U.S. patent number 3,792,446 [Application Number 05/311,921] was granted by the patent office on 1974-02-12 for remote postage meter resetting method.
This patent grant is currently assigned to Pitney-Bowes, Inc.. Invention is credited to Alton B. Eckert, Jr., Robert B. McFiggins.
| United States Patent |
3,792,446 |
| McFiggins , et al. |
February 12, 1974 |
REMOTE POSTAGE METER RESETTING METHOD
Abstract
A data center equipped with a programmed digital computer and a
voice answer-back unit processes telephone calls from users of
postage meters equipped with combination locks, wherein each lock
inhibits recharging of its associated meter with an additional
postage increment while locked and its combination changes in
random sequence with each actuation to enable meter recharging. The
computer operates via the answer-back unit to voice communicate
with the caller in requesting the input of data uniquely
identifying the caller and the postage meter to be recharged
pursuant to issuing the next combination.
|
Inventors: |
McFiggins; Robert B. (Stamford,
CT), Eckert, Jr.; Alton B. (Norwalk, CT) |
|
Assignee: |
Pitney-Bowes, Inc. (Stamford,
CT)
|
| Family
ID: |
23209078 |
| Appl.
No.: |
05/311,921 |
| Filed: |
December 4, 1972 |
| Current U.S.
Class: |
705/403; 379/111;
379/91.01 |
| Current CPC
Class: |
G06F
3/16 (20130101); G07B 17/00193 (20130101); G07B
17/0008 (20130101); G07B 2017/00233 (20130101); G07B
2017/00096 (20130101); G07B 2017/00161 (20130101) |
| Current International
Class: |
G06F
3/16 (20060101); G07B 17/00 (20060101); G06f
009/18 () |
| Field of
Search: |
;340/172.5,147R,149A,152R ;179/2A,2CA,2DP ;444/1 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Zache; Raulfe B.
Attorney, Agent or Firm: Soltow, Jr.; William D. Scribner;
Albert W. Wittstein; Martin D.
Claims
Having described the invention, what is claimed as new and desired
to secure by Letters Patent is:
1. For use at a data center to process telephonic calls from
remotely located users of postage meters equipped with combination
locks wherein the locks inhibit recharging of their associated
meters with increments of postage while locked and their respective
combinations change in random sequence with each actuation thereof
to permit meter recharging, and wherein the data center is equipped
with a programmed digital computer and a voice answer-back unit,
the method comprising the steps:
A. answering an incoming telephonic call from a postage meter user
to establish two-way communication;
B. formulating via the answer-back unit, a voice response for
transmission to the user requesting the input of data uniquely
identifying the postage meter to be recharged;
C. processing said identification data, upon receipt, to check the
authenticity of the call;
D. determining the next combination capable of actuating the
combination lock adapted to the postage meter to be recharged;
E. updating the user's file held in computer memory to reflect the
fact that the identified postage meter is to be recharged; and
F. transmitting, via the answer-back unit, said next combination to
the user, thereby affording to the user the capability of
recharging the identified postage meter.
2. The method defined in claim 1, wherein the postage meters are
each equipped with ascending and descending registers, which
further includes the steps of:
A. formulating, via the answer-back unit, a voice transmission to
the user requesting the input of the numerical contents of the
ascending and descending registers of the identified postage
meter;
B. summing the contents of the ascending and descending registers,
as entered by the user, and comparing this total with the total of
these register contents held in computer memory as the result of
the previous recharging of the identified postage meter;
C. upon the detection of the equality therebetween, preceeding with
the determination of the next combination; and
D. said updating step including storing in the computer memory the
new contents of the ascending and descending registers as entered
by the user.
3. The method defined in claim 2, wherein the computer memory also
stores the current credit balance of each user's account and the
dollar amount of the increment of postage to which each postage
meter may be recharged upon a single actuation of the combination
lock adapted thereto, which further includes the step of, prior to
proceeding to the determination of the next combination, checking
the credit balance of the user's account to determine if sufficient
funds are on deposit to cover the increment of postage requested by
the user.
4. The method defined in claim 2, further comprising the steps of
developing a random sequence of combinations for each combination
lock using a random number generator, and performing new
combination determination steps using a random number generation
algorithm the same as was used in developing the random sequence of
combinations accommodated in each lock.
