DETAILED ACTION
This action is in response to the amendment filed on January 2, 2026. Claims 1, 6-7, 8-10, 13, 17, 19, 21, and 23 have been amended. Claims 2, 3, 11-12, 18, 20, 22, and 24 have been canceled. Claims 25-32 are new. Claims 1, 4-10, 13-17, 19, 21, 23, and 25-32 are pending. Of such, claims 1, 4-10, 13-16, 21, 23, 25-27, and 30-32 represent apparatus’ and claims 17, 19 and 28-29 represent methods directed to implementing quantum key distribution in a data center environment.
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 .
Response to Arguments
Applicant’s arguments and amendments filed on January 2, 2026 with respect to the rejection(s) of claim(s) 1-24 under 35 USC 102 and 103 have been fully considered and are persuasive. Therefore, the rejection has been withdrawn. However, upon further consideration, a new ground(s) of rejection is made in view of Ma and Vest.
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 (i.e., changing from AIA to pre-AIA ) 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.
Claim(s) 1, 5-10, 14-17, 19, 21, 23, and 25-32 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Ma et al. (NPL: Quantum key Distribution with a Hand-Held Sender Unit), hereinafter referred to as Ma.
Regarding Claim 1, Ma discloses:
A quantum transmitter for use in quantum key distribution (QKD) (In section 3.1, Ma discloses “Fig. 4 shows a schematic diagram of our fiber-based BB84 QKD system, which uses a pair of our PCBs to process the data at a continuous high data rate [13] to create a shared sifted key according to the BB84 protocol.”), the quantum transmitter comprising: a light source configured to generate photons at an operational wavelength of around 850 nm, wherein the light source is an on-chip semiconductor laser (In section 1, Ma discloses “For LANs, our 850 nm QKD system is a good choice, since it uses low-cost Vertical Cavity Surface Emitting Laser (VCSEL) and Silicon avalanche photon detectors (Si-APDs).”); quantum state preparation circuitry operatively coupled to the light source and configured to (In section 1, Ma discloses “To provide that support we designed and implemented a programmable set of custom high-speed data handling printed circuit boards.”): receive a sequence of bits (In section 2.1, Ma discloses “The first stage is the transmission of the randomly encoded single photon stream from Alice (the sender) to Bob (the receiver) through an unsecured public link (called the quantum channel) to establish the raw key.”); map the bits to respective quantum states and measurement bases (In section 2.1, Ma discloses “In the BB84 system, each photon is set in one of the four linear polarization states: horizontal-vertical (belonging to the horizontal-vertical basis) or +/- 45 degree diagonal (belonging to the diagonal basis). One of the polarization states in each basis represents a “0” bit value and the other a “1”.”); and encode the quantum states onto respective photons based on the measurement bases to generate qubits (In section 3.3, Ma discloses “The next step is to have Alice continuously send quantum packets containing a known, fixed four photon pattern, all photons are encoded in the same state.”); and a quantum channel interface operatively coupled to the quantum state preparation circuitry (In section 2.2, Ma discloses “Each packet is then passed to the Transmit/Receive module where they are synchronously sent to Bob on the quantum channel along with a “Sync” message on the classical channel.”) and configured to transmit the qubit to a quantum receiver via an optical fiber quantum communication channel (In section 2.2 Ma discloses “When a “Sync” message is received by the Transmit/Receive module in Bob’s FPGA, it begins the capture of one packet’s worth of data from the Quantum channels.” And in Section 3.1, Ma further discloses “The single photon attenuation is acceptable over short distances in LAN optical fibers.”).
