DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 1-2, 4-5, 7-12, 14-20 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 1 recites the limitation "the first message or the second message" in line 18 of Claim 1. There is insufficient antecedent basis for this limitation in the claim. That is, when the claims recite “the first message” and “the second message” in line 18 of Claim 1, Claim 1 previously recites “a first message or a second message” in line 1, “a first oblivious transfer message” in lines 3-4 and “a second oblivious transfer message” in line 9, and “a first obfuscated message and a second obfuscated message” in lines 12-13. For this reason, “the first message” and “the second message” lack antecedent basis as they could refer to three different message pairs, rendering the claim indefinite. It is recommended by the Examiner to distinguish this pair of messages, such as by referring to these messages as a first plaintext message and a second plaintext message corresponding to the obfuscated messages.
Claims 2, 4-5, 7-11 are rejected by virtue of depending upon Claim 1. Claim 12 is rejected for similar reasons as Claim 1 as it recites similar limitations as Claim 1. Claims 14-19 are rejected by virtue of depending upon Claim 12. Claim 20 is rejected for similar reasons as Claim 1 as it recites similar limitations as Claim 1.
Claim Rejections - 35 USC § 102
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
Claims 1-2, 4-5, 7-12, 14-19 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Tzeng et al. (NPL – “Efficient 1-Out-n Oblivious Transfer Schemes”), hereinafter referred to as “Tzeng”.
Regarding Claim 1:
Tzeng teaches the following limitations:
A method for obliviously transferring either a first message or a second message to a receiver computer, the method comprising: receiving, by the receiver computer, from a sender computer, a first oblivious transfer message [send parameters] (Introduction, Page 159; Section 2.2). Tzeng teaches oblivious transfer protocols, generalizing the 1-out-2 oblivious transfer to the 1-out-n case. The specific case of the 1-out-2 oblivious transfer according to the algorithm of Tzeng is substantially equivalent to the claimed invention. Tzeng teaches a sender transmitting initial parameters as a step 0, i.e. a first oblivious transfer message.
determining, by the receiver computer, a first random number [randomly select r] (Section 2.1, Pages 163-164). Tzeng teaches the receiver picking a random number r.
retrieving, by the receiver computer, a receiver choice bit [R’s choice α], wherein the receiver choice bit is unknown to the sender computer (Section 2.1, Page 163). Tzeng teaches the receiver choosing a message through a parameter α. In the case of the 1-out-2 oblivious transfer, this can only be one of two values, i.e. a choice bit.
generating, by the receiver computer, based on the first oblivious transfer message, the first random number, and the receiver choice bit, a second oblivious transfer message [R sends y] (Section 2.3, Page 164). Tzeng teaches the receiver generating and sending a message, y, which is constructed using the previous parameters.
transmitting, by the receiver computer, to the sender computer, the second oblivious transfer message (Section 2.3, Page 164).
wherein the sender computer generates a third oblivious transfer message using the second oblivious transfer message, wherein the third oblivious transfer message [ci] comprises a first obfuscated message and a second obfuscated message [mi] (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165). Tzeng teaches the sender generating and sending ci values which are constructed from mi values, secrets/messages which are obfuscated using a hash function as in section 2.3.
receiving, by the receiver computer, from the sender computer, the third oblivious transfer message (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
and generating, by the receiver computer, an output message by de-obfuscating the first obfuscated message or the second obfuscated message, wherein the output message is equivalent to either the first message or the second message [R computes mα] (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165). Tzeng teaches the receiver calculating mα, i.e. the message corresponding to the choice bit.
wherein the first oblivious transfer message comprises a first group element [g] and a second group element [h] (Section 2.1, Page 162; Section 2.2). Tzeng teaches the parameters being generators g and h, group elements of an order-q group where q is prime.
wherein the sender computer generates the first group element and the second group element by randomly sampling the first group element and the second group element from a group (Section 2.1, Page 162; Section 2.2). Tzeng teaches these parameters being chosen from the group.