5. The method defined in claim 4, which further includes the step
of checking to see that the entire random sequence of combinations
accommodated in the identified combination lock has not been issued
to the user.
6. The method defined in claim 2, which further includes, in the
event inequality is detected between the sum of registers entered
by the user and the sum of registers stored in computer memory,
checking to determine if the ascending register of the identified
postage meter overflowed since its previous recharging by comparing
the entered sum of registers total with the sum of the stored
register readings minus ascending register size and, if equality is
then detected, proceeding to the new combination determining
step.
7. The method defined in claim 2, wherein the combination issued on
the previous occasion when the identified postage meter was sought
to be recharged is stored in computer memory, which further
includes in the event inequality is detected between the sum of
registers entered by the user and the sum of registers stored in
computer memory the steps of:
A. checking to determine if the identified postage meter was
actually recharged on that previous occasion on the basis of the
entered and stored register readings and the postage increment by
which the identified postage meter may be recharged, and, if
not;
B. retrieving the stored combination from memory for transmission
to the user without executing said next combination determining
step.
8. The method defined in claim 2, which further includes the steps
of:
A. responding to an input request from the user for a second
postage increment for recharging into the identified postage meter
by requesting the input of the numerical contents of the ascending
register and the descending register with the first postage
increment included therein;
B. again summing the register readings entered by the user and
comparing this total with the total of the previously entered
register readings held in memory;
C. upon the detection of equality therebetween, repeating said next
combination determination, updating, and next combination
transmitting steps, in sequence.
9. The method defined in claim 8, which further includes the step
of determining that the requested postage increment will not
overflow the descending register of the identified postage meter
before preceeding to said next combination determining step.
10. The method defined in claim 8, further comprising the steps of
developing a random sequence of combinations for each combination
lock using a random number generator, and performing a new
combination determination step using a random number generation
algorithm the same as was used in developing the random sequence of
combinations accommodated in each lock.
Description
BACKGROUND OF THE INVENTION
Postage meter resetting or recharging and record keeping operations
are now highly dependent on manual routines by both the Postal
Service and meter users. Post Office employees have to visually
inspect, open, recharge, and reseal the meters, in addition to
filling out several different forms for record keeping purposes.
These tasks will continue to become more expensive as labor rates
rise and as more postage meters come into service. That is, the
effort required to administer the metered mail system will rise in
direct proportion to the number of postage meters in service.
In addition to the time required to recharge postage meters, there
are occasional errors in recharging the meters which are usually
not discovered until the user returns with the meter to his office.
A return trip to the Post Office is then required to obtain the
correct recharging.
Meter recharging is a reasonably complicated process involving
large sums of money. Special training for selected Post Office
personnel is required to recharge the meters and to maintain the
records. This operation must be supervised and special assignments
must be made when the trained personnel are on vacation or are out
sick.
The present record keeping system for postage meters is completely
manually administered. The Postal clerk is required to issue a
receipt which contains all of the meter register readings before
and after the recharging, along with the amount of the postage
increment recharged into the meter. This recharging information is
also entered into the customers "Daily Record of Meter Register
Readings" book and a complete transaction is entered into the Post
Office "Record of Meter Settings" book. Each Post Office is also
required to make a quarterly summation of postage sales for all
customers.
The users of the metered mail system are inconvenienced by the fact
that they must bring their meters to the Post Office for
recharging. The problems associated with such a trip involve
obtaining a check or cash to pay for the additional postage to be
recharged into the meter, actually making the trip, parking and
waiting in line at the Post Office. This takes time and thus costs
the meter user money.
The foregoing is not to say that the metered mail system does not
have significant advantages. Its current wide use is testiment to
the fact that it indeed does have tremendous advantages. The most
widely used metered mail system is based on a postage meter having
the features of double registers (ascending and descending) and
credit balance lockout. With this type of meter, the customer has
complete control of the postage kept in the meter and cannot use
more postage then has been paid for. The Post Office is assured of
payment and does not have to operate a collection department or
consider suspension of services for nonpayment. The recharging
records and procedures provide an excellent record of revenue
collection and cannot easily be defrauded, thus minimizing any
temptation to collusion between a meter user and a Postal
representative to defraud the Government. By virtue of these
advantages, there need be no discrimination made by the Postal
service against a mailer becoming a metered mail user. Moreover,
metered mail does not have to be cancelled, thereby simplifying the
handling of mail by the Post Office.
