Abstract:
A fraud detection system within a fuel dispenser includes the ability to measure the amount of fuel dispensed through the fuel dispenser. The measurement is compared to a value independently created representing what the amount of fuel dispensed should approximate. If the values are not comparable, an alarm may be generated to indicate that the fuel dispenser has been modified to perpetrate fraud upon the customers. In particular, a reference used in the comparison is created from data known to contain fraudulent information. If there is a match between the reported profile and the known fraudulent material an alarm may be generated.

Description:
RELATED APPLICATIONS 
     The present application is related to the concurrently filed, commonly invented, commonly assigned application Ser. No. 09/494,825, entitled FUEL DISPENSER FRAUD DETECTION SYSTEM; application Ser. No. 09/494,898, entitled FRAUD DETECTION THROUGH FLOW RATE ANALYSIS; application Ser. No. 09/494,902, entitled FRAUD DETECTION THROUGH TIME ANALYSIS; application Ser. No. 09/495,024, entitled FRAUD DETECTION THROUGH TANK MONITOR ANALYSIS; application Ser. No. 09/495,027, entitled FRAUD DETECTION THROUGH GENERAL INFERENCE; and application Ser. No. 09/494,903, entitled FRAUD DETECTION THROUGH VAPOR RECOVERY ANALYSIS, which are all hereby incorporated by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a scheme for detecting fraudulent activity related to fuel dispensing transactions, and more particularly to a methodology designed to check independently for fraud without relying on a fuel dispensing meter by comparing output from the fuel dispenser or associated elements to known fraudulent data. 
     2. Description of the Related Art 
     Fuel dispensing transactions are a somewhat opaque process to most customers. The customer drives up, makes a fuel grade selection and dispenses fuel into a vehicle or approved container. When the fuel dispenser shuts off, the customer may check the gauge and see that he owes some amount of money for some amount of fuel dispensed. Alternatively, the customer may only have limited funds and may terminate the transaction upon reaching the budgeted amount as displayed on the face of the fuel dispenser. The financial side of the transaction is completed and the customer drives off. 
     Behind the scenes, the fuel dispenser is keeping careful track of the amount of fuel dispensed so that it may be reported to the customer as well as providing a running tally of how much it will cost the customer to purchase the fuel already dispensed. This is typically achieved with a flow meter and a pulser. When a known quantity of fuel has passed through the flow meter, the pulser generates a pulse. Typically, 1000 pulses are generated per gallon of fuel dispensed. The number of pulses may be processed by an internal microprocessor to arrive at an amount of fuel dispensed and a cost associated therewith. These numbers are displayed to the customer to aid him in making fuel dispensing decisions. 
     Customers of fuel dispensers expect honest and accurate calculations of the cost of fuel actually dispensed into their vehicle and rely on the fuel dispenser display to provide the correct figures. However, unscrupulous individuals may, with little effort, modify the pulser and other internal electronics within the fuel dispenser to provide inaccurate readings, in effect, artificially accelerating the perceived rate of fuel dispensing and charging the consumer for fuel that was not actually dispensed. The mechanisms normally responsible for detecting and preventing this sort of fraud are often the mechanisms that are modified or replaced in the process, completely circumventing any fraud prevention device. 
     Thus, there remains a need in the field of fuel dispensing to provide an method to detect fraud within fuel dispensing transactions and provide the appropriate alerts to rectify the situation. 
     SUMMARY OF THE INVENTION 
     The limitations of the prior art are addressed by providing one or more of a matrix of fraud detection schemes that attempt to verify independently of the data reported to the control system the amount of fuel dispensed. If the inferential fuel dispensing observations do not confirm expected fuel dispensing transactions, an alarm may be generated. There are several schemes that could be implemented to detect the fraud according to inferential fuel dispensing observations. 
     The first scheme would be to check the vapor recovery system and determine at what rate the vapor was being recovered. Improved monitors allow accurate determinations of how much vapor has been recovered. If the vapor recovered is not comparable to the amount of fuel allegedly dispensed, then fraud may be present. Furthermore, comparing vapor recovery rates between fuel dispensers may also provide a hint that one or more dispensers have been modified to produce fraudulent transactions. 
