DETAILED ACTION
This action is in response amendments filed 2/13/2026. Claims 1, 3-13 and 15 are pending with claims 1 and 15 having been amended.
Priority
Acknowledgment is made of applicant's claim for foreign priority under 35 U.S.C. 119(a)-(d). The certified copy has been received.
Response to Arguments
Applicant's arguments filed 2/13/2026 have been fully considered.
Applicant’s arguments, with respect to the rejection(s) of claim(s) 1 and 15 under 103 that LIU Z-R., et al., "Mediated Semi-Quantum Key Distribution Without Invoking Quantum Measurement" listed on IDS filed 2/7/2022 in view of Vig et al (US 2005/0286723) does not teach “wherein each of the plurality of non-orthogonal quantum states comprises an optical pulse” have been fully considered and are not persuasive.
LIU teaches “wherein each of the plurality of non-orthogonal quantum states comprises an optical pulse” on page 4 chapter 3 “Proposed Scheme” Step 2 i.e. Step 2. After Alice (Bob) receives SA, (SB) respectively, Alice (Bob) generates a sequence of Z-basis particles ZA, = {z1A, Z1A..., ZmA} with the length of m, where the states of ZA (ZB) are randomly chosen from {|0), |1)}. Then, Alice (Bob) randomly reorders all the qubits including ZA (ZB) and SA (SB) to form a new (n+m)-qubit sequence QA, (QB)).
While applicant states Lui’s SQKD is different from QKD because in Liu’s SQKD a third party (TP) transmits two streams of entangled photons but Liu page 1 section 1. introduction states “In order to reduce the quantum burden from the ordinary participants, Boyer et al. [17,18] first proposed two types of semi-quantum key distribution (SQKD) protocols. By definition, the term "semi-quantum environment" includes the "quantum" users (typically servers) who have powerful quantum capabilities and the "classical" users who have only limited quantum capabilities. More precisely, the quantum users have all possible quantum abilities to perform the following operations: (a) produce any quantum state, such as single photons or Bell states, etc., (b) perform any quantum measurement, such as X-basis measurement, Bell measurement, or multi-qubit joint measurement, and (c) store quantum states in a quantum memory. Conversely, the classical users are restricted to perform the following operations: (1) generate Z-basis qubits, {|0), |1)}, (2) measure quantum state in the Z basis, (3) reorder the qubits via different delay lines, and (4) reflect the qubits without disturbance”. This clearly states SQKD is QKD with "quantum" users (typically servers) who have powerful quantum capabilities and the "classical" users who have only limited quantum capabilities. These "classical" users can still generate qubits which is an optical pulse and sent the qubits over a quantum channel.
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(s) 1, 3-13, 15 and 16 are rejected under 35 U.S.C. 103 as being unpatentable over LIU Z-R., et al., "Mediated Semi-Quantum Key Distribution Without Invoking Quantum Measurement" listed on IDS filed 2/7/2022 in view of Vig et al (US 2005/0286723).
With respect to claim 1 Liu teaches a method of performing Quantum Key Distribution for generating a shared secret key, the method comprising
at a first node separate from the, preparing or measuring a plurality of non-orthogonal quantum states, each of the plurality of non-orthogonal quantum states being prepared or measured using a respective one of a first random set of basis states (see Liu page 4 chapter 3 “Proposed Scheme” Step 2 i.e. Step 2. After Alice (Bob) receives SA, (SB) respectively, Alice (Bob) generates a sequence of Z-basis particles ZA, = {z1A, Z1A..., ZmA} with the length of m, where the states of ZA (ZB) are randomly chosen from {|0), |1)}. Then, Alice (Bob) randomly reorders all the qubits including ZA (ZB) and SA (SB) to form a new (n+m)-qubit sequence QA, (QB));
at a second node separate from the first node, preparing or measuring the plurality of non-orthogonal quantum states, each of the plurality of non-orthogonal quantum states being prepared or measured using a respective one of a second set of basis states (see Liu page 4 chapter 3 “Proposed Scheme” Step 2 i.e. Step 2. After Alice (Bob) receives SA, (SB) respectively, Alice (Bob) generates a sequence of Z-basis particles ZA, = {z1A, Z1A..., ZmA} with the length of m, where the states of ZA (ZB) are randomly chosen from {|0), |1)}. Then, Alice (Bob) randomly reorders all the qubits including ZA (ZB) and SA (SB) to form a new (n+m)-qubit sequence QA, (QB)); and
at a third node separate from the first and second node, obtaining an indication of the first set of basis states from the first node (see Liu page 4 chapter 3 “After the above preparation, Alice (Bob) sends the sequence Q (Qs) back to TP. Note that the number of the Bell states produced by TP, n, and the number of Z-basis photons generated by Alice and Bob, m, are variable that can be adjusted according to demanded key efficiency and the detection rate).
