a diagram illustrating an example embodiment of a configurable network interface coupled to each node. 
         FIG. 2  is a block diagram of a node employed by an example embodiment of the present invention. 
         FIG. 3  is a diagram illustrating an example embodiment of a quad using the configurable interface of the present invention. 
         FIG. 4  is a diagram illustrating an example embodiment of a duplex using the configurable interface of the present invention. 
         FIG. 5  is a diagram illustrating an example embodiment of a duplex and termination devices using the configurable interface of the present invention. 
         FIG. 6  is a diagram illustrating an example embodiment of a triplex using the configurable interface of the present invention. 
         FIG. 7  is a flow diagram illustrating an example embodiment of a process employed by the present invention. 
         FIG. 8  is a flow diagram illustrating an example embodiment of a process employed by the present invention. 
         FIG. 9  illustrates a computer network or similar digital processing environment in which embodiments of the present invention may be implemented. 
         FIG. 10  is a diagram of an example internal structure of a computer (e.g., client processor/device or server computers) in the computer system of  FIG. 9 . 
     
    
    
     DETAILED DESCRIPTION 
     A description of example embodiments of the invention follows. 
     Previous methods of implementing fault-tolerance employ nodes that are directly connected to each other. Each node independently performs the same function, and for each operation, results are compared and voted on by the other system. In voting, when there is a difference in the results, a failure can be overridden by the correctly calculated answer found by a majority of the nodes, or if there is not a majority, failure can be flagged. These previous methods of implementing fault-tolerance require reprogramming of the nodes making up the fault-tolerant operational group to implement the desired level of fault-tolerance. 
     In general, fault-tolerant operational groups are referred to by the number of backup systems employed. For example, a simplex is an operational group with one node, and a duplex is an operational group with two nodes. Both simplex and duplex operational groups are zero-fault-tolerant. A simplex does not have another node to check results against, and while a duplex can check each node against each other, in the case of a fault, the nodes cannot agree on which node is correct. However, the duplex can note the error, and other corrective actions can be taken, such as cancelling a launch or other operation. A one-fault-tolerant operational group is a triplex, which has three nodes. A two-fault-tolerant operational group is a quad, or quadraplex. In general, the number of nodes in an operational group is given by the formula m=n+2, where m is the number of nodes and n is the desired level of tolerance. A person of ordinary skill in the art can envision higher level fault-tolerant operational groups according to this formula. In these methods, each node was connected to all other nodes directly. For example, a duplex would have two lines—one from the first node to the second, and one from the second to the first. For higher-level fault-tolerant operational groups, however, many more connections are needed. For example, in a triplex, six wires are needed. In a quad, 12 wires are needed. A similar system is described in U.S. Pat. No. 8,972,772, “System and Method for Duplexed Replicated Computing,” by Beilin et al. (hereinafter “the &#39;772 Patent”), which is herein incorporated in reference in its entirety. 
     However, when nodes of a fault-tolerant operational group have to be reprogrammed to adjust the level of fault-tolerance within the operational group, systems can include extraneous computer systems. Accordingly, in an embodiment of the present invention, a system, method, and non-transitory computer readable medium are provided for a self-realizing fault-tolerant operational group that auto-configures based on the number of connected nodes. With such a system, components can be designed without a specific level of fault-tolerance. Instead, the fault-tolerance can be abstracted away into the self-realizing layer. Nodes can, therefore, be repurposed as a simplex, a duplex, a triplex, or a quad based on their connections, in an embodiment of the present invention. In this way, nodes are not wasted in over-specified machines, such as four nodes being in a machine that has only zero fault-tolerance. 
       FIG. 1A  is a diagram  100  illustrating an example embodiment of the present invention. A vehicle  102 , such as a plane, automated vehicle, or spacecraft, includes a fault-tolerant operational group  104 . A person of ordinary skill in the art can recognize that the fault-tolerant operational group  104  can be inside of any other fault-tolerant system. The vehicle  102 , like any fault-tolerant system, includes multiple systems assistant with its operation, such as flight computers, GPS systems, and the like. Each of these communicates with each other, and relies on accurate data from the other systems. To this end, each system can be part of a fault-tolerant operational group  104 , that ensures accuracy to a desired level of fault-tolerance. In embodiments of the present invention, each system can be configured to its own level of fault-tolerance. Each system is agnostic to the other vehicle systems  106  level of fault-tolerance, but a correct assigning of fault-tolerance levels ensures correct data flow among the vehicle&#39;s systems, and that the vehicle  102  is fault-tolerant to its desired level. The fault-tolerant operational group includes one or more nodes configured to carry out parallel calculations, compare the calculations, and vote on a correct solution. When a solution is divergent from the other nodes, the node that calculated the divergent solution can be taken out of service, and the correct result can be used in one-fault and two-fault tolerant operational groups. 