     The second scheme includes comparing flow rates between different dispensers. Depending on where the measurement is taken and where the fraud is perpetrated, the flow rate may be higher or lower in the fraudulent dispensers as compared to the nonfraudulent dispensers. However, regardless of where and how, there will be a difference for the fraudulent dispensers. 
     The third scheme includes measuring the time required to dispense fuel at each dispenser. If one dispenser consistently dispenses fuel at time increments different than other fuel dispenser, it may be a modified dispenser perpetrating a fraud on the unsuspecting customer. 
     The fourth scheme includes monitoring for increases or decreases in the flow rate at one dispenser that do not occur at other dispensers at the site. The fuel dispenser that has a different performance profile may have been modified. The changes may occur between transactions or even within a single transaction. 
     The fifth scheme includes using the tank monitor to evaluate how much fuel has been drawn out of the underground storage tank for a given fueling transaction. This can be compared with the amount of fuel that the fuel dispenser reports that it dispensed. If the two numbers are not comparable, then it is likely that the fuel dispenser has been modified. 
     The sixth scheme is actually a variation on the first five schemes combined in that any of the first five schemes could be used, but that instead of comparing the reported value to a source of information which is believed to be uncorrupted, the reported value is compared to a known fraudulent data profile. If the two are similar, then fraud is inferred and an alarm may be generated. 
     Other schemes may also be possible, or the schemes presented herein could be expanded or combined so that the fuel dispenser in question is compared not only to other fuel dispensers at the fueling station, but also to some regional or national average for similar fuel dispensers. This may be particularly appropriate where it is a regional or central office that is attempting to detect the fraud and not a single fueling station. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a typical fuel dispenser designed to dispense fuel from the connected underground storage tank; 
     FIG. 2 is a fueling station employing the fuel dispensers of FIG. 1; 
     FIG. 3 is a schematic drawing of a plurality of fueling stations connected to a central fraud detection computer; 
     FIG. 4 is a flow diagram of the decisional logic associated with a first fraud detection scheme; 
     FIG. 5 is a flow diagram of the decisional logic associated with a second fraud detection scheme; 
     FIG. 6 is a flow diagram of the decisional logic associated with a third fraud detection scheme; and 
     FIG. 7 is a flow diagram of the decisional logic associated with a fourth fraud detection scheme. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The present invention uses a number of different techniques to detect fraud within a fueling transaction. However, a discussion of the physical elements comprising a fuel dispensing environment will be helpful as a background against which the present fraud detection schemes are implemented. 
     Turning now to FIG. 1, a fuel dispenser  10  is adapted to deliver a fuel, such as gasoline or diesel fuel to a vehicle  12  through a delivery hose  14 , and more particularly through a nozzle  16  and spout  18 . The vehicle  12  includes a fill neck and a tank (not shown), which accepts the fuel and provides it through appropriate fluid connections to the engine (not shown) of the vehicle  12 . A display  13  provides a user interface from which the user can determine a cost associated with a particular fueling transaction. While display  13  is preferably a visual display, it may equivalently be an audio user interface, such as might be used by the visually impaired or the like. 
     Flexible delivery hose  14  includes a product delivery line  36  and a vapor return line  34 . Both lines  34  and  36  are fluidly connected to an underground storage tank (UST)  40  through the fuel dispenser  10 . Once in the fuel dispenser  10 , the lines  34  and  36  separate at split  51 . Pump  42 , controlled by motor  44  extracts fuel from the UST  40  and provides it to product delivery line  36 . This can be done by creating a vacuum in line  36  or other equivalent means. Additionally a single pump  42  and motor  44  may serve a plurality of fuel dispensers  10 , or a single fuel dispenser  10 . 