at a fourth node separate from the first node, the second node, obtaining an indication of the second random set of basis states from the second node (see Liu page 4 chapter 3 “After the above preparation, Alice (Bob) sends the sequence Q (Qs) back to TP. Note that the number of the Bell states produced by TP, n, and the number of Z-basis photons generated by Alice and Bob, m, are variable that can be adjusted according to demanded key efficiency and the detection rate);
wherein each of the plurality of non-orthogonal quantum states comprises an optical pulse (see Liu page 4 chapter 3 “Proposed Scheme” Step 2 i.e. Step 2. After Alice (Bob) receives SA, (SB) respectively, Alice (Bob) generates a sequence of Z-basis particles ZA, = {z1A, Z1A..., ZmA} with the length of m, where the states of ZA (ZB) are randomly chosen from {|0), |1)}. Then, Alice (Bob) randomly reorders all the qubits including ZA (ZB) and SA (SB) to form a new (n+m)-qubit sequence QA, (QB)).
Liu does not teach the fourth node is separate from the third and performing a key agreement stage between the third node and the fourth node to agree upon the shared secret key, the key agreement stage involving the first random set of basis states and the second random set of basis states.
Vig teaches the fourth node is separate from the third (see Vig figure 2 and paragraph 0016 i.e. to extend the distance over which the key can be transmitted, one can use an intermediate relay station. The simplest embodiment of this configuration is the prior art QKD system network 20 shown in FIG. 2. QKD system 20 includes a relay station 30. Relay station 30 has two QKD stations A1 and B1 linked to corresponding QKD stations and figure 5 i.e. B1 and A2); performing a key agreement stage with a fourth node separate from the first node, the second node and the third node to agree upon the shared secret key, the key agreement stage involving the first set of basis states and the second set of basis states (see Vig paragraph 0010 i.e. Alternatively, QKD relays in the network may transport both keying material and message traffic. In essence, this approach uses QKD as a link encryption mechanism, or stitches together an overall end-to-end traffic path from a series of QKD-protected tunnels. Such QKD networks have advantages that overcome the drawbacks of point-to-point links enumerated above and paragraph 0038-0039 i.e. After key k3 is established between stations B1 and A2, then in 714, station B1 forms and records mb1=k1 XOR k3 and erases k1 and k3, and in 716 station A2 forms and records ma2=k3 XOR k2, and erases k3 and k2. Finally, in 718, the secret key S is transmitted from P1 to P2 over public channel links A1-B1, B1-A2, A2-B2. The P1-A1 site sends ca1=S XOR k1 to B1, B1 creates cb1=ca1 XOR mb1 and sends it to A2. A2 then creates ca2=cb1 XOR ma2 and sends it to B2. At the B2-P2 site, the final operation ca2 XOR k2 yields S. Unlike the prior art (see, e.g., C. Elliot, New Journal of Physics 4 (2002) 46.1-46.12, referenced above), the secret key S is not revealed in the clear at each intermediate station).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Liu in view of Vig to have used Vig’s intermediate relay stations to extend the distance over which the key can be transmitted (see Vig paragraph 0009-0011). Therefore one would have been motivated to have used Vig’s quantum key establishment process in which respective quantum keys are agreed between every other node in a path between the P1 and P2 in order to establish a quantum key as a way to extend the distance over which the key can be transmitted.
With respect to claim 3 Liu in view of Vig teaches the method according to claim 1 further comprising, at the third node, obtaining the first set of basis states from the first node via an optical link (see Liu page 1 i.e. Quantum Key distribution (QKD) protocols enable participants to share a secure session key between each other based on quantum mechanics).
With respect to claim 4 Liu in view of Vig teaches the method according to claim 1, further comprising transmitting, from the first node to the third node, an indication of bit values encoded onto the plurality of non-orthogonal quantum states (see Liu page 4 chapter 3 “Proposed Scheme” Step 2 i.e. Step 2. After Alice (Bob) receives SA, (SB) respectively, Alice (Bob) generates a sequence of Z-basis particles ZA, = {z1A, Z1A..., ZmA} with the length of m, where the states of ZA (ZB) are randomly chosen from {|0), |1)}. Then, Alice (Bob) randomly reorders all the qubits including ZA (ZB) and SA (SB) to form a new (n+m)-qubit sequence QA, (QB)).