Regarding Claim 5, Ma discloses:
The quantum transmitter of Claim 1, wherein the quantum transmitter is configured to operate at a room temperature. (In section 5, Ma discloses “Si-APDs are low cost, operate at room temperature and have the highest peak detection efficiency among these detectors”)
Regarding Claim 6, Ma discloses:
The quantum transmitter of Claim 1, further comprising security and protocol management circuitry configured to: transmit, via a classical communication channel, the measurement bases used to encode the bits to the quantum receiver (In section 2.1, Ma discloses “The next three stages of the protocol, common to both BB84 and B92, are conducted over an unsecured public link (called the classical channel, since this can be standard IP communications)… The second stage is sifting, where Bob sends a list back to Alice of photons detected and their basis (measurement state), but not their value.”).
Regarding Claim 7, Ma discloses:
The quantum transmitter of Claim 6, wherein the security and protocol management circuitry is further configured to: receive, from the quantum receiver via the classical communication channel, measurement bases for decoding the qubits (In section 2.1, Ma discloses “Bob randomly chooses to measure the photons in either the horizontal-vertical or diagonal basis… where Bob sends a list back to Alice of photons detected and their basis (measurement state), but not their value.”); and establish a shared encryption key with the quantum receiver using bits and qubits having matching measurement bases (In section 2.1, Ma discloses “Alice and Bob now have a list of sifted keys.”).
Regarding Claim 8, Ma discloses:
The quantum transmitter of Claim 1, wherein a transmission distance between the quantum transmitter and the quantum receiver is less than 2 km. (In section 1, Ma discloses “The LAN is a short distance network (usually less than 5 km) and can use a star/hub configuration.”)
Regarding Claim 9, Ma discloses:
The quantum transmitter of Claim 1, wherein the quantum state preparation circuitry is configured to receive the sequence of bits from a random number generator. (In section 2.2, Ma discloses “The Random Number Generator module on Alice’s FPGA generates two bit-streams of pseudo random data at up to 1.25 Gbit/s; one stream for the bit value and the other for the basis.”)
Regarding Claim 10, Ma discloses:
A quantum receiver for use in quantum key distribution (QKD), the quantum receiver comprising (In section 3.1, Ma discloses “Fig. 4 shows a schematic diagram of our fiber-based BB84 QKD system, which uses a pair of our PCBs to process the data at a continuous high data rate [13] to create a shared sifted key according to the BB84 protocol.”): a quantum channel interface configured to receive (In section 2.2, Ma discloses “Each packet is then passed to the Transmit/Receive module where they are synchronously sent to Bob on the quantum channel along with a “Sync” message on the classical channel.”), via an optical fiber quantum communication channel, qubits from a quantum transmitter (In section 2.2 Ma discloses “When a “Sync” message is received by the Transmit/Receive module in Bob’s FPGA, it begins the capture of one packet’s worth of data from the Quantum channels.” And in Section 3.1, Ma further discloses “The single photon attenuation is acceptable over short distances in LAN optical fibers.”); a photon detector operatively coupled to the quantum channel interface and configured to detect the qubits at an operational wavelength of around 850 nm (In section 3.5, Ma discloses “After an APD detects a photon, the avalanche process generates an electrical output signal.”), wherein the photon detector is a silicon-based single photon avalanche diode (SPAD) (In section 1, Ma discloses “For LANs, our 850 nm QKD system is a good choice, since it uses low-cost Vertical Cavity Surface Emitting Laser (VCSEL) and Silicon avalanche photon detectors (Si-APDs).”); and quantum state measurement circuitry operatively coupled to the photon detector (In section 5.2, Ma discloses “detection results are sent to Bob’s PCB.”) and configured to: select measurement bases to decode states of the qubits (In section 2.1, Ma discloses “Bob randomly chooses to measure the photons in either the horizontal-vertical or diagonal basis.”); and decode states of the qubits based on the measurement bases (In section 2.1, Ma discloses “If Bob chooses correctly, the value he measures will be correct.”).
