Technical Field
This patent discloses techniques for securing payment devices, and more specifically to methods and apparatuses for securing payment cards against external monitoring attacks. This patent also discloses methods and apparatuses for increasing the leak-resistance of a portable cryptographic token.
Description of the Background Art
Attackers who gain access to cryptographic keys and other secrets can potentially perform unauthorized operations or forge transactions. Thus, in many systems, such as smartcard-based electronic payment schemes, secrets need to be protected in tamper-resistant hardware. However, recent work by Cryptography Research has shown that smartcards and other devices can be compromised if information about cryptographic secrets leaks to attackers who monitor devices external characteristics such as power consumption or electromagnetic radiation.
In both symmetric and asymmetric cryptosystems, secret parameters should be kept confidential, since an attacker who compromises a key can decrypt communications, forge signatures, perform unauthorized transactions, impersonate users, or cause other problems. Methods for managing keys securely using physically secure, well-shielded rooms are known in the background art and are widely used today. However, previously known methods for protecting keys in low-cost cryptographic devices are often inadequate for many applications, such as those with challenging engineering constraints (cost, size, performance, etc.) or that require a high degree of tamper resistance. Attacks such as reverse-engineering of ROM using microscopes, timing attack cryptanalysis (see, for example, P. Kocher, “Timing Attacks on Implementations of Diffie-Hellman, RSA, DSS, and Other Systems,” Advances in Cryptology-CRYPTO '96, Springer-Verlag, pages 104-113), and error analysis (see, for example, E. Biham and A. Shamir, “Differential Fault Analysis of Secret Key Cryptosystems,” Advances in Cryptology-CRYPTO '97, Springer-Verlag, 1997, pages 513-525) have been described for analyzing cryptosystems.
Key management techniques are known in the background art for preventing attackers who compromise devices from deriving past keys. For example, ANSI X9.24, “Financial services—retail management” defines a protocol known as Derived Unique Key Per Transaction (DUKPT) that prevents attackers from deriving past keys after completely compromising a device's state. Although such techniques can prevent attackers from deriving old keys, they have practical limitations and do not provide effective protection against external monitoring attacks in which attackers use partial information about current keys to compromise future ones.
Cryptography Research has also developed methods for using iterated hashing operations to enable a client and server to perform cryptographic operations while the client protects itself against external monitoring attacks. In such methods, the client repeatedly applies a cryptographic function to its internal secret between or during transactions, such that information leaked in each of a series of transactions cannot be combined to compromise the secret. However, the system described has a disadvantage in that the server must perform a similar sequence of operations to re-derive the symmetric session key used in each transaction. Thus, in cases such as where there are a large number of unsynchronized server devices (such as electronic cash applications where a large number of merchant terminals operate as independent servers) or if servers have limited memory, the server cannot reliably precompute all possible session keys clients might use. As a result, transaction performance can suffer since a relatively large number of operations may be required for the server to obtain the correct session key. For example, the n-th client session key can require n server operations to derive. A fast, efficient method for obtaining leak-resistant and/or leak-proof symmetric key agreement would thus be advantageous.
This patent describes ways to make smartcards (and other cryptographic client devices) secure even if attackers are able to use external monitoring (or other) attacks to gather information correlated to the client device's internal operations. In one embodiment, a cryptographic client device (e.g., a smartcard) maintains a secret key value as part of its state. The client can update its secret value at any time, for example before each transaction, using an update process that makes partial information that may have previously leaked to attackers about the secret no longer (or less) usefully describe the new updated secret value. (Information is considered useful if it can help or enable an attacker to implement an actual attack.) Thus, the secret key value is updated sufficiently frequently (perhaps as often as once per transaction) such that information leaked about the input state does not as usefully describe the updated state. By repeatedly applying the update process, information leaking during cryptographic operations that is collected by attackers rapidly becomes obsolete. Thus, such a system can remain secure against attacks involving repeated measurements of the device's power consumption or electromagnetic characteristics, even when the system is implemented using leaky hardware and software (i.e., that leak information about the secret values). (In contrast, traditional systems use the same secret value repeatedly, enabling attackers to statistically combine information collected from a large number of transactions.)
The techniques disclosed herein can be used in connection with a client and server using such a protocol. To perform a transaction with the client, the server obtains the client's current transaction counter (or another key index value). The server then performs a series of operations to determine the sequence of transformations needed to re-derive the correct session key from the client's initial secret value. These transformations are then performed, and the result is used as a transaction session key (or used to derive a session key).
A sequence of client-side updating processes can allow for significant improvements in the performance of the corresponding server operations, while maintaining leak-resistant and/or leak-proof security characteristics in the client device. In one embodiment, each process in the sequence is selected from among two forward cryptographic transformations (FA and FB) and their inverses (FA−1 and FB−1). Using methods that will be described in detail below, such update functions are applied by the client in a sequence that assures that any single secret value is never used or derived more than a fixed number of times (for example, three). Furthermore, the update functions and sequence also assure that the state of (and hence the secret session key value used in) any transaction is efficiently derivable from a starting state (such as the state used in the first transaction) within a small number of applications of FA and FB (or their inverses).
If the number of operations that can securely be performed by a client is n (i.e., n different transactions can be performed, without using the same secret value more than a fixed number of times), a server knowing or capable of obtaining the client's initial secret value K (or initial state corresponding thereto) can derive any resulting secret value (or corresponding state) in the series of transactions significantly faster than by performing n corresponding updates. Indeed, the state for any given transaction can often be derived by a server using 0(log n)calculations of FA and FB (or their inverses). If the system designer has made n sufficiently large, this can allow a virtually limitless set of transactions to be performed by clients while providing excellent server performance.
Indexed Key Management
The techniques disclosed herein can enable parties to perform cryptographic operations with increased security against external monitoring attacks. Although exemplary embodiments are described involving two parties, a “client” and a “server”, the terms “client” and “server” are chosen for convenience and might not necessarily correspond directly to any particular role in a system design. For example, the client could be a smartcard, and the server could be a mainframe computer, or vice versa. Furthermore, although most cryptographic operations involve two parties (e.g., one at the client and one at the server), the techniques can, of course, be applied in environments involving only one party (such as in secure memory or storage systems in which both client and server are under a single party's control or are combined in a single device) or in environments involving more than two parties and/or devices.
In an exemplary embodiment, the client is initialized with a secret key K0 for a symmetric cryptosystem, where K0 is also known to (or derivable by) the server. The key K0 is usually (but not necessarily) specific to a particular client device or party. The client also has a (typically non-secret) index or transaction counter C, which may be initialized to zero. An additional parameter is an index depth D. The value of D may also be non-secret, and (for example) may be client-specific or may be a system-wide global constant. The value of D determines the cycle length of the key update process.
Each of the boxes in the figure represents a value of the secret value (KC). Thus, multiple dots in a box represent different states sharing the same secret value KC. The top row (row 0) of the figure contains one box, which corresponds to the initial state K0 110 as well as subsequent states K30 140 and K60 170, all of which share the same secret value KC. The next row (row 1) contains two boxes, the left of which corresponds to a trio of states (K1 111, K15, and K29) sharing the same secret value, and the right box in the second row corresponds to a second trio of states (K31, K45, and K59) sharing yet another secret value. Similarly, row 2 contains four boxes, representing a total of twelve states of which 4 trios each share among themselves the same secret value. More generally, in this exemplary embodiment, row N (where N<D−1) contains 2N boxes (or unique secret values) and 3(2N) states, and the last row (N=D−1) contains 2N boxes and 2N states. The thicker (curved) path diagrams the process by which the states are updated, starting from the initial state 110 and continuing through to the final state 170. As the states are updated, counter C is also updated (by one for each update).
The exemplary state update processes involve two functions (FA and FB), and their inverses (FA−1 and FB−1), for a total of four functions. At step 100, the client is initialized or personalized with a starting counter C=0 and a starting state having a starting secret value KC=K0. At step 110, the device performs the first transaction, using KC (or a key derived from KC). The key can be used in virtually any symmetric cryptographic transaction. (For example, such a transaction could involve, without limitation, computing or verifying a MAC (Message Authentication Code) on a message, encrypting or decrypting a message, producing a pseudorandom challenge value, deriving a key, etc. Examples of messages include, without limitation, data specifying the amounts of funds transfer operations, e-mail messages, challenge/response authentication data, parameter update authorizations, code updates, audio messages, digitized images, etc.)
After step 110, the client device's secret value KC is updated by applying the function FA and the counter C is incremented, i.e. by performing C←C+1 and KC←FA(KC). (Thus, at step 111, C=1 and KC=FA(K0).). The updated value of KC is used to perform a transaction at step 111. After step 111, C is incremented again and FA is again applied to KC, i.e. by performing C←C+1 and KC=2←FA(KC), yielding the secret key used at step 112. The same pair of operations (C←C+1 and KC←FA(KC) are similarly applied between steps 112 and 113, and between steps 113 and 114.
The transaction at step 115 should use the same value of KC as did the transaction at step 113, since steps 113 and 115 are shown in the same box. Thus, after the transaction at step 114 the update process is performed by computing C←C+1 (yielding C=5) and KC=5←FA−1(KC). Note that KC=5=FA−1(KC=4)=FA−1(FA(KC=3))=KC=3. Thus, the value of KC used at step 115 is the same as the value used at step 113. After the transaction at step 115, KC is updated using function KB by incrementing C and computing KC=6←FB(KC). After the transaction at step 116, the secret value for transaction 117 is computed by applying the function FB−1 to KC.
