Passcodes

FIELD

0001The specification generally relates to security and preventing access to an entity by unauthorized entities.

BACKGROUND

0002The subject matter discussed in the background section should not be assumed to be prior art merely as a result of its mention in the background section. Similarly, a problem mentioned in the background section or associated with the subject matter of the background section should not be assumed to have been previously recognized in the prior art. The subjection matter in the background section merely represents different approaches, which in and of themselves may also be inventions, and various problems, which may have been first recognized by the inventor.

0003In many applications a password is required to grant access to a system or authorize a transaction. Today many users have so many different passwords that it is difficult to remember them. In other cases, a password can be stolen by a thief, making passwords susceptible to fraud.

0004<patcit id="pcit0001" dnum="US6636973B1"><text>US 6,636,973 B1 </text></patcit>discloses a method for dynamically changing a user's password for entry onto a computer network. The method uses a random or pseudo-random process to change the user's password during or after a log on attempt by the user. When registering for the server computer, the user submits a biometric template, which is then checked each time the user attempts to log on to the network. The user logs into the network by using a biometric sensing device to capture the user's biometric template, which then sends the template to a server to check for a match. A match causes the currently stored password for the user to be transmitted to the network to grant network access for the user. A new password is then created using a random or pseudo random process to ensure that an entity who acquires the old password cannot gain access to the network.

0005<patcit id="pcit0002" dnum="US2002095586A1"><text>US 2002/095586 A1 </text></patcit>discloses continually sensing for the presence of the user at the user device, such via repeated retina scans or fingerprint scans, and if the scanning of the retina or fingerprint stops, the transaction is stopped. <patcit id="pcit0003" dnum="US2002095586A1"><text>US 2002/095586 A1 </text></patcit>discloses the use of public and private cryptographic keys and digital signatures to identify the user. However, the biometric scan itself is sent for authentication to the authenticating authority.

0006<patcit id="pcit0004" dnum="US6307956B1"><text>US 6,307,956 B1 </text></patcit>discloses a stylus, which has a fingerprint sensor built into the stylus, so that the user may use the stylus at a point to sale and thereby verify the user's identity to the merchant or credit card company, for example, stored fingerprint is encrypted. The fingerprint as opposed to a password is sent to the authenticating authority.

SUMMARY

0007The invention is defined by the independent claims. The dependent claims concern optional features of some embodiments of the invention.

BRIEF DESCRIPTION

0008In the following drawings like reference numbers are used to refer to like elements. <ul id="ul0001" list-style="none" compact="compact"><li><figref idref="f0001">FIG. 1A</figref> shows a block diagram of an example of a system for maintaining the security of a secure entity.</li><li><figref idref="f0002">FIG. 1B</figref> shows a block diagram of an example of the system of <figref idref="f0001">FIG. 1A</figref>.</li><li><figref idref="f0003">FIG. 1C</figref> shows a block diagram of an example of the system of <figref idref="f0001">FIG. 1A</figref>.</li><li><figref idref="f0004">FIG. 2A</figref> shows a block diagram of an example of the system of <figref idref="f0001">FIG. 1A</figref>.</li><li><figref idref="f0005">FIG. 2B</figref> shows a block diagram of an example of computer system, which may be used as any of the system of <figref idref="f0004">FIG. 2A</figref> and/or for any of the blocks in <figref idref="f0001 f0002 f0003">FIGs. 1A-C</figref>.</li><li><figref idref="f0006">FIG. 3A</figref> shows an example of a passcode device.</li><li><figref idref="f0006">FIG. 3B</figref> shows an example of a passcode device.</li><li><figref idref="f0007">FIG. 4</figref> shows an example of a passcode device.</li><li><figref idref="f0007">FIG. 5A</figref> shows an example of the system of <figref idref="f0001">FIG. 1A</figref>.</li><li><figref idref="f0008">FIG. 5B</figref> shows an example of the system of <figref idref="f0001">FIG. 1A</figref>.</li><li><figref idref="f0009">FIG. 6</figref> shows a block diagram of a circuit of an example of a passcode device.</li><li><figref idref="f0010">FIG. 7</figref> shows a flowchart of an example of a method for setting up a passcode device for use by a particular user.</li><li><figref idref="f0011">FIG. 8</figref> shows a flowchart of an example of a method of requesting access to a secure entity.</li><li><figref idref="f0012">FIG. 9</figref> shows a flowchart of an example of a method of handling a request for access to a secure entity.</li><li><figref idref="f0013">FIG. 10</figref> shows a flowchart of an example of a method for carrying out one of the steps of <figref idref="f0012">FIG. 9</figref>.</li><li>. <figref idref="f0014">FIG. 11</figref> shows a flowchart of an example of a method for setting up part of a system so that a user may access a secure entity.</li><li><figref idref="f0015">FIGs. 12A</figref> and <figref idref="f0016">12B</figref> show a flowchart of an example of a method for handling a request for access to a secure entity.</li><li><figref idref="f0017">FIG. 13</figref> shows a flowchart of an example of a method of installing a part of the system of <figref idref="f0001">FIG. 1A</figref>.</li><li><figref idref="f0018">FIG. 14</figref> shows a flowchart of an example of a method for assembling the passcode device.</li></ul>

DETAILED DESCRIPTION

0009In general, at the beginning of the discussion of each of <figref idref="f0001 f0002 f0003 f0004 f0005 f0006 f0007 f0008 f0009">FIGs. 1A-6</figref> is a brief description of each element, which may have no more than the name of each of the elements in the one of <figref idref="f0001 f0002 f0003 f0004 f0005 f0006 f0007 f0008 f0009">FIGs. 1A-6</figref> that is being discussed. After the brief description of each element, each element is further discussed. In some of <figref idref="f0001 f0002 f0003 f0004 f0005 f0006 f0007 f0008 f0009">FIGs. 1A-6</figref> the further discussion of each element is usually in the numerical order of the elements. In some of <figref idref="f0001 f0002 f0003 f0004 f0005 f0006 f0007 f0008 f0009">FIGs. 1A-6</figref> the further discussion of each element discusses a group of the elements together. In some of <figref idref="f0001 f0002 f0003 f0004 f0005 f0006 f0007 f0008 f0009">FIGs. 1A-6</figref> after the further discussion of each element, there is a discussion of how all the elements cooperate with one another. In general, each of <figref idref="f0001 f0002 f0003 f0004 f0005 f0006 f0007 f0008 f0009 f0010 f0011 f0012 f0013 f0014 f0015 f0016 f0017 f0018">FIGs. 1A-14</figref> is discussed in numerical order and the elements within <figref idref="f0001 f0002 f0003 f0004 f0005 f0006 f0007 f0008 f0009 f0010 f0011 f0012 f0013 f0014 f0015 f0016 f0017 f0018">FIGs. 1A-14</figref> are also usually discussed in numerical order to facilitate easily locating the discussion of a particular element. Nonetheless, there is no one location where all of the information of any element of <figref idref="f0001 f0002 f0003 f0004 f0005 f0006 f0007 f0008 f0009 f0010 f0011 f0012 f0013 f0014 f0015 f0016 f0017 f0018">FIGs. 1A-14</figref> is necessarily located. Unique information about any particular element or any other aspect of any of <figref idref="f0001 f0002 f0003 f0004 f0005 f0006 f0007 f0008 f0009 f0010 f0011 f0012 f0013 f0014 f0015 f0016 f0017 f0018">FIGs. 1A-14</figref> may be found in, or implied by, any part of the specification.

0010<figref idref="f0001">FIG. 1A</figref> is a block diagram of an example of a system 100. System 100 includes a passcode device 101, an administrator 102, and a secure entity 103.

0011System 100 is an example of a system in which the security of a secure entity is kept by requiring a user to submit a passcode (e.g., a password) in order to gain access to the secure entity. The term "user" refers to someone that has access to passcode device 101. The user may use passcode device 101 to gain access to a secure entity. Any sequence of bits (which may represent any string of symbols) may be used as a passcode. In some cases, the passcode may be directly transmitted without human intervention to the administrator, so the sequence of bits may not have a visual display in standard formats such as ASCII, Unicode, and so on. For example, the first sequence of 8 bits in the passcode could in ASCII represent the end of file character, which currently does not have a visual representation. In other embodiments where the passcode is displayed as a sequence of symbols on a graphical display, then the symbols may be chosen from any subset of or combination of alphanumeric, punctuation, picture symbols, math, upper case, and/or lower case symbols, for example. The choice of alphanumeric symbols may include characters from a multiplicity of languages. An example of an alphanumeric passcode with 8 symbols 4R1pa5Wx. An example of a possible passcode with 8 symbols is <img file="EP1844567B1_D0001.tif" />. An example with 16 symbols including punctuation and other symbols is &amp;x#W<img file="EP1844567B1_D0002.tif" />q61!j<img file="EP1844567B1_D0003.tif" />uS_m.

0012Passcode device 101 may be used for generating passcodes and/or for setting up a new user in system 100. Setting up a new user may include "registering" the new users. Registering a new user refers to the process of adding a new user so that the new user is able to use a system, such as passcode device 101 or system 100. Passcode device 101 may have multiple other uses.