Regarding Claim 14, Ma discloses:
The quantum receiver of Claim 10, wherein the quantum receiver is configured to operate at a room temperature. (In section 5, Ma discloses “Si-APDs are low cost, operate at room temperature and have the highest peak detection efficiency among these detectors”)
Regarding Claim 15, Ma discloses:
The quantum receiver of Claim 10, further comprising security and protocol management circuitry configured to: transmit, to the quantum transmitter via a classical communication channel, the measurement bases used to decode the qubits (In section 2.1, Ma discloses “The next three stages of the protocol, common to both BB84 and B92, are conducted over an unsecured public link (called the classical channel, since this can be standard IP communications)… The second stage is sifting, where Bob sends a list back to Alice of photons detected and their basis (measurement state), but not their value.”).
Regarding Claim 16, Ma discloses:
The quantum receiver of Claim 15, wherein the security and protocol management circuitry is further configured to: receive, from the quantum transmitter via the classical communication channel, a measurement bases used to encode the bits (In section 2.1, Ma discloses “Bob randomly chooses to measure the photons in either the horizontal-vertical or diagonal basis… where Bob sends a list back to Alice of photons detected and their basis (measurement state), but not their value.”) and establish a shared encryption key with the quantum transmitter using bits and qubits with matching measurement bases (In section 2.1, Ma discloses “Alice and Bob now have a list of sifted keys.”).
Claim 17 is directed to a method having functionality corresponding to the system of Claim 1, and is rejected by a similar rationale, mutatis mutandis.
Claim 19 is directed to a method having functionality corresponding to the system of Claim 10, and is rejected by a similar rationale, mutatis mutandis.
Regarding Claim 21, Ma discloses:
A quantum transmitter for use in quantum key distribution (QKD) (In section 3.1, Ma discloses “Fig. 4 shows a schematic diagram of our fiber-based BB84 QKD system, which uses a pair of our PCBs to process the data at a continuous high data rate [13] to create a shared sifted key according to the BB84 protocol.”), the quantum transmitter comprising: a light source configured to generate photons at an operational wavelength of around 850 nm, wherein the light source is an on-chip semiconductor laser (In section 1, Ma discloses “For LANs, our 850 nm QKD system is a good choice, since it uses low-cost Vertical Cavity Surface Emitting Laser (VCSEL) and Silicon avalanche photon detectors (Si-APDs).”); quantum state preparation circuitry operatively coupled to the light source and configured to: receive a sequence of bits (In section 2.1, Ma discloses “The first stage is the transmission of the randomly encoded single photon stream from Alice (the sender) to Bob (the receiver) through an unsecured public link (called the quantum channel) to establish the raw key.”); map the bits to respective quantum states and measurement bases (In section 2.1, Ma discloses “In the BB84 system, each photon is set in one of the four linear polarization states: horizontal-vertical (belonging to the horizontal-vertical basis) or +/- 45 degree diagonal (belonging to the diagonal basis). One of the polarization states in each basis represents a “0” bit value and the other a “1”.”); and encode the quantum states onto respective photons based on the measurement bases to generate a corresponding qubits (In section 3.3, Ma discloses “The next step is to have Alice continuously send quantum packets containing a known, fixed four photon pattern, all photons are encoded in the same state.”); and a quantum channel interface operatively coupled to the quantum state preparation circuitry (In section 2.2, Ma discloses “Each packet is then passed to the Transmit/Receive module where they are synchronously sent to Bob on the quantum channel along with a “Sync” message on the classical channel.”) and configured to transmit the qubits to a quantum receiver via optical fiber quantum communication channel (In section 2.2 Ma discloses “When a “Sync” message is received by the Transmit/Receive module in Bob’s FPGA, it begins the capture of one packet’s worth of data from the Quantum channels.” And in Section 3.1, Ma further discloses “The single photon attenuation is acceptable over short distances in LAN optical fibers.”), wherein a transmission distance between the quantum transmitter and the quantum receiver is less than 2 km (In section 1, Ma discloses “The LAN is a short distance network (usually less than 5 km) and can use a star/hub configuration.”).