The update process operates such that after each transaction, a key state update process is performed. The key update involves incrementing C and applying one of the functions FA, FB, FA−1, or FB−1 to the state KC. The use of invertable functions allows a first state and a second state to share the same secret value, where the first state precedes entry into a child (lower level) box from a parent (upper level) box, and the second state is created by reentry into the parent box from the child box. Further, the multiplicity of functions (e.g., FA and FB in the exemplary embodiment) allows the creation of multiple child boxes from each parent box and, hence, a large number of allowable states before the sequence is exhausted (e.g., at end state 190). In going from one particular state to another particular state, the choice of functions (e.g., in the exemplary embodiment of
Eventually, the client may reach a point at which the entire table has been traversed. For example, the end of the process of
(In the example with D=5, there can thus be 26−3=61 transactions.) By choosing a sufficiently large value for D, a system designer can make the maximum number of transactions so large that the “end” will never be reached. For example, D=39 will allow more than 1 trillion (1012) transactions without repeating.
Client-Side Indexed Key Update
For the exemplary embodiment of
At step 230, the device tests whether the variable V is equal to the quantity 2N−3. If equal, function FA−1 should be applied, and processing proceeds to step 235 where the device increments C and updates KC by computing KC←FA−1(KC). Otherwise, at step 240, the device tests whether the variable V is equal to the quantity 2(2N−2). If equal, function FB−1 should be applied, and processing proceeds to step 245 where the device increments C and updates KC by computing KC←FB−1(KC). Otherwise, at step 250, the device tests whether the variable V is equal to zero. If equal, function FA should be applied, and processing proceeds to step 255 where the device increments C and updates KC by computing KC←FA(KC). Otherwise, at step 260, the device tests whether the variable V is equal to the quantity 2N−2. If equal, function FB should be applied, and processing proceeds to step 265 where the device increments C and updates KC by computing KC←FB(KC) by
At step 270, the device checks whether the value of V exceeds 2N−2. If not, processing proceeds directly to step 280. If V is larger than 2N−2, the value of V is diminished by 2N−2 and processing proceeds to step 280. At step 280, V and N are each decremented, then processing proceeds to step 230.
After performing a state update function at step 235, step 245, step 255, or step 265, the client process terminates successfully at step 290. After the successful conclusion of the process of
Note that each iteration of the process of
Server-Side Indexed Key Derivation
The server also obtains the client's base key value K0 (for example, by retrieving K0) from the server's memory, by cryptographically deriving K0 using other secret keys or secret algorithms, by obtaining K0, from a third party such as a key server, etc.). The server also knows or obtains D. At step 310, the server validates C to reject any possible invalid values of C. At step 320, the temporary variables N, V, and K are initialized with the values of D, C, and K0, respectively. At step 330, the server checks; whether the value of V is equal to zero. If so, the value of K equals the client's current secret (KC), and the process concludes at step 390. Otherwise, processing continues to step 340 where the server tests whether V equals the value 2N−2. If so, the value of K equals the client's current secret (KC), and the process concludes at step 390. Otherwise, processing continues to step 350 where the server tests whether V equals the value 2(2N−2). If so, the value of K equals the client's current secret (KC), and the process concludes at step 390. Otherwise, at step 360, the server checks whether V is larger than 2N−2. If not, processing continues at step 370 where V is decremented, K is updated by applying FA (i.e., K←FA(K)), and N is decremented. If the test at step 360 reveals that V is larger than 2N−2, processing continues to step 380, where the value 2N−1 is subtracted from V, K is updated by applying FB (i.e., K←FB(K)), and N is decremented. After either step 370 or step 380, processing continues at step 330. Processing continues until step 330, step 340, or step 350 indicates completion. When the process of
State Transformation Operations
The above discussion involved the exemplary cryptographic operations FA and FB, and their inverses FA−1 and FB−1, which will now be described in greater detail. A variety of such functions can be used, and the most appropriate form for these functions depends on the requirements and characteristics of the system.
In the exemplary functions shown in
The structure of the function FB can be essentially identical, except that different keys are used. In particular, the first DES operation 455 encrypts the right half of input 450 using key KB1, and DES operation 460 encrypts the XOR of the left half and the first DES result using key KB2. As with FA, the result left half 465 and right half 468 are combined to produce the final result 470.
The function FA−1 (the inverse of FA) is computed using similar functions as FA but in the opposite order. The input 475 is divided into a left half 476 and right half 477. At DES operation 478, the left half 476 is encrypted using the DES key KA2, and the result is XORed with the right half 477. The XOR result becomes the result right half 481 and is used as the input to DES operation 479 which encrypts using the key KA1. The result of the second DES operation 479 is XORed with the input left half 476 to produce the result left half 480. Finally, the result left half 480 and right half 481 are combined to produce the final result 482. The function FB−1 is similar to FA−1 except that the input 485 is transformed into output 490 using keys KB2 and KB1 instead of KA2 and KA1.
The primary objective of the functions FA, FB, FA−1, and FB−1 is to destroy the usefulness of partial information about the input that might have been obtained by an attacker. For example, the DES operations used in the exemplary function FA shown in
Thus partial statistical information about individual DES input bits does not provide useful statistical information about the DES output bits, provided that attackers never gain enough information to be able to guess the transformation operation entire input.
Other types of functions can be used for FA and FB. For example, if the input state is an odd value between 0 and 2B, FA and FB could be implemented using multiplication modulo 2B with odd constants and the inverse functions could be implemented using multiplication with the constants' inverses also mod 2B. (Of course, other operations such as multiplication with prime moduluses can also be used.) The foregoing are provided as examples only; one of ordinary skill in the art will appreciate that a wide variety of other functions exist that can be used to implement functions FA, FB, FA−1, and FB−1.
For additional leak resistance, larger states can be used, for example a 256-bit state can be implemented by using four 64-bit blocks and using four (or more) DES operations to update the state, or by using two (or more) applications of a 128-bit hash function.
In alternate embodiments, other key update processes can be used. For example, by using more than two update functions (and their inverses), each parent state can have more than 2 child states. In fact, parents can have any number of child states, although as the number of child states increases, the number of cryptographic operations involving the parent state value, and the number of states sharing the same secret key, also increase; thus potentially increasing attackers' opportunity to attack the system.
The type of state updating process illustratively described with respect to
In yet another alternate embodiment, the client can cache a value at each vertical level or row. By caching higher-up values, it is not necessary to perform inverse operations, but slightly more memory is required. In such an embodiment, an average of two applications of FA or FB (which, in such an embodiment, do not need to have easy inverse functions) are required per operation if only bottom-level (single-use) states are used for transactions. A diagram of the state update processes for such an implementation would resemble a hash tree. For implementations requiring constant-time or more predictable performance, the additional processing time available during operations requiring only a single application of FA or FB can be used to precompute values that will be needed in the future, and thereby limit the execution time to two FA or FB operations per transaction.
In still other embodiments, the key index used by the server can be a value other than a transaction counter, since all the server requires is information sufficient to derive the current transaction key from the root key.
In some applications, C can be incremented periodically (e.g., if C is driven by a timer) or by some event other than transactions being performed. In such embodiments, if the client (or server) fails to correctly update C and derive the corresponding updated key, the transaction will fail. If the first value of C that is tried by the client (or server) fails, other likely session key values (such as those with close values of C) can be tried. (Of course, if the client and server versions of C diverge too far, the transaction will not proceed.) While the key index (e.g., C) is normally exchanged explicitly, in cases such as this the server might be able to guess or obtain C indirectly.
If both the client and server need to be secured against external monitoring attacks, the transaction can be performed using the larger of the two parties' transaction counters C. In particular, the client and server can exchange counter values, and (if the counters are not equal) each device can set its counter value to equal the larger of its value and the received value. The device with the lower value updates its secret to derive the appropriate transaction key. This update can be implemented by applying a combination of the usual update functions and their inverses. (For example, referring to the technique exemplified in
Finally, the actual value used for the transaction key can be the value produced from the transformation function, or a value derived from the transformation result can be used. For example, the transformation result can be encrypted or hashed to produce the session key. A hashing step can help to limit the number of operations performed with any given key and thus help to limit the amount of information about the key that can leak to attackers. Alternatively or additionally, additional hashing operations can be performed periodically during the use of the session key, or fresh session keys can be required periodically.
To observe the largest possible number of transactions with a given secret key, an attacker might try to reset a target device before the device's memory can be updated with the new value of KC (e.g., during or immediately after the computation of FA or FB). However, such a reset does not necessarily mean an attack is in progress, since resets can occur during the normal operation of many systems. (For example, power can be lost if a smartcard is removed during a transaction.) Therefore, in a preferred embodiment, a failure counter stored in nonvolatile memory is updated prior to each update process. Before the update begins, the counter is tested to determine whether the number of sequential failures exceeds a maximum value and, if not, the transaction proceeds normally. Once the new value of KC has been computed and safely written to memory and C has been incremented, the failure counter is reset. The probability that the counter threshold will be exceeded during normal operation of the device (i.e., when no attack is in progress) will be small, particularly if the update process is rapid.
The exemplary key update process described with regard to
Other Considerations
Cryptographic operations should normally be checked to ensure that incorrect computations do not compromise keys or enable other attacks. Cryptographic implementations of the techniques disclosed herein can be combined with error-detection and/or error-correction logic to ensure that cryptographic operations are performed correctly. For example, a simple and effective technique is to perform cryptographic operations twice, ideally using two independent hardware processors and implementations, with a comparator to verify that both produce identical results. If the results produced by the two units do not match, the comparator will prevent either result from being used. In situations where security is more important than reliability, the comparator can make the device self-destruct if serious errors occur. For example, the comparator can cause a self-destruct if two defective DES operations occur sequentially or if five defective DES operations occur during the lifetime of the device. In some cryptosystems, redundancy is not necessary. For example, with RSA, self-checking functions can be incorporated into the cryptosystem implementation itself or verification can be performed after the operations.
