Abstract:
A method for producing a metered tape and an indicium on a meter tape comprising determining a location on the meter tape where the indicium is to be printed, generating the indicium with information related to the location incorporated therein, and printing the indicium on the meter tape at the location. A method of authenticating an indicium printed on a meter tape comprising retrieving information stored within the indicium, the information identifying a first location where the indicium is supposed to be positioned relative to the meter tape, detecting a spatial indicator identifying a second location where the indicium is actually positioned relative to the meter tape, and comparing the first location to the second location. Mail metering and authenticating systems for implementing the methods are also disclosed.

Description:
FIELD OF THE INVENTION 
   The invention disclosed herein relates generally to mail metering systems, and more particularly to generating and authenticating a fraud-resistant postage indicium for a mail piece. 
   BACKGROUND OF THE INVENTION 
   Currently, one can send a mailpiece (e.g., letter, package, etc.) through the United States Postal Service (hereafter referred to as USPS) using a postage indicium as evidence of postage payment. The sender may employ a postage meter certified by the USPS (or the postal service of another country) to generate the indicium. The indicium is generally printed on a meter tape (which is later attached to the mailpiece) or directly onto the mailpiece itself, using a printer associated with the postage meter, which may be, for example, an inkjet printer, a thermal transfer printer, or a laser printer. The indicium can subsequently be authenticated by the USPS. For example, an optical scanning device may be used to read the indicium and a verification algorithm may be used to verify the authenticity of the indicium (e.g., by decoding and interpreting information contained within the indicium). 
   As is known, a number of different postal indicia are specified by and permitted by the USPS. One particular type of indicium is specified in the USPS&#39;s Information Based Indicia Program (IBIP). An IBIP indicium includes both a machine readable portion and a human readable portion that may contain (without limitation) information related to the paid postage amount, the issuance date, the postage meter identification number, a postal service symbol, and the class of service. The machine readable portion is typically comprised of a Data Matrix symbology (i.e., a two-dimensional barcode) which may carry cryptographically protected information, such as the postage amount and other postal data that relates to the mailpiece and to the postage meter that prints the indicium. The encrypted information, which is usually referred to as a digital token or a digital signature, is used for authentication purposes. The encryption is also used to protect the integrity of the information, including the postage amount, imprinted on the mailpiece for later verification of postage payment. Since the digital token incorporates encrypted information relating to evidencing of postage payment, altering the printed information in an indicium is detectable by standard authentication procedures. Examples of systems that are capable of generating and printing such indicia are described in U.S. Pat. Nos. 4,725,718, 4,757,537, 4,775,246 and 4,873,645, each assigned to the assignee of the present invention. 
   One security problem that exists with the use of IBIP indicia relates to copying of the indicia for reuse. More specifically, a thief may attempt to re-use an indicium by making copies of an indicium on different pieces of meter tape. The piece(s) of meter tape with the copied indicium is then applied to a mail piece and deposited in the mail, without the thief having paid for the postage. Compounding this problem is the fact that technology has become so advanced that even standard consumer devices, such as photocopiers and printers, are capable of producing credible copies of the indicium (i.e., detection of the copied postage is difficult). 
   Another security problem relates to a single indicium being printed multiple times. For example, a thief may tamper with the postage meter device such that an indicium is printed multiple times (e.g., on different portions of the meter tape, on different mailpieces, etc.) even though the postage amount paid was intended to be associated with a single use. 
   Thus, there exists a need for a mail metering system that can generate indicia with suitable security properties to allow detection of fraudulent use of the indicia. 
   SUMMARY OF THE INVENTION 
   One aspect of the present invention relates to a method for producing a postage indicium on a meter tape including determining a location on the meter tape where the indicium is to be printed, generating the indicium with information related to the location incorporated therein, and printing the indicium on the meter tape at the location. 
   Another aspect of the present invention relates to a mail metering system including a detection device, a processor, and a printing device. The detection device is structured to detect a spatial indicator associated with a meter tape. The processor is in operable communication with the detection device and is adapted to execute a routine to determine a location on the meter tape where an indicium is to be printed and to generate the indicium with information related to the location incorporated therein. The printing device is in operable communication with the processor and is structured to print the indicium on the meter tape at the determined location. 