     A vapor recovery system is typically present in the fuel dispenser  10 . During delivery of fuel into the vehicle fuel tank, the incoming fuel displaces air containing fuel vapors. Vapor is recovered from the gas tank of the vehicle  12  through the vapor return line  34  with the assistance of a vapor pump  52 . A motor  53  powers the vapor pump  52 . A control system  50  receives information from a meter  56  and a pulser  58  in the fuel delivery line  36 . Meter  56  measures the fuel being dispensed while the pulser  58  generates a pulse per count of the meter  56 . Typical pulsers  58  generate one thousand (1000) pulses per gallon of fuel dispensed. Control system  50  controls a drive pulse source  55  that in turn controls the motor  53 . The control system  50  may be a microprocessor with an associated memory or the like and also operates to control the various functions of the fuel dispenser including, but not limited to: fuel transaction authorization, fuel grade selection, display and/or audio control. The vapor recovery pump  52  may be a variable speed pump or a constant speed pump with or without a controlled valve (not shown) as is well known in the art. Additionally, the pump  42  and motor  44  may be controlled by the control system  50  directly and provide operating data thereto. 
     Additionally, a vapor flow sensor  54  may be positioned in the vapor return line  34 . Vapor flow sensor  54  may not only sense vapor flow within the vapor return line, but also sense hydrocarbon concentration to provide a total volume of hydrocarbons recovered from the gas tank of the vehicle  12 . In some systems, vapor recovery is dictated by the rate of fuel dispensing, however, in systems equipped with a sensor  54 , vapor recovery operates at least semi-independently of fuel dispensing. 
     To combat fraud in the fuel dispenser  10 , a number of different embodiments of the present invention are offered. These may be implemented in the fuel dispenser  10  or as shown in FIG. 2, in a central fuel station building  62  within a fueling environment  60 . Fueling environment  60  includes the fuel station building  62 , a plurality of fuel dispensers  10 , a central station computer  66 , and a potentially fraudulent dispenser  68 . Dispensers  10  and  68  are fluidly connected to the UST  40 , in which is positioned a UST sensor  64 . UST sensor  64  measures the level of fluid within the UST  40 . Such sensors  64  are well known in the art and can provide extremely accurate measurements of the amount of fuel presently within the UST  40 . They may be float sensors or pressure sensors or the like, but are sensitive enough to detect minute changes in the present volume of fuel within the UST  40 . Most UST sensors  64  are compensated so that the natural expansion and contraction of the fuel according to the vagaries of the atmospheric temperature and pressure are accounted for in the calculation of the volume of fuel present in the UST  40 . 
     Central station computer  66  is communicatively connected to each of the dispensers  10  and  68  as well as UST sensor  64  and is preferably the G-SITE® sold by the assignee of the present invention. Further, central station computer  66  may be connected to each pump  42  and motor  44  within the fueling environment  60 . Thus, central station computer  66  is suited for use in the fraud detection schemes of the present invention. Further, the fueling environments  60  may interconnected one to another and to a corporate headquarters or regional office as seen in FIG.  3 . 
     Specifically, FIG. 3 represents a network  80  that includes a plurality of fueling environments  60 , each with a plurality of fuel dispensers  10  and a central station computer  66 , as well as a central office  82  that includes a central corporate computer  84 . Computers  66  and  84  may be connected by the Internet or other dedicated network  86 , such as a wide area network (WAN) as needed or desired. Central office  82  may be a regional office responsible for fraud detection in a geographic region or a national office responsible for fraud detection throughout the nation. While labeled a corporate computer  84 , it should be appreciated that a franchisee who owns multiple fueling environments  60  could implement the fraud detection system of the present invention at a central office without having more than a nominal corporate nature. Other computers in communication with multiple fueling environments  60  are also intended to be included within the scope of the term “corporate computer” even if they are not tied to a corporate entity. Computers  66  and  84  communicate one to the other as needed or desired and may pass information about fuel dispensers  10  therebetween. 