     A fault-tolerant operational group  104 , therefore, receives data  108   a - b  from other vehicle systems  106 , and further sends data  108 - cd  to other vehicle systems  106 . The fault-tolerant operational group  104  is not necessarily informed of the fault-tolerance of the other vehicle systems  106 , but assumes the accuracy of the received data  108   a - b . Likewise, the other vehicle systems  106  may be unaware of the fault-tolerance level of the fault-tolerant operational group  104 , but assumes the data  108   c - d  is accurate. 
       FIG. 1B  is a diagram  120  illustrating an example embodiment of the fault-tolerant operational group  104 . The fault-tolerant operational group  104  includes four nodes: Node  1   120   a , Node  2   120   b , Node  3   120   c , and Node  4   120   d . Nodes  1 - 4   120   a - d  are operatively coupled by six two-way communication channels, or alternatively 12 one-way communication channels to form a quad or two-fault tolerant operational group. Each operation performed by the fault-tolerant operational group  104  is performed by Nodes  1 - 4   120   a - d , and the results are compared. The fault-tolerant operational group  104  of  FIG. 1B  may have many as two of the nodes have a fault, and can still present an accurate result with the other two nodes being in agreement. The fault-tolerant operational group  104  receives data in  122  from other vehicle systems  106 , which can trigger operations or be input as data for its operations. After verification, the fault-tolerant operational group outputs data out  124  to the other vehicle systems  106  with a fault-tolerant answer. 
     In previous configurations of fault-tolerant operational groups, each node is designed to communicate with a set number of other nodes. For example, in the quad illustrated in  FIG. 1B , each node  120   a - d  is designed to work only with a quad and be connected to three other machines. The system cannot be downscaled to a triplex, duplex, simplex, or upscaled to a higher level of fault-tolerance. Such a set up can drive up costs of systems needing the same features of the fault-tolerance operational group  104 . For example, a customer building a drone may wish to purchase a fault-tolerant component for the drone, which needs to be one-fault tolerant, and therefore, require a triplex. However, a supplier may build the component only for a two-fault tolerant system that is specified for human flight, in one example. In this example, the customer has to pay additional money for a fourth node that the drone does not need because the customer has to buy the entire quad. In another example, a supplier may build the component for zero fault-tolerance. In this case, a new fault-tolerant operational group needs to be made from scratch, because the zero fault-tolerant operational group cannot be customized to be one-fault tolerant. Therefore, it is desirable to build nodes that can be connected to other nodes at a custom level of fault-tolerance. 
       FIG. 1C  is a diagram  130  illustrating an example embodiment of a configurable network interface  142   a - d  coupled to each node  140   a - d . The configurable network interfaces  142   a - d  allows customized configurations of fault-tolerant operational groups  104 . Instead of the fault-tolerant operational group  104  of  FIGS. 1A-1B  which are configured to only have one level of fault-tolerance, the fault-tolerant operational group  144  of  FIG. 1C  provides a configurable network interface  142   a - d  for each node  140   a - d . The fault-tolerant operational group  144  can have any number of nodes  120   a - d  connected to form any level of fault-tolerant grouping. Other vehicle systems  106  continue to send data in  122  and receive data out  124 , agnostic of the configuration of the configurable network interfaces  142   a - d  of the fault-tolerant operational group  104 . 
       FIG. 2  is a block diagram  200  of a node  202  employed by an example embodiment of the present invention. The node includes, or is operatively coupled to, a configurable network interface  210 . The configurable network interface includes a plurality of input ports  206   a - c  and output ports  204   a - c . The ports can be standards such as RJ-45, optical ports, or any other communication port. Each node further includes a switch bank  208 . The switch bank  208  includes switches that can indicate either (a) how many nodes are in the fault-tolerant operational group and (b) a channel assigned to the node. For example, in a system allowing up to two-fault tolerance, and therefore, a quad, two switches are needed for determining the number of nodes necessary (e.g., log 2 (number of desired nodes)), and two switches are needed to determine the channel (e.g., log 2 (number of desired nodes)). 
     Each respective input port  206   a - c  and output port  204   a - c  are assigned to specific nodes. In particular, input ports  206   a - c  and output ports  204   a - c  are labeled so that a person configuring the fault-tolerant operational group can ensure the same node is corrected to the correct ports for input and output. In an embodiment, the ports can be color coded to assist designers in connecting nodes correctly. 