   Another aspect of the present invention relates to a method of authenticating a postage indicium printed on a meter tape. The method includes retrieving information stored within the indicium, the information identifying a first location where the indicium is supposed to be positioned relative to some initial point on the meter tape, detecting a spatial indicator to identify a second location where the indicium is actually positioned relative to the initial point on the meter tape, and comparing the first location to the second location. 
   Another aspect of the present invention relates to a mail authenticating system including a detection device and a processor. The detection device is structured to detect a spatial indicator and a postage indicium associated with a meter tape. The processor is in operable communication with the detection device. The processor is adapted to execute a routine to retrieve information stored within the indicium, the information identifying a first location where the indicium is supposed to be positioned relative to some initial point on the meter tape, to retrieve information encoded within the spatial indicator, the information identifying a second location where the indicium is actually positioned relative to the initial point on the meter tape, and to compare the first location to the second location. 
   Therefore, it should now be apparent that the invention substantially achieves all the above aspects and advantages. Additional aspects and advantages of the invention will be set forth in the description that follows, and in part will be obvious from the description, or may be learned by practice of the invention. Moreover, the aspects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out in the appended claims. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The accompanying drawings illustrate presently preferred embodiments of the invention, and together with the general description given above and the detailed description given below, serve to explain the principles of the invention. As shown throughout the drawings, like reference numerals designate like or corresponding parts. 
       FIG. 1  is block diagram of a mail metering system according to the present invention. 
       FIG. 2  illustrates a portion of a meter tape used by the mail metering system of  FIG. 1 . 
       FIG. 3  illustrates the portion of meter tape shown in  FIG. 2  with an indicium printed thereon. 
       FIG. 4  is a flow chart illustrating an operational process for creating an indicium according to one embodiment of the present invention. 
       FIG. 5  is a flow chart illustrating an operational process for authenticating an indicium according to one embodiment of the present invention. 
       FIG. 6  illustrates a known mailing label. 
       FIG. 7  illustrates a section of meter tape having an indicium and a logo printed thereon. 
       FIG. 8  illustrates a section of meter tape having an indicium and an advertisement printed thereon. 
       FIG. 9  illustrates a section of meter tape having an indicium and a slogan printed thereon. 
   

   DETAILED DESCRIPTION 
   As employed herein, the term “number” shall mean one or more than one and the singular form of “a”, “an”, and “the” include plural referents unless the context clearly indicates otherwise. 
   An apparatus and method for preventing postage fraud is discussed herein. More specifically, a meter tape having a symbology which identifies specific locations on the meter tape is employed in a mail metering system. The mail metering system detects the symbology, uses the symbology to determine a specific location on the meter tape where an indicium is to be printed, generates an indicium which includes the specific location information encoded therein, and prints the indicium at that specific location on the meter tape. The portion of the meter tape having the indicium is then applied to a mailpiece which is deposited into the mail. Once received, a postal authority may scan the indicium and the symbology from the meter tape that was placed on the mailpiece. The postal authority may then compare the specific location information encoded in the indicium to the actual location of the indicium relative to the symbology to verify that the indicium is authentic. The term location refers to coordinates in one or two dimensions with a margin of error determined by the equipment used to produce the meter tape with the symbology, and the metering equipment used to produce the indicium. It should be noted that while the following description is provided with respect to a mail metering system and authentication system for generating and verifying postage indicia that evidences payment of postage for mail pieces, the present invention is not so limited and can be used with any type of system in which an indicium is generated and printed to verify payment or other types of information. 
     FIG. 1  is a block diagram of a mail metering system  1  according to an exemplary embodiment of the present invention. Mail metering system  1  comprises a detection device, designated generally by the reference numeral  2 , a processor, designated generally by the reference numeral  3 , and a printing device, designated generally by the reference numeral  4 . In the current embodiment, mail metering system  1  is structured to employ a meter tape (not shown in  FIG. 1 ). The meter tape is generally supplied on a continuous roll and fed to the mail metering system  1  which segments the meter tape into various lengths. It should be understood, however, that the meter tape is not limited to tape on a continuous roll, but could also be media provided in sheets, media provided as pre-cut strips, or media with perforations. 