and the third oblivious transfer message additionally comprises a third group element [a = gki] (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165). Tzeng teaches a third group element in the form of an exponentiated form of g using a random exponent k_i. Note that this random number of Tzeng can be the same for both messages, and this is done similarly in Naor et al. (NPL “Efficient Oblivious Transfer Protocols”, Page 451, Col. 2) hereinafter referred to as “Naor”
the sender computer determines a second random number (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
the sender computer generates the third group element using the first group element and the second random number (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
the sender computer generates the first obfuscated message using a hash function [H], an intermediate group element [y], the second random number [ki], and the first message [mi] (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165). Tzeng uses a hash function to obfuscate the messages.
and the sender computer generates the second obfuscated message using the hash function, the intermediate group element, the second group element, the second random number, and the second message (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
Regarding Claim 2:
Tzeng teaches the following limitations:
wherein if the receiver choice bit is zero or false, in the method, the receiver computer selects the first obfuscated message (Section 2.1, Pages 162-164; Section 2.3, Pages 164-165). Tzeng teaches the message being selected according to the value of α. While Tzeng uses 1-indexing to describe their algorithm for the 1-out-n oblivious transfer, one of ordinary skill in the art would have recognized that the algorithm of Tzeng is still operable with 0-indexing, and in the specific case of the 1-out-2 oblivious transfer, this corresponds to α being 0 or 1. This is further supported by Naor (Naor, Section 2.3, Page 450).
and wherein if the receiver choice bit is one or true, the receiver computer selects the second obfuscated message, thereby determining a selected obfuscated message, wherein the output message is generated by de-obfuscating the selected obfuscated message (Section 2.1, Pages 162-164; Section 2.3, Pages 164-165).
Regarding Claim 4:
Tzeng teaches the following limitations:
wherein the group is a cyclic group defined by a prime number [q] (Section 2.1, Page 162; Section 2.2). The group corresponds to a prime number q, making the group cyclic.
Regarding Claim 5:
Tzeng teaches the following limitations:
wherein the second oblivious transfer message comprises the intermediate group element (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165). Previously, the value y was drawn to the intermediate group element and the second oblivious transfer message.
and wherein generating, by the receiver computer, the second oblivious transfer message comprises: generating, by the receiver computer, a first exponentiated group element by exponentiating the first group element using the first random number [gr] (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
generating, by the receiver computer, a second exponentiated group element by exponentiating the second group element using an additive inverse of the receiver choice bit [hα] (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165). Tzeng teaches exponentiating a group element according to the receiver bit. One of ordinary skill in the art however would have recognized that a group element has a unique corresponding inverse, and as the group elements are randomly chosen, this is mathematically equivalent to what is claimed.
and generating, by the receiver computer, the intermediate group element by determining a product of the first exponentiated group element and the second exponentiated group element (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165). These values are multiplied together in Tzeng.
Regarding Claim 7:
Tzeng teaches the following limitations:
wherein the receiver computer samples the first random number from an interval of integers defined by a prime number and wherein the sender computer samples the second random number from the interval of integers defined by the prime number (Section 2.1, Page 162; Section 2.2).
Regarding Claim 8:
Tzeng teaches the following limitations:
wherein the sender computer generates the third group element by exponentiating the first group element using the second random number (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
Regarding Claim 9:
Tzeng teaches the following limitations:
wherein the sender computer generates the first obfuscated message by: exponentiating the intermediate group element using the second random number, thereby generating an exponentiated intermediate group element (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165). Tzeng teaches exponentiating the value y using the second random number.
generating a first hash by inputting the exponentiated intermediate group element into the hash function (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165). This exponentiated value is used as part of the input for the hash function.
and generating the first obfuscated message by computing an XOR of the first hash and the first message (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165). Tzeng teaches using a bitwise XOR.