SUMMARY OF THE INVENTION
In accordance with the present invention, there is provided a
system for overcoming the above-noted drawbacks to the present
metered mail system without sacrificing any of its advantages. This
system is based on the use of a double register, credit balance
lockout, postage meter, except that the meter is equipped with a
combination lock whose combination changes in predetermined random
sequence (termed pseudo-random sequence by mathematicians) each
time it is actuated. This combination lock operates on the
resetting or recharging mechanism of the postage meter such that,
when unlocked, the mechanism may be manipulated to recharge the
meter with an increment of postage. As the meter is recharged, the
combination lock automatically locks itself to prevent subsequent
recharging of the meter unless and until the correct new and
different combination is entered. Combination locks of this type,
suitable for use in the application of the present invention, are
disclosed in U.S. Pat. Nos. 3,034,329 and 3,664,231.
The present invention is specifically directed to an automated
method for issuing the respective new combinations to a plurality
of remotely located postage meter users from a central station over
normal touch-tone telephone equipment. The basic operating
components of the central station are a programmed digital computer
operating in accordance with the present invention and a
conventional voice answer-back unit. The computer answers each
user's telephone call and automatically, via the answer-back unit,
formulates a series of voice instructions requesting the user to
input via the phone keys certain encoded data uniquely identifying
the caller and the meter to be recharged. The computer processes
this input data for authenticity and, when satisfied, automatically
issues, via the voice answer-back unit, the new combination capable
of actuating the caller's combination lock to permit recharging of
the associated meter with an additional increment of postage
without having to remove the meter from its normal location. At the
time of issuing the new combination to a particular user, the
computer automatically updates the user's file or account held in
memory, and may if desired initiate the process of billing the user
for the increment of postage to which he has been given access.
DESCRIPTION OF THE DRAWINGS
For a fuller understanding of the nature and objects of the
invention, reference should be had to the following detailed
description taken in connection with the accompanying drawings, in
which:
FIG. 1 is an overall, generalized block diagram of a system
constructed in accordance with the present invention;
FIG. 2 is a flow diagram illustrating the operation of the data
center of FIG. 1;
FIG. 3 is a flow diagram of a sub-routine for executing the
function of a random number generator for calculating the new
combination issued in the flow diagram of FIG. 2; and
FIG. 4 is a diagrammatic illustration of the manner in which the
sub-routine of FIG. 3 extracts the new combination from the numbers
developed by the random number generator.
DETAILED DESCRIPTION
Referring to FIG. 1, the system of the invention comprises a
plurality of remote stations 10 capable of communicating with a
data center, generally indicated at 12, via telephone exchange
equipment, generally indicated at 14. The transmitter-receiver at
each remote station 10 is a conventional tone signalling telephone
16 for effecting two-way communication with the data center 12. The
data center includes a data set 18 of known construction, such as a
Bell System Model 403 data set, for translating frequency encoded
data inputs from one of the telephones 16 into a suitable machine
language for a programmed or special purpose digital computer 20,
for example, a Data General "Nova." The computer, in turn, controls
a voice answer-back unit 22 of known construction such as a
cognitronics Model 632, to formulate voice responses for
transmission via data set 18 and telephone exchange 14 back to the
particular telephone 16 in communication with the data center 12.
The telephone at each remote station 10 is preferably of the
touch-tone type capable of transmitting frequency encoded numeric
outputs to data center 12. Alternatively, a dial telephone may be
equipped with a touch-tone pad capable of generating frequency
encoded digital data in the same manner as a touch-tone phone.
Also located at each remote station 10 is a postage meter 24 of
known construction, such as a Model 5300 Pitney Bowes meter, having
double register and credit balance lockout features. The two
registers comprise an ascending register, which accumulates the
dollar amount of postage used over the life of the meter and a
descending register, which is incremented with each dollar amount
of pre-paid postage reset into the meter and is decremented as this
increment of postage is used. When the descending register is
decremented to a dollar amount of postage which is less than the
maximum dollar amount of postage capable of being issued by the
meter in a single cycle, the meter automatically locks out to
prevent further usage until recharged. This feature insures that
the user will always have a postage credit balance and is incapable
of operating his meter in a manner such as to create a deficit
situation wherein the Post Office is owed money for postage
used.