   Detection device  2  is structured to detect any number of markings present on a medium that is examined. For example (and without limitation), detection device  2  is structured to detect one or more spatial indicators associated with the meter tape. As employed herein, the term “spatial indicator” (and all derivatives thereof) refers generally to any symbology which corresponds to and/or identifies unique positions on a medium. For example, a spatial indicator may refer to a symbology which corresponds to one or more coordinates that specify the location of a point, line, area, etc. on a meter tape. Although the preferred embodiment shows a one-dimensional spatial indicator running parallel to the length of the indicium, the orientation of the spatial indicator may be perpendicular to the long side of the indicium. A two-dimensional coordinate of the indicium can be used as an input or an indicium printed on a sheet. An example of a symbology that provides a two-dimensional coordinate to locate a point on a sheet is the symbology as described in U.S. Pat. No. 6,548,768. Detection device  2  can be any conventional detection device such as, for example, a scanner. 
   Processor  3  is in operable communication with detection device  2  and is structured to execute any number of routines for, without limitation, generating and printing postage indicia. For example, processor  3  is structured to execute a routine that is adapted to receive information related to the detection of a spatial indicator on a meter tape; responsive to receipt of that information, to determine a location on the meter tape where an indicium is to be printed (e.g., a location where a particular portion of the indicium is to be located); to generate an indicium which incorporates the determined location information therein; and to cause the printing device  4  to print the indicium on the meter tape at the determined location. It should be noted that processor  3  may execute other routines while remaining within the scope of the present invention. For example, processor  3  is structured to execute routines related to other cryptographic processing of information contained within the indicium. 
   It should be noted that the mail metering system  1  may also include other components, the discussion of which have generally been omitted for clarity. For example, mail metering system  1  may include a number of input devices (not shown) which are in operable communication with processor  3  and which permit a user to interface with the mail metering system  1 . The input devices may include a keyboard, mouse, and/or postage scale, among others. 
   Printing device  4  is in operable communication with the processor  3  and is structured to print the indicia generated by processor  3 . In the exemplary embodiment, for example, printing device  4  is structured to print indicia on the meter tape. More specifically, printing device  4  is structured to print, at a specific location on the meter tape, an indicium which contains encoded location information identifying that specific location. 
   Generally, mail metering system  1  is employed to print postage for a mailpiece. It should be noted that a separate device may be used by a postal authority, for example the USPS, to verify that the postage printed by the mail metering system  1  is authentic by determining whether the indicium is printed in the proper place. This separate device may include a scanner structured to scan the printed postage and symbology on the meter tape and a processor structured to execute a routine adapted to decode the information within the indicium that identifies where the indicium is supposed to be positioned on the meter tape, determine where the indicium is actually positioned on the meter tape, and compare the supposed position of the indicium to the actual position of the indicium on the meter tape. 
     FIG. 2  illustrates a portion of a meter tape  5  according to one embodiment of the present invention. As shown in  FIG. 2 , meter tape  5  has spatial indicator  6  located on a front surface  5   a  thereof. In the current embodiment, spatial indicator  6  includes symbology having a number of blocks  6   a  arranged in a serial fashion, wherein a “filled” block  6   a  represents the binary numeral “1” and an “empty” (or white) block  6   a  represents the binary numeral “0”. The spatial indicator  6  contains sufficient information to ensure that various positions along the meter tape  5  on a roll can be identified (i.e., each portion of meter tape  5  of a given dimension may be uniquely identified with respect to the other portions of meter tape  5  along a given roll). As a result, the spatial indicator  6  allows the mail metering system  1  to easily determine the unique coordinate associated with the location where an indicium is to be printed on the surface  5   a.    