Self-diagnostic functions such as a POST (power-on-self-test) should also be incorporated to verify that cryptographic functions have not been damaged. In some smartcards and other devices, the ATR (answer-to-reset) is provided before a comprehensive self-test can be completed. In such cases, the self-test can be deferred until the first transaction or until a sufficient idle period. For example, a flag indicating successful POST completion can be set upon initialization. While the card is waiting for a command from the host system, it can attempt the POST. Any I/O received during the POST will cause an interrupt, which will cancel the POST (leaving the POST-completed flag at zero). If any cryptographic function is called, the device will check the POST flag and (if it is not set) perform the POST first.
Conclusions
This patent encompasses a family of related techniques that enable the construction of devices that are significantly more resistant to attack than devices of similar cost and complexity that do not use the techniques disclosed herein. In addition, multiple security techniques might be required to make a system secure; and leak resistance can be used in conjunction with other security methods or countermeasures.
As those skilled in the art will appreciate, the techniques described above are not limited to particular host environments or form factors. Rather, they can be used in a wide variety of applications, including without limitation: cryptographic smartcards of all kinds including without limitation smartcards substantially compliant with ISO 7816-1, ISO 7816-2, and ISO 7816-3 (“ISO 7816-compliant smartcards”); contactless and proximity-based smartcards and cryptographic tokens; stored value cards and systems; cryptographically secured credit and debit cards; customer loyalty cards and systems; cryptographically authenticated credit cards; cryptographic accelerators; gambling and wagering systems; secure cryptographic chips; tamper-resistant microprocessors; software programs (including without limitation programs for use on personal computers, servers, etc. and programs that can be loaded onto or embedded within cryptographic devices); key management devices; banking key management systems; secure web servers; electronic payment systems; micropayment systems and meters; prepaid telephone cards; cryptographic identification cards and other identity verification systems; systems for electronic funds transfer; automatic teller machines; point of sale terminals; certificate issuance systems; electronic badges; door entry systems; physical locks of all kinds using cryptographic keys; systems for decrypting television signals (including, without limitation broadcast television, satellite television, and cable television); systems for decrypting enciphered music and other audio content (including music distributed over computer networks); systems for protecting video signals of all kinds; intellectual property protection and copy protection systems (such as those used to prevent unauthorized copying or use of movies, audio content, computer programs, video games, images, text, databases, etc.); cellular telephone scrambling and authentication systems (including telephone authentication smartcards); secure telephones (including key storage devices for such telephones); cryptographic PCMCIA cards; portable cryptographic tokens; and cryptographic data auditing systems.
All of the foregoing illustrates exemplary embodiments and applications from which related variations, enhancements and modifications will be apparent without departing from the spirit and scope of those particular techniques disclosed herein. Therefore, the invention(s) should not be limited to the foregoing disclosure, but rather construed by the claims appended hereto.
This application is a continuation of U.S. application Ser. No. 13/010,034, filed Jan. 20, 2011, which is a continuation of U.S. application Ser. No. 11/977,392, filed Oct. 24, 2007, which is a continuation of U.S. application Ser. No. 10/396,975, filed Mar. 24, 2003 now U.S. Pat. No. 7,941,666, which is a continuation of U.S. application Ser. No. 09/347,493, filed Jul. 2, 1999 now U.S. Pat. No. 6,539,092, issued as U.S. Pat. No. 6,539,092 on Mar. 25, 2003, which claims the benefit of U.S. Provisional Application No. 60/091,644, filed Jul. 2, 1998, each of which is incorporated in its entirety by this reference thereto.
Number | Name | Date | Kind |
---|---|---|---|
1657411 | Scherbius | Jan 1928 | A |
2632058 | Gray | Mar 1953 | A |
2733432 | Breckman | Jan 1956 | A |
3816762 | Holt, Jr. | Jun 1974 | A |
4078152 | Tuckerman, III | Mar 1978 | A |
4107458 | Constant | Aug 1978 | A |
4139839 | Engel et al. | Feb 1979 | A |
4157454 | Becker | Jun 1979 | A |
4200770 | Hellman et al. | Apr 1980 | A |
4202051 | Davida et al. | May 1980 | A |
4203166 | Ehrsam et al. | May 1980 | A |
4211919 | Ugon | Jul 1980 | A |
4214126 | Wipff | Jul 1980 | A |
4225962 | Meyr et al. | Sep 1980 | A |
4243890 | Miller et al. | Jan 1981 | A |
4268898 | Brown | May 1981 | A |
4295041 | Ugon | Oct 1981 | A |
4309569 | Merkle | Jan 1982 | A |
4369332 | Campbell, Jr. | Jan 1983 | A |
4405829 | Rivest et al. | Sep 1983 | A |
4563546 | Glitz | Jan 1986 | A |
4569052 | Cohn et al. | Feb 1986 | A |
4570084 | Griffin et al. | Feb 1986 | A |
4605820 | Campbell, Jr. | Aug 1986 | A |
4605921 | Riddle et al. | Aug 1986 | A |
4622480 | Uchimura et al. | Nov 1986 | A |
4661658 | Matyas | Apr 1987 | A |
4669117 | Van Eck | May 1987 | A |
4680688 | Inou et al. | Jul 1987 | A |
4686392 | Lo | Aug 1987 | A |
4759063 | Chaum | Jul 1988 | A |
4776011 | Busby | Oct 1988 | A |
4799258 | Davies | Jan 1989 | A |
4813024 | Lisimaque et al. | Mar 1989 | A |
4881264 | Merkle | Nov 1989 | A |
4888800 | Marshall et al. | Dec 1989 | A |
4888801 | Foster et al. | Dec 1989 | A |
4905176 | Schulz | Feb 1990 | A |
4908038 | Matsumura et al. | Mar 1990 | A |
4916333 | Kowalski | Apr 1990 | A |
4932053 | Fruhauf et al. | Jun 1990 | A |
4932057 | Kolbert | Jun 1990 | A |
4933969 | Marshall et al. | Jun 1990 | A |
4937649 | Shiba et al. | Jun 1990 | A |
4937866 | Crowther et al. | Jun 1990 | A |
4944007 | Austin | Jul 1990 | A |
4969188 | Schobi | Nov 1990 | A |
4972472 | Brown et al. | Nov 1990 | A |
5017766 | Tamada et al. | May 1991 | A |
5068894 | Hoppe | Nov 1991 | A |
5081677 | Green et al. | Jan 1992 | A |
5086467 | Malek | Feb 1992 | A |
5136643 | Fischer | Aug 1992 | A |
5136646 | Haber et al. | Aug 1992 | A |
5144667 | Pogue, Jr. et al. | Sep 1992 | A |
5149992 | Allstot et al. | Sep 1992 | A |
5157725 | Lindholm | Oct 1992 | A |
5159632 | Crandall | Oct 1992 | A |
5165098 | Hoivik | Nov 1992 | A |
5177430 | Mohel | Jan 1993 | A |
5181243 | Saltwick et al. | Jan 1993 | A |
5216713 | Lindholm | Jun 1993 | A |
5241598 | Raith | Aug 1993 | A |
5243648 | Gilardi et al. | Sep 1993 | A |
5249294 | Griffin, III et al. | Sep 1993 | A |
5293029 | Iijima | Mar 1994 | A |
5297201 | Dunlavy | Mar 1994 | A |
5297207 | Degele | Mar 1994 | A |
5311595 | Bjerrum et al. | May 1994 | A |
5341423 | Nossen | Aug 1994 | A |
5355413 | Ohno | Oct 1994 | A |
5369706 | Latka | Nov 1994 | A |
5399996 | Yates et al. | Mar 1995 | A |
5401950 | Yoshida | Mar 1995 | A |
5402402 | Kagami et al. | Mar 1995 | A |
5404402 | Sprunk | Apr 1995 | A |
5412379 | Waraksa et al. | May 1995 | A |
5412723 | Canetti et al. | May 1995 | A |
5412730 | Jones | May 1995 | A |
5414614 | Fette et al. | May 1995 | A |
5420925 | Michaels | May 1995 | A |
5428684 | Akiyama et al. | Jun 1995 | A |
5434919 | Chaum | Jul 1995 | A |
5444288 | Jacobs | Aug 1995 | A |
5450563 | Gregor | Sep 1995 | A |
5455862 | Hoskinson | Oct 1995 | A |
5477039 | Lisimaque et al. | Dec 1995 | A |
5481555 | Wade et al. | Jan 1996 | A |