     Fraud may be perpetrated in a number of ways in a fueling environment  60 . A first type of fraud comprises throttling back the motor  44  and pump  42  while still reporting to the control system  50  that a normal flow rate is passing through the flow meter  56 . For example, normally the pump  42  pumps eight gallons of fuel per minute. Meter  56  registers this flow rate and the pulser makes 8000 pulses per minute. Control system  50  receives these 8000 pulses and reports correctly that eight gallons are dispensed per minute. If the motor  44  is throttled back, it may only pump six gallons of fuel per minute, but the pulser  58  still generates 8000 pulses and the control system  50  believes that eight gallons of fuel are dispensed per minute. There may be other ways to modify the flow of fuel delivery while still convincing the control system  50  that a normal fueling rate is occurring. 
     Alternatively, the pulser  58  could merely be accelerated to generate a greater number of pulses per gallon of fuel that passes through the meter  56 . The control system  50  still believes that 1000 pulses is equivalent to one gallon. For example, eight gallons are dispensed per minute, but the pulser  58  generates 10,000 pulses in that minute, and the control system  50  believes that ten gallon of fuel are dispensed per minute. 
     Note further that the pulser  58  may operate correctly in either situation, but an additional device, which synthesizes the desired, elevated frequency pulse train, may be interposed between the pulser  58  and the control system  50 . Alternatively, the pulser  58  could be operating correctly, but how the control system  50  interpreted the output could be modified. There are other fraudulent schemes that exist as well. The present invention, if properly implemented, may detect most or all of these schemes. 
     Vapor Analysis 
     The first fraud detecting scheme is illustrated in FIG. 4 wherein the fuel dispenser  10 , and particularly the control system  50  receives a fuel dispensing rate from the meter  56  and pulser  58  (block  100 ). Simultaneously, the vapor recovery system recovers vapor (block  102 ). Vapor recovery sensor  54  passes a reading to the control system  50  bearing on the amount of vapor recovered (block  104 ) from which the control system  50  can determine the volume of hydrocarbon vapor recovered during the fueling transaction. By comparing the volume of hydrocarbons recovered to the amount of fuel allegedly dispensed (block  106 ), an inference can be made as to the existence of fraud in the system. 
     In a first aspect of the invention, the control system  50  compares the volume of hydrocarbon vapor recovered to the amount of fuel dispensed (block  106 ). If the volumes are not comparable, or within a certain allowable range (block  108 ), then it may be indicative that the fuel dispenser has been modified to produce fraudulent transactions and an alarm may be generated (block  110 ). This test basically determines that if the fuel dispenser  10  indicates on its display that ten gallons of fuel were dispensed, then an appropriate amount of hydrocarbon vapor should have been recovered. If ten gallons of vapor were recovered, but the concentration or volume of hydrocarbon vapor was too low, that may be indicative that the vapor recovery system is recovering atmospheric vapor, and the actual amount of fuel dispensed was not ten gallons. 
     In a second aspect of the invention, the control system  50  compares the volumetric rate of hydrocarbon vapor recovery to a historical log of volumetric rate of hydrocarbon vapor recovery (block  106 ). If the rates are not comparable or meet some predetermined criterion or criteria (block  108 ) then an alarm may be generated (block  110 ). This test basically determines that if the fuel dispenser  10  indicates that ten gallons of fuel were dispensed, and historically that meant that ten gallons of hydrocarbon vapor were recovered, but that now only eight gallons of hydrocarbon vapor were recovered, that may be indicative that the fuel dispenser  10  has been modified to perpetrate fraud. 
     In a third aspect of the invention, the control system  50  compares the rate of vapor recovery from the beginning of the fueling transaction to the end of the fueling transaction (block  106 ). If the rate dips, or otherwise changes for an inexplicable reason then block  108  is answered negatively, and an alarm may be generated (block  110 ). This test basically determines that if the fuel dispenser  10  was recovering one gallon of hydrocarbon vapor per ten seconds during the first part of the transaction, but later is recovering eight tenths of a gallon of hydrocarbon vapor per ten seconds that there may be a fraudulent transaction occurring. Note that an upward increase could likewise cause an alarm. 