0013In an embodiment, passcode device 101 generates a new passcode each time a user wants to gain access to the secure entity. In an embodiment, after the passcode is used, the passcode is discarded and is not stored. In an embodiment, after a passcode is used once, the passcode will no longer enable access to the secure entity. In an embodiment, passcode device 101 also acquires and/or stores information about a user that is used for identifying the user. When the user wants to access the secure entity, the user enters at least some identifying information (e.g., a valid fingerprint) into passcode device 101. If passcode device 101 is able to match the identifying information with identifying information stored in passcode device 101, then passcode device 101 generates a passcode, which is used for gaining entry to a secure entity (e.g., a newly acquired fingerprint may be matched with information derived from earlier acquired fingerprints). The identifying information may be stored in passcode device 101 in association with a user ID. Thus, in this embodiment, each time a user submits identifying information to the passcode device 101, a new one-time passcode is created. An embodiment of the passcode device 101 uses a secure device (as passcode device 101) that produces unique passcodes from the identifying information, and the unique passcodes are used as one-time passcodes. In an embodiment, for each acquired set of identifying information, the derived passcodes created are unique. In an embodiment in which the passcode may only be used once, the user does not have to remember her passcode. For example, passcode device 101 may generate a new passcode every time a user submits a valid fingerprint. In an embodiment in which a new passcode is generated for each request for access, stealing the passcode is of, at best, limited use, because after the passcode has been used, the passcode is no longer valid.

0014In other embodiments, passcode device 101 generates a new passcode less frequently than every time a user submits valid identifying information. For example, a new passcode may be generated every other time or on a random schedule, which the user may be unaware of. In an alternative embodiment, the passcode may be used multiple times prior to being discarded. In an alternative embodiment, the passcode is stored for a brief period of time, which may extend beyond the passcodes initial use. The discarding of the passcode may depend upon the number of uses and/or a length of period of time after the passcode was generated.

0015In an alternative embodiment, the frequency of repeated passcodes issued to different users is low enough such that it is unlikely that one of two users that have been issued the same passcode will try to access secure entities that only the other of the two is entitled to access. In an embodiment, the frequency of passcodes issued to the same user being repeated is low enough that it is unlikely that the interception of an old passcode will be useful to a hacker. Since the passcode is not stored beyond an expiration time, the passcode itself cannot be stolen accept during the brief period between the time the passcode is generated and the passcode expires. In an embodiment in which the passcode is valid for only one use, the passcode does not need to be stored at all and can only be stolen during the brief period between when the passcode is generated and used. In an embodiment, each time the user enters user information (e.g., a fingerprint) the current passcode is displayed or transmitted (whether or not the current passcode is a one-time passcode), and consequently, the user does not need to remember the passcode.

0016In an embodiment, a timestamp may be associated with a one-time passcode or other passcode. If the current time is later than the associated timestamp, when the passcode is submitted to an "administrator," then the passcode has expired, is invalid, and access would be denied. The word administrator is used to refer to an entity that grants or denies access to the secure entity.

0017There are many types of identifying information that may be stored by passcode device 101, such as fingerprints, a birthday, a favorite number, a social security number, and/or a driver's license, a profile, an image of a face, an iris scan, a toe print, a handprint, and/or a footprint. In an embodiment, the item used to generate the passcodes is any item that is unique. In this specification, using a first item (e.g., a fingerprint) to "generate" a second item (e.g., a passcode) may refer to using the first item to "directly" generate the second item or to "indirectly" generate the second item by, for example, first generating one or more intermediary items from which the second item is ultimately generated. The intermediary items may include a chain of multiple intermediary items that each generated one from another. In an embodiment the item used to generate the passcode is one that is difficult to fabricate, guess, find by trial and error, and/or compute. In an embodiment, the item used to generate the passcodes is uniquely associated with the user. In an embodiment, the item used to generate the passcodes has an unpredictable element to it (e.g., the unpredictable manner in which the patterns of lines in fingerprints differ between fingerprints).

0018During a registration process identifying information about a new user may be stored in passcode device 101. In an embodiment passcode device 101 includes a secure area for acquiring identifying information, storing the identifying information, and/or information related to, or derived from, the identifying information. The secure area is discussed further in conjunction with <figref idref="f0009">FIG. 6</figref>. The registration process is discussed further in conjunction with <figref idref="f0002">FIGs. 1B</figref>, <figref idref="f0003">1C</figref>, <figref idref="f0011">8</figref>, and <figref idref="f0014">11</figref>.

0019In addition, optionally, the passcode device 101 can be a standalone and/or portable device. It is more difficult for an attacker to gain access to passcode device 101 if passcode device 101 is a standalone device, because there are less opportunities for another device to inspect or otherwise access the contents of passcode device 101 compared to if passcode device 101 is not a standalone device. Additionally, in an embodiment in which passcode device 101 is a standalone device, it is more difficult for an unauthorized entity to steal the identifying information associated with the user than were passcode device 101 not a standalone device.

0020. The portable embodiment enables users to generate one time passcodes in remote places, such as inside an airplane, on an oil tanker, on a ship, in a warehouse with shipping containers using wireless communication, in a satellite, at places at which an AC power source is difficult to access or inaccessible, and/or at other places. More details about various possible embodiments of passcode device 101 are discussed in conjunction with subsequent <figref idref="f0002 f0003 f0004 f0005 f0006 f0007 f0008 f0009 f0010 f0011 f0012 f0013 f0014 f0015 f0016 f0017 f0018">FIGs. 1B-14</figref>.

0021Administrator 102 receives the requests for access to a secure entity from passcode device 101, and decides how to handle the request. For example, administrator 102 may receive a passcode from passcode device 101 and may cause the passcode to be authenticated. In an embodiment, administrator 102 may check, or cause other entities to check, whether a passcode is derived from one of the registration codes and/or passcode generators stored in the database.

0022Similar to the passcode, any sequence of bits may be used as a registration code. In some cases, the registration code may be directly transmitted without human intervention to the administrator, so the sequence of bits may not have a visual display in standard formats such as ASCII, Unicode, and so on. For example, the first sequence of 8 bits in the registration code could in ASCII represent the end of file character, which currently does not have a visual representation. In other embodiments where the registration code is displayed as a sequence of symbols on a graphical display, then the symbols may be chosen from any subset of or combination of alphanumeric, punctuation, picture symbols, math, upper case, and/or lower case symbols, for example. The symbols that the user may choose from may be any subset of or combination of alphanumeric, punctuation, math, upper case, and/or lower case symbols, for example. The choice of alphanumeric symbols may include characters from a multiplicity of languages. An example of a registration code with 16 symbols is 1Ae58GnZbk3T4pcQ and a registration code with punctuation and other symbols may also be used. An example with 32 symbols is 1!56hs#K♀3_4xP^∗7:y2iW=K;r.+4vN? There may be at least one unique registration code for each user and/or passcode device 101. The same criterion and/or restrictions for both passcodes and registrations codes for determining what sequences of characters are valid.

0023Administrator 102 may be a human being, software, a computer, an electro-mechanical lock, or other machine that grants a particular user access to its resources and/or enables a particular event (e.g., a financial transaction, or landing a plane at an airport, and so on). Administrator 102 has the capability (e.g., authority) to grant or deny the user, associated with passcode device 101, access to the secure entity. If the passcode is found to be authentic, then administrator 102 grants the user, associated with passcode device 101, access to the secure entity. In an embodiment, the passcode is accepted by administrator 102 only once. In an embodiment, after accepting the passcode, administrator 102 expects a different passcode for the next request.

0024Several different embodiments are discussed above in conjunction with passcode device 101 that relate to different criterion and/or durations of time for when a passcode is valid. Administrator 102 has a corresponding way of behaving in terms of whether a given passcode is accepted depending on the embodiment. For example, in an embodiment in which the passcode is valid for only a specified number of uses (which may be a relatively small number of uses) instead of being valid for only one use, administrator 102 accepts the passcode as valid for only the specified number of times. In an alternative embodiment, the passcodes validity may be dependent on time period (which may be relatively short) instead of, or in addition to, being valid for only one or a specified number of uses. As another example, in an embodiment in which the passcode is associated with a timestamp, administrator 102 may deny access for a passcode submitted with an expired timestamp.

0025In an embodiment, to authenticate a passcode instead of comparing the passcode to a previously received passcode, administrator 102 generates the passcode independently from passcode device 101. Consequently, in this embodiment, instead of storing the actual passcode, administrator 102 stores a method of generating the passcode that is expected to result in the same passcode generated by passcode device 101. In an embodiment, administrator 102 stores and/or uses the same method of generating passcodes that passcode device 101 uses.

0026In an embodiment in which passcode device 101 and administrator 102 use the same method for generating a passcode, the registration process may involve associating a particular method of generating passcodes with a user and/or passcode device 101. The registration process may involve synchronizing the methods used by passcode device 101 and by administrator 102 so that at a particular attempt to gain access, administrator 102 and passcode device 101 generate the same passcode. The registration process may involve associating a particular registration code (which may also be referred to as a seed) with a particular user and/or passcode device 101. Administrator 102 may be part of the secure entity, a separate entity, and/or may be located in location that is remote from the secure entity.

0027Secure entity 103 is the secure entity that the user (which is associated with passcode device 101) desires to access. Secure entity 103 is the entity to which administrator 102 has the capability to determine whether the user is entitled to access. Some examples of secure entities are locks, doors, cars, houses, websites, bank accounts, ATMs, medical records, authorization to perform a financial transaction, or some other type of event that requires security.

0028The lines connecting passcode device 101, administrator 102, and secure entity 103 represent paths of communication. These lines may represent physical communication lines, wireless communications, sonar communications, verbal communications, and/or other communications. The dashed part of the line connecting passcode device 101 with secure entity 103 indicates the capability of administrator 102 to prevent or allow access to secure entity 103.

0029Although in <figref idref="f0001">FIG. 1A</figref> only one passcode device 101, administrator 102, and secure entity 103 are illustrated, there may be a multitude of passcode devices 101 that can access secure entity 103 and each passcode device 101 may be able to access multiple secure entities 103. Similarly, there may be several administrators 102 that are capable of granting access to a particular secure entity 103, and each administrator may be capable of granting access to several secure entities 103. Further, a particular passcode device 101 may have a choice of several administrators 102 via which to gain access to a particular secure entity 103.