The postage meter at each remote station 10 is modified to the
extent that it is equipped with a combination lock 26 operating on
the resetting or recharging mechanism of the postage meter. This
combination lock, in accordance with the invention, has the unique
characteristic of automatically changing its combination each time
it is actuated. When actuated or unlocked, the user is capable of
manipulating a knob 28 to increment the descending register of the
postage meter 24 by a predetermined dollar amount of a postage
increment. This may be accomplished, for example, by a single turn
of knob 28, whereupon lock 26 locks up the recharging mechanism so
that another increment of postage cannot be set into the meter
until the correct new and different combination is entered into the
lock 26 by way of clusters of keys 30 and 32, in the illustrated
embodiment.
As will be seen from the description to follow, the system of FIG.
1 permits remote postage meter resetting or recharging at the meter
site, thus eliminating the necessity of the user having to
transport his meter to the Post Office for recharging with an
additional increment of postage. This remote recharging is
effective using existing communications links, i.e., the telephone
exchange network, from a remote central location without the
requirement for direct signal control on the postage meter itself,
as has been proposed in the past. These prior approaches all
involved drastic revisions of existing postage meter designs so as
to accept a remotely generated and transmitted initiating or
enabling signal for recharging the meter, as well as expensive
communications and terminal equipment. In the remote recharging
system of the present invention, the postage meter 24 need only be
slightly modified so as to accept the adaptation of combination
lock 26.
The manner in which the data center handles an incoming call from a
user at one of the remote stations 10 seeking to recharge his
postage meter 24 is shown in the flow diagram of FIG. 2. When a
user determines that his postage meter needs recharging, he keys in
the telephone number of the data center on his telephone 16. The
data center answers, as indicated at 39, to complete the telephone
connection, and the computer 20 controls the voice answer-back unit
22 to compose a voice response, as indicated by output block 40,
for transmission back to the caller requesting a numeric input
uniquely identifying the caller or the calling remote station 10.
This numeric input request may be for an account number, or the
like, which is also held in computer memory. Computer 20 then
converts to an input mode, illustrated by input block 42, awaiting
receipt of a predetermined number of digits, representing, for
example, the caller's account number. The user then keys in his
account number using the numeric keys on his touch-tone phone 16.
The frequency encoded digit inputs are converted by data set 18 at
the data center 12 into computer language for the computer 20. The
computer then searches its memory to determine if the received
account number is stored therein, as represented by decision block
44. If the computer locates a comparable account number in its
memory, meaning that the received account number is valid, the
program exits decision block 44 on branch 45 to output block
46.
On the other hand, if the computer fails to locate in its memory an
account number comparable to the one received from the caller, the
program exits decision block 44 on branch 47 to a second decision
block 48. Here the computer tests to determine how many chances the
caller has been given to input a valid account number. If the
caller has had less than three attempts to enter a valid account
number, the program exits decision block 48 on branch 49 to output
block 50, wherein the computer controls the voice answer-back unit
22 to formulate a voice transmission back to the caller informing
him, in effect, that his entry was not valid and to please reenter
his account number. The program, as indicated by branch 51, reverts
back to the input of block 42 wherein the computer is again
conditioned to accept an account number entry. If, on three passes
through decision block 44, the caller has failed to enter a valid
account number, the decision is made that the call being processed
is probably spurious and the program exits decision block 48 on
branch 53 pursuant to breaking the telephone connection with the
caller, as indicated at 54.