5483182 | Rybicki | Jan 1996 | A |
5483598 | Kaufman et al. | Jan 1996 | A |
5495098 | Pailles et al. | Feb 1996 | A |
5506905 | Markowski et al. | Apr 1996 | A |
5511123 | Adams | Apr 1996 | A |
5514982 | Hall et al. | May 1996 | A |
5515438 | Bennett et al. | May 1996 | A |
5539825 | Akiyama et al. | Jul 1996 | A |
5539827 | Liu | Jul 1996 | A |
5544086 | Davis et al. | Aug 1996 | A |
5546463 | Caputo et al. | Aug 1996 | A |
5551013 | Beausoleil et al. | Aug 1996 | A |
5552776 | Wade et al. | Sep 1996 | A |
5557346 | Lipner et al. | Sep 1996 | A |
5559887 | Davis et al. | Sep 1996 | A |
5559890 | Obermeier et al. | Sep 1996 | A |
5572112 | Saeki et al. | Nov 1996 | A |
5600273 | Hall et al. | Feb 1997 | A |
5600324 | Reed et al. | Feb 1997 | A |
5602917 | Mueller | Feb 1997 | A |
5608614 | Ohnishi et al. | Mar 1997 | A |
5623548 | Akiyama et al. | Apr 1997 | A |
5625692 | Herzberg et al. | Apr 1997 | A |
5625695 | M'Raihi et al. | Apr 1997 | A |
5631492 | Ramus et al. | May 1997 | A |
5633930 | Davis et al. | May 1997 | A |
5636157 | Hesson et al. | Jun 1997 | A |
5638444 | Chou et al. | Jun 1997 | A |
5663896 | Aucsmith | Sep 1997 | A |
5664017 | Gressel et al. | Sep 1997 | A |
5668877 | Aziz | Sep 1997 | A |
5670934 | Ina et al. | Sep 1997 | A |
5675649 | Brennan et al. | Oct 1997 | A |
5696827 | Brands | Dec 1997 | A |
5703413 | Treharne | Dec 1997 | A |
5708711 | Rosauer et al. | Jan 1998 | A |
5710834 | Rhoads | Jan 1998 | A |
5721777 | Blaze | Feb 1998 | A |
5727062 | Ritter | Mar 1998 | A |
5727063 | Aiello et al. | Mar 1998 | A |
5733047 | Furuta et al. | Mar 1998 | A |
5737419 | Ganesan | Apr 1998 | A |
5745577 | Leech | Apr 1998 | A |
5757907 | Cooper et al. | May 1998 | A |
5761306 | Lewis | Jun 1998 | A |
5764766 | Spratte | Jun 1998 | A |
5778065 | Hauser et al. | Jul 1998 | A |
5778069 | Thomlinson et al. | Jul 1998 | A |
5778074 | Garcken et al. | Jul 1998 | A |
5781631 | Chaum | Jul 1998 | A |
5784464 | Akiyama et al. | Jul 1998 | A |
5796830 | Johnson et al. | Aug 1998 | A |
5796836 | Markham | Aug 1998 | A |
5796839 | Ishiguro | Aug 1998 | A |
5812669 | Jenkins et al. | Sep 1998 | A |
5821775 | Mehta et al. | Oct 1998 | A |
5825881 | Colvin, Sr. | Oct 1998 | A |
5835599 | Buer | Nov 1998 | A |
5838795 | Mittenthal | Nov 1998 | A |
5848159 | Collins et al. | Dec 1998 | A |
5859548 | Kong | Jan 1999 | A |
5870478 | Kawamura | Feb 1999 | A |
5892829 | Aiello et al. | Apr 1999 | A |
5905399 | Bosnyak et al. | May 1999 | A |
5907832 | Pieterse et al. | May 1999 | A |
5914471 | Van De Pavert | Jun 1999 | A |
5915025 | Taguchi et al. | Jun 1999 | A |
5917168 | Nakamura et al. | Jun 1999 | A |
5917754 | Pathak et al. | Jun 1999 | A |
5917911 | Dabbish et al. | Jun 1999 | A |
5944833 | Ugon | Aug 1999 | A |
5946397 | M'Raihi et al. | Aug 1999 | A |
5982900 | Ebihara et al. | Nov 1999 | A |
5991415 | Shamir | Nov 1999 | A |
5994917 | Wuidart | Nov 1999 | A |
5995624 | Fielder et al. | Nov 1999 | A |
5995629 | Reiner | Nov 1999 | A |
5998978 | Connell et al. | Dec 1999 | A |
6009174 | Tatebayashi et al. | Dec 1999 | A |
6009177 | Sudia | Dec 1999 | A |
6018717 | Lee et al. | Jan 2000 | A |
6028454 | Elmasry et al. | Feb 2000 | A |
6031912 | Moulart et al. | Feb 2000 | A |
6041122 | Graunke et al. | Mar 2000 | A |
6041123 | Colvin, Sr. | Mar 2000 | A |
6041412 | Timson et al. | Mar 2000 | A |
6046608 | Theogarajan | Apr 2000 | A |
6047068 | Rhelimi et al. | Apr 2000 | A |
6049613 | Jakobsson | Apr 2000 | A |
6064724 | Kelly | May 2000 | A |
6064740 | Curiger et al. | May 2000 | A |
6066965 | Blomgren et al. | May 2000 | A |
6069497 | Blomgren et al. | May 2000 | A |
6069954 | Moreau | May 2000 | A |
6069957 | Richards | May 2000 | A |
6070795 | Feiken | Jun 2000 | A |
6075865 | Scheidt et al. | Jun 2000 | A |
6078663 | Yamamoto | Jun 2000 | A |
6090153 | Chen et al. | Jul 2000 | A |
6097811 | Micali | Aug 2000 | A |
6101477 | Hohle et al. | Aug 2000 | A |
6107835 | Blomgren et al. | Aug 2000 | A |
6115601 | Ferreira | Sep 2000 | A |
6128391 | Denno et al. | Oct 2000 | A |
6181596 | Horne et al. | Jan 2001 | B1 |
6185307 | Johnson, Jr. | Feb 2001 | B1 |
6185596 | Hadad et al. | Feb 2001 | B1 |
6185685 | Morgan et al. | Feb 2001 | B1 |
6211456 | Seningen et al. | Apr 2001 | B1 |
6222923 | Schwenk | Apr 2001 | B1 |
6226750 | Trieger | May 2001 | B1 |
6236981 | Hill | May 2001 | B1 |
6247129 | Keathley et al. | Jun 2001 | B1 |
6278783 | Kocher et al. | Aug 2001 | B1 |
6289455 | Kocher et al. | Sep 2001 | B1 |
6298442 | Kocher et al. | Oct 2001 | B1 |
6304658 | Kocher et al. | Oct 2001 | B1 |
6327661 | Kocher et al. | Dec 2001 | B1 |
6336188 | Blake-Wilson et al. | Jan 2002 | B2 |
6345359 | Bianco | Feb 2002 | B1 |
6373948 | Wool | Apr 2002 | B1 |
6381699 | Kocher et al. | Apr 2002 | B2 |
6393567 | Colnot | May 2002 | B1 |
6434238 | Chaum et al. | Aug 2002 | B1 |
6442525 | Silverbrook et al. | Aug 2002 | B1 |
6448981 | Kaczmarski | Sep 2002 | B1 |
6453296 | Iwamura | Sep 2002 | B1 |
6510518 | Jaffe et al. | Jan 2003 | B1 |
6539092 | Kocher | Mar 2003 | B1 |
6577734 | Etzel et al. | Jun 2003 | B1 |
6654884 | Jaffe et al. | Nov 2003 | B2 |
6690795 | Richards | Feb 2004 | B1 |
6698662 | Feyt et al. | Mar 2004 | B1 |
6735313 | Bleichenbacher et al. | May 2004 | B1 |
6748410 | Gressel et al. | Jun 2004 | B1 |
6978370 | Kocher | Dec 2005 | B1 |
7073072 | Salle | Jul 2006 | B1 |
7599488 | Kocher et al. | Oct 2009 | B2 |
7941666 | Kocher | May 2011 | B2 |
20010010723 | Pinkas | Aug 2001 | A1 |
20010016908 | Blake-Wilson et al. | Aug 2001 | A1 |
20010053220 | Kocher et al. | Dec 2001 | A1 |
20020118190 | Greasley | Aug 2002 | A1 |
20020124178 | Kocher et al. | Sep 2002 | A1 |
20030028771 | Kocher et al. | Feb 2003 | A1 |
20030188158 | Kocher | Oct 2003 | A1 |
20060045264 | Kocher et al. | Mar 2006 | A1 |
20080022146 | Kocher et al. | Jan 2008 | A1 |
20080059826 | Kocher et al. | Mar 2008 | A1 |
Number | Date | Country |
---|---|---|
19511298 | Oct 1996 | DE |
0240328 | Oct 1987 | EP |
0304733 | Mar 1989 | EP |
0424415 | May 1991 | EP |
0452031 | Oct 1991 | EP |
0529261 | Mar 1993 | EP |
0563912 | Oct 1993 | EP |
0582395 | Feb 1994 | EP |
0656708 | Jun 1995 | EP |
0660562 | Jun 1995 | EP |
0790547 | Aug 1997 | EP |
0826169 | Nov 2002 | EP |
1080400 | Nov 2002 | EP |
1064752 | Aug 2003 | EP |
1062633 | Dec 2003 | EP |
1204948 | Feb 2004 | EP |
1084543 | Jan 2008 | EP |
2738970 | Mar 1997 | FR |
2738971 | Mar 1997 | FR |
60-146361 | Aug 1985 | JP |
62-082702 | Apr 1987 | JP |
62-166489 | Jul 1987 | JP |
62-260406 | Nov 1987 | JP |
64-081087 | Mar 1989 | JP |
02-187888 | Jul 1990 | JP |
05-094458 | Apr 1993 | JP |
09-163469 | Jun 1997 | JP |
10-084223 | Mar 1998 | JP |
10-171717 | Jun 1998 | JP |
10-197610 | Jul 1998 | JP |
WO 97-13342 | Apr 1967 | WO |
WO 97-14085 | Apr 1997 | WO |
WO 97-14086 | Apr 1997 | WO |
WO 97-33217 | Sep 1997 | WO |
WO 98-52319 | Nov 1998 | WO |
WO 99-08411 | Feb 1999 | WO |
WO 99-49416 | Sep 1999 | WO |
WO 99-63419 | Dec 1999 | WO |
WO 99-63696 | Dec 1999 | WO |
Entry |
---|
Kocher, Paul, U.S. Appl. No. 13/010,034, filed Jan. 20, 2011, Office Action dated Dec. 13, 2011 re Restriction Requirement, 8 pages. |
Kocher, Paul, U.S. Appl. No. 13/010,034, filed Jan. 20, 2011, Response dated Feb. 1, 2012 to the Office Action dated Dec. 13, 2011 re Restriction Requirement, 3 pages. |
Leighton, Tom, et al., “Secret-Key Agreement without Public-Key Cryptography (Extended Abstract),” Advances in Cryptology, CRYPTO '93, LNCS 773, p. 456-479, 1994, Springer-Verlag Berlin Heidelberg 1994. 24 pages. |
Lee, Jooyoung, et al., “Tree-based Key Distribution Patterns,” Lecture Notes in Computer Science, 2006, vol. 3897/2006, 189-204, DOI: 10.1007/11693383—13. 14 pages. |
Draper, et al., “Circuit Techniques in a 266-MHz MMX-Enabled Processor,” IEEE Journal of Solid-State Circuits, vol. 32, No. 11, pp. 1650-1664, Nov. 1997, 15 pages. |