0030<figref idref="f0002">FIG. 1B</figref> shows one of many possible embodiments of system 100. In the embodiment of <figref idref="f0002">FIG. 1B</figref>, passcode device 101 includes setup portion 104 and request portion 106. In the embodiment of <figref idref="f0002">FIG. 1B</figref>, system 100 includes setup 108, request for access 110, reply 112, access to secure device 114, and administrator 102. Administrator 102 may include setup portion 116 and request portion 118. Request portion 118 may include error handler 120.

0031In <figref idref="f0002">FIG. 1B</figref>, each passcode, denoted as P_i, is a sequence of bits. Although this specification uses a specific notation, the invention is in no way limited by this notation. Software implementing the methods of this specification may use a notation that is unrelated to the notation used in this specification. Setup portion 104 may be used for registering a new user, configuring passcode device 101, and/or for setting up passcode device 101. Setup portion 104 acquires identification information, T. In an embodiment, setup portion 104 may generate a registration code, which may be denoted as R, for the sake of registering the user with another entity.

0032In an embodiment, a method, Φ₁, may be used for generating registration code R from the identification information. The method Φ₁ (which may be referred to as a generating method) may be a "one-way" method such as a one-way algorithm, a one-way function, and/or another one-way method. For example, the registration code may generated according to the equation Φ₁(T)=R. A one-way method, herein denoted Φ₁ (possibly having one or more indices representing different functions associated with different users or applications), has the property that given an output value z, it is computationally extremely difficult to find the input m_z such that Φ₁(m_z) = z. In other words, a one-way method is a method Φ₁ that can be easily computed, but whose inverse Φ₁^-1 is extremely difficult (e.g., impossible) to compute. One way to quantify the difficulty to compute Φ₁ given an output z, is to use the number of computations that are expected to be required to compute and/or guess Φ₁ For one type of method, it is that it is expected to take between O(2^n/2) and O(2ⁿ) computational steps to find or guess m_z, (depending on the how clever the one performing the computations is) where n is the number of bits in the output z. By using a one-way method for computing the registration code, even if the registration code is intercepted or otherwise stolen, it is unlikely that the registration code can be used to discover identifying information T.

0033One set of methods that may be used are one-way functions in which finding the inverse involves an operation that is mathematically indeterminate, impossible, intractable, or computationally impractical or difficult. For example, one method is to use a collection of step functions each of whose domain and range is [0, 1, 2, ... 255] and apply a distinct step function to a part of T. The information from T could be used to determine which step functions to select from the collection. If 16 step functions are chosen from the collection, then this would create an output of 128 bits. If n step functions are chosen from the collection, then this would create an output of 8n bits. An alternative to this would be to construct 32 matrices resulting from the step functions and compute the determinant modulo 256 for each of the 32 matrices. This creates a one-way function whose output is 256 bits. As another example, method Φ₁ could involve first represent user information T by a string of digits. Then, each digit of the string of digits could be multiplied by a corresponding digit from another string of digits, where at least one digit of the other string has a value of zero. The inverse of this method would involve at least one division by zero for each multiplication by a digit with the value of zero, which has no inverse, and consequently this method would be also be one-way. Similarly, functions for which finding their inverses involves computing a non-convergent series or non-convergent integral are other examples of classes of functions that may be used as one-way functions.

0034Another class of one-way functions involves computations that cause a loss of information or a discarding of selected pieces of information. Since some of the input information is lost in computing this class of one-way functions, the original input information (e.g., identifying information T) is difficult and may be impossible to recover. For example, a one-way function may be constructed by first performing a randomizing operation such as discarding random bits of information from the input, adding random bits of information to the input, and/or performing another randomizing operation to the input, and then another function may be applied to the information retained. Similarly, the same randomizing operations may be performed on the output of the function.

0035In an embodiment, a one-way hash function is used as method Φ₁. A hash function is one that accepts as its input argument an arbitrarily long string of bits (or bytes) and produces a fixed-size output. In other words, a hash function maps a variable length input m to a fixed-sized output, Φ₁(m). Typical output sizes range from 128 to 512 bits, but can also be larger. An ideal hash function is a function Φ₁ whose output is uniformly distributed in the following way. For example, suppose the output size of Φ₁ is n bits. If the input m is chosen randomly, then for each of the 2ⁿ possible outputs z, the probability that Φ₁(m) = z is 2^-n. This is a definition of an ideal hash function.

0036A real hash function with output size n bits should have the property that probability of each of its 2ⁿ possible outputs can be compared against the ideal probability of 2^-n. The chi-square function on n-1 degrees of freedom is a useful way to measure the quality of a real hash function. One uses a chi-square on n-1 degrees because there are n bits of output. And then one can compute a confidence level that the real hash function is close to an ideal hash function. Some typical confidence levels could be 90%, 95%, 99%, 99.5% and 99.999% depending on the level of security desired. In an embodiment, the hash functions that are used are one-way. Other types of one-way functions or methods may be used in place of a hash function. In an embodiment, the hash functions that are used are one-way. Other types of one-way functions or methods may be used in place of a hash function.

0037Any of a number of hash functions may be used for Φ₁. One possible hash function is SHA-256, designed by the National Security Agency and standardized by the NIST, [NIST_STANDARDS_1995]. The output size of SHA-256 is 256 bits. Other alternative hash functions are of the type that conforms to the standard SHA-1, which produces output values of 160 bits, and SHA-512, which produces output values of 512 bits, [NIST_STANDARDS_2001].

0038There are different methods Φ₁ that may be used for hashing fingerprints and other kinds of input. As an alternative to biometric data, other types of input could be used. For example, the input to a hashing function could be a sequence of symbols such as a passcode or a registration code (that is different from the passcode or registration code that is produced). Different types of methods of hashing are appropriate for different sizes of codes, and different types of fingerprint information that is passed to the hash function. One method is to take two different fingerprints and apply the hash function SHA-256 to each print. For ease of explanation, denote the hash function SHA-256 as Φ₁. Each application of Φ₁ to a fingerprint produces an output value of 256 bits. With two fingerprints, these bits are concatenated together to create a 512-bit code, which may be called C.

0039Another method for Φ₁ uses two different sections Sand T of a single acquired fingerprint, and produce a 512-bit code, C, by concatenating Φ₁(S) and Φ₁(T). An enhancement of this method can be used to create codes larger than 512-bits. Divide one acquired fingerprint into n sections: S₁, S₂, ..., S_n. Then concatenate the bits Φ₁(S₁), Φ₁(S₂), ..., Φ₁(S_n). This creates a code C that is 256n bits in length. For example, if the acquired fingerprint is divided into 10 sections, then this method would create a code with 2,560 bits. Any of the methods used as one-way functions for generating registration code R may also be used for generating passcodes or may be used at any of the other places in this application where a one-way function is useful. In another embodiment, method Φ₁ could be a random number generator.

0040Setup portion 104 uses registration code R and a method Φ₂, which may be a one-way function, to generate an initial passcode generator G₁. Initial passcode generator G₁ may be used for generating an initial passcode. A passcode generator, also known as a seed, can be a string of characters or other form of a code similar to registration code R or a passcode. Passcode generators may be stored securely by administrator 102 for use in verifying a passcode that is submitted by passcode device 101. The initial passcode generator G₁ may be generated according to the equation Φ₂(R)=G₁. Method Φ₂ (which also may be referred to as a generating method) may be the same as, or different from, method Φ₁.

0041Using passcode generators, such as G₁, enables the identification of a person without having access to the user's identifying data, such as the user's biometric data (e.g., fingerprints) or social security number or other identifying data. For example, some citizens and organizations are concerned about the government and other institutions storing a person's biometric data. Using a passcode generator, such as G₁, an institution can identify a person with a unique registration or passcode, which is derived from his or her fingerprint, other biometric data, and/or other authentication data.

0042Request portion 106 requests access to a secure device. In an embodiment, request portion 106 generates a passcode, which is used for requesting access to a secure entity. For example, request portion may use a method, Φ₃, and a generator, G_i, for generating a passcode P_i. Method Φ₃ may be a one-way method such as a one way function, similar to method Φ₂. Method Φ₃ (which may be referred to as a generating method) may be the same as or different from methods Φ₁ and/or Φ₂. For example, request portion 106 may compute a passcode using the equation, Φ₃(G_i)= P_i. The index i is used to indicate the ith passcode P_i, which in an embodiment is generated by the ith request for a passcode. In an embodiment, each passcode, P_i, is generated by using a different generator G_i. In an embodiment, each new generator, G_i+1, may be generated from a prior generator, G_i, using a method f, according to the equation, f(G_i)=G_i+1, for example.

0043In embodiments that use a graphical (e.g. LCD) display for the registration code and/or passcode, the function Φ₃ may be equal to D ∘ Φ where D is a display function and Φ is, for example, a one-way hash function. Here is an example of a display function D, titled code_to_alphanumeric_no_lOimplemented in the C programming language: <img file="EP1844567B1_D0004.tif" /><img file="EP1844567B1_D0005.tif" />

0044In general, the output of Φ₃(G_i) is a sequence of bytes and each of these bytes may be a value ranging from 0 to 255. In embodiments where there is a graphical display of the registration and/or passcode, the display function D is helpful because some byte values have a graphical output that is difficult to read by a user, (letter O versus the number 0), unreadable such as an end of file character, or a character that is difficult for a person to reliably describe, such as '&amp;', which some people do not know is called an ampersand. The primary purpose of the display function D is to convert unreadable or difficult-to-read byte values to readable byte values.