       FIG. 3  is a diagram  300  illustrating an example embodiment of a quad using the configurable interface of the present invention. Each node (e.g., Node A  302 , Node B  312 , Node C  322 , and Node D  332 ) is operatively coupled to each of the respective other nodes. An initialization method can confirm that each node is connected and operating, and the fault-tolerant operational group including the nodes (e.g., Node A  302 , Node B  312 , Node C  322 , and Node D  332 ) can then self-realize that it is a quad. Each switch bank also self-identifies its channel. For example, the switch bank  308  of Node A  302  identifies as the first channel, 0 0, the switch bank  318  of Node B  312  identifies as the second channel 0 1, the switch bank  328  of Node C  322  identifies as the third channel 1 0, and the switch bank  338  of Node D  332  identifies as the fourth channel 1 1. 
     In an optional embodiment, the switch banks can assist with the self-configuration of level of fault-tolerance. For example, the fault-tolerance level of the switch banks  308 ,  318 ,  328 , and  338 , having two switches, can be a simplex (e.g., 0 0), a duplex (e.g., 0 1), a triplex (e.g., 1 0), or a quad (e.g., 1 1). However, because of the configurable network interfaces  310 ,  320 ,  330  and  340 , the system can be configured to other fault-tolerances, with fewer machines. 
     Accordingly, in another embodiment, the switch bank(s)  308 ,  318 ,  328 , and  338  can be removed, where channel identification is assigned by firmware, by loading a channel identification stored in memory, or by a hard wiring the signals on the backplane (e.g., via a resistor to ground, short to ground, resistor to voltage, or a short to voltage) or the node itself (e.g., via a resistor to ground, short to ground, resistor to voltage, or a short to voltage). In such an embodiment, the nodes can self-configure the level of fault-tolerance without using the switch banks, and such, the system can operate without the switch banks. A switch module can perform the above described function of the switch bank(s)  308 ,  318 ,  328 , and  338 , or assign channel identification via firmware, load channel identification stored in a memory, or determine channel identification through hard wired signals on the backplane (e.g., via a resistor to ground, short to ground, resistor to voltage, or a short to voltage) or the node itself (e.g., via a resistor to ground, short to ground, resistor to voltage, or a short to voltage). 
     The initialization sequence at a particular node sends several test messages to each other node and verifies a working communication channel from the particular node to each other node by receiving successful acknowledgements of the test messages. If all lines are active, the system can self-realize as a quad. If one of the nodes is not properly communicating, then the system can self-realize without that node. For example, if Node D  332  is not functioning properly and does not respond to the test messages in the expected manner, Node D is excluded from the formed fault-tolerant operational group. 
     In addition, a person of ordinary skill in the art can configure each node with two-way communication wires, such that six wires, instead of the  12  shown in  FIG. 3 , are used in the case of a quad. 
       FIG. 4  is a diagram  400  illustrating an example embodiment of a duplex using the configurable interface of the present invention. The same Node A  302  and Node B  312  can be used to form a duplex, instead of the quad shown in  FIG. 3 . In relation to  FIG. 4 , Node A  302  and Node B  312  are the same nodes with the same respective configurable network interfaces  310  and  320 . However, the only change is that the wires connecting the other devices are removed, and the switch bank  308  and  318  settings are changed. The switch bank, in an embodiment, is set to a duplex (e.g., 0 1), but each channel assignment can be set to be the same as the quad configuration, above. 
     In an embodiment, the nodes search for other nodes in a sequential order. In this embodiment, nodes are expected to be connected from the lowest numbered port channel to the highest. In this embodiment, the initialization sequence can terminate searching for additional nodes after receiving the termination signal because the expectation is that after any empty port, either without the termination signal or with it, that there are no more active nodes. After reaching an empty port, the nodes stop searching for additional ports, in this embodiment. 
     In another embodiment, the nodes confirm connections on all ports. In this embodiment, each node sends out messages on all ports. Nodes that have sent and received acknowledgements by all other nodes are considered an active node of the fault-tolerant group. Nodes that have not sent and received acknowledgements by all other groups are considered non-existent, connected improperly, or non-existent, and are not considered part of the fault-tolerant group. 