Notification Concerning Transmittal of International Preliminary Report on Patentability (Chapter I) dated Dec. 10, 2009, including Written Opinion of the Int'l Searching Authority re International Application No. PCT/US2008/003961, 8 pages. |
Kocher, Paul, “Timing Attacks on Implementations of Diffie-Hellman, RSA, DSS and Other Systems,” in: Koblitz, N., Advances in Cryptology—CRYPTO '96 (Berlin, Springer, 1996), Aug. 18, 1996, XP000626590, 10 pages. |
“Security Requirements for Cryptographic Modules,” Federal Information Processing Standards Publication (FIPS PUB) 140-1, U.S. Department of Commerce, National Institute of Commerce, National Institute of Standards and Technology, Jan. 1994, 49 pages. |
Ryan, John, “Blinds for Thermodynamic Cipher Attacks,” unpublished material on the world wide web at http://www.cypertrace.com/papers/thrmatak.html, Mar. 1996. 8 pages. |
“Data Encryption Standard,” Federal Information Processing Standards Publication (FIPS PUB) 46-2, U.S. Department of Commerce, National Institute of Standards and Technology, Dec. 30, 1993, 19 pages. |
Biham, E., et al., “Differential Fault Analysis of Secret Key Cryptosystems,” in Kaliski, B., Advances in Cryptology—CRYPTO 97, (Berlin, Springer, 1997) 17th Annual International Cryptology Conference, Aug. 17-21, 1997, pp. 513-525, 14 pages. |
Wayner, Peter, “Code Breaker Cracks Smart Cards' Digital Safe,” The New York Times on the web, Jun. 22, 1998, http://www.nytimes.com/library/tech/98/06/biztech/articles/22card.html—3 pages. |
Krawczyk, H., et al., “HMAC: Keyed-Hashing for Message Authentication,” Network Working Group Request for Comments RFC 2104, Feb. 1997, 11 pages. |
Based on “Karn/Hoey/Outerbridge implementations (Khodes): File DESC.C from RSAREF-Data Encryption Standard routines for RSAREF,” Jul. 27, 2010, 12 pages. |
Schneier, Bruce, “Applied Cryptography, Second Edition: Protocols, Algorithms, and Source Code in C,” Oct. 18, 1995, 1027 online pages. |
Menezes, A. J. et al., Handbook of Applied Cryptography (CRC Press, 1996), pp. 285-298, 312-319, 452-462, 475, and 515-524 found at http://www.cacr.math.uwaterloo.ca/hac/—on Jun. 22, 2011, 45 pages. |
Hachez, et al., “Timing Attack: What Can Be Achieved by a Powerful Adversary?” May 1999, 8 pages. |
Kocher, Paul C., “Cryptanalysis of Diffie-Hellman, RSA, DSS, and Other Systems Using Timing Attacks,” Report on Dec. 7, 1995, 6 pages. |
Bauer, Friedrich L., “Cryptology—Methods and Maxims”, Technical University Munich, 1998, pp. 31-48, 18 pages. |
Jueneman, Robert R., “Analysis of Certain Aspects of Output Feedback Mode,” Satellite Business Systems, 1998, pp. 99-127, 30 pages. |
Conner, Doug (technical editor), “Cryptographic Techniques—Secure your Wireless Designs”, Jan. 18, 1996, pp. 57-68, 11 pages. |
Kaliski, Burt, “Timing Attacks on Cryptosystems,” RSA Laboratories, Bulletin No. 2, Jan. 23, 1996, 2 pages. |
Bellare, et al., “Incremental Cryptography: The Case of Hashing and Signing” in: Desmedt, Y., Advances in Cryptology-Crypto '94 Proceedings (Berlin, Springer, 1994) pp. 216-233, 18 pages. |
Hornauer, et al., “Markov Ciphers and Alternating Groups”, Eurocrypt '91, 1991; pp. 453-460, 8 pages. |
Koblitz, Neal, “A Course in Number Theory and Cryptography,” Second Edition, May 1994, Chapter III, pp. 54-77, 13 pages. |
Lai, et al., “Markov Ciphers and Differential Cryptanalysis”, Springer-Verlag, 1998; pp. 17-38, 22 pages. |
Back, Adam, “Non-Interactive Forward Secrecy,” Sep. 6, 1996, found at http://www.cypherspace.org/adam/nifs/stmt.txt, Jul. 12, 2011, 2 pages. |
Bell, Jim, “Spread-Spectrum Computer Clock”? Dec. 24, 1995, Google Beta Groups, last modified Aug. 22, 1999, found at http://lambda-diode.com/resources/tempest/jb.html Jul. 12, 2011, 3 pages. |
Bellare, et al., “Optimal Asymmetric Encryption,” Advanced Networking Laboratories, Springer-Verlag, USA, 1998, pp. 92-111, 20 pages. |
Bellare, et al., “The Exact Security of Digital Signatures—How to Sign with RSA and Rabin,” Mar. 14, 1996, Advances in Cryptology—Eurocrypt '96 Proceedings, Lecture Notes in Computer Science, vol. 1070, U. Maurer ed., Springer-Verlag, pp. 1-17, 17 pages. |
Bellare et al., “Forward Integrity for Secure Audit Logs”, Nov. 23, 1997, USA, pp. 1-16, 16 pages. |
Frankel et al., “Optimal-Resilience Proactive Public-Key Cryptosystems,” IEEE Symposium on Foundations of Computer Science, 1997, 12 pages. |
Herzberg et al., “Proactive Public Key and Signature Systems”, Dec. 9, 1996, ACM Conference on Computer and Communications Security, 15 pages. |
Menezes, et al., “Pseudorandom Bits and Sequences,” Handbook of Applied Cryptography, CRC Press, Chapter 5, 1996, pp. 169-190, 22 pages. |
Menezes, et al., “Efficient Implementation,” Handbook of Applied Cryptography, CRC Press, Chapter 14, 1996, pp. 591-634, 44 pages. |
Anderson et al., “Tamper Resistance—a Cautionary Note”, The Second USENIX Workshop on Electronic Commerce Proceedings, Nov. 18-21, 1996, Oakland, CA, 11 pages. |
Guillou, L.C. et al., “Smart Cards and Conditional Access,” Advances in Cryptology—Eurocrypt '84; LNCS 209, Springer-Verlag, Berlin, Germany; (1985) Copyright (c) 1998, pp. 480-489, 10 pages. |
Guthery, Scott, “Smart Cards,” last changed May 28, 1998, found online at http://www.usenix.org/publications/login/1998-5/guthery.html Jul. 12, 2011, 6 pages. |
Kuhn, et al., “Soft Tempest: Hidden Data Transmission Using Electromagnetic Emanations,” Second Workshop on Information Hiding, Portland, Oregon, Apr. 15-17, 1998, 21 pages. |
Menezes, A. J. et al., “Handbook of Applied Cryptography,” Chapters 1, 5, and 7; CRC Press, 1997, Boca Raton, Florida, 130 pages. |
Beker et al., “Key Management for Secure Electronic Funds Transfer in a Retail Environment,” Proc. Crypto '84, Springer-Verlag, 1998, pp. 401-410, 10 pages. |
Daemen, Joan, “Management of Secret Keys: Dynamic Key Handling,” LNCS 1528, Proc. COSIC '97 Course, Springer-Verlag, 1998, pp. 264-276, 13 pages. |
Menezes, et al., “Handbook of Applied Cryptograph,”, CRC Press, Boca Raton, Florida (1997), pp. 71, 586, 636-637, 6 pages. |
ISO (International Organization for Standardization),“Banking—Key management (retail)—Part2: Key management techniques for symmetric ciphers,” ISO 11568-2 First edition Dec. 1, 1994, www.saiglobal.com/shop pp. 1-16, 16 pages. |
ISO (International Organization f or Standardization), “Banking—Key management (retail)—Part 3: Key life cycle for symmetric ciphers,” ISO 11568-3 First edition Dec. 1, 1994, www.saiglobal.com/shop pp. 1-16,. 16 pages. |
Daemen, Joan, “Management of Secret Keys: Dynamic Key Handling,” Course on Computer Security and Industrial Cryptography (COSIC '97—Jun. 1997). Presentation slides and declaration of Professor Bart Preneel dated Jun. 15, 2007, 10 pages. |
Davies, et al., “Security for Computer Networks: An Introduction to Data Security in Teleprocessing and Electronic Funds Transfer,” 2nd Ed., John Wiley & Sons, New York, NY, 1989. pp. 318-321, 6 pages. |
Bradley, Steven, “Derived Unique Key Per Transaction Schemes,” Some Applications of Mathematics to the Theory of Communications: Chapter 4, Ph.D. Thesis, University of London, England, 1994, pp. 132-199, 38 pages. |
Interbank Card Association, “PIN Manual: A Guide to the Use of Personal Identification Numbers in Interchange”, 1979, pp. 61-127, 69 pages. |
Sedgewick, Robert, “Algorithms,” 2nd Ed., Chapters 4 and 11, Addison-Wesley, Arlington, VA, 1988, 23 pages. |
RSA Data Security, “RSAREF Cryptographic Toolkit Source Code,” File R-RANDOM C, available from ftp://ftp.rsa.com last revised Apr. 15, 1994, created 1991, 8 pages. |
Rivest, Ronald, “Announce: Timing Cryptanalysis of RSA, DH, DDS,” Google Beta Groups, Dec. 11, 1995, 1 page. |