   Although the spatial indicator  6  is discussed in the context of a number of blocks  6   a  arranged in a serial fashion, it should be apparent that other symbologies may be used while remaining within the scope of the present invention. More specifically, the symbology can be any type of one-dimensional code that holds sufficient information to ensure that the various portions along a meter tape may be uniquely identified. For example, PostNet code, OCR, and 4-state barcode symbologies (among others) are contemplated. Meter tape  5  may also incorporate additional security features. For example, meter tape  5  may include forensically verifiable features such as fluorescence, special security inks, a watermark, and/or unusual spacing of the symbology that makes undetectable copying difficult. 
     FIG. 3  illustrates the portion of meter tape  5  shown in  FIG. 2  with an IBIP indicium printed thereon. The indicium includes both machine readable and human readable items. While IBIP indicia are described herein, it should be understood that that is meant to be exemplary only and that other indicia capable of storing location related information as described herein may also be used. More specifically, the indicium shown in  FIG. 3  includes a machine readable Data Matrix two-dimensional barcode  7  and human readable information such as the postage amount  8  for the mailpiece, the date  9  that the indicium was printed, and the identification number  10  of the mail metering system  1  which created the indicium. Typically, the indicium is required by the USPS to be a standard length, for example, two inches long.  FIG. 3  also illustrates the bit stream  23  associated with the given spatial indicator  6 . 
   It should be noted that in the exemplary embodiment, the meter tape  5  is processed by the mail metering device  1  in a serial fashion. For example, the meter tape  5  is passed through the detection device  3  and/or printing device  4  from right to left as illustrated by arrow  24  in  FIG. 3 . Accordingly, the rightmost bits in the bit stream  23  are detected by the detection device  2  before the leftmost bits in the bit stream. It is contemplated that, with minor modifications, an alternative embodiment may permit the direction of travel of the meter tape  5  through the mail metering system  1  to be reversed while still remaining within the scope of the present invention. 
     FIG. 4  is a flow chart illustrating an operational process  12  for creating an indicium according to one embodiment of the present invention. Operational process  12  is initiated when input information related to a mailpiece is received by the mail metering system  1 . For example, when a user places a mailpiece on a postage scale (not shown) and enters the mailpiece address information, service level, etc. using a keyboard (not shown). After the input information is received, a determination is made at operation  13  as to where on the meter tapes the indicium will be printed in relation to the spatial indicator  6 , given the specified dimensions of the indicium (i.e., the length), and in particular where in relation to the spatial indicator  6  the leftmost edge of a particular portion of the indicium, such as the barcode  7 , will be located when printed. 
   In an exemplary embodiment shown in  FIG. 3 , the spatial indicator  6  is based on a linear feedback shift register (LFSR). As is known, an LFSR will result in a predictable and determinable bit stream pattern that will not repeat itself for a very large number of bits. The detection device  2  detects the spatial indicator  6  and determines the first several bits of the bit stream  23  from the origin  6   d  (origin bit) of the current portion of meter tape  5  (e.g., in  FIG. 3  from right to left 0, 1, 0, 0, 1, 1, 1, etc.). Processor  3  then executes a routine which is adapted to employ an LFSR to enable the processor  3  to determine which portion of the meter tape  5  is currently being processed within the mail metering system  1  and to predict a future bit sequence of the spatial indicator  6  on that portion of the meter tape  5 . More specifically, the LFSR enables the processor  3  to determine what the bit stream will be at the location on the meter tape  5  that is the some distance away from the origin  6   d . For example, if (as discussed above) the standard length of the indicium to be printed is two inches, the LFSR enables the processor to predict which bits will be present in the bit stream  23  starting at the origin  6   d  and extending some distance greater than two inches away. As illustrated in  FIG. 3 , the processor  3  is able to determine that bit  6   b  will be located two inches away from the origin  6   d  and that the bit stream will be as shown in  FIG. 3  between  6   d  and  6   b.    