0045Setup 108, request for access 110, reply 112, and access to secure device 114 are different forms of communications in which passcode device 101 participates. Setup 108, request for access 110, and reply 112 are embodiments of the communications represented by the lines connecting passcode device 101, administrator 102, and secure entity 103 in <figref idref="f0002">FIG. 1B</figref>. In an embodiment, passcode device 101 may send registration code R to another entity, when sending setup 108. In an embodiment, passcode device 101 sends a user ID U with the registration code R to another entity or elsewhere as part of setup 108. Alternatively, passcode device 101 receives the user ID U from the other entity or from elsewhere. Request access 110 is a request for access to secure device 103. Request 110 may include sending passcode P_i, for example. In an embodiment, user ID U is also sent as part of request 110.

0046Reply 112 is a reply to request 110. Reply 112 may include a grant or a denial of request 110 for access to secure entity 103. In an embodiment, administrator 102 receives registration codes R from passcode device 101 as part of setup 108, and receives requests for access to a secure device from passcode device 101, as part of request 110. In an embodiment, administrator 102 may also grant or deny access to a user associated with passcode device 101, as part of reply 112. Access to secure device 114 are communications between passcode device 101 and secure entity 103. Access to secure entity 114 can be blocked from occurring or allowed to occur by administrator 102.

0047Administrator 102 includes setup portion 116, which uses registration code R received from passcode device 101, to generate the initial passcode generator G₁. In alternative embodiments, setup portion 116 may be located outside of administrator 102. Since administrator 102 may service several passcode devices 101 and/or several users, user ID U may be used to associate a registration code R, the generators G_i, and the passcodes generated with a passcode device 101 and/or a user U, which may be written as R_U and G_Ui, respectively. In this notation, the index U distinguishes the registration code R_U and generator G_U1 of user U from the registration code and generators of other users. Registration code R_U denotes registration code R after having been associated with user U at the administrator's side.

0048Since administrator 102 may need to authenticate the passcode submitted by passcode device 101, administrator 102 may need to generate the same set of passcodes as passcode device 101 in order to perform the authentication. Administrator 102 may generate the passcodes generated by passcode device 101 by using the same methods (e.g., one-way functions such as one-way hash functions or random number generators) and generators as used by passcode device 101. Consequently, administrator 102 uses method Φ_U2 to generate an initial passcode generator G_U1. Method Φ_U2 may be the same for all U as long as the registration codes R_U are different for each of the U's. In an embodiment, methods Φ_U2 are in general different for each U. If methods Φ_U2 are different, then the R_U's do not need to necessarily be different so long as the resulting passcodes for different users are in general different. The passcodes of different users can be different if methods Φ_U3 or passcode generators G_Ui are different for different users, while the G_Ui's will be different for different users if methods Φ_U2 and/or R_U are different.

0049Similar to passcode device 101, administrator 102 may generate the initial passcode generator G_U1 according to the equation Φ_U2(R_U)=G_U1. In an embodiment, for a given authorized user U, Φ_U2, R_U, and G_U1 are the same as Φ₂, R, and G₁.

0050Administrator 102 also includes request portion 118. In alternative embodiments, request portion may be located outside of administrator 102. For example, request portion 118 may be stored and executed on a system having a database that stores information being accessed. Request portion 118 receives, via request 110, passcode P_i and user ID U from request portion 106 of passcode device 101. Database 122 may be part of administrator 102, as illustrated in <figref idref="f0002">FIG. 1B</figref>, or may be located elsewhere. Database 122 may store current passcode generators and/or other user information. In an embodiment, based on user ID U, request portion 118 receives a passcode generator from database 122, and generates a passcode that is compared with the passcode P_i received from the passcode device. The passcode P_i generated is expected to be same passcode that user U sent with the current request if user U is an authorized user.

0051For example, request portion 118 may use method Φ_U3 and a passcode generator, G_Ui, for generating a passcode P_Ui. Method Φ_U3 may be the same as or different from method Φ_U2. For example, request portion computes a passcode using the equation, Φ_U3(G_Ui)= P_Ui. Each passcode, P_Ui, is generated by using a different passcode generator G_Ui. Each new passcode generator, G_Ui+1, is generated from a prior passcode generator, Gui, using method f_U, according to the equation, f_U(G_Ui)=G_Ui+1, for example. Request portion 118 compares passcode P_Ui to passcode P_i, and if passcode P_Ui and passcode P_i are the same, authorization to access to secure entity 103 is granted from request portion 118 of administrator 102, via reply 112, to the user associated with passcode device 101.

0052Methods Φ_U3 and f_U may be the same for all U as long as the passcode generators G_Ui and G_Ui+1 are different. In an embodiment, methods Φ_U3 and f_U are in general different for different U. In an embodiment, for a given authorized user U, Φ_U3, f_U, G_Ui, and G_Ui+1 are the same as Φ₃, f, G_i, and G_i+1, respectively, except that Φ_U3, G_Ui, and G_Ui+1 are generated in association with administrator 102 and Φ₃, f, G_i, and G_i+1 are generated at passcode device 101. Setup portion 116 and request portion 118 may be separate portions of code, such as objects, subroutines, functions, and/or methods. Setup portion 116 and request portion 118 may not be separate portions of code, but may be lines of code intermingled with one another and/or other parts of administrator 102.

0053<figref idref="f0003">FIG. 1C</figref> shows one embodiment of system 100. In the embodiment of <figref idref="f0003">FIG. 1C</figref>, passcode device 101 includes setup' portion 104 and request portion 106, similar to the embodiment of <figref idref="f0002">FIG. 1B</figref>. In the embodiment of <figref idref="f0003">FIG. 1C</figref>, system 100 includes setup 108, request for access 110, reply 112, and administrator 102. Administrator 102 includes API 144, which may include setup API 145, request API 147. Administrator 102 may also include setup portion 156, and request portion 158. As in <figref idref="f0002">FIG. 1B</figref>, in <figref idref="f0003">FIG. 1C</figref> system 100 also includes database 160 and secure entity 103. Request portion 158 may include error handler 120.

0054Passcode device 101, administrator 102, and secure entity 103 were explained in conjunction with <figref idref="f0001">FIG. 1A</figref>. Setup portion 104 (of passcode device 101), request portion 106 (of passcode device 101), setup 108, request for access 110, reply 112, and request for access 110 were also explained above in conjunction with <figref idref="f0002">FIG. 1B</figref>. Setup portion 156, request portion 158, database 160 function in essentially the same manner as setup portion 116, request portion 118, database 122 (<figref idref="f0002">FIG. 1B</figref>). However, setup portion 156, request portion 158, database 160 are numbered differently from setup portion 116, request portion 118, database 122 (<figref idref="f0002">FIG. 1B</figref>), because their locations in <figref idref="f0003">FIG. 1C</figref> are different than in <figref idref="f0002">FIG. 1B</figref>, and consequently their operations may have differences that relate to their different locations.

0055In some applications (e.g., an electronic lock for a car), system 100 may not need a database, because the amount of information being stored is relatively small. Other applications, such as accessing a bank account, may have many users and may require the storing of information associated with system 100 in a database. Some institutions may not mind establishing a new database for storing information associated with system 100 when installing system 100. However, other institutions, such as banks, may already use one or more databases. Institutions that already have at least one database may not be interested in maintaining another separate database for the user information associated with system 100, and may prefer to store the user information associated with system 100 in their current database. API 144, setup API 145, and/or request API 147 may communicate with a database for storing and retrieving user information.

0056To explain API 144, in an embodiment, API 144 is located within administrator 102, and communicates with passcode device 101 and database 160. In an embodiment in which administrator 102 is a human (and in other embodiments), API 144 may be external to the rest of administrator 102. Setup API 145 is the interface through which the user, passcode device 101, or a human administrator setup and/or register new user. Request API 147 is the interface through which a user, passcode device 101, or a human administrator request access to secure entity 103. Setup API 145 and request API 147 may share the same fields for entering data or may use different fields. Similarly, setup API 145 and request API 147 may not be distinct modules, but may be different portions of code within administrator 102 and/or API 144 and may be parts of the same module. Alternatively, the lines of code that make setup API 145 and request API 147 may be intermingled with one another, and/or with the rest of administrator 102. Setup API 145 and request API 147 may be any combination of hardware and software. The software portion of setup API 145 and request API 147 (if present) may be written using any of a number of scripts and/or computer languages such as PHP, JSP, a web interface that calls JavaScript routines, C, Perl, TCL, Pascal, and/or Basic.

0057In an embodiment, setup API 145 and request API 147 may be capable of handling both clients that prefer to use pre-existing database, such as database 160, and those that prefer to use a newly established database, facilitating a quick integration of system 100 into a pre-existing system and thereby reducing the financial costs of integration. In an alternative embodiment, a different setup API 145 and/or request API 147 are used depending upon whether the customer intends on using their own database or allowing administrator 102 to setup a database.

0058To explain setup API 145 in conjunction setup portion 156, setup API 145 may cause user information, such as passcode generators G_Ui to be stored in database 160. Setup API 145 may cause methods Φ_U2 and/or Φ_U3 to be stored within administrator 102 for use by setup portion 156. Methods Φ_U2, Φ_U3, and/or f_U may also be stored within administrator 102 for use by setup portion 156..

0059Request portion 158 may contain proprietary executable code that receives a passcode from request API 147. Request portion 158 may determine whether passcode P_i is valid or not.

0060Regarding database 160, database 160 may have existed prior to the installation of system 100, and may store a variety of different types of information, some of which may have not have any relationship to granting access to the secure entity 103. When configuring system 100 or when setting up a new user, if database 160 already exists and already has a records for the user of interest, system 100 may add a field to the record for a user ID U and for a passcode generator G_Ui. In an alternative embodiment, database 160 is within administrator 102, and is installed with and/or after administrator 102.

0061Putting the together the above discussion of API 144, setup portion 156 and request portion 158, and database 160, a registration code R may be based upon (e.g., copied from or received as) output from passcode device 101 and optionally may also be based on other user information that is entered into the setup API 145. Setup API 145 calls setup portion 156 and passes registration code R as an argument, where registration code R is received by setup portion 156.