Lacy, et al., “CryptoLib Version 1.1,” File Bigpow.c from CryptoLib, United States, Nov. 1999, 13 pages. |
Frankel, et al., “Proactive RSA,” Lecture notes in Computer Science, 1996, 22 pages. |
Anderson, et al., “Robustness Principles for Public Key Protocols,” LNCS 963, Proc. Crypto '95, Aug. 27-31, 1995, pp. 236-247, 12 pages. |
Anderson, Ross, “Two Remarks on Public Key Cryptology”, Computer Laboratory, University of Cambridge, Technical Report, No. 549, Dec. 2002, ISSN 1476-2986, 7 pages. |
Boneh, et al., “On the Importance of Eliminating Errors in Cryptographic Computations,” Journal of Cryptology, 2001, vol. 14, No. 2, pp. 101-119, 17 pages. |
Burmester, et al., “A Secure and Efficient Conference Key Distribution System,” LNCS 1189, Proc. International Workshop on Security Protocols, 1996, Springer-Verlag, 1998, pp. 275-286, 11 pages. |
Gennaro, et al., “Robust Threshold DSS Signatures,” LNCS 1070, Proc. Eurocrypt '96, Springer-Verlag, 1998. pp. 354-371, 17 pages. |
Gillogly, et al., “Notes on Crypto '95 Invited Talks by R. Morris and A. Shamir,” Cipher 9, Sep. 18, 1995; http://www.ieee-security.org/Cipher/ConfReports/conf-rep-Crypto95.html—2 pages. |
Herzberg, et al., “Proactive Secret Sharing Or: How to Cope with Perpetual Leakage,” LNCS 963. Proc. Crypto '95, Springer-Verlag, 1998, pp. 339-352, 14 pages. |
Jablon, David P., “Strong Password-Only Authenticated Key Exchange”, Computer Communication Review, Sep. 25, 1996, vol. 26, No. 5, pp. 5-26, 22 pages. |
Kocher, P., Message: “Re: Timing cryptanalysis of RSA, DH, DSS (Tomazic, Risks-17.59),” The Risks Digest, Forum on Risks to the Public in Computers and Related Systems, vol. 17; Issue 60, Jan. 3, 1996, website: http://catless.ncl.ac.uk/Risks/17.60.html—1 page. |
Matsumoto, et al., “Speeding Up Secret Computations with Insecure Auxiliary Devices”, LNCS 403, Proc. Crypto '88, Springer-Verlag, 1998, pp. 497-506, 20 pages. |
Naccache, et al., “Can D.S.A. be Improved?”—Complexity Trade-Offs with the Digital Signature Standard-, LNCS 950, Proc. Eurocrypt '94, 1995, Springer-Verlag, 1998, pp. 77-85. 13 pages. |
Naccache, David, “Can O.S.S. be Repaired”?—Proposal for a New Practical Signature Scheme-, LNCS 765, Proc. Eurocrypt '93, 1994, Springer-Vertag, 1998, pp. 233-239, 8 pages. |
Quisquater, et al., “Fast Decipherment Algorithm for RSA Public-Key Cryptosystem,” Aug. 27, 1982, Electronics Letters Oct. 14, 1982, vol. 18, No. 21, pp. 905-907, 3 pages. |
Robshaw, et al., “Overview of Elliptic Curve Cryptosystems,” RSA Laboratories Technical Note, revised Jun. 27, 1997, website: http://www.rsa.com/rsalabs/node.asp?id=2013#—9 pages. |
Schnorr, C. P., “Efficient Signature Generation by Smart Cards,” Journal of Cryptology, 1991, pp. 161-174, 14 pages. |
Steiner, et al., “Diffie-Hellman Key Distribution Extended to Group Communication,” Third ACM Conf. Computer and Comm. Security, Mar. 1996, pp. 31-37, 7 pages. |
Yen et al., “RSA Speedup with Chinese Remainder Theorem Immune Against Hardware Fault Cryptanalysis”, IEEE Transactions on Computers, Apr. 2003, vol. 52, No. 4, pp. 461-472, 12 pages. |
Guillou, et al., “Smart Card, A Highly Reliable and Portable Security Device,” Advances in Cryptology—CRYPTO '86; LNCS 263, Springer-Verlag, Berlin, Germany; (1987) pp. 464-479, 16 pages. |
Highland, Harold Joseph, “The Tempest Over Leaking Computers,” Hardcopy Abacus, vol. 5, No. 2, Winter 1988, pp. 10-18, 53; http://cryptome.org/tempest-leak.htm—9 pages. |
Smulders, Peter, “The Threat of Information Theft by Reception of Electromagnetic Radiation from RS-232 Cables,” Computers and Security, vol. 9, pp. 53-58, 1990; Elsevier Science Publishers Ltd., 6 pages. |
Hevia, et al., “Strength of Two Data Encryption Standard Implementations Under Timing Attacks”, Lecture Notes in Computer Science 1380—Latin '98: Theoretical Informatics 3rd Latin American Symposium, Campinas, Brazil, Apr. 1998; pp. 192-205, 14 pages. |
Kocher, Paul, “Differential Power Analysis,” The Risks Digest, vol. 19(80), ACM Committee on Computers and Public Policy, New York, Jun. 10, 1998; http://catless.ncl.ac.uk/Risks/19.80.html#subj3—3 pages. |
Alon, et al., “Efficient Dynamic-Resharing ‘Verifiable Secret Sharing’ Against Mobile Adversary”, Mar. 25, 1995, 14 pages. |
Charnes, et al., “Comments on Soviet Encryption Algorithm,” Proc. EUROCRYPT '94, Springer-Verlag, 1998, pp. 433-438, 6 pages. |
Maurer, Ueli M., “A Provably-Secure Strongly-Randomized Cipher,” Springer-Verlag, 1998, 13 pages. |
Shamir, Adi, “How to Share a Secret,” Communications of the ACM, Nov. 1979, vol. 22, No. 11, pp. 612-613, 2 pages. |
De Rooij, Peter, “Efficient Exponentiation Using Precomputation and Vector Addition Chains,” 1994, Springer-Verlag, 1998, possibly a reprint from Advances in Cryptology, EUROCRYPT '94, pp. 389-399, 11 pages. |
Dimitrov, et al., “An Algorithm for Modular Exponentiation,” Information Processing Letters, vol. 66, Issue 3, pp. 155-159, May 15, 1998. 12 pages. |
Dimitrov, et al., “Two Algorithms for Modular Exponentiation Using Nonstandard Arithmetics,” IEICE Trans. Fundamentals, vol. E78-A, No. 1, Jan. 1995, 6 pages. |
Hong, et al., “New Modular Multiplication Algorithms for Fast Modular Exponentiation,” Springer-Verlag, 1998, from Advances in Cryptology, EUROCRYPT '96, 1996, pp. 166-177, 12 pages. |
Jedwab, et al., “Minimum weight modified signed-digit representations and fast exponentiation,” Jun. 26, 1989, Electronics Letters, vol. 25, No. 17, Aug. 17, 1989, pp. 1171-1172, 2 pages. |
Koc, Cetin K., “High-Radix and Bit Recoding Techniques for Modular Exponentiation,” Nov. 22, 1990, Intern. J. Computer Math, vol. 40, Gordon and Breach Science Publishers, S.A. (UK), pp. 139-156, 1991, 18 pages. |
Egecioglu, et al., “Exponentiation Using Canonical Recoding,” Theoretical Computer Science 129, Elsevier, 1994, pp. 407-417, 11 pages. |
Koc, Cetin K., “High-Speed RSA Implementation,” RSA Laboratories, Nov. 1994, 73 pages. |
Lim et al., “More Flexible Exponentiation with Precomputation”, Advances in Cryptology, Springer-Verlag, 1998, possible from CRYPTO '94, Aug. 1994, 13 pages. |
Anderson, et al., “Tiger: A Fast New Hash Function,” Fast Software Encryption, Third International Workshop Proceedings, Springer-Verlag, Berlin, Germany, 1996, pp. 89-97, 12 pages. |
Eberle, et al., “A 1 GBit/second GaAs DES Chip,” Proceedings of the 1992 IEEE Custom Integrated Circuits Conference, May 3-6, 1992, 4 pages. |
Eichelberger, et al., “Differential Current Switch—High Performance at Low Power”, IBM J. Res. Develop., 35(3):313-320, May 1991, 8 pages. |
Gonzalez, et al., “TCMOS: A Low Noise Power Supply Technique for Digital ICs,” Electronics Letters, 31(16):1338-1339, Aug. 3, 1995, 2 pages. |
Greub, et al., “High-Performance Standard Cell Library and Modeling Technique for Differential Advanced Bipolar Current Tree Logic”, IEEE Journal of Solid-State Circuits, 26(5):749-762, May 1991, 14 pages. |
Hough, et al., “New Approaches for On-Chip Power Switching Noise Reduction,” Proceedings of the IEEE1995 Custom Integrated Circuits Conference, May 1-4, 1995, pp. 133-136, 4 pages. |
Ivey, et al., “A Single Chip Public Key Encryption Sub-System,” IEEE J. Solid-State Circuits 24(4):1071-1075, Aug. 1989, 4 pages. |
Jarecki, Stanislaw, “Proactive Secret Sharing and Public Key Cryptosystems”, thesis, Massachusetts Institute of Technology, Sep. 1995, Cambridge, MA, 81 pages. |
Karlsson, et al., “Implementation of Bit-Serial Adders Using Robust Differential Logic”, Proc. IEEE Nordic Event in ASIC Design Conf., NORCHIP'97, Tallin, Estonia, Nov. 10-11, 1997, 8 pages. |
Lin, Mao-Chao, “Constant Weight Codes for Correcting Symmetric Errors and Detecting Unidirectional Errors,” IEEE Transactions on Computers, 42(11):1294-1302, Nov. 1993, 9 pages. |