Regarding Claim 23, Ma discloses:
A quantum receiver for use in quantum key distribution (QKD) (In section 3.1, Ma discloses “Fig. 4 shows a schematic diagram of our fiber-based BB84 QKD system, which uses a pair of our PCBs to process the data at a continuous high data rate [13] to create a shared sifted key according to the BB84 protocol.”), the quantum receiver comprising: a quantum channel interface configured to receive (In section 2.2, Ma discloses “Each packet is then passed to the Transmit/Receive module where they are synchronously sent to Bob on the quantum channel along with a “Sync” message on the classical channel.”), via an optical fiber quantum communication channel, qubits from a quantum transmitter (In section 2.2 Ma discloses “When a “Sync” message is received by the Transmit/Receive module in Bob’s FPGA, it begins the capture of one packet’s worth of data from the Quantum channels.” And in Section 3.1, Ma further discloses “The single photon attenuation is acceptable over short distances in LAN optical fibers.”); a photon detector operatively coupled to the quantum channel interface and configured to detect the qubits at an operational wavelength of around 850 nm (In section 3.5, Ma discloses “After an APD detects a photon, the avalanche process generates an electrical output signal.”), wherein the photon detector is a silicon-based single photon avalanche diode (SPAD) (In section 1, Ma discloses “For LANs, our 850 nm QKD system is a good choice, since it uses low-cost Vertical Cavity Surface Emitting Laser (VCSEL) and Silicon avalanche photon detectors (Si-APDs).”); and quantum state measurement circuitry operatively coupled to the photon detector and configured to: select a measurement bases to decode states of qubits (In section 2.1, Ma discloses “Bob randomly chooses to measure the photons in either the horizontal-vertical or diagonal basis.”) and decode the states of the qubits based on the measurement bases (In section 2.1, Ma discloses “If Bob chooses correctly, the value he measures will be correct.”).
Regarding Claim 25, Ma discloses:
The quantum transmitter of Claim 1, wherein the quantum transmitter is configured to operate in a data center environment. (In section 1, Ma discloses “We have developed several technologies to integrate QKD into these network categories. For LANs, our 850 nm QKD system is a good choice, since it uses low-cost Vertical Cavity Surface Emitting Laser (VCSEL) and Silicon avalanche photon detectors (Si-APDs).”)
Regarding Claim 26, Ma discloses:
The quantum transmitter of Claim 1, wherein the on-chip semiconductor laser is a vertical-cavity surface-emitting laser (VCSEL). (In section 1, Ma discloses “We have developed several technologies to integrate QKD into these network categories. For LANs, our 850 nm QKD system is a good choice, since it uses low-cost Vertical Cavity Surface Emitting Laser (VCSEL) and Silicon avalanche photon detectors (Si-APDs).”)
Regarding Claim 27, Ma discloses:
The quantum receiver of Claim 10, wherein the quantum receiver is configured to operate in a data center environment. (In section 1, Ma discloses “We have developed several technologies to integrate QKD into these network categories. For LANs, our 850 nm QKD system is a good choice, since it uses low-cost Vertical Cavity Surface Emitting Laser (VCSEL) and Silicon avalanche photon detectors (Si-APDs).”)
Regarding Claim 28, Ma discloses:
The method of Claim 17, wherein the quantum transmitter is configured to operate in a data center environment. (In section 1, Ma discloses “We have developed several technologies to integrate QKD into these network categories. For LANs, our 850 nm QKD system is a good choice, since it uses low-cost Vertical Cavity Surface Emitting Laser (VCSEL) and Silicon avalanche photon detectors (Si-APDs).”)
Regarding Claim 29, Ma discloses:
The method of Claim 19, wherein the quantum receiver is configured to operate in a data center environment. (In section 1, Ma discloses “We have developed several technologies to integrate QKD into these network categories. For LANs, our 850 nm QKD system is a good choice, since it uses low-cost Vertical Cavity Surface Emitting Laser (VCSEL) and Silicon avalanche photon detectors (Si-APDs).”)