If on one of his allotted three tries, the caller has entered a
valid account number, the computer goes into an output mode, as
indicated by output block 46, wherein the voice answer-back unit 22
is controlled to compose a voice transmission requesting the entry
of a second multi-digit number, such as a meter number, uniquely
identifying the postage meter to be recharged. as indicated by
input block 55, the computer converts to the input mode awaiting
receipt of the numeric entry of the meter number of the caller's
postage meter 24. Upon entry of the meter number, the computer
determines, as represented by decision block 56, whether or not the
caller's account file held in memory and file identified by the
previously entered account number includes a meter number identical
to the one entered by the caller; it being appreciated that the
caller may have more than one postage meter. If identity is found,
the program exits decision block 56 on branch 57 leading to output
block 60. On the other hand, if identity is not found, the program
exits decision block 56 on branch 58 leading to a second decision
block 59, wherein a check is performed to determine how many
attempts the user has been afforded to enter a valid meter number
after having entered a valid account number. If the user has had
less than three such attempts, the program exits decision block 50
on branch 61, wherein the computer enters an output mode, indicated
by output block 62, to control the voice answer-back unit to
compose a voice transmission to the effect that the meter number
entry is not valid and to enter it again. The program reverts back,
over branch 63 to the input of block 55 as the computer awaits
another attempt by the user to enter a valid meter number. If the
caller has not done so on three passes through decision block 56,
the program exits decision block 59 on branch 64 to output block
65, wherein the computer again advises the caller that his meter
number entry is not valid and formulates the voice instruction to
call a particular telephone number for personal assistance. The
computer thereupon breaks the telephone connection with the caller,
as represented at 54. The philosophy in this situation is that
since the caller had previously entered a valid account number it
is probably not a spurious call. Thus, the caller is requested to
call for personal assistance in determining why the caller was
unable to enter a valid meter number after three attempts, having
previously entered a valid account number.
Assuming the caller has entered a valid account number as well as a
valid meter number, the computer, as indicated in output block 60
controls the voice answer-back unit to formulate a voice
transmission requesting the caller to enter the reading in the
ascending register (A/R) of the identified postage meter to be
recharged. The computer then converts to the input mode, as
indicated in input block 66, awaiting entry of the ascending
register reading. Upon receipt, the computer reverts to the output
mode to control the voice answer-back unit to formulate the voice
transmission requesting the user to enter the reading in his
descending register (D/R), as indicated by output block 67. The
computer, as indicated in input block 68, awaits the entry of the
user's descending register reading, and, upon receipt, the program
proceeds over branch 69 to decision block 70. Here, the computer
checks the descending register reading just entered with the
reading of the descending register (D/R') stored in the computer
memory under the entered meter number on the occasion of the
previous recharging of the user's meter. Since the descending
register is decremented by the amount of postage issued with each
meter cycle, the current descending register reading cannot be
greater than the descending register reading stored in the computer
memory. If, however, this is found to be the case, the program
exits decision block 70 on branch 71 to a second decision block 72
wherein the computer tests to determine how many times the current
descending register reading has been found to exceed the previous
descending register reading. If the number of passes through
decision block 72 is less than three, the program exits on branch
73 to an output block 74. The computer then controls the voice
answer-back unit to compose a voice response advising the caller,
in effect, that his descending register entry is not valid and to
repeat the entries of the ascending and descending register
readings of his meter. The program exits output block 74 on branch
75 and reenters output block 60 and preceeds through input/output
blocks 66, 67 and 68 to decision block 70. If after the third pass
through this portion of the program the current descending register
reading is still found to be larger than the stored descending
register reading, the program exits decision block 72 on branch 76
to output block 65, wherein the voice answer-back unit is
controlled by the computer to formulate a voice transmission
inviting the caller to call for human assistance.
Still referring to FIG. 2, if the descending register reading
entered by the caller is not larger than the previous descending
register reading held in memory, the program exits decision block
70 and enters a decision block 78. The computer sums the ascending
and descending register readings (SOR) entered by the caller and
compares this total with the sum of the same two register readings
(SOR') stored in the memory as the result of the last recharging of
the identified meter. If everything is in order, these two totals
should be equal. This is seen from the fact that as the postage
meter is used subsequent to the last recharging, the amounts of
postage by which the descending register is decremented are equal
to the postage amounts by which the ascending register is
incremented. Consequently, the total of these two register readings
should remain constant between rechargings. If the two sums are
equal, the program exits decision block 78 on branch 79 where some
additional checks are performed pursuant to issuing the next
combination for the combination lock 26 associated with the meter
to be recharged.
On the other hand, if the sums of the entered register readings and
the register readings held in memory are not equal, the computer
performs one or more additional checks in an effort to determine if
the inequality detected in decision block 78 arose for reasons
other than an erroneous digit entry by the caller.