   In the current embodiment, an N-bit LFSR is selected so that the cycle is (2 N −1) bits. As a result, a 32-bit LFSR would repeat after approximately four billion bits, whereas a 64-bit LFSR would not repeat for any reasonable estimate of usage. The LFSR uses an array of N+1 registers R 0 (t) . . . R N (t) and N taps C 1  . . . C N . At each step, R 0 (t) is the output bit. The update for step “t” is R N (t+1)=XOR j=0 . . . N−1  (R j (t) AND C N−j ). For i from 0 to N−1, set R i (t+1)=R i+1 (t) and output R 0 (t). There is no need to parse the output because each bit is the next in sequence generated by the same algorithm. 
   It should be noted that mail metering system  1  in the embodiment of  FIG. 3  has access to the full state of the LFSR and to the meter tape symbology. As a result, prediction of future bits within the bit stream  23 , and thus determination of where the indicium is supposed to be printed, is easily completed. In contrast, a thief only has access to the meter tape symbology (and not the full state of the LFSR), thus making the prediction of future bits much more difficult. 
   Although discussed in conjunction with an LFSR, it should be noted that a routine adapted to employ another algorithm may be employed while remaining within the scope of the present invention. For example, each inch (or other unit of measure) may be labeled using a Fibonacci representation of the distance from the origin  6   d  in inches (or other unit of measure). The Fibonacci sequence is [F 0 , F 1 , . . . ]=[1, 2, 3, 4, 5, . . . F n =F n−1 +F n−2  . . . ]. The Fibonacci representation of a number N is constructed by finding the largest element F n  of the Fibonacci sequence smaller than N. The n th  position in the expansion of the number is set to 1. The procedure is repeated with N−F n  until there is zero remainder. One advantage of using a Fibonacci representation is that it is binary (0&#39;s and 1&#39;s) but there are never two 1&#39;s in-a-row. Thus, two 1&#39;s in-a-row appearing in the bit stream  23  can be used to help parse the stream of bits into locations. The first few natural numbers are represented as [1, 2, 3, 4, 5, 6, 7, 8, 9]=&gt;[1, 10, 100, 101, 1000, 1001, 1010, 10000, 10001]. 
   It should also be noted that the printer  4  may be instructed to randomly advance the meter tape  5  prior to executing operation  13  (i.e., effectively changing the origin  6   d  for that portion of the meter tape). The random advance makes it more difficult for a thief to predict the supposed location of the next indicium when a number of meter tape segments having the same lengths are printed in sequence. 
   Other alternatives may also be used. For example, a random or pseudorandom stream of data may be generated and used; any systematically generated stream of data may be used; and/or a stream of data may be generated using a key such that each sequence in the stream can systematically be checked for authenticity. As yet another example, detection device  2  may be placed at a distance sufficiently upstream of the printing device  4 . Accordingly, the detection device  2  can detect the spatial indicator  6  such that the processor  3  knows the bit stream (i.e., does not need to predict which bits will be seen). Thus, processor  3  can determine which portion of the meter tape  5  is currently being processed within the mail metering system  1 . The processor  3  can generate an indicium incorporating the specific location on the meter tape  5  where the indicium is to be printed. Accordingly, when that portion of the meter tape  5  reaches the downstream printing device  4 , the printing device  4  can print the indicium at that specific location. 
   After the location as to where the indicium will be printed on the meter tape  5  is determined with reference to the spatial indicator  6 , operational control is passed to operation  14  shown in  FIG. 4  where the indicium is generated. The indicium includes location information encoded therein. More specifically, bar code  7  includes therein information identifying the supposed location on meter tape  5  where the indicium is to be printed. In the example illustrated in  FIG. 3 , operation  13  determined that the indicium should begin at the location on the surface  5   a  of the meter tape  5  corresponding with block  6   b  (i.e., the leading edge  7   a  of bar code  7  should be located on the surface  5   a  of meter tape  5  at the position corresponding to block  6   b  which in the current example is two inches from the origin  6   d ). Thus, according to an aspect of the present invention, a portion  11  of the bit stream  23  starting with the bit associated with block  6   b  (such as a 32-bit portion starting with the bit associated with block  6   b  and ending with the bit associated with block  6   c ) may be identified and included in the indicium. More specifically, information identifying the portion  11  of the bit stream  23  may be encrypted and incorporated into the bar code  7 . 