With respect to claim 5 Liu in view of Vig teaches the method according to claim 1, further comprising transmitting, from the first node to the third node, an indication of a time of transmission of the plurality of non-orthogonal quantum states from the first node (see Liu page 4 chapter 3 “Proposed Scheme” Step 2 i.e. Step 2. After Alice (Bob) receives SA, (SB) respectively, Alice (Bob) generates a sequence of Z-basis particles ZA, = {z1A, Z1A..., ZmA} with the length of m, where the states of ZA (ZB) are randomly chosen from {|0), |1)}. Then, Alice (Bob) randomly reorders all the qubits including ZA (ZB) and SA (SB) to form a new (n+m)-qubit sequence QA, (QB)).
With respect to claim 6 Liu in view of Vig teaches the method according to claim 4, wherein the transmissions between the first node and the third node nodes are encrypted (see Liu page 6-7 chapter 4.2.1.1 i.e. Then, the TP (quantum server) has to decide a session key, SK, for both classical participants and encrypt it using the secret keys).
With respect to claim 7 Liu in view of Vig teaches the method according to claim 6, wherein the encryption is symmetric key encryption (see Liu page 6-7 chapter 4.2.1.1 The Extension of Zou and Qio et al SQKD i.e. Then, the TP (quantum server) has to decide a session key, SK, for both classical participants and encrypt it using the secret keys).
With respect to claim 8 Liu in view of Vig teaches the method according to claim 1, further comprising performing an authentication check between the third node and the fourth node (see Liu page 6-7 chapter 4.2.1.1 The Extension of Zou and Qio et al SQKD i.e. First, Zou and Qiu et al.’s scheme has to be executed twice to let the TP (the quantum server) share a secret key (say Ky4 or Kg) with each classical user (Alice or Bob) respectively).
With respect to claim 9 Liu in view of Vig teaches the method according to claim 1, wherein the third node and the fourth node perform encrypted communication with each other using the shared quantum key (see Liu page 6-7 chapter 4.2.1.1 i.e. Then, the TP (quantum server) has to decide a session key, SK, for both classical participants and encrypt it using the secret keys).
With respect to claim 10 Liu in view of Vig teaches the method according to claim 1, further comprising transmitting, from the second node to the fourth node, an indication of which of the second set of basis states were used to measure the plurality of non-orthogonal quantum states (see Liu page 4 chapter 3 “Proposed Scheme” Step 1 i.e. step 1 TP prepares n | ϕ10 Bell states. Then, TP divides them into two sequences: SA = {q11, q21,..., qn1} and Step 3. Upon receiving QA and QB from Alice and Bob, TP performs Bell measurements on the particle pairs (the i-th pair is formed by taking the i-th particles from QA).
With respect to claim 11 Liu in view of Vig teaches the method according to claim 10, wherein the transmitting takes place over an optical fiber (see Liu page 1 i.e. Quantum Key distribution (QKD) protocols enable participants to share a secure session key between each other based on quantum mechanics).
With respect to claim 12 Liu in view of Vig teaches the method according to claim 10, further comprising encrypting the indication of which of the second set of basis states were used to measure the plurality of non-orthogonal quantum states (see Liu page 4 chapter 3 “Proposed Scheme” Step 1: "SB = q12, q22,…qn2” and Step 3: “TP performs Bell measurements on the particle pairs ... In the sequences ... QB")).
With respect to claim 13 Liu in view of Vig teaches the method according to claim 1, further comprising transmitting, from the second node to the fourth node, an indication of the measured bit values of the plurality of non-orthogonal quantum states (see Liu page 6-7 chapter 4.2.1.1 The Extension of Zou and Qio et al SQKD i.e. In the extension version of SQKD scheme, the resource re- quired between the TP and Alice (Bob) is the same as those of the original Zou and Qiu et al.’s SQKD, including a quantum channel, an authenticated classical channel, 4n single photons generated by the TP, and 4n single photons generated by the Al- ice (Bob). Thus, in the extension version, the total number of quantum channels is 2; the total number of authenticated clas- sical channels is 2; and the total number of single photons is 16n. Moreover, to share an n-bit key in the extension version, Zou and Qiu et al.’s SQKD has to be implemented twice. Hence, the qubit efficiency of the extension version is half of the original one).