       FIG. 5  is a diagram  500  illustrating an example embodiment of a duplex and termination devices using the configurable interface of the present invention. While the system of  FIG. 4  can auto-determine that the outputs  304   c - d ,  314   c - d , and inputs  306   c - d  and  316   c - d  are not connected to a device, a termination device  520   a  can provide a signal to the respective node  302 ,  312  that sends a signal indicating the particular port is not active. In an embodiment, the nodes search for other nodes in a sequential order. In this embodiment, nodes are expected to be connected from the lowest numbered port channel to the highest. In this embodiment, the initialization sequence can terminate searching for additional nodes after receiving the termination signal because the expectation is that after any empty port, either without the termination signal or with it, that there are no more active nodes. 
     In another embodiment, the nodes confirm connections on all ports. In this embodiment, each node sends out messages on all ports. Nodes that have sent and received acknowledgements by all other nodes are considered an active node of the fault-tolerant group. Nodes that have not sent and received acknowledgements by all other groups are considered non-existent, connected improperly, or non-existent, and are not considered part of the fault-tolerant group. In other words, in this embodiment, nodes check for other nodes in ports after receiving a termination signal. 
     The termination devices  520   a - d  also serve a secondary purpose by blocking dirt and debris from collecting in the unused ports. Therefore, the termination devices  520  can be connected in all unused ports to preserve the life of the ports. In further embodiments, the termination devices  520  are enabled to perform foreign object detection (FOD) as well. 
       FIG. 6  is a diagram  600  illustrating an example embodiment of a triplex using the configurable interface of the present invention. While the four nodes  302 ,  312 ,  322 , and  332  shown in  FIG. 3  are shown in  FIG. 6 , several connectors are missing. For example Node D  332  receives no output signals from Node A  302 , Node B  312 , or Node C  322 , and Node D  332  does not output to Node B  312 . Therefore, assuming all nodes are operating correctly internally, Nodes A-C  302 ,  312 , and  322  form a triplex, where Node D  332  is excluded from the self-forming fault-tolerant operational group. 
       FIG. 7  is a flow diagram  700  illustrating an example embodiment of a process employed by the present invention. The &#39;772 patent describes forming a Quad, Triplex, and Duplex, but not Simplex; however, in the &#39;772 patent, the nodes are not provided pre-information as to which level of fault-tolerance to expect from the operational group. The process illustrated by the diagram  700  of embodiments of the present invention, determines, via node to node communication, which nodes are healthy, and thereby form the fault-tolerant operational group. In other words, if only three of four nodes are healthy, a triplex is formed. To efficiently accommodate a modular design, each node is provided pre-information as to what kind of configuration is expected (e.g., from the switch banks described above). However, if the pre-information provided indicates that a triplex is to be formed, and the third node is not operating or communicating correctly, then a duplex is formed. On the other hand, if the pre-information provided indicates that a triplex is to be formed, and a fourth node is connected, a triplex is still formed. The fourth node is ignored, and a quad is not formed. In other words, the pre-information overrides the node network setup when the amount of nodes is greater than the amount of nodes indicated in the pre-information, but the pre-information is overridden when the amount of nodes is fewer than the amount of nodes indicated in the pre-information. 
     After power or reset, the process illustrated in flow diagram  700  begins. The process is an initialization sequence that verifies communication and correct operation with another node. First, a node begins the fault-tolerant operational group initialization ( 702 ). The initialization can be done concurrently at other nodes, or in sequence. The initialization can be begun by a power-on reset circuit. The power-on reset circuit is configured to have a “low” signal (binary 0), and then release an on signal upon initialization. A person of ordinary skill in the art can recognize that different types of signals can be employed, but that whichever type of signal is employed, the initialization is triggered by a change in that signal. 
     Upon power on, a hardware signal is generated in a node when it receives the reset signal. Before this signal, the node operates in an off state (e.g., State 0), but leaves the off state when the reset signal is received. After the reset signal, each node initializes itself through several states. For example, it reads the configuration bits, such as which channel the node is configured to be, and the type of intended operational group. After initializing itself, it begins a loop communicating with other nodes to self-realize the fault-tolerant operational group. 
     The node beginning the initialization, which is referred to as Node A in this example, selects a second node, which is referred to as Node B in this example, to send a message to ( 704 ). The respective communication drivers of Node A and Node B enter into a phase locked loop (PLL). Each node is aware when its clock is being set, and when data is being sent. Each Node, further, includes a fault-tolerant clock (FTC), such that each node&#39;s clock is synchronized within a degree of tolerance. Multiple messages can also be sent (e.g., a multicast or a broadcast). In such a case, after the messages are sent to all nodes in the operational group, the sending node (e.g., Node A) checks for acknowledgments from the other nodes sequentially (e.g., Node B, Node C, and Node D). A person of ordinary skill in the art could also configure the system to check for acknowledgements in parallel. Once Node A realizes that it can communicate with Node B, it can begin confirming communication with another node. 