     In a fourth aspect of the invention, the central station computer  66  may compare the rate of vapor recovery to rates of vapor recovery to other fuel dispensers  10  at the fueling environment  60  (block  106 ). If the rates are not comparable (block  108 ), then the computer  66  may infer that there is fraud and generate an alarm (block  110 ). This test basically compares the volumetric rate of hydrocarbon vapor recovery between multiple fuel dispensers  10 . If one fuel dispenser  10  is recovering hydrocarbon vapor more or less efficiently than the other fuel dispensers  10 , then it may have been modified into a fraudulent dispenser  68 . 
     In a fifth aspect of the invention, the corporate computer  84  may compare the rate of hydrocarbon vapor recovery from a particular fueling environment  60 , and perhaps a particular fuel dispenser  10  to a regional or national average hydrocarbon vapor recovery rate as determined by averaging hydrocarbon vapor recovery rates from any number of or all fuel environments  60  communicatively coupled to the corporate computer  84  (block  106 ). It should be appreciated that the average need not be a true average per se, it can be any acceptable statistical model that is representative of a typical hydrocarbon vapor recovery rate. If the measured vapor recovery rate does not meet a predetermined criteria (block  108 ), then an alarm may be generated (block  110 ). This is similar to the fourth aspect, but has a broader base to catch fraudulent dispensers  68 . Whereas the fourth aspect may not catch a fraudulent dispenser  68  if all dispensers  10  have been modified, the fifth aspect probably would catch a fueling environment  60  that had been completely modified to perpetrate fraud. 
     Further note that regardless of how the fraud was perpetrated, this method is useful in fraud detection unless the fraud feasor also modified the vapor recovery system. Note also that this technique is well suited for catching consumer perpetrated fraud as well in that as long as the vapor readings and the reported amount of fuel dispensed readings are not within tolerable limits, an alarm may be generated indicating fraud. 
     Flow Rate Analysis 
     A second embodiment is seen in FIG. 5 wherein the flow rate of the fuel being dispensed is compared to an expected flow rate. If the pump  42  has been throttled back, and the pulser  58  is providing inaccurate data to the control system  50 , then the rate per gallon as reported by the pump  42  or motor  44  on average for non-fraudulent transactions should be significantly higher than the flow rate exhibited during fraudulent sales. For example, if a non-fraudulent fuel sale of ten gallons is delivered at an average of eight gallons per minute, a fraudulent fuel sale of eight gallons (but presented to the consumer as ten gallons) should exhibit a markedly lower average flow rate, perhaps six gallons per minute as reported by the pump  42 . If however, the pulser  58  has been accelerated without modification to pump  42 , then the control system will show a flow rate that is much higher than the actual flow rate as well as one that appears faster than normal non-fraudulent sales. 
     In a first aspect of this second embodiment, the fuel dispenser  10 , and particularly the meter  56 , reports to the control system  50  a measured flow rate of the fuel presently being dispensed (block  120 ). Control system  50  compares the reported flow rate to a historical flow rate established by the fuel dispenser  10  (block  122 ). If the flow rate fails to meet some criterion or criteria (block  124 ) then an alarm may be generated (block  126 ). Note that for a given fuel dispenser  10 , the average flow rate should remain relatively constant from transaction to transaction, thus the historical data would have to be established before any tampering to be effective. This could be done during factory calibration or immediately after installation to reduce the risk of the historical data being fraudulent from the outset. However, if the historical data is accurate, any change or deviation therefrom may be indicative of tampering. 
     In a second aspect of this embodiment, the fuel dispenser  10  measures the flow rate of the fuel presently being dispensed (block  120 ). This is reported to the central station computer  66 , which then compares the reported flow to an average flow rate for all the fuel dispensers  10  within the fueling environment  60  (block  122 ). If the flow rate fails to meet some criterion or criteria (block  124 ) then an alarm may be generated (block  126 ). This aspect is effective when only a few of the fuel dispensers  68  have been corrupted within a given fueling environment  60 . These fuel dispensers  68  will show different average fueling rates from the fuel dispensers  10  which have not been corrupted, and the appropriate alarm may be generated. 