Maier, et al., “A 533-MHz BiCMOS Superscalar RISC Microprocessor”, IEEE Journal of Solid-State Circuits, 32(11):1625-1634, Nov. 1997, 10 pages. |
Daemen et al., “The Block Cipher SQUARE,” Fast Software Encryption '97, Lecture Notes in Computer Science 1267, Springer-Verlag, Berlin Heidelberg, Germany, 1997, pp. 149-165,19 pages. |
Brassard, Gilles, “On Computationally Secure Authentication Tags Requiring Short Secret Shared Keys,” 1998, Springer-Verlag, pp. 79-86. 8 pages. |
Tabor, Jeff F., “Noise Reduction Using Low Weight and Constant Weight Coding Techniques”, Technical Report 1232, MIT Artificial Intelligence Laboratory, Dissertation, Massachusetts Institute of Technology, May 11, 1990, Cambridge, MA, 84 pages. |
Takashima et al., “Noise Suppression Scheme for Gigabit-Scale and Gigabyte/s Data-Rate LSI's,” IEEE Journal of Solid-State Circuits, vol. 33, No. 2, pp. 260-267, Feb. 1998, 8 pages. |
Naccache, et al., “Cryptographic Smart Cards,” IEEE Micro, vol. 16, No. 3, pp. 14-24, Jun. 1996,14 pages. |
Nordman et al., “User Guide to Power Management for PCs and Monitors”, Environmental Energy Technologies Division, Lawrence Berkeley National Laboratory, University of California, pp. 5, 9-14, Jan. 1997, Berkeley, CA, 8 pages. |
Maier, Cliff, “High Speed Microprocessor Cache Memory Hierarchies for Yield-Limited Technologies” dissertation, Rensselaer Polytechnic Institute, Troy, New York, Aug. 1996, 212 pages. |
Makie-Fukuda, et al., “Substrate Noise Reduction Using Active Guard Band Filters in Mixed-Signal Integrated Circuits”, 1995 Symposium on VLSI Circuits, Digest of Technical Papers, 33-34, Jun. 8-10, 1995, 2 pages. |
Maleki, et al., “Enhancement Source-Coupled Logic for Mixed-Mode VLSI Circuits”, IEEE Transactions on Circuits and Systems-II: Analog and Digital Signal Processing, 39(6), Jun. 1992, pp. 399-402, 4 pages. |
Oklobdzija, Vojin G., “Differential and Pass-Transistor CMOS Logic for High-Performance Systems”, Proc. 21st International Conference on Microelectronics (MIEL '97), vol. 2, Nis, Yugoslavia, Sep. 14-17, 1997, pp. 803-810, 8 pages. |
Schettler, et al., “A CMOS Mainframe Processor with 0.5-um Channel Length”, IEEE Journal of Solid-State Circuits, 25(5), Oct. 1990, pp. 1166-1177, 12 pages. |
Beker, et al., “Simplifying Key Management in Electronic Fund Transfer Point of Sale Systems,” Electronics Letters, 19(12):442-444, Jun. 9, 1983, 3 pages. |
Tallini, et al., “Design of Balanced and Constant Weight Codes for VLSI Systems”, IEEE Transactions on Computers, vol. 47, No. 5, May 1998, pp. 556-572, 17 pages. |
Texas Instruments Data Sheet, “SN54LS138, SN54S138, SN74LS138, SN74S138A: 3-Line to 8-Line Decoders/Demultiplexers”, Texas Instruments, Dallas, Texas, Revised Mar. 1998, 5 pages. |
Wang, et al., “On-Chip Decoupling Capacitor Design to Reduce Switching-Noise-Induced Instability in CMOS/SOI VLSI”, Proceedings 1995 IEEE International SOI Conference, pp. 100-101, Oct. 1995, 2 pages. |
Williams, et al., “Bipolar Circuit Elements Providing Self-Completion-Indication”, IEEE Journal of Solid-State Circuits, 25(1):309-312, Feb. 1990, 4 pages. |
Intel & Microsoft Corporations, “Advanced Power Management (APM); BIOS Interface Specification,” Rev. 1.2, Feb. 1996, USA. pp. 4, 5, and 8, 3 pages. |
Notice of Allowance in related U.S. Appl. No. 11/643,349, dated Sep. 28, 2009. |
Notice of Allowance in related U.S. Appl. No. 09/930,836, dated Nov. 5, 2009. |
EP Opposition for EP Application No. 99949533.6, May 15, 2008-Dec. 16, 2009, 98 pages, retrieved from European Patent website—https://register.eponline.org/espacenet. |
EP Opposition for EP Application No. 99940799.2, Jan. 18-Dec. 18, 2008, pp. 1-315, retrieved from European Patent website—https://register.eponline.org/espacenet. |
EP Opposition for EP Application No. 99940799.2, Jan. 18-Dec. 18, 2008, pp. 316-630, retrieved from European Patent Office website—https://register.eponline.org/espacenet. |
EP Opposition for EP Application No. 98966880.1, Jan. 15, 2008-Nov. 17, 2009, pp. 1-476, retrieved from European Patent Office website—https://register.eponline.org/espacenet. |
EP Opposition for EP Application No. 98966880.1, Jan. 15, 2008-Nov. 17, 2009, pp. 477-953, retrieved from European Patent Office website—https://register.eponline.org/espacenet. |
EP Opposition for EP Application No. 98966880.1, Jan. 15, 2008-Nov. 17, 2009, pp. 954-1430, retrieved from European Patent Office website—https://register.eponline.org/espacenet. |
EP Opposition for EP Application No. 98966880.1, Jan. 15, 2008-Nov. 17, 2009, pp. 1431-1669, retrieved from European Patent Office website—https://register.eponline.org/espacenet. |
EP Opposition for EP Application No. 98966880.1, Jan. 15, 2008-Nov. 17, 2009, pp. 1670-1906, retrieved from European Patent Office website—https://register.eponline.org/espacenet. |
EP Opposition for EP Application No. 99937153.7, Oct. 20, 2008-Jan. 21, 2010, 190 pages, https://register.eponline.org/espacenet. |
Notice of Allowance in related U.S. Appl. No. 11/981,495, dated May 5, 2010. |
Notice of Allowance in related U.S. Appl. No. 11/252,898, dated Mar. 30, 2010. |
Communication from the European Patent Office regarding further examination for EP Application No. 08000796.6, dated Sep. 16, 2010, 4 pages. |
Extended European Search Report in related European Patent Application No. 07075144.1-1237, dated Oct. 4, 2007, 5 pages. |
Extended European Search Report in related European Patent Application No. 08000796.6-1525, dated Feb. 6, 2009, 6 pages. |
Decision rejecting the opposition against European Patent No. 1084543, dated Oct. 6, 2009. |
Decision to discontinue the opposition proceedings in European Patent No. 1088295, dated Aug. 26, 2009. |
Communication from European Patent Office regarding further examination of the opposition(s) for EP Patent Application No. 99937153.7-1525 (EP Patent No. 1084543) dated Jul. 22, 2009. |
Patentee's Observations on withdrawn NXP B.V. opposition in European Patent Application No. 99937153.7-1525 (1084543), filed Jun. 2, 2009. |
Perry, Thomas J., “Assignment of Rights”, between NXP and Thomas J. Perry with Exhibit A of communications including the participation of Thomas J. Perry, dated Feb. 3, 2007, Phoenix, AZ. |
Stewart, Bill, “Assignment of Rights”, between NXP and Bill Stewart with Exhibit A of communications including the participation of Bill Stewart, dated Dec. 12, 2006, Santa Clara, CA. |
Cryptography Research, Inc., Observations on Oppositions to EP Application No. 99949533.6, dated Feb. 18, 2009, London, UK. |
Cryptography Research, Inc., Observations on Oppositions filed to EP Application No. 1050133, dated Nov. 13, 2007. |
European Patent Office, Summons to attend oral proceedings pursuant to Rule 115(1) EPC regarding EP Application No. 1050133, including the EPO's preliminary opinion, dated Jun. 16, 2008. |
Cryptography Research, Inc., Oppositions to EP Application No. 1050133 of Cryptography Research, Inc., Submissions by the Proprietor in response to the Summons to attend Oral Proceedings dated Oct. 2, 2008. |
NXP B.V., letter withdrawing its opposition to EP Application No. 1050133, dated Nov. 4, 2008. |
Visa Europe Services, Inc. letter withdrawing its opposition to EP Application No. 1050133, dated Sep. 9, 2008. |
Infineon Technologies AG; letter withdrawing its opposition to EP Application No. 1050133, dated Aug. 14, 2008. |
Cryptography Research, Inc., letter from Aidan Robson to EPO regarding EP Application No. 1050133, dated Nov. 13, 2008. |
European Patent Office “Communication of a Notice of Opposition”, to European Patent No. 1084543 by NXP B.V., dated Oct. 31, 2008. |
Notice & Grounds of Opposition of VISA Europe Services, Inc. against EP Patent No. 1050133, vol. 1, dated Feb. 2, 2007. |
Notice of Opposition to European Patent of Infineon Technologies, AG, against EP Patent No. 1050133, dated Feb. 3, 2007 ( in German language). |