     In response to receiving the message, Node B sends Node A an acknowledgement. If the acknowledgment is received ( 705 ), Node A analyzes the acknowledgement ( 706 ) and confirms communication from node to second node is operational ( 708 ). A person of ordinary skill in the art can recognize that multiple messages and multiple acknowledgments can be sent and received for each node to increase the confidence the nodes and communication channels are operational. 
     This process can then repeats with other nodes sending out messages in a similar manner to the rest of the fault-tolerant operational group. Once all nodes are confirmed to be connected to each other, the fault-tolerant operational group begins running. 
       FIG. 8  is a flow diagram  800  illustrating an example embodiment of a process employed by the present invention. The method first assigns, based on a switch module of a particular node of one or more nodes of a fault-tolerant group, a channel to the particular node ( 802 ). In relation to  FIG. 3 , the switch module can perform the above described function of the switch bank(s)  308 ,  318 ,  328 , and  338 , or assign channel identification via firmware, load channel identification stored in a memory, or determine channel identification through hard wired signals on the backplane (e.g., via a resistor to ground, short to ground, resistor to voltage, or a short to voltage) or the node itself (e.g., via a resistor to ground, short to ground, resistor to voltage, or a short to voltage). In relation to  FIG. 8 , the method determines a number of nodes in the fault-tolerant group by exchanging handshake information between the channel assigned to the particular node and channels assigned to other nodes of the fault-tolerant group ( 804 ). Exchanging handshake information is further described above in relation to  FIG. 7 . In relation to  FIG. 8 , the method initializes the fault-tolerant group with the determined number of nodes based on the exchanged handshake information ( 806 ). 
       FIG. 9  illustrates a computer network or similar digital processing environment in which embodiments of the present invention may be implemented. 
     Client computer(s)/devices  50  and server computer(s)  60  provide processing, storage, and input/output devices executing application programs and the like. The client computer(s)/devices  50  can also be linked through communications network  70  to other computing devices, including other client devices/processes  50  and server computer(s)  60 . The communications network  70  can be part of a remote access network, a global network (e.g., the Internet), a worldwide collection of computers, local area or wide area networks, and gateways that currently use respective protocols (TCP/IP, Bluetooth®, a registered trademark of Bluetooth SIG, Inc., etc.) to communicate with one another. Other electronic device/computer network architectures are suitable. 
       FIG. 10  is a diagram of an example internal structure of a computer (e.g., client processor/device  50  or server computers  60 ) in the computer system of  FIG. 9 . Each computer  50 ,  60  contains a system bus  79 , where a bus is a set of hardware lines used for data transfer among the components of a computer or processing system. The system bus  79  is essentially a shared conduit that connects different elements of a computer system (e.g., processor, disk storage, memory, input/output ports, network ports, etc.) that enables the transfer of information between the elements. Attached to the system bus  79  is an I/O device interface  82  for connecting various input and output devices (e.g., keyboard, mouse, displays, printers, speakers, etc.) to the computer  50 ,  60 . A network interface  86  allows the computer to connect to various other devices attached to a network (e.g., network  70  of  FIG. 9 ). Memory  90  provides volatile storage for computer software instructions  92  and data  94  used to implement an embodiment of the present invention (e.g., terminator device, fault-tolerant operational block, and node code detailed above). Disk storage  95  provides non-volatile storage for computer software instructions  92  and data  94  used to implement an embodiment of the present invention. A central processor unit  84  is also attached to the system bus  79  and provides for the execution of computer instructions. 
     In one embodiment, the processor routines  92  and data  94  are a computer program product (generally referenced  92 ), including a non-transitory computer-readable medium (e.g., a removable storage medium such as one or more DVD-ROM&#39;s, CD-ROM&#39;s, diskettes, tapes, etc.) that provides at least a portion of the software instructions for the invention system. The computer program product  92  can be installed by any suitable software installation procedure, as is well known in the art. In another embodiment, at least a portion of the software instructions may also be downloaded over a cable communication and/or wireless connection. In other embodiments, the invention programs are a computer program propagated signal product embodied on a propagated signal on a propagation medium (e.g., a radio wave, an infrared wave, a laser wave, a sound wave, or an electrical wave propagated over a global network such as the Internet, or other network(s)). Such carrier medium or signals may be employed to provide at least a portion of the software instructions for the present invention routines/program  92 . 
     The teachings of all patents, published applications and references cited herein are incorporated by reference in their entirety. 
     While this invention has been particularly shown and described with references to example embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the invention encompassed by the appended claims.