     In a third aspect of this embodiment, each fuel dispenser  10  measures an average flow rate of fuel presently being dispensed (block  120 ) and reports to the central station computer  66 . Central station computer  66  periodically reports the average flow rates for each fuel dispenser  10  within the fueling environment  60  to the central corporate computer  84 . Corporate computer  84  then compares the reported average flow rates to an average established by some or all of the fuel dispensers  10  that provide reports to the computer  84 , either directly or indirectly. This aspect is particularly useful in catching fueling environments  60  in which every fuel dispenser  68  has been corrupted. To reduce the load on the network  86 , the average fueling rates may be reported periodically rather than during every fueling transaction. This should be automated and have as little chance as possible for human intervention, otherwise, data tampering may occur, reducing the likelihood that the fraud is detected. 
     In a fourth aspect of this embodiment, the average flow rate is compared to a maximum allowable flow rate of which the fuel dispenser  10  is capable. For example, some fuel dispensers  10  have a maximum flow rate of ten gallons per minute. If the fuel dispenser  10  indicates that it is delivering twelve gallons per minute, it is likely that the fuel dispenser  10  has been corrupted or modified. 
     In a fifth aspect of this embodiment, pump  42  or motor  44  reports to the control system  50  at what rate fuel is being removed from the UST  40  to provide the flow rate of the fuel being dispensed (block  120 ). This value is compared to the amount the control system  50  believes is being dispensed (block  122 ). Control system  50  determines if the values compared meet some predetermined criterion or criteria (block  124 ). If they do not, an alarm may be generated (block  126 ). 
     In a sixth aspect of this embodiment, the pump  42  or the motor  44  reports the speed at which fuel is being removed from the UST  40  to the central station computer  66  (block  120 ). Central station computer  66  also receives from the control system  50  the amount of fuel that the control system  50  was told had been dispensed. From these two values, the central station computer  66  can make the desired comparison (block  122 ). If the two values are not comparable or otherwise fail to meet some predetermined criterion or criteria (block  124 ) an alarm may be generated (block  126 ). 
     In a seventh aspect of this embodiment, the pump  42  or the motor  44  reports the speed at which fuel is being removed from the UST  40  to the corporate computer  84  (block  120 ), which makes the comparison (block  122 ) and generates an alarm (block  126 ) if some criterion or criteria are not met (block  124 ). 
     In an eighth aspect of this embodiment, the pump  42  or the motor  44  reports the speed at which fuel is being removed from the UST  40  to the central station computer  66  (block  120 ). Central station computer  66  compares the rate of fuel flow at that particular dispenser  10  to the average fuel flow rates at other dispensers  10  within the fueling environment  60  (block  122 ). If the flow rate in question does not meet some predetermined criterion or criteria (block  124 ) then an alarm may be generated (block  126 ). 
     In a ninth aspect of this embodiment, the pump  42  or the motor  44  reports the speed at which fuel is being removed from the UST  40  to the corporate computer  84  (block  120 ). Corporate computer  84  compares the flow rate to an average flow rate as established by the flow rates reported from a plurality of fueling environments  60  (block  122 ). If the measured value does not meet some predetermined criterion or criteria (block  124 ) an alarm may be generated. 
     In a tenth aspect of this embodiment, the central station computer  66  generates an average measured flow rate from the various pumps  42  or motors  44  within the fueling environment (block  120 ) and reports this average to the corporate computer  84 . Corporate computer  84  then compares the average flow rate for a particular fueling environment against an average flow rate for comparably situated fueling environments (block  122 ). If the reported average flow rate does not meet some predetermined criterion or criteria (block  124 ) an alarm may be generated. 
     In an eleventh aspect of the present invention, the flow rate of the dispenser  10  is measured and compared to other flow rates measured during the same fueling transaction. If the flow rates vary past certain allowable parameters within a single transaction, this may be indicative of fraud, and an alarm may be generated. The comparison can be done by the control system  50 , the central station computer  66 , or even the corporate computer  84  as needed or desired. 