Regarding Claim 10:
Tzeng teaches the following limitations:
wherein the sender computer generates the second obfuscated message by: computing a product of the intermediate group element and the second group element (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165). Tzeng teaches an analogous process of generating the first obfuscated message for generating the second obfuscated message.
generating an exponentiated product by exponentiating the product of the intermediate group element and the second group element using the second random number (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
generating a second hash by inputting the exponentiated product into the hash function (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
and generating the second obfuscated message by computing an XOR of the second hash and the second message (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
Regarding Claim 11:
Tzeng teaches the following limitations:
wherein generating, by the receiver computer, the output message comprises: exponentiating, by the receiver computer, the third group element using the first random number, thereby generating an exponentiated third group element [ar] (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165). Tzeng teaches exponentiating the third group element, a, by the first random number, r.
generating, by the receiver computer, a third hash by inputting the exponentiated third group element into the hash function (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165). This resulting value is hashed.
and generating, by the receiver computer, the output message by computing an XOR of the third hash and the first obfuscated message and/or the second obfuscated message (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165). This value is used for calculating the output value using the XOR function.
Regarding Claim 12:
Tzeng teaches the following limitations:
A method for obliviously transferring either a first message or a second message to a receiver computer, the method comprising: generating, by a sender computer, a first oblivious transfer message (Introduction, Page 159; Section 2.2).
transmitting, by the sender computer, the first oblivious transfer message to the receiver computer (Section 2.1, Pages 163-164).
wherein the receiver computer determines a first random number, retrieves a receiver choice bit, and generates a second oblivious transfer message based on the first oblivious transfer message, the first random number, and the receiver choice bit, wherein the receiver choice bit is unknown to the sender computer (Section 2.1, Page 163; Section 2.3, Page 164).
receiving, by the sender computer, from the receiver computer, the second oblivious transfer message (Section 2.3, Page 164).
determining, by the sender computer, a second random number (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
generating, by the sender computer, a third oblivious transfer message based on the second random number and the second oblivious transfer message, wherein the third oblivious transfer message comprises a first obfuscated message and a second obfuscated message (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
and transmitting, by the sender computer, the third oblivious transfer message to the receiver computer, wherein the receiver computer uses the first obfuscated message or the second obfuscated message to generate an output message, wherein the output message comprises either the first message or the second message (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
wherein the first oblivious transfer message comprises a first group element and a second group element (Section 2.1, Page 162; Section 2.2).
wherein the sender computer generates the first group element and the second group element by randomly sampling the first group element and the second group element from a group (Section 2.1, Page 162; Section 2.2).
and the third oblivious transfer message additionally comprises a third group element (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
and wherein the method further comprises: generating, by the sender computer, the third group element using the first group element and the second random number (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
generating, by the sender computer, the first obfuscated message using a hash function, an intermediate group element, the second random number, and the first message (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
and generating, by the sender computer, the second obfuscated message using the hash function, the intermediate group element, the second group element, the second random number, and the second message (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
Regarding Claim 14:
Tzeng teaches the following limitations:
wherein: the second oblivious transfer message comprises the intermediate group element (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
the receiver computer generates a first exponentiated group element by exponentiating the first group element using the first random number (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
the receiver computer generates a second exponentiated group element by exponentiating the second group element using an additive inverse of the receiver choice bit (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
and the receiver computer generates the intermediate group element by computing a product of the first exponentiated group element and the second exponentiated group element (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
Regarding Claim 15:
Tzeng teaches the following limitations:
wherein the method further comprises: generating, by the sender computer, the third group element by exponentiating the first group element using the second random number (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
Regarding Claim 16:
Tzeng teaches the following limitations:
wherein the second oblivious transfer message comprises the intermediate group element (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
and wherein the method further comprises: exponentiating, by the sender computer, the intermediate group element using the second random number, thereby generating an exponentiated intermediate group element (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
generating, by the sender computer, a first hash using the exponentiated intermediate group element and the hash function (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
and generating, by the sender computer, the first obfuscated message by computing an XOR of the first hash and the first message (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
Regarding Claim 17:
Tzeng teaches the following limitations:
wherein the method further comprises: computing, by the sender computer, a product of the intermediate group element and the second group element (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165). As argued in claim 5, as one of ordinary skill in the art would have recognized that a group element uniquely corresponds to an inverse, the product of the group elements as claimed is equivalent to the computation in Tzeng.