   After the indicium is generated in operation  14 , the indicium is printed on the meter tape  5  in operation  15 . More specifically, printing device  4  prints the indicium at the location on the meter tape  5  that was determined in operation  13 . In the current example, printing device  4  prints the indicium such that the leading edge  7   a  of bar code  7  (which is the beginning of the indicium) is located on the surface  5   a  of meter tape  5  at the position corresponding with block  6   b  (i.e., the starting location as determined in operation  13 ). 
     FIG. 5  is a flow chart illustrating an operational process  16  for authenticating an indicium according to one embodiment. Typically, operational process  16  is executed by a postal authority, such as the USPS. Operational process  16  is initiated when a mailpiece indicium is scanned during the authentication process. In operation  17 , the information stored within the indicium is retrieved. More specifically, the information related to the location on the meter tape  5  where the indicium is supposed to be positioned is retrieved. In the current example, for instance, the information identifying the portion  11  (e.g., a 32-bit portion) of the bit stream  23  is retrieved from bar code  7  and decrypted. 
   Operational control then passes to operation  18  where the spatial indicator  6  on the surface  5   a  of meter tape  5  is detected. In general, the actual location of the indicium is determined in operation  18 . More specifically, in the embodiment shown in  FIG. 3 , the block corresponding to the location on the surface  5   a  of meter tape  5  where the indicium begins (i.e., block  6   b ) and the sequence of bits for a certain number of bits thereafter (e.g., 32) is detected/identified in operation  18 . 
   A determination is made at operation  19  as to whether the supposed location of the indicium (i.e., as retrieved from the indicium in operation  17 ) is the same as the actual location (i.e., as detected in operation  18 ). In the embodiment shown in  FIG. 3 , this is done by comparing the bit stream information obtained in operation  17  to the bit stream information obtained in operation  18 . If the supposed location and the actual location are the same, control branches “YES” and the mailpiece is accepted at operation  20 . If the supposed location and the actual location are not the same, control branches “NO” and the mailpiece is rejected at operation  21 . 
   Unlike stock mailing labels which are of fixed length, the length of the meter tape  5  may vary. As will be shown in  FIGS. 6-9 , additional information such as (and without limitation) logos, advertisements, and slogans which will not fit on a stock mailing label may easily be printed on the meter tape  5 . More specifically,  FIG. 6  illustrates a known mailing label  25  incorporating a unique ID number  26  thereon. The mailing label  25  also has an indicium printed thereon. As discussed above, the indicium is typically required to be a standard length (e.g., 2 inches). As a result, mailing label  25  does not include enough space to print a logo, advertisement, and/or slogan thereon. In contrast, meter tape  5  is typically supplied in a roll such that variable sized sections can be cut to length as needed. For example, the sections of meter tape illustrated in  FIGS. 7-9  (all of which, as discussed above, include symbology for preventing fraud) are of variable length.  FIG. 7  illustrates a section of meter tape  5 ′ having the same indicium as shown in  FIG. 6  plus a logo printed thereon,  FIG. 8  illustrates a section of meter tape  5 ″ having the same indicium as printed in  FIG. 6  plus an advertisement printed thereon, and  FIG. 9  illustrates a section of meter tape  5 ′″ having the same indicium as shown in  FIG. 6  plus a slogan printed thereon. Each section of the meter tape ( 5 ′,  5 ″, and  5 ′″) shown in  FIGS. 7-9  are of different lengths; each being longer than the mailing label  25  shown in  FIG. 6 . Thus, according to the principles of the present invention, a user desiring to print fraud resistant postage also has the ability to add a logo, advertisement, and/or slogan next to their postage indicium. 
   While preferred embodiments of the invention have been described and illustrated above, it should be understood that these are exemplary of the invention and are not to be considered as limiting. Additions, deletions, substitutions, and other modifications can be made without departing from the spirit or scope of the present invention. Accordingly, the invention is not to be considered as limited by the foregoing description but is only limited by the scope of the appended claims.