Thus, as seen in FIG. 2, in the event of inequality the computer
exits decision block 78 and enters decision block 80, wherein the
computer checks to see if the ascending register of the identified
postage meter overflowed since the last recharging. To perform this
check, the computer compares the sum of the register readings
entered by the caller with the sum of the register readings held in
memory minus the size of the ascending register. That is, if the
ascending register has a six digit capacity, for example, capable
of registering readings from zero to 999,999, its register size is
1,000,000. It will be seen that if the ascending register is
incremented through zero since the last recharging of the meter,
this event can be acccommodated in a sum of registers check by
substracting from the sum of the stored register readings the
register size, i.e., 1,000,000. This computation compensates for
the fact that the ascending register has overflowed and decision
block 80 will detect an equality. In such event, the program exits
on branch 79 pursuant to issuing the next combination to the
caller.
If ascending register overflow was not the reason for the detected
inequality in the sum of registers check, the program enters still
another decision block 82, wherein the computer checks to see if
the caller failed to actually recharge his meter the last time he
called to receive a new combination. That is, the caller having
previously called to receive a new combinaton did not enter it into
his combination lock 26 and increment his descending register with
the amount of allotted additional postage. As will be seen, the
computer, at the time of issuing each new combination, increments
the descending register reading held in memory with the amount of
additional postage to which the caller is given access, and, if he
does not recharge his meter, the sum of registers checks performed
in decision blocks 78 and 80 will have failed. To determine if this
situation exists, the computer compares the sum of the register
readings entered by the caller with the sum of the register
readings held in memory minus the increment of postage previously
allotted to the caller. If an equality is now detected in decision
block 82, the program exits on branch 83, and the computer proceeds
to issue the same combination stored in the memory that was given
on the previous call but which had not been entered into the
combination lock for some reason. The caller may then recharge his
postage meter with the increment of postage he previously had been
given access to, and for which he previously had been charged.
However, the computer does not update the caller's file. Therefore
he is not charged for the same increment of postage again.
If the check illustrated by decision block 82 fails, the computer
makes one final check, illustrated by decision block 84, to
determine that the failure of the sum of registers checks
illustrated in decision block 78, 80 and 82 was for a reason other
than an erroneous digit entry by the caller. This final check
involves testing to see if the reason for the sum of registers
inequality arose, because the caller's ascending register
overflowed and he also neglected to recharge his meter the last
time he called and was given the combination permitting him to
recharge his meter. This check is carried out by comparing the sum
of the registers entered by the caller to the sum of the registers
held in computer memory minus the allotted increment of postage
minus the ascending register size. If an equality is now detected,
the program exits decision block 84 on branch 83 pursuant to
issuing the same combination to the caller that he was given the
last time he called. On the other hand, if an equality is still not
obtained, the program exits decision block 84 on branch 85 to
decision block 72, which checks to see how many passes through
decision blocks 70, 78, 80, 82 and 84 the computer has executed for
this particular caller. If the number of passes is less than three,
the program exits decision block 72 on branch 73 to output block
74, and the caller is requested to reenter his ascending and
descending register readings. If, on the third pass through these
decision blocks, a sum of registers inequality is still detected,
the program exits decision block 72 on branch 76 to output block
65, and the caller is invited to call for human assistance.
When the program exits decision blocks 78 or 80 on branch 79, the
computer checks the caller's account, as represented by decision
block 90, to determine that his account has a sufficient credit
balance to pay for the increment of postage with which he is
seeking to recharge his meter. If the credit balance is found to be
insufficient, the program exits decision block 90 to connector B,
which is common to connector B at branch 76 leading to output block
65, wherein the computer formulates, via the voice answer-back
unit, the voice transmission inviting the caller to call for human
assistance.
When the computer determines that the caller's account has an
adequate credit balance, the program exits decision block 90 and
enters decision block 92, wherein the computer checks to determine
whether or not the caller has used up the entire random sequence of
combinations accomodated in the meter's combination lock. If the
combination lock is of the type disclosed in U.S. Pat. No.
3,664,231, noted above, wherein the random sequence of combinations
is established by a series of perforations in a paper tape, the
check illustrated by decision block 92 determines when the paper
tape is used up and the installation of a replacement tape is
required. Assuming, for example, that there is a random sequence of
500 lock combinations punched into the tape, the computer keeps
track of the number of combinations issued and, when 500 have been
issued, the program exits decision block 92 to connection B, common
to the input of output block 65. The caller is thus invited to call
for human assistance.