With respect to claim 15 Liu teaches an arrangement for performing Quantum Key Distribution (QKD) in order to generate a shared secret key, the arrangement comprising:
a first node and a second node separate from the first node, the first node being adapted to prepare or measure a plurality of non-orthogonal quantum states using a respective one of a first set of basis states, the second node being adapted to prepare or measure a plurality of non-orthogonal quantum states using a respective one of a random second set of basis states (see Liu page 4 chapter 3 “Proposed Scheme” Step 2 i.e. Step 2. After Alice (Bob) receives SA, (SB) respectively, Alice (Bob) generates a sequence of Z-basis particles ZA, = {z1A, Z1A..., ZmA} with the length of m, where the states of ZA (ZB) are randomly chosen from {|0), |1)}. Then, Alice (Bob) randomly reorders all the qubits including ZA (ZB) and SA (SB) to form a new (n+m)-qubit sequence QA, (QB)),
the arrangement further comprising a third node and a fourth node, the third node separate from the first node, the second node being adapted to obtain an indication of the first random set of basis states from the first node, the fourth node being adapted to obtain an indication of the second random set of basis states from the second node, (see Liu figure 2 untrusted TP and page 4 chapter 3 “After the above preparation, Alice (Bob) sends the sequence Q (Qs) back to TP. Note that the number of the Bell states produced by TP, n, and the number of Z-basis photons generated by Alice and Bob, m, are variable that can be adjusted according to demanded key efficiency and the detection rate), and
wherein each of the plurality of non-orthogonal quantum states comprises an optical pulse (see Liu page 4 chapter 3 “Proposed Scheme” Step 2 i.e. Step 2. After Alice (Bob) receives SA, (SB) respectively, Alice (Bob) generates a sequence of Z-basis particles ZA, = {z1A, Z1A..., ZmA} with the length of m, where the states of ZA (ZB) are randomly chosen from {|0), |1)}. Then, Alice (Bob) randomly reorders all the qubits including ZA (ZB) and SA (SB) to form a new (n+m)-qubit sequence QA, (QB)).
Liu does not teach the fourth node is separate from the third and performing a key agreement stage between the third node and the fourth node to agree upon the shared secret key, the key agreement stage involving the first random set of basis states and the second random set of basis states.
.
Vig teaches the fourth node is separate from the third (see Vig figure 2 and paragraph 0016 i.e. to extend the distance over which the key can be transmitted, one can use an intermediate relay station. The simplest embodiment of this configuration is the prior art QKD system network 20 shown in FIG. 2. QKD system 20 includes a relay station 30. Relay station 30 has two QKD stations A1 and B1 linked to corresponding QKD stations and figure 5 i.e. B1 and A2); performing a key agreement stage between the third node and the fourth node to agree upon the shared secret key, the key agreement stage involving the first random set of basis states and the second random set of basis states (see Vig paragraph 0010 i.e. Alternatively, QKD relays in the network may transport both keying material and message traffic. In essence, this approach uses QKD as a link encryption mechanism, or stitches together an overall end-to-end traffic path from a series of QKD-protected tunnels. Such QKD networks have advantages that overcome the drawbacks of point-to-point links enumerated above and paragraph 0038-0039 i.e. After key k3 is established between stations B1 and A2, then in 714, station B1 forms and records mb1=k1 XOR k3 and erases k1 and k3, and in 716 station A2 forms and records ma2=k3 XOR k2, and erases k3 and k2. Finally, in 718, the secret key S is transmitted from P1 to P2 over public channel links A1-B1, B1-A2, A2-B2. The P1-A1 site sends ca1=S XOR k1 to B1, B1 creates cb1=ca1 XOR mb1 and sends it to A2. A2 then creates ca2=cb1 XOR ma2 and sends it to B2. At the B2-P2 site, the final operation ca2 XOR k2 yields S. Unlike the prior art (see, e.g., C. Elliot, New Journal of Physics 4 (2002) 46.1-46.12, referenced above), the secret key S is not revealed in the clear at each intermediate station).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Liu in view of Vig to have used Vig’s intermediate relay stations to extend the distance over which the key can be transmitted (see Vig paragraph 0009-0011). Therefore one would have been motivated to have used Vig’s quantum key establishment process in which respective quantum keys are agreed between every other node in a path between the P1 and P2 in order to establish a quantum key as a way to extend the distance over which the key can be transmitted.
Prior Art
Berzanskis et al (US 2006/0212936) titled “Method Of Integrating QKD With IPSec”.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to DEVIN E ALMEIDA whose telephone number is (571)270-1018. The examiner can normally be reached on Monday-Thursday from 7:30 A.M. to 5:00 P.M. The examiner can also be reached on alternate Fridays from 7:30 A.M. to 4:00 P.M.
If attempts to reach the examiner by telephone are unsuccessful, the examiner's supervisor, Rupal Dharia, can be reached on 571-272-3880. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/DEVIN E ALMEIDA/Examiner, Art Unit 2492
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