0062In an embodiment, setup portion 156 determines if registration code R is valid, and sends a valid or invalid message back to setup API 145. The determination of whether registration code R is valid may be a determination as to whether registration code R fits a particular format. If administrator 102 stores a copy of the user information from which registration code was derived, then the determination as to whether registration code is valid may include generating the registration code at registration portion 156, comparing the generated registration code with the received registration code. Determining whether registration code R is valid may involve verifying that the user associated with registration code R exists, determining whether user ID U is valid, and/or verifying other user information that registration portion 156 has access to. Determining whether registration code R is valid may involve administrator 102 sending a communication to passcode device 101 or the associated user confirming that the registration code was sent. If valid, the setup API 145 also sends a passcode generator G_Ui (generated from registration code R) and may optionally send other user information, such as the user ID U, to database 160.

0063When a user would like to access secure entity 103, a passcode P_i is entered into, transmitted to, and/or received by request API 147 based on output from passcode device 101. Request API 147 calls request portion 158, using passcode P_i as an argument. User ID U may be encoded within passcode P_i, and request portion 158 may extract user ID U from passcode P_i. Request portion 158 may return user ID U to request API 147. If passcode P_i is invalid, request portion 158 may return an invalid user ID U. Alternatively, instead of request portion 158 extracting the user ID U from passcode P_i, the user may enter user ID U into request API 147, or request API 147 may receive user ID U from passcode device 101.

0064Administrator 102 uses user ID U as a database index for the purpose of retrieving passcode generator G_Ui from the database 160. If user ID U is an invalid index, then administrator 102 sends an invalid message to request API 147. If user ID U is a valid index, then the administrator 102 sends passcode generator G_Ui to request API 147. Request API 147 calls request portion 158, and sends two arguments, passcode P_i and passcode generator G_Ui, which are received by request portion 158. Request portion 158 determines whether passcode P_i and passcode G_Ui match. If passcode P_i and passcode G_Ui match, then request portion 158 returns a valid message and the updated passcode generator Gui+i = f(G_Ui) to the request API 147. Administrator 102 stores passcode generator G_i or an updated version of passcode generator G_Ui+1 in database 160, such that passcode generator G_i or its updated version is indexed by user ID U. However, if passcode P_i and passcode generator G_Ui do not match, the request portion 158 returns an invalid message to request API 147. Then request API 147 may send an invalid message to the user U, a human administrator, and/or passcode device 101.

0065<figref idref="f0004 f0005">FIG. 2</figref> shows an example of an embodiment of a secure system 200. Secure system 200 includes passcode device 202, computer 204 having input system 206 and output system 208. Secure system 200 also includes system 210, network 212, system 214, system 216, system 218, and system 220.

0066Secure system 200 illustrates some of the variations of the manners of implementing system 100. Passcode device 202 is one embodiment of passcode device 101. Passcode device 202 is capable of being plugged into and communicating with computer 204 or with other systems via computer 204. Passcode device 202 also may communicate wirelessly with computer 204. A user may use input system 206 and output system 208 to communicate with passcode device 101.

0067Computer 204 is directly connected to system 210, and is connected, via network 212, to system 214, system 216, and system 218, which is connected to system 220. Network 212 may be any one or any combination of one or more Local Area Networks (LANs), Wide Area Networks (WANs), wireless networks, telephones networks, and/or other networks. System 218 may be directly connected to system 220 or connected via a LAN to system 220. Administrator 102 may be any of, a part of any of, or any combination of any of computer 204, system 210, network 212, system 214, system 216, system 218, and/or system 220. Secure entity 103 and may be any of, a part of any of, or any combination of any of system 210, network 212, system 214, system 216, system 218, and/or system 220. For example, administrator 102 may be located on system 214, and secure entity 103 may be located on system 216. As another example, administrator 102 may be located on computer 204, and secure entity 103 may be located on system 210, 214, system 216, system 218, system 220, and/or network 212. As yet another example, administrator 102 and secure entity 103 may both be located on system 216 or may both be located on system 210. As another example, system 218 may be administrator 102, and system 220 may include secure entity 103.

0068<figref idref="f0005">FIG. 2B</figref> shows a block diagram of a computer system 250 used in system 100. Computer system 250 may include output system 252, input system 254, memory system 256, processor system 258, communications system 262, and input/output device 264. In other embodiments, computer system 250 may not include all of the components listed above or include other components in addition to and/or instead of those listed above.

0069Computer system 250 is an example of a system that may be used for any one of, any combination of, or all of computer 204, system 210, system 214, system 216, system 218, and/or system 220.

0070Output system 252 may include any one of, some of, any combination of, or all of a monitor system, a handheld display system, a printer system, a speaker system, a connection or interface system to a sound system, an interface system to peripheral devices and/or a connection and/or interface system to a computer system, an intranet, and/or an internet, for example.

0071Input system 254 may include any one of, some of, any combination of, or all of a keyboard system, a mouse system, a track ball system, a track pad system, buttons on a handheld system, a scanner system, a microphone system, a connection to a sound system, and/or a connection and/or interface system to a computer system, intranet, and/or internet (e.g., IrDA, USB), for example.

0072Memory system 256 may include, for example, any one of, some of, any combination of, or all of a long term storage system, such as a hard drive; a short term storage system, such as random access memory; a removable storage system, such as a floppy drive, jump drive or other removable drive; and/or flash memory. Memory system 256 may include one or more machine-readable mediums that may store a variety of different types of information.

0073The term machine-readable medium is used to refer to any medium capable carrying information that is readable by a machine. One example of a machine-readable medium is a computer-readable medium. Another example of a machine-readable medium is paper having holes that are detected that trigger different mechanical, electrical, and/or logic responses. For example, embedded software is stored on a machine-readable medium. The term machine-readable medium also includes mediums that carry information while the information is in transit from one location to another, such as copper wire, air, water, and/or optical fiber. Software versions of any of the components of <figref idref="f0001 f0002 f0003">FIGs. 1A-C</figref> may be stored on machine-readable mediums.

0074Processor system 258 may include any one of, some of, any combination of, or all of multiple parallel processors, a single processor, a system of processors having one or more central processors, and/or one or more specialized processors dedicated to specific tasks.

0075Communications system 262 communicatively links output system 252, input system 254, memory system 256, processor system 258, and/or input/output system 264 to each other. Communications system 262 may include machine-readable media such as any one of, some of, any combination of, or all of. electrical cables, fiber optic cables, long term and/or short term storage (e.g., for sharing data) and/or means of sending signals through air (e.g., wireless communications), for example. Some examples of means of sending signals through air include systems for transmitting electromagnetic waves such as infrared and/or radio waves and/or systems for sending sound waves.

0076Input/output system 264 may include devices that have the dual function as input and output devices. For example, input/output system 264 may include one or more touch sensitive display screens, which display an image and therefore are an output device and accept input when the screens are pressed by a finger or stylus, for example. The touch sensitive screens may be sensitive to heat and/or pressure. One or more of the input/output devices may be sensitive to a voltage or current produced by a stylus, for example. Input/output system 264 is optional, and may be used in addition to or in place of output system 252 and/or input device 254.

0077<figref idref="f0006">FIG. 3A</figref> shows one example of a passcode device 202. Passcode device 202 includes acquisition mechanism 302, cover 304, and interface 306. In other embodiments, passcode device 202 may not have all of the components listed above or may have other components instead of and/or in addition to those listed above.

0078Acquisition mechanism 302 may be a mechanism of acquiring fingerprints. Cover 304 may be a cover for covering acquisition mechanism 302, and for protecting acquisition mechanism 302 when acquisition mechanism 302 is not in use. Cover 304 may swing open, slide open, and/or snap off and on. Interface 306 is for connecting with an electronic device, such as a computer. Interface 306 may be a USB port, an RS 232 connection, a wireless connection using RFID, a serial port or any of a number of other types of connections.

0079<figref idref="f0006">FIG. 3B</figref> shows an example of a passcode device 350. Passcode device 350 includes display 352, acquisition mechanism 354, and cover 356. In other embodiments passcode device 350 may not have all of the components listed above or may have other components instead of and/or in addition to those listed above.

0080Passcode device 350 is an embodiment of passcode device 101. Passcode device 350 may be used instead of passcode device 202 in <figref idref="f0004">FIG. 2A</figref>. Display 352 displays passcodes and/or registration numbers. Display 352 is an interface with which the user interacts with passcode device 352, and may be used for transferring the passcode or registration code to an administrator. Passcode device 350 may also include a transmitter for transmitting the passcode or registration code via radio waves, light pulses, and/or sound, for example. Acquisition mechanism 354 maybe for acquiring fingerprints and/or images of other parts of the body of the user. The user may swipe her or his finger over acquisition mechanism 354. In response, display 352 may display a passcode that is only good for one use. The user reads the passcode or registration code and causes the passcode and/or registration code to be submitted to an administrator. Cover 356 slides over the portion of passcode device 350 having acquisition mechanism 354 to protect acquisition mechanism 354 from damage when not in use.

0081<figref idref="f0007">FIG. 4</figref> shows an example of a passcode device 400. Passcode device 400 includes display 402, keypad 404, and acquisition mechanism 406. In other embodiments passcode device 400 may not have all of the components listed above or may have other components instead of and/or in addition to those listed above.

0082Passcode device 400 is an embodiment of passcode device 101, which may be used instead of passcode device 202 in <figref idref="f0004">FIG. 2A</figref>. Display 402 may display passcodes, registration numbers, status information, instructions, replies to commands, for example. Passcode device 400 may also include a transmitter for transmitting the passcode or registration code via radio waves, light pulses, and/or sound, for example. Keypad 404 is for entering user information and commands, for example. Acquisition mechanism 406 maybe for acquiring fingerprints and/or images of other parts of the body of the user. Having both keypad 404 and acquisition mechanism 406 allows passcode device 400 to be configured to require that the user enter identifying information, such as social security number and birthday, in addition to the user information acquired via acquisition mechanism 406.