Assuming that the entire sequence of combinations has not been
issued, the program exits decision block 92 to decision block 94,
wherein the computer checks to see that, with the descending
register reading entered by the caller, the additional increment of
postage which the caller is being given access to will not overflow
the descending register. Should the descending register overflow
when being recharged, the credit balance lockout feature built into
conventional postage meters will prevent the caller from using all
of the postage increment if it were recharged into the meter. If
the computer determines that descending register overflow will
occur, the program exits decision block 94 to connection B and
thence to output block 65, requesting the caller to call for human
assistance.
Having cleared all of the above described checks, the computer is
now programmed to provide the new combination for the postage meter
identified by the meter number entered by the caller. There are of
course a number of ways in which this can be done. For example, the
computer may store for each remote meter serviced by the data
center the same random sequence of combinations as are accommodated
in the combination lock adapted thereto. The computer would then
atuomatically retrieve the next combination in sequence from its
memory for issuance to the caller. This approach has the distinct
drawback of taking up inordinate amounts of computer memory. A more
practical approach is to utilize a random number generator
sub-routine, as generally indicated by sub-routine block 96 in FIG.
2 and as disclosed in greater detail in the flow diagram of FIG.
3.
As seen in FIG. 3, pursuant to generating the new combination, the
computer, as indicated by block 98, retrieves a random seed number
stored in its memory under the meter number of the particular
postage meter to be recharged. This random number is checked, as
illustrated by decision block 100, to determine if it is odd or
even, and if even, it is incremented by one, as indicated by block
102. This is done because the particular random number generation
method illustrated, a modified power residue method, has a longer
repeat period when using odd numbers rather than even numbers. Thus
odd seed number, as indicated by block 104, is multiplied by a
constant to develop a new random number. Assuming a 32-bit computer
word length, the overflow created by this multiplication is
discarded and the 32 least significant bits become the new random
seed number. The 12 most significant bits of this random number are
stored in binary coded decimal form as the four digits of the first
half of the new combination. That is, as indicated in FIG. 4, the
12 most significant bits, indicated at 108, of the random number
are divided into four groups 108a - 108d of 3 bits, each
representing a decimal digit zero through seven of the first half
of the new combination. This first half of the new combination for
entry in key cluster 30 is stored, while the computer checks, as
indicated by decision block 110 to determine whether this is the
first or second pass through the random number generator
sub-routine for the identified postage meter. If it is the first
pass, the new random number generated by the computation of block
104 is used, as indicated at block 112, to re-enter the sub-routine
of FIG. 3 at decision block 110. If this new random number is even,
it is incremented by one. If it is already odd, this new random
number is multiplied by the constant, as indicated by block 104, to
generate still another random number. The overflow bits are
discarded, and the 12 most significant bits of the resulting 32
-bit random number are retained as the four digits in BCD form of
the second half of the new combination for entry in key cluster 32.
The new random number generated on the second pass through this
sub-routine is stored as the new seed number as indicated by block
114, for the random number generator sub-routine when the
identified postage meter is to be again recharged. As indicated by
block 116 in FIG. 3, the two halves of the new combination are
assembled and used as the basis for controlling the voice
answer-back unit to compose the new combination for voice
transmission back to the caller, as indicated by output block 118
in FIG. 2.
It is understood that the random number generation method used in
calculating each combination of the random sequence (sub-routine
96) is also used in preparing the punched paper tape or other form
of storage media accommodated in the lock to successively qualify
the identical random sequence of combination for opening or
actuating the lock. Thus the sub-routine 96 and the particular
combination lock for the identified meter to be recharged each
progress through the same unique random sequence of combinations in
tandem, since the identical seed numbers are used in each case. It
will be appreciated that the combination locks may be equipped with
micro-computers using the same random number generation method to
calculate the new combinations in concert with sub-routine 96.
It will be appreciated that the pseudo-random number generation
sub-routine 96 illustrated in FIG. 3 is intended as purely
illustrative, as there are manifold known random number generation
algorithms which may readily be used in the practice of our
invention.