     Note that for the analysis to be the most probative, the make and model of the fuel dispensers  10  being compared are preferably the same. It may be meaningless to compare model X to model Y if they are designed to have different fueling rates. However, different models may be designed to have identical fueling rates and in such a circumstance, the comparison may still be probative. 
     Time Required Analysis 
     A third embodiment is seen in FIG.  6  and is closely related to the second embodiment. However, in contrast to the second embodiment, the total time required for the fueling transaction is measured and compared to times required for similar fueling transactions. 
     A first aspect of this embodiment measures the time required for the fueling transaction (block  130 ). Control system  50  and an internal timer or the like may accomplish this measurement. At the same time, the meter  56  and the pulser  58  provide a measurement of the amount of fuel dispensed to the control system  50  (block  132 ). Control system  50  then compares the amount of time required to dispense the measured amount of fuel to a historical collection of data (block  134 ). If the measured values fail to meet some criterion or criteria (block  136 ) an alarm may be generated (block  138 ). For example, the fuel dispenser  10  may know that it should take seventy-two seconds to dispense twelve gallons based on the historical data. If the present fuel transaction purports to dispense twelve gallons in sixty seconds, then there is an indication of fraud. 
     A second aspect of this embodiment has an external time measuring device  70 , such as a camera with a timer (FIG. 2) measure the time required for a fueling transaction (block  130 ). The control system  50  still gathers a measurement indicative of the amount of fuel allegedly dispensed (block  132 ). The central station computer  66  then compares the time required to the fuel dispensed (block  134 ). If the results do not meet some predetermined criterion (block  136 ), an alarm maybe generated (block  138 ). This requires the fraudulent actor to modify not only the fuel dispenser  68 , but also the time measuring device  70  if he is going to perpetrate the fraud, increasing the likelihood of observation or detection. Note also that the time measuring device  70  could report directly to the control system  50 , and control system  50  perform the comparison. 
     A third aspect of this embodiment uses the central station computer  66  to provide the ability to measure the time required to complete a fueling transaction (block  130 ). Fuel dispenser  10  and specifically control system  50  measure the amount of fuel allegedly dispensed (block  132 ). The central station computer  66  compares the time required to the fuel dispensed (block  134 ). If the results do not meet some predetermined criterion (block  136 ), an alarm may be generated (block  138 ). Again, this requires modifications at two locations for the fraudulent actor, thereby increasing the likelihood of apprehension. 
     A fourth aspect would be identical to the third aspect, but the corporate computer  84  would provide the time measuring function. This is not preferred because of the computational requirements placed on the corporate computer  84  and the loads placed on the network  86 , but it could be implemented if desired. 
     A fifth aspect of this embodiment has the central station computer  66  collect and average the time required for fueling transactions (block  130 ) as well as the average amount of fuel dispensed (block  132 ) and pass this to the corporate computer  84 . The corporate computer  84  compares these averages to predetermined averages (block  134 ) for these activities. If the reported values do not meet some predetermined criterion or criteria (block  136 ) an alarm may be generated (block  138 ). 
     This third embodiment is essentially a modification of the average fueling rate embodiment in that a number of gallons delivered are being compared with a time required. However, the actual data that is being compared is slightly different—instead of an average fueling rate, two data points are being compared. The end result is the same, but the implementation may be different. 
     Tank Monitor 
     A fourth embodiment is seen in FIG.  7 . This particular embodiment compares the amount of fuel that the fuel dispenser  10  indicates that it dispensed to the amount of fuel removed from the UST  40 . Note that this embodiment functions best when only one fuel dispenser  10  is draining fuel from UST  40  at a time, and thus it may be difficult to isolate each dispenser  10  under such conditions. However, over a period of time, statistically, such isolated fueling events should occur, providing the fraud detection desired. Alternatively, the station owner/operator or the corporate fraud control agent can periodically perform the tests in controlled situations. 