0083<figref idref="f0007">FIG. 5A</figref> shows an example of an embodiment of secure system 500. Secure system 500 includes display 502, keypad 504, acquisition mechanism 506, key 508, and car 510. In other embodiments passcode device 500 may not have all of the components listed above or may have other components instead of and/or in addition to those listed above.

0084Passcode device 500 is an embodiment of passcode device 101. Display 502 may display passcodes, registration numbers, status information, instructions, replies to commands, for example. Keypad 504 is for entering user information and commands, for example. Acquisition mechanism 506 may be for acquiring fingerprints and/or images of other parts of the body of the user. Key 508 may be used as an alternative way of unlocking car 510. The user enters user information via acquisition mechanism 506, and then may choose a particular action or command such as open the driver's door, open all of the doors, open the trunk, lock the driver's door, and/or lock all of the doors.

0085Any one of, or any combination of, passcode devices 350, 400, and 500 maybe used in place of, or in addition to, passcode device 202 within system 200, for example. Passcode devices 202, 350, 400, and 500 are just a few example of the many embodiments of passcode device 101.

0086<figref idref="f0008">FIG. 5B</figref> shows an example of a system 550. System 550 includes at least passcode device 350 and electromechanical lock 552. As in <figref idref="f0006">FIG. 3B</figref>, passcode device 350 includes display 352, acquisition mechanism 354, and cover 356. In other embodiments passcode device 350 may not have all of the components listed above or may have other components instead of and/or in addition to those listed above.

0087Pascode device 350 and its components were described in <figref idref="f0006">FIG. 3B</figref>. In system 550, passcode device 350 opens electromechanical lock 552. In an embodiment, administrator 102 is located within electromechanical lock 552. Passcode device 350 may communicate with electromechanical lock 552 by sending electromagnetic signals that include the passcode to electromechanical lock 552. If the passcode is sent via electromagnetic signals, then display 352 is unnecessary and may not be included. Alternatively, electromechanical lock may include a key pad or other means for manually entering the passcode read off of display 352.

0088<figref idref="f0009">FIG. 6</figref> shows a block diagram of a circuit of an embodiment of the passcode device 101. Passcode device 101 includes passcode circuitry 602, which may include secure area 604, program 605, and user information 606. Passcode device 101 may also include acquisition mechanism 608 and interface 610.

0089Passcode circuitry 602 generates passcodes P_i, registration codes R, passcode generators G_i or G_Ui, and communicates with administrator 102. Passcode circuitry 602 authenticates information acquired from the user and decides whether to generate a passcode, based on the information. Passcode circuitry 602 may implement setup portion 104 request portion 106. Passcode circuitry 602 may include a processor chip. Alternatively, passcode circuitry 602 may send instructions to be processed by a processor associated with computer 204 (<figref idref="f0004 f0005">FIG. 2</figref>) and/or include specialized logic circuits for performing specific functions.

0090Passcode circuitry 602 may execute software instructions or perform similar functions, such as acquiring user information which may include a fingerprint (or other user information) from a sensor, matching acquired user information (e.g., an acquired fingerprint) against a stored user information extracted form other user information (e.g., fingerprint information extracted from a fingerprint), sending communication and control commands to a display, and/or encrypting the registration code R and transmitting the encrypted registration code R to the administrator 102 when the user and administrator 102 are not in the same physical location. By including a processor or an equivalent specialized logic circuit as part of passcode circuitry 602 in passcode device 101 the security is enhanced, because external processors are given fewer chances to inspect the contents of passcode device 101.

0091Alternatively, passcode circuitry 602 may only store software instructions that are run by an external processor, and the external processor gives instructions to cause the acquisition of user information, the encryption of user information, and/or the generation of the passcode, for example. Alternatively, a specialized logic circuit is included in passcode circuitry 602 that carries out the functions that the software causes the processors to perform. Passcode circuitry 602 may include memory.

0092Secure area 604 may be a portion of passcode circuitry 602 that uses embedded software. Secure area 604 may be memory that is onboard, or partially onboard, passcode circuitry 602. In some embodiments, the secure area 604 includes at least some memory that is onboard passcode circuitry 602. For example, in an embodiment in which passcode circuitry 602 includes a processor chip, secure area 604 may include cache associated with the process and/or other memory onboard the processor chip. For example, secure area 604 may store fingerprint templates, details of fingerprints, and/or copies of images of fingerprints on secure area 604. Some of secure area 604 may be non-volatile. The use of non-volatile memory enables the device to permanently store code generation information, user information (such as fingerprint information), executable code, and/or registration codes, for example.

0093In yet another embodiment, user information is used to generate registration code R, passcode generator G_i, and/or passcodes P_i within secure area 604. Secure area 604 may store method f, method Φ₁, method Φ₂, and/or method Φ₃. The use of fingerprints or other user information to create passcodes within secure area 604 or the use of fingerprints or other user information instead of passcodes within a secure area eliminates or reduces the need to memorize and store passcodes in an insecure system.

0094Program 605 is executed by passcode circuitry 602. Program 605 may be the embedded software that runs within secure area 604. Program 605 is an example of an executable program that may stored in secure area 604. In an embodiment, there is no operating system on passcode device 101. In an alternative embodiment, there is an operating system. By executing program 605 (e.g., software for handling fingerprints or other user data) in a secure embedded device, the fingerprints are less susceptible to theft; the fingerprints are not transmitted to the insecure device, nor is there any need to have encrypted templates of the fingerprints transmitted to an insecure device.

0095User information 606 may also be stored in secure area 604. User information 606 may include, or may be information derived from, any of the forms for user information and identifying information discussed above (e.g., fingerprints, iris scans, etc.), registration code R, method f, method Φ1, method Φ₂, and/or method Φ₃, and/or passcode generator G_i. Storing passcode generator G_i in secure area 604 may facilitate quickly generating a one-time passcode, because the user does not need to wait for passcode generator G_i to be generated.

0096The security of the passcode circuitry 602 may be enhanced by any one of, any combination or of, or all of (1) the use of embedded software, such as program 605, (2) the lack of an operating system, and (3) secure area 604 being at least part of a self-contained device not connected to a computer or the internet. For example, the unit that includes secure area 604 may contain its own processor as passcode circuitry 602. In an embodiment, the secure area 604 may not have any of these security enhancing features.

0097Acquisition mechanism 608 acquires information that is used by passcode circuitry 602 during the process of generating passcodes. Although not necessary, in some embodiments, acquisition mechanism 608 and passcode circuitry 602 could be integrated into a single chip. Alternatively, acquisition mechanism 608 and passcode circuitry 602 may be two separate chips. The user information acquired by acquisition mechanism 608 or user information derived from user information acquired by acquisition mechanism 608 may be stored in secure area 604. Acquisition mechanism 608 may acquire information that is used to identify a user. The information acquired by acquisition mechanism 608 may be used by passcode circuitry 602 for authenticating or identifying a user as a prerequisite for granting a passcode. For example, acquisition mechanism 608 may acquire fingerprints, details of fingerprints, copies of images of fingerprints, and/or other user information. Acquisition mechanism 608 may include a fingerprint sensor that enables passcode device 101 to scan fingerprints. Acquisition mechanism 608 may include a area sensor or a sweep sensor, for example. In an embodiment, acquisition mechanism 608 is capable of acquiring fingerprints and authenticating a newly acquired fingerprint.

0098In an embodiment, interface 610 is a display, such as display 352 (<figref idref="f0006">FIG. 3</figref>), display 402 (<figref idref="f0007">FIG. 4</figref>), and display 502 (<figref idref="f0007">FIG. 5A</figref>). In another embodiment, interface 610 interfaces with hardware associated with administrator 102 and/or secure entity 103. Passcode circuitry 602 sends instructions and/or other signals, via interface 610 to administrator 102 and/or secure entity 103 or to hardware associated with secure entity 103. Interface 610 may draw power from hardware associated with secure entity 103, which is used to power the operations of passcode device 101. Optionally, for example, interface 610 may be a USB port, serial port, a parallel port, and/or other connection.

0099<figref idref="f0010">FIG. 7</figref> shows a flowchart of and example of a method for setting up passcode device 101. During step 702, identifying information T is acquired by passcode device 101. For example one or more fingerprints, one or more images of the face, one or more images of eyes, or other pieces of identifying information T are acquired. Optionally, information may be extracted from the identifying information. Optionally, identifying information T is also acquired by administrator 102. For example, administrator 102 may be associated with a bank, and the bank may require that the user visit the bank so that the identifying information T (e.g., fingerprints) can be acquired in person. During step 704, one or more unique registration codes R are generated from the one or more of the fingerprints, which may be generated according to the equation Φ₁(T)=R. In an embodiment, during step 704, in the secure area 604 of the passcode device 101, fingerprint information obtained from the user is passed to method Φ₁, which may be a one-way function or another method of encoding that generates a registration code, R.

0100During step 706, registration code R is securely given to administrator 102. Registration code R is created during step 704, and securely given to administrator 102 during step 706. The registration code R may be given to administrator 102 in the same physical place, such as at a bank, or registration code R may be mailed or electronically transmitted to administrator 102 if the setup is accomplished remotely. In some applications, registration code R may be encrypted first and then electronically transmitted or sent by mail. In the embodiment in which administrator 102 is associated with an entity that has acquired identifying information T, administrator 102 causes the identifying information to be authenticated, thereby verifying that the user is legitimate. Optionally, registration code R is stored and indexed by administrator 102 according to user ID U, as R_U. Alternatively, even if identifying information T is not collected by administrator 102, other information may be checked to determine the validity of registration code R. For example, other identifying information may be sent with registration code R or the format of registration code R may checked to determine whether registration code R is valid.