generating, by the sender computer, an exponentiated product by exponentiating the product of the intermediate group element and the second group element using the second random number (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
generating, by the sender computer, a second hash using the exponentiated product and the hash function (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
and generating, by the sender computer, the second obfuscated message by computing an XOR of the second hash and the second message (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
Regarding Claim 18:
Tzeng teaches the following limitations:
wherein: the receiver computer generates a third hash using the first random number, the third group element, and the hash function (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165)
and the receiver computer generates the output message by computing an XOR of the first obfuscated message and/or the second obfuscated message and the third hash (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
Regarding Claim 19:
Tzeng teaches the following limitations:
wherein: the receiver computer generates an exponentiated third group element by exponentiating the third group element using the first random number (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
and the receiver computer generates the third hash using the exponentiated third group element and the hash function (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claim 20 is rejected under 35 U.S.C. 103 as being unpatentable over Tzeng in view of Masny et al. (U.S. Pub. No. 2020/0259800 A1) hereinafter referred to as “Masny”.
Regarding Claim 20:
Tzeng teaches the following limitations:
(taught by Masny below)
a method of obliviously transferring either a first message or a second message to the receiver computer, the method comprising receiving, from a sender computer, a first oblivious transfer message (Introduction, Page 159; Section 2.2).
determining a first random number (Section 2.1, Pages 163-164).
retrieving a receiver choice bit, wherein the receiver choice bit is unknown to the sender computer (Section 2.1, Page 163).
generating, based on the first oblivious transfer message, the first random number, and the receiver choice bit, a second oblivious transfer message (Section 2.3, Page 164).
transmitting to the sender computer, the second oblivious transfer message (Section 2.3, Page 164).
wherein the sender computer generates a third oblivious transfer message using the second oblivious transfer message, wherein the third oblivious transfer message comprises a first obfuscated message and a second obfuscated message (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
receiving, from the sender computer, the third oblivious transfer message (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
and generating, an output message by de-obfuscating the first obfuscated message or the second obfuscated message, wherein the output message is equivalent to either the first message or the second message (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
wherein the first oblivious transfer message comprises a first group element and a second group element (Section 2.1, Page 162; Section 2.2).
wherein the sender computer generates the first group element and the second group element by randomly sampling the first group element and the second group element from a group (Section 2.1, Page 162; Section 2.2).
and the third oblivious transfer message additionally comprises a third group element (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
the sender computer determines a second random number (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
the sender computer generates the third group element using the first group element and the second random number (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
the sender computer generates the first obfuscated message using a hash function, an intermediate group element, the second random number, and the first message (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
and the sender computer generates the second obfuscated message using the hash function, the intermediate group element, the second group element, the second random number, and the second message (Section 2.1, Pages 162-163; Section 2.3, Pages 164-165).
Masny teaches the following limitation:
A receiver computer comprising: a processor; and a non-transitory computer readable medium coupled to the processor, the non-transitory computer readable medium comprising code, executable by the processor for implementing (Par. [0129], Par. [0130]). Masny teaches hardware structure for implementing oblivious transfers on a computer system.
Tzeng teaches a method for oblivious transfers, but does not explicitly teach the hardware components for implementing such a method. Masny however describes that a system for oblivious transfers can be implementing using hardware connected to a non-transitory storage medium. Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to combine the oblivious transfer algorithm of Tzeng with the hardware structure of Masny in order to gain the predictable result of using computer hardware to implement the oblivious transfer algorithm described by Tzeng. One of ordinary skill in the art would have realized that the system of Masny is compatible with the algorithm of Tzeng since Masny is also directed to performing oblivious transfers, and that such hardware could be predictably used to implement the oblivious transfer algorithm of Tzeng.
Related Art
The following prior art made of record and cited on PTO-892, but not relied upon, is considered pertinent to applicant’s disclosure:
Tateishi et al. (U.S. Pub. No. 2013/0159696 A1) – Includes methods regarding oblivious transfers
Ramzan et al. (U.S. Pub. No. 2005/0259817 A1) - Includes methods regarding oblivious transfers
Camenisch et al. (U.S. Pub. No. 2011/0145589 A1) - Includes methods regarding oblivious transfers
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ETHAN V VO whose telephone number is (571)272-2505. The examiner can normally be reached M-F 8am-5pm.
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/E.V.V./Examiner, Art Unit 2431 /LYNN D FEILD/Supervisory Patent Examiner, Art Unit 2431
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