Regarding Claim 30, Ma discloses:
The quantum transmitter of Claim 21, wherein the quantum transmitter is configured to operate in a data center environment. (In section 1, Ma discloses “We have developed several technologies to integrate QKD into these network categories. For LANs, our 850 nm QKD system is a good choice, since it uses low-cost Vertical Cavity Surface Emitting Laser (VCSEL) and Silicon avalanche photon detectors (Si-APDs).”)
Regarding Claim 31, Ma discloses:
The quantum transmitter of Claim 21, wherein the quantum transmitter is configured to operate at room temperature. (In section 5, Ma discloses “Si-APDs are low cost, operate at room temperature and have the highest peak detection efficiency among these detectors”)
Regarding Claim 32, Ma discloses:
The quantum receiver of Claim 23, wherein the quantum receiver is configured to operate in a data center environment. (In section 1, Ma discloses “We have developed several technologies to integrate QKD into these network categories. For LANs, our 850 nm QKD system is a good choice, since it uses low-cost Vertical Cavity Surface Emitting Laser (VCSEL) and Silicon avalanche photon detectors (Si-APDs).”)
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.
Claims 4 and 13 are rejected under 35 U.S.C. 103 as being unpatentable Ma et al. (NPL: Quantum key Distribution with a Hand-Held Sender Unit), hereinafter referred to as Ma., in view of Vest et al. (NPL: Quantum key Distribution with a Hand-Held Sender Unit), hereinafter referred to as Vest.
Regarding Claim 4, Ma discloses the limitations with respect to claim 1.
However, Ma does not explicitly disclose the small form factor of the devices.
Vest discloses:
The quantum transmitter of Claim 1, wherein the quantum transmitter has a small form factor that is less than 40 cm3 in volume. (On page 2, Vest discloses “In this work we combine these technological advances in miniaturizing all optical and electronic components for a hand-held QKD transmitter module...The assembled optical module has a size of 35 × 20 × 8 mm where the large lateral extension is mainly determined by the footprint of the electric connector and of the printed circuit board (PCB, 20 × 6 mm) onto which the VCSEL array is mounted”)
One in ordinary skill in the art of cryptography would have been motivated, before the effective filing date of the claimed invention to modify Ma’s approach by utilizing Vest’s approach of using a small form factor for the transmitter as the motivation would be to allow for a hand-held and mobile friendly quantum key distribution system that allows for short distance distribution (See Vest, Abstract).
Regarding Claim 13, Ma discloses the limitations with respect to claim 10.
However, Ma does not explicitly disclose the small form factor of the devices.
Vest discloses:
The quantum receiver of Claim 10, wherein the quantum receiver has a small form factor that is less than 40 cm3 in volume. (On page 2, Vest discloses “In this work we combine these technological advances in miniaturizing all optical and electronic components for a hand-held QKD…The operating wavelength of 850 nm provides high transmission through the atmosphere for free-space applications and a wide availability of inexpensive, high-efficiency single-photon detectors operating at noncryogenic temperatures.” Further, see Figure 1(a) wherein the receiver is shown as smaller than the transmitter, thus having a smaller form factor than the transmitter that is hand-held)
One in ordinary skill in the art of cryptography would have been motivated, before the effective filing date of the claimed invention to modify Ma’s approach by utilizing Vest’s approach of using a small form factor for the receiver as the motivation would be to allow for a hand-held and mobile friendly quantum key distribution system that allows for short distance distribution (See Vest, Abstract).
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Lee et a. (US 20250247219) discloses a method for quantum key distribution utilizing a silicon based receiver operating at 850nm.
Iqbal et al. (US 20240162992) discloses a method for quantum key generation using photon receivers.
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 SHADI H KOBROSLI whose telephone number is (571)272-1952. The examiner can normally be reached M-F 9am-5pm ET.
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/SHADI H KOBROSLI/Examiner, Art Unit 2492 /RUPAL DHARIA/Supervisory Patent Examiner, Art Unit 2492