Notice of Opposition to European Patent of NXP B.V. against EP Patent No. 1050133, dated Feb. 5, 2007. |
Notice & Grounds of Opposition of VISA Europe Services, Inc. against EP Patent No. 1050133, vol. 2, dated Feb. 1, 2007. |
Letter from Infineon Technologies, AG to the European Patent Office calling for the revocation of EP Patent No. 1050133, dated Feb. 3, 2007 (in English language). |
Notice of Opposition to European Patent of NXP B.V. against EP Patent No. 1088295, dated May 15, 2008. |
Letter from NXP B.V. to the European Patent Office concerning the Oral Proceedings against European Patent No. 1050133, dated Oct. 2, 2008. |
Stewart, Bill, Declaration of Bill Stewart regarding his newsgroup posting on Dec. 13, 1995, signed in Mountain View, CA, Oct. 2, 2008. |
Stewart, Bill, et al., “Announce: Timing cryptanalysis of RSA, DH, DSS”, posting on Google Groups sci/crypt, Dec. 13, 1995, http://groups.google.de/group/sci.crypt/browse. |
Stewart, Bill, “Potential defense against timing attack on Diffie-Hellman”, postings on Cypherpunks, Dec. 12-13, 1995, http://diswww.mit.edu/menelaus/cpunks/45312. |
Schneier, Bruce, Applied Cryptography, Second Edition: Protocols, Algorithms, and Source Code in C, Chap. 16.3, John Wiley & Sons, Inc. New York, NY, pp. 379-381. |
Meyer, Carl H., et al., Cryptography—A New Dimension in Computer Data Security, John Wiley & Sons, New York, NY, 1982, pp. 100-105, 457-464, and 486. |
Kocher, Paul, “Protection Against DPA and Related Attacks”, Electronics World, Mar. 2008; United Kingdom pp. 32-36. |
Black, Coral Elizabeth, “Witness Statement of Coral Elizabeth Black”, Opposition: Cryptography Research, Inc.'s European Patent No. 1050133 B1, Jun. 26, 2008, setting the public divulgation date of a previously cited reference as Feb. 7, 1995, United Kingdom. |
Brief Communication from the European Patent Office dated Aug. 11, 2008, enclosing “Further Submission on the Second Opponent's Opposition” to EP Patent No. 1150133 B1, dated Aug. 1, 2008, London, England. |
Naccache, David, Declaration of Professor David Naccache, with regards to his attendance during Adi Shamir's talk entitled “How to Check Modular Exponentiation” at the rump session of Eurocrypt 1997, held May 13, 1997, Paris, France; date of reference: Dec. 6, 2006. |
Grounds of Opposition, European Patent No. 1092297, in the name of Cryptography Research, Inc. , Opposition by VISA Europe Services, Inc. Jan. 25, 2008. |
Posting on sci.crypt newsgroup, Kocher, Paul C. et al., “Announce: Timing cryptanalysis of RSA, DH, DSS” et al., messages 1-51 of 51, Dec. 11, 1995 through Dec. 24, 1995, http://groups,google.com/group/sci.crypt. |
Piper, F., Key Management (Part 3.5) ZERGO: Information Security Training Club, Hampshire, U.K., Jan. 1993, Foils 6-18 to 6-30. |
Piper, F., Declaration of Jan. 21, 2008, University of London, England. |
American National Standard for Financial Services, secretariat—American Bankers Association (ANS/ABA X9.24-200x), Key Management Using Triple DEA and PKI, revised by Terry Benson, American National Standards Institute, Sep. 12, 2000. |
Davies & Price, Security for Computer Networks: An Introduction to Data Security in Teleprocessing Electronic Funds Transfer, John Wiley & Sons, New York, NY, 2nd Ed. 1989, 377 pages (entire book). |
Defendant VISA International Service Association's Final Invalidity Contentions for U.S. Pat. No. 6,304,658 Pursuant to Patent L.R. 3-6(b), Feb. 8, 2008, Case No. C04-04143 JW(HRL), U.S. District Court, Northern District of California, San Jose Division. |
Defendant VISA International Service Association's Final Invalidity Contentions for U.S. Pat. No. 6,381,699 Pursuant to Patent L.R. 3-6(b), Feb. 8, 2008, Case No. C04-04143 JW(HRL), U.S. District Court, Northern District of California, San Jose Division. |
Defendant VISA International Service Association's Final Invalidity Contentions for U.S. Pat. No. 6,510,518 Pursuant to Patent L.R. 3-6(b), Feb. 8, 2008, Case No. C04-04143 JW(HRL), U.S. District Court, Northern District of California, San Jose Division. |
Defendant VISA International Service Association's Final Invalidity Contentions for U.S. Pat. No. 6,654,884 Pursuant to Patent L.R. 3-6(b), Feb. 8, 2008, Case No. C04-04143 JW(HRL), U.S. District Court, Northern District of California, San Jose Division. |
Larsson, Patrick, “di/dt Noise in CMOS Integrated Circuits”, Analog Integrated Circuits and Signal Processing, 14: 113-129, Kluwer Academic Publishers, Boston, MA, 1997. |
Loy, James R., “Managing Differential Signal Displacement”, thesis, Rensselaer Polytechnic Institute, Troy, New York, Aug. 1993. |
Schindler, Volker, “High Speed RSA Hardware Based on Low-Power Pipelined Logic”, Dissertation, Institut fur Angewandte informationsverarbeitung and Kommunikationstechnologie, Graz University of Technology, Graz, Austria, Jan. 1997. |
Schneier, Bruce, Applied Cryptography, Chapter 12, 2nd Ed., 1996, John Wiley & Sons, pp. 265-301. |
VISA International Service Association's Preliminary Invalidity Contentions, filed in Case C04-4143JW in U.S. District Court for N. District of California, San Jose Division, Jun. 2, 2005. |
Menezes, et al., “CRC Handbook of Applied Cryptography”, Boca Raton, Florida, CRC Press LLC, 1996, pp. 591-634. |
VISA International Service Association's Final Invalidity Contentions for U.S. Pat. No. 6,278,783, filed in Case C04-4143 JW in U.S. District Court for the Northern District of California, San Jose Division, Jun. 28, 2007. |
Meijer and Aki, “Digital Signature Schemes”, May 1982, Extended summary of paper presented at CRYPTO 81, Santa Barbara, CA, Aug. 1981. |
VISA International Service Association's Final Invalidity Contentions for U.S. Pat. No. 6,298,442, filed in Case C04-4143JW in U.S. District Court for the Northern District of California, San Jose Division, Jul. 16, 2007. |
Brickell, et al., “Fast Exponentiation with Precomputation (Extended Abstract)”, Springer-Verlag, 1998. |
Gollman et al., “Redundant Integer Representations and Fast Exponentiation”, Designs, Codes and Cryptography, 7, 135-151, Kluwer Academic Publishers, 1996 Boston, MA. |
Defendant VISA International Service Association's Final Invalidity Contentions for U.S. Pat. No. 6,539,092, filed in Case C04-4143JW, Nov. 21, 2007, in U.S. District Court for N. District of California, San Jose Division, including Exhibits A through C17. |
Bradley, S., Some Applications of Mathematics to the Theory of Communications; PhD Thesis, University of London, 1994. |
ISO—11568-2 and 11568-3, Dec. 1, 1994. |
ANSI X9.24—Derived Unique Key Per Transaction (“DUKPT”), 1998. |
Extracts from Handbook of Applied Cryptography 1997 (sections 2.143 (p. 71), 13.9 (p. 586), and 15.2.1 (pp. 636-637). |
Extracts from PIN Manual—A Guide to the Use of Personal Identification Numbers in Interchange, Interbank Card Association, 1979, p. 61 onwards. |
Blum, L. et al., “A Simple Unpredictable Pseudo-Random Number Generator”, Siam J. Comput., 13(2):364-383, May 1986. |
Related U.S. Appl. No. 11/981,495, filed Oct. 30, 2007, now U.S. Pat. No. 7,792,287, issued Sep. 7, 2010. |
Related U.S. Appl. No. 11/978,364, filed Oct. 29, 2007, now U.S. Pat. No. 7,599,488, issued Oct. 6, 2009. |
Number | Date | Country | |
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20120017089 A1 | Jan 2012 | US |
Number | Date | Country | |
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60091644 | Jul 1998 | US |
Number | Date | Country | |
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Parent | 13010034 | Jan 2011 | US |
Child | 13245054 | US | |
Parent | 11977392 | Oct 2007 | US |
Child | 13010034 | US | |
Parent | 10396975 | Mar 2003 | US |
Child | 11977392 | US | |
Parent | 09347493 | Jul 1999 | US |
Child | 10396975 | US |