     In a first aspect of this embodiment, the meter  56  and pulser  58  provide a measurement of the amount of fuel dispensed to the control system  50  (block  140 ). Sensor  64  measures the amount of fuel removed from the UST  40  (block  142 ) and provides this measurement to the control system  50 . Control system  50  then compares the amount of fuel dispensed to the amount of fuel removed (block  144 ). If the comparison does not meet some predetermined criterion or criteria (block  146 ) then an alarm may be generated (block  148 ). 
     In a second aspect of this embodiment, the meter  56  and pulser  58  provide a measurement of the amount of fuel dispensed to the central station computer  66  (block  140 ). Sensor  64  provides a measurement of the amount of fuel removed from UST  40  to the central station computer  66  (block  142 ). Central station computer  66  then compares the amount of fuel dispensed to the amount of fuel removed (block  144 ). If the comparison does not meet some predetermined criterion (block  146 ) then an alarm may be generated (block  148 ). 
     In a third aspect of this embodiment, the measurements of blocks  140  and  142  could be provided to the corporate computer  84  and the comparison performed remotely from the fueling environment  60 . 
     In a fourth aspect of this embodiment, the central computer station  66  could collect an average sensor  64  reading per transaction to the corporate computer  84  (block  142 ) and the corporate computer  84  could then perform the comparison (block  144 ). If the station average did not meet some predetermined criterion or criteria (block  146 ) then an alarm could be generated. 
     Sensor  64  is sensitive enough that even the occurrence of a single “short deliver” of 20% may be detectable for a ten or fifteen gallon delivery. Additionally, while it is preferred that this to comparison occur during times when only a single fuel dispenser  10  is draining fuel from UST  40 , it is possible to attempt the comparison when two or more fuel dispensers are operating. The fact that an anomalous result occurs indicates that one or more of the fuel dispensers  10  that drained fuel from UST  40  when the anomalous result occurred are potentially fraudulent. Repeated events could isolate the questionable fuel dispenser  68 , or the anomalous result may trigger a manual inspection of the various fuel dispensers  10  until the problem is located. 
     Compare to Known Fraudulent Data 
     This embodiment is somewhat akin to any and all of the above embodiments. However, instead of comparing the reported values to a known acceptable value, the reported values could be compared to a known fraudulent value. Thus, all of the above processes could be repeated, but in the comparison to the predetermined reference, the predetermined reference would be a known fraudulent data point. If the two values were identical or within some predetermined confidence interval, an alarm could be generated indicating that the tested dispenser  68  was fraudulent, the tested fueling environment  60  was fraudulent or the like, depending on exactly what had been tested. 
     It should be noted that these solutions are not mutually exclusive, a plurality of such solutions could be implemented. Different aspects of the same embodiment could be implemented simultaneously or different embodiments could be combined to greatly increase the likelihood that fraud is detected and corrected. This will increase consumer confidence and protect the goodwill of the companies responsible for selling fuel from the illegal activities of rogue franchisees. Further, while the tests enunciated above speak in terms of the measured values not meeting some predetermined criterion or criteria, it should be appreciated that the converse is true. Instead of failing a test which indicates that the fuel dispenser  10  is normal, an alarm could be generated when the fuel dispenser  10  passes a test that indicates fraud. Both are equivalent and effectively report the same information, but are phrased slightly differently and perhaps implemented differently. 
     Additionally, as would be expected when decisional logic is executed by a computer or the like, the particular implementations may be implemented through software or dedicated memory containing hard wired instructions on how to perform the desired tasks. 
     Further, a failure to report data to a corporate computer  84  may also be indicative of fraud. In such an instance, an alarm should be generated and the station operator interrogated as to why the data was not provided as required. Alternatively, an independent, manual test could be performed at the station unbeknownst to the station operator to confirm that fraudulent activity is taking place before any questions are asked. 
     The present invention may, of course, be carried out in other specific ways than those herein set forth without departing from the spirit and essential characteristics of the invention. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, and all changes coming within the meaning and equivalency range of the appended claims are intended to be embraced therein.