0101During step 708, an initial passcode generator G₁ is created and stored in flash memory, a cache, or other memory of the processor contained in the secure area 604 (<figref idref="f0009">FIG. 6</figref>) of passcode device 101. Initial passcode generator G₁ may be created according to equation Φ₂(R)=G₁. Initial passcode generator G₁ may then be stored for later use in generating an initial passcode P₁ according to P₁ = Φ₃(G₁). During this later use of initial passcode generator G₁ after generating passcode P₁a, passcode P₁ is subsequently transmitted to the host (e.g., administrator 102) for authentication. In this embodiment, passcode P₁ is not stored at passcode device 101, but is created just prior to being used and then discarded just after being used to reduce the chance of passcode P₁ being stolen. In an alternative embodiment, passcode P₁ can generated immediately after generating passcode generator G₁ and then passcode P₁ can also be stored in secure area 604 of the processor to reduce execution time at passcode device 101..

0102Similarly, at administrator 102, the initial passcode generator G₁ is created and stored. Optionally, as part of storing initial passcode generator G₁, initial passcode generator G₁ is indexed according to a user ID U as G_U1. Similarly, each subsequent passcode generator G_i may be stored and indexed according to user ID U, as Gui. In this embodiment, passcode P₁ is not stored at admiistrator 102, but is created just prior to being used and then discarded just after being used to reduce the chance of passcode P₁ being stolen. In an alternative embodiment, passcode P₁ can generated at administrator 102 immediately after generating passcode generator G₁ and then passcode P₁ can also be stored in database 122 or 160 to reduce execution time at administrator 102. In other embodiments, method 700 may not have all of the steps listed above or may have other steps instead of and/or in addition to those listed above. Additionally the steps of method 700 may not be distinct steps.

0103<figref idref="f0011">FIG. 8</figref> shows a flowchart of an example of a method 800 of generating a passcode. In step 802, the passcode generator G_i is retrieved from a secure area 604 (<figref idref="f0009">FIG. 6</figref>). In the notation of this specification, if this is the first time passcode device 101 is being used after registration, the index i is equal to 1, passcode generator G_i is the initial passcode generator G₁. In step 804, a method Φ₃ is applied to passcode generator G_i, denoted as Φ₃(G_i), to create passcode P_i. In other words, P_i = Φ₃ (G_i).

0104In step 806, the passcode generator G_i is changed to a new value G_i+1, where G_i+1 is set equal to the new value f(G_i). There are an infinite number of functions that f could be. The method f may be referred to as a perturbing method (e.g., a perturbing function). One possible perturbing method f could add Φ₃(G_i) to G_i. Another possible perturbing function could be f(G_i) = Φ₃(G_i + Φ₃(G_i)). More generally, the perturbing function could be f(G_i) = (Φ(G_i) ^∗ G_i) or f(G_i) = Φ(G_i^∗ Φ(G_i) ), where "*" may be any operator. For example, "*" may be binary operators such as +, -, OR, NOR AND, NAND, XOR, , NOT(XOR). Another possible perturbing method f could consider passcode generator G_i as a number and add 1. Another possible perturbing method f could increase passcode generator G_i by 2. Another possible perturbing method f could add 1 to passcode generator G_i and permute the order of the symbols in passcode G_i using some randomly chosen permutation. Even another possible perturbing method f could add 1 to passcode generator G_i, and then permute the bits in passcode generator G_i. Passcode generator G_i could be used as a seed for a random number generator, which is used as f to generate G_i+1. Steps 804 and 806 may be performed concurrently or in any order with respect to one another. Step 806 may be performed at anytime after step 802.

0105In step 808, a passcode P_i (e.g., a one time passcode) is either transmitted to a display or submitted directly to administrator 102. During transmission, in some cases P_i can be encrypted for additional security, for example in a wireless transmission. There are many different methods for transmitting the passcode P_i to the administrator 102. In one method, passcode P_i can be displayed to administrator 102 (e.g. if administrator 102 is a human being or if administrator 102 includes a scanner that can scan the display) when the user is in the same physical location as administrator 102. In a second method, the user may transmit passcode P_i over the phone (e.g., via a phone call and human voice or via a modem and an electronic signal). In a third method, the user may submit the passcode P_i using the Internet. The user may submit the passcode P_i by other electronic means such as a fax machine or an ATM machine. Step 808 may be performed anytime after step 804. Steps 806 and 808 may be performed concurrently or in any order with respect to one another.

0106<figref idref="f0012">FIG. 9</figref> shows a flowchart of a method 900 of authenticating a passcode P_i. Method 900 is performed in response to step 808 of method 800 (<figref idref="f0011">FIG. 8</figref>). In step 902, administrator 102 enters or receives passcode P_i from the user. In an embodiment in which administrator 102 causes passcode generator G_i to be indexed according to user ID U, step 902 may include at least two parts, which are step 904 and 906. In step 904, passcode P_i is received, and in step 906 user ID U is received. User ID U and passcode P_i may be sent as two separate sequences of bits. Alternatively, user ID U and passcode P_i may be sent as one sequence of bits in which user ID U is encoded within passcode P_i. If User ID is encoded within passcode P_i, then receiving user ID U includes extracting user ID U from P_i. In another embodiment, passcode P_i and user ID U may be concatenated together or otherwise encoded within the same sequence of bits. Step 906 is optional, and passcode P_i may be sent without any user ID.

0107In step 908, user ID U is associated with a passcode generator G_Ui, and passcode generator G_Ui is retrieved. Alternatively, in an embodiment in which passcode generators G_i are not indexed according to user ID U, for example, a set of all possible passcode generators G_i may be retrieved. In step 910, for each passcode generator G_i in the database, a method Φ₃ is applied to passcode generator G;, denoted as Φ₃(G_i), and Φ₃(G_i)= P_Ui is compared to passcode P_i. Alternatively, if the passcode generators are indexed, the passcode generator G_Ui that is associated with user ID U, a method Φ₃ is applied to passcode generator G_Ui, denoted as Φ₃(G_Ui), and Φ₃(G_Ui)= P_Ui is compared to passcode P_i.

0108In step 912, if the passcode generators are indexed, a decision is made as to whether Φ₃(G_Ui) equals passcode P_i. If the passcode generators are not indexed, a decision is made as to whether there is any Φ₃(G_i) that equals passcode P_i. If Φ₃(G_Ui) equals passcode P_i or if there is a Φ₃(G_i) that equals passcode P_i, then the passcode P_i submitted by the user is valid, method 900 continues with step 914. In step 914, access to secure entity 103 is granted. Next, in step 916, the value stored for the passcode generator is set equal to a new value G_Ui+1 = f(G_Ui) or G_i+1 = f(G_i), where f is a method, which may be one of the infinite number of perturbing methods (e.g., perturbing functions), as discussed above. If the passcode generators G_i are not indexed according to user ID, the method f is applied only to the passcode generator that matched the submitted passcode P_i. After step 916, method 900 terminates.

0109Returning to step 912, if Φ₃(G_Ui) does to equal P_i or if there is no Φ₃(G_i) that equals P_i, then the passcode P_i submitted by the user is invalid, method 900 continues with step 918 where access is not granted. After step 918, in optional step 920 a further check is performed to see if P_i is valid in case there was a human error. Step 920 is discussed further in conjunction <figref idref="f0013">FIG. 10</figref>. If step 920 is not included in method 900, then step 918 may also include sending a message to the user that passcode P_i is invalid.

0110<figref idref="f0013">FIG. 10</figref> shows a flowchart of an example of a method for carrying out step 920 of method 900. In step 1002 an initial trial passcode generator, G_TUi, is computed according to f(G_Ui)=G_TUi. In other words, if the user generated a passcode P_i, but never submitted passcode P_i, then the value of passcode generator G_i at passcode device 101 will be different from passcode generator G_Ui or the set of passcode generators G_i at administrator 102. Consequently, one manner for correcting this problem is to advance the value of passcode generator G_Ui or of the set of passcode generators G_i to that of the next index value of i, which is accomplished by applying the perturbing method to the current value of passcode generator G_Ui or of the set of passcode generators G_i. If the passcode generators are not indexed according to user, then the perturbing method needs to be applied to all of the current values of passcode generator G_i to obtain a set of initial trial passcode generators G_Ti.

0111Next, in step 1004, for trial passcode generator G_TUi or for each trial passcode generator G_Ti a trial passcode P_TUi or a set of trial passcodes P_Ti are generated according to Φ₃(G_TUi)=P_TUi or Φ₃(G_Ti)=P_Ti. In step 1006, P_i is compared to each of the P_Ti or P_TUi. If passcode P_TUi matches passcode P_i or if there are any trial passcodes P_Ti that match passcode P_i, then step 920 proceeds to step 1008, where access is granted. As part of step 1008, the value of a trial passcode generator G_TUi is updated, and the updated value of trial passcode generator G_TUi+1 is used to replace passcode generator G_Ui or the updated value of trial passcode generator G_Ti+1 is used to replace the passcode generator of the set of passcode generators G_i from which trial passcode generator G_Ti+1 was generated. After step 1008, step 920 terminates.

0112Returning to step 1006, if passcode P_TUi does not match passcode P_i or if there are no trial passcode P_Ti that match passcode P_i, then step 920 proceeds to step 1010, where a determination is made as to whether the maximum number of trials has been reached. In other words, it is possible that the user generated multiple passcodes P_i and consequently passcode generator G_Ui or one of the set of passcode generators G_i associated with administrator 102 may lag the value of passcode generator G_i at passcode device 101 by several values of index i. Consequently, step 920 may try several applications of perturbing method f before deciding that passcode P_i is invalid. Thus, step 920 may be configured for applying f up until a maximum number of trials. If that maximum has been reached without finding a match, then step 920 proceeds from step 1010 to step 1012, and access is not granted. After step 1012, step 920 terminates.