Returning to FIG. 2, prior to the voice tranmission of the new
combination to the caller, the computer executes a sub-routine,
indicated at 119, wherein the caller's account and postage meter
file, held in memory, are updated. While the computer memory may be
organized in a number of ways, preferably each postage meter is
allotted a block of memory locations addressed by a unique meter
number which is entered by the caller in accordance with input
block 55. Each account is also allotted a block of memory locations
addressed by a unique account number, as entered in accordance with
input block 42. In each meter number addressed memory block is
stored the account to which that identified postage meter belongs.
As represented by decision block 56, the computer, in effect,
determines that the entered meter number is not only stored in the
memory, but also cross-checks to determine that the identified
meter belongs to the previously entered account number before
preceeding to that part of the program calling for entry of the
ascending register reading represented by output block 60 in FIG.
2. Stored in each account number addressed block is the credit
balance for that particular account. This credit balance is debited
in sub-routine 119 with the increment of postage to which the
caller is given access when the function represented by output
block 118 is executed. This credit balance is credited by the entry
into the computer of payments remitted by the caller. Deficiency of
this stored credit balance figure is checked by decision block 90
prior to the calculation of the new combination in sub-routine
96.
In each meter number memory block is also stored the fixed
increment of postage by which that particular meter can be
recharged; it being understood that the amount of this postage
increment may vary from meter to meter. Also stored in each meter
number memory block is the ascending register and descending
register sizes for that particular postage meter. This information
is used in decision blocks 80, 84 and 94. Except for the credit
balance figure for each account, the above data remains constant,
as stored in memory. The remaining data stored in memory under each
meter number is variable data which is updated pursuant to
sub-routine 119. This data includes the updated ascending and
descending register readings, as entered by the caller, the new
random seen number derived by the random number generator
sub-routine of FIG. 3 and stored until such time as the next new
combination is to be calculated, the combination calculated by the
random number generator sub-routine for issuance to the caller, and
the count of the combinations issued as used in decision block
92.
It is seen from FIG. 2, when either decision blocks 82 or 84
determine that the caller failed to recharge the postage meter in
question with the postage increment to which he was previously
given access, sub-routine 96 is bypassed, and the computer
retrieves the combination in memory calculated by sub-routine 119
on the previous occasion. This stored combination is then
transmitted back to the caller without altering the caller's credit
balance and the other variable data for that particular postage
meter stored in memory.
Returning to FIG. 2, once the new combination is transmitted to the
caller, the computer is conditioned to accept an entry of three
digits, as represented by input block 120. The computer goes
through a time out function awaiting the entry of three digits. If,
at the end of the time out function, no three digits have been
received, the program hangs up, as indicated at 128, to break the
telephone connection with the caller, if the caller has not already
done so. It will be appreciated that the program will execute a
similar time out function in anticipation of the receipt of all
data entries, (e.g., input blocks 42, 55, etc.) and will hang up if
such entries are not timely. If the caller keys in the letters RPT
(778), the abbreviation for "repeat," the program exits decision
block 122 on branch 123, returning to the entry for output block
118, and the computer controls the voice answer-back to transmit
the same new combination back to the caller. If, on the other hand,
the caller enters the letters AGN (246), the abbreviation for
"again," the computer determines that the caller desires still
another increment of postage and the program exits decision block
124 onto connection A which is common to the input block 60. The
computer then requests entry of the ascending register reading and
the new descending register reading, i.e., with the new increment
of postage to which the caller has just been given access added in.
The new, incremented descending register reading must be
transmitted to the data center, whether or not it has in fact been
incremented, otherwise the caller will be given the same
combination when the program reaches decision block 82. Thus, the
end result would be the same as though the caller had entered the
letters RPT rather than AGN. However, if the incremented descending
register reading is entered, the caller will be given the next
combination in sequence, assuming his credit balance is still
sufficient (decision block 90), the sequence of combinations in his
combination lock has not been expended (decision block 92), and the
descending register will not overflow (decision block 94).
It will thus be seen that the objects of the invention made
apparent from the foregoing description are efficiently attained,
and, since certain changes may be made in carrying out the above
method without departing from the scope of the invention, it is
intended that all matter contained in the above description or
shown in the accompanying drawings shall be interpreted as
illustrative and not in a limiting sense.
* * * * *