0113Returning to step 1010, if the maximum number of trials has not been reached, then step 1010 proceed to step 1014 where the perturbing method f is applied to the trial passcode generator G_TUi or trial set of passcode generators G_Ti according to f(G_Ti)=G_Ti+1 or f(G_UTi)=G_UTi+1 Next in step 1016, a new passcode P_UTi+1 or set of passcodes P_Ti+1 are generated according to Φ₃(G_Ti)=P_Ti+1 or Φ₃(G_UTi)=P_UTi+1 After step 1016, step 1006 is repeated. Steps 1006, 1010, 1014, and 1016 are repeated until either the maximum number of trials is reached and access is not granted in step 1012 or until a match trial passcode is found, and access is granted in step 1008.

0114<figref idref="f0014">FIG. 11</figref> shows a flowchart of an example of a method 1100 for registering a user. Method 1100 is an embodiment of, or may be used as a replacement for, steps 704 and 706 of method 700. In step 1102, the registration code, and optionally other user information, is entered into, transmitted to, and/or received by setup API 145 (<figref idref="f0003">FIG. 1C</figref>), based on output from passcode device 101. In response, in step 1104 setup API 145 calls setup portion 156 (<figref idref="f0003">FIG. 1C</figref>) located in administrator 102 (<figref idref="f0003">FIG. 1C</figref>), and passes registration code R as an argument to setup portion 156 in administrator 102. In step 1106, setup portion 156 determines whether the registration code R is valid. If setup portion 156 determines that registration code R is invalid, method 1100 proceeds to step 1108. In step 1108, a message is sent to setup API 145 that registration code R is invalid. After step 1108, method 1100 terminates. Returning to step 1106, if setup portion 156 determines that registration code R is valid, method 1100 proceeds to step 1110. In step 1110, setup portion 156 sends a passcode generator G_Ui or G_i and a message back to setup API 145 that registration code R is valid. Setup portion 156 may also send other information to setup API 145, such as user ID U or other information.

0115Next, in step 1112, if the registration code R is valid, then setup API 145 transmits arguments, the passcode generator G_Ui or G_i and optionally user ID U (which may be used as a database index) to database 160. Optionally, other user information may also be sent to database 160. In other embodiments method 1100 may not have all of the steps listed above or may have other steps instead of and/or in addition to those listed above. Additionally the steps of method 1100 may not be distinct steps.

0116<figref idref="f0015">FIGs. 12A</figref> and <figref idref="f0016">12B</figref> show a flowchart of an example of a method 1200 for authenticating a passcode at administrator 102. Method 1200 is an alternative to method 900. In step 1202, a passcode P_i is received by request API 147. For example, passcode P_i is entered into request API 147 or transmitted to request API 147. In step 1204, administrator 102 retrieves P_i from its request API 147. In step 1206, administrator 102 places user ID U in request API 147. In step 1208, request API 158 sends user ID U to database 160. In step 1210, database 160 decides whether user ID U is valid. Database 160 attempts to retrieve passcode generator G_Ui or G_i by looking up user ID U. Database 160 may discover that user ID U does not exist, and therefore is invalid. If user ID U is invalid, then method 1200 proceeds to step 1212. In step 1212, administrator 102 sends an invalid message to request API 147. After step 1212, method 1200 ends. Returning to step 1210, if user ID U is valid, then method 1200 proceeds to step 1214 where administrator 102 sends passcode generator G_Ui to request API 147. Next, in step 1216, request API 147 calls request portion 158, and sends two arguments, passcode P_i and passcode generator G_Ui to determine whether passcode P_i and passcode generator G_Ui match.

0117In step 1218, request portion 158 determines whether passcode P_i and passcode generator G_Ui match. In general, the output of Φ₃(G_Ui) is a sequence of bytes and each of these bytes may be a value ranging from 0 to 255. Thus, P_i and G_Ui match if P_i = Φ₃(G_Ui).

0118Step 1218 may also include applying an error handling routine, such as method 1000 (<figref idref="f0013">FIG. 10</figref>), prior to concluding that passcode P_i and passcode generator G_Ui do not match. Thus, a determination that passcode P_i and passcode generator G_Ui match may involve one or more prior determinations that passcode P_i and trial passcode generator G_UTi do not match.

0119If passcode P_i and passcode generator G_Ui match, then method 1200 proceeds to step 1220. In step 1220 request portion 158 updates G_Ui according to f(G_Ui) = G_Ui+1 , returns the updated passcode generator G_Ui+1 and a message that passcode P_i is valid to request API 147. In step 1222, request API 147 calls administrator 102, and sends a message that passcode P_i is valid, and sends the updated passcode generator G_i+1 as an argument. Optionally, user ID U is also sent to administrator 102. In step 1224, administrator 102 causes updated passcode generator G_i+1 to be stored in database 160, indexed by user ID U. After step 1224, method 1200 is terminated.

0120Returning to step 1218, if passcode P_i and passcode generator G_Ui do not match, the method proceeds to step 1226. In step 1226, the request portion 158 returns an invalid message to request API 147. Next, in step 1228, request API 147 calls administrator 102, and sends a message that passcode P_i is invalid. After step 1228, method 1200 terminates. In other embodiments method 1200 may not have all of the steps listed above or may have other steps instead of and/or in addition to those listed above. Additionally the steps of method 1200 may not be distinct steps.

0121<figref idref="f0017">FIG. 13</figref> is a flowchart of an example of method of installing system 100. In step 1302 the administrator is installed. For example, administrator 102 may be installed on a computer that is separate from secure entity 103. If the system on which system 100 is being installed has other software, the administrator may be integrated into that software or may be installed as a separate software module. Installing administrator 102 may involve installing setup portion 116 or 156 and request portion 118 or 158. In optional step 1306, an API is installed. In an embodiment, step 1306 may involve installing a request API 147 and a setup API 145. In step 1308, an offer is made to allow the installer to choose whether to use a preexisting database. If the choice of using a preexisting data is chosen, in step 1310 the API is configured to communicate with the database. Step 1310 may involve adding to database 160 a field for storing passcode generators to each user record. Step 1310 may additionally involve adding a field for a user ID U to each user record. For example, database 160 may not have field for user IDs or may use different user IDs than system 100. Of course, database 160 may have two fields for user IDs - one field in a location where system 100 is configured for accessing, and another which system 100 is not configured to access. Alternatively, the database may already have a field for a user ID, and the same user ID is used for system 100. Returning to step 1308, if a choice is made to not use any preexisting database, then in step 1312, a database, a file, part of a file, or part of a database is setup for storing passcode generators, which may be indexed according to a user ID. In an embodiment, the passcode generators are not indexed according to user ID. In other embodiments, method 1300 may not have all of the steps listed above or may have other steps instead of and/or in addition to those listed above. Additionally, steps 1302, 1304, 1306, and 1308 may be performed concurrently or in any order with respect to one another. Steps 1310 and 1312 may be performed any time after step 1308, but otherwise may be performed in concurrently or in any order with respect to steps 1302, 1304, and 1306. Additionally the steps of method 1300 may not be distinct steps.

0122<figref idref="f0018">FIG. 14</figref> is a flowchart of an example of a method 1400 for assembling passcode device 101. In step 1402, passcode circuitry 602 (<figref idref="f0009">FIG. 6</figref>) is assembled, which may include installing onboard memory (e.g., secure area 604). In step 1404, the acquisition mechanism 608 (<figref idref="f0009">FIG. 6</figref>) is coupled to the passcode circuitry 602. In step 1406, interface 610 (<figref idref="f0009">FIG. 6</figref>) is coupled to passcode circuitry 602. In step 1408, an embedded program (e.g., program 605) is configured for generating registration codes R, passcode generators G_i, and passcodes P_i, and for using the onboard memory for work space and for storing passcode generators. In step 1410, passcode circuitry 602, acquisition mechanism 608, and interface 610 are enclosed within a housing that is small enough to fit within a user's hand (e.g., shorter than a typical pen and no more than a two or three times wider than a typical pen). For example, the housing may be 2 to 6 inches long and less than a half inch in diameter. The passcode device 101 may be of a size that is comparable to a thumb print. In other words, passcode device 101 only need to be large enough to accept user information. In embodiments where the user information is fingerprints, the passcode device 101 could be the size of a portion of a thumb large enough to capture a thumb print during a swipe, for example. In embodiments where acquisition mechanism is a camera, passcode device 101 does not need to be much larger than a small camera. In an embodiment, passcode device 101 is less than 6 inches, less than 2 inches, less than an inch, or less than a centimeter in size. In other embodiments method 1400 may not have all of the steps listed above or may have other steps instead of and/or in addition to those listed above. Additionally, the steps of method 1400 may be performed in other orders, may not be distinct steps, and/or many of the may be performed concurrently with one another. Additionally the steps of method 1400 may not be distinct steps.

0123A particular application of system 100 is a child identity program. System 100 enables the government to identify a child with a unique registration code R or with a passcode P_i, which is never stored anywhere. For example, the FBI can store a database of registration codes R, but a database intruder would not have access to the biometric data, social security number, or other data of any child. Alternatively, the FBI can store a database of generators G_i, which change each time a new passcode P_i is submitted. Consequently, in addition to the database intruder not having access to the biometric data of any child, the information stolen (passcode generator G_i) is of little use to the intruder in identifying the child, because passcode generator G_i changes periodically, such as with each legitimate access of the data. Similarly, no authorized FBI employee would have access to the biometric data of any child. Consequently, the passcode generator helps act as a child ID for safety, yet also protects private information about the child.