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Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE

Quantitative analysis of quantum noise masking in quantum stream cipher by intensity modulation operating at G bit/sec data rate

Takehisa Iwakoshi, Fumio Futami, Osamu Hirota

Published Jan 1, 2011• 0 citations
OpenAlex

Abstract

In any communication system, all data including encrypted data by the mathematical cipher are transmitted under the strict rule of the interface frame. Attacker can easily acquire the whole data the same as the data of legitimate users including the address, routing information and so on from the transmission line by tapping. This is very risky, especially for the secret sharing data center operations. So to hide the whole data in the transmission line is very attractive to ensure the high security level. This can be realized by Y-00 type random cipher that the ciphertext of simple mathematical cipher by PRNG is randomized by quantum noise and it gives a masking effect against the attacker's security analysis. This paper clarifies quantitative properties on the masking effect in the random cipher by Y-00 protocol, and shows the fact that a scheme by the intensity modulation may provide the greatest masking effect, even if the attacker employs the universal heterodyne receiver.

Related papers

Quantitative analysis of quantum noise masking in quantum stream cipher by intensity modulation operating at G-bit/sec data rate

Takehisa Iwakoshi, Fumio Futami, Osamu Hirota

In any communication system, all data including encrypted data by the mathematical cipher are transmitted under the strict rule of the interface frame. Attacker can easily acquire the whole data the same as the data of legitimate users including the address, routing information and so on from the transmission line by tapping. This is very risky, especially for the secret sharing data center operations. So to hide the whole data in the transmission line is very attractive to ensure the high security level. This can be realized by Y-00 type random cipher that the ciphertext of simple mathematical cipher by PRNG is randomized by quantum noise and it gives a masking effect against the attacker's security analysis. This paper clarifies quantitative properties on the masking effect in the random cipher by Y-00 protocol, and shows the fact that a scheme by the intensity modulation may provide the greatest masking effect, even if the attacker employs the universal heterodyne receiver.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Oct 6, 2011•5 citations

Y-00 Quantum-Noise Randomized Stream Cipher Using Intensity Modulation Signals for Physical Layer Security of Optical Communications

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The Internet plays an essential role in modern societies and in the amount of sensitive data transported over the optical networks that shows its' importance has increased drastically. Therefore, it is critical to develop data protection schemes for optical fiber communications to provide user security. The Y-00 quantum-noise randomized stream cipher that employs extremely high-order modulation and restricts an attacker's interception of ciphertext is a practical candidate for providing data protection. In this article, we introduce the operation principle of the Y-00 cipher with respect to data encryption and decryption. The Y-00 cipher combines the mathematical encryption of multi-level signaling and physical randomness, and provides a high level of security to the physical layer of optical communications and a high communication performance. We also present the noise masking phenomenon of the Y-00 cipher with intensity modulation (IM). This noise masking is generated by shot noise, i.e., quantum noise and additive noise such as amplified spontaneous emission noise. The noise masking phenomenon fails an attacker's interception of the ciphertext. The secrecy of the IM Y-00 cipher is also discussed, and an approximate analytical solution is introduced for evaluating the probability of the attackers accurately guessing the ciphertext. Finally, the secrecy of a 1,000-km transmission system is experimentally demonstrated with the Y-00 cipher transceiver at data rate of 1.5-Gb/s using the derived analytical solution to deduce the high secrecy of the entire transmission system.

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Quantum stream cipher by the Yuen 2000 protocol: Design and experiment by an intensity-modulation scheme

Osamu Hirota, Masaki Sohma, Masaru Fuse +1 more

We investigate the Yuen 2000 (so-called Y-00)-protocol, which can realize a randomized stream cipher with high bit rate (Gbit/s) for long distances (several hundreds km). The randomized stream cipher with randomization by quantum noise based on the Y-00 protocol is called a quantum stream cipher in this paper, and it may have security against known plaintext attacks which has no analog with any conventional symmetric key ciphers. We present a simple cryptanalysis based on an attacker's heterodyne measurement and a quantum unambiguous measurement to make clear the strength of the Y-00 protocol in real communication. In addition, we give a design for the implementation of an intensity-modulation scheme and report an experimental demonstration of $1\phantom{\rule{0.3em}{0ex}}\mathrm{Gbit}∕\mathrm{s}$ quantum stream cipher through a $20\text{\ensuremath{-}}\mathrm{km}$-long transmission line.

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Progress in Y-00 physical cipher for Giga bit/sec optical data communications (intensity modulation method)

Osamu Hirota, Fumio Futami

To guarantee a security of Cloud Computing System is urgent problem. Although there are several threats in a security problem, the most serious problem is cyber attack against an optical fiber transmission among data centers. In such a network, an encryption scheme on Layer 1(physical layer) with an ultimately strong security, a small delay, and a very high speed should be employed, because a basic optical link is operated at 10 Gbit/sec/wavelength. We have developed a quantum noise randomied stream cipher so called Yuen- 2000 encryption scheme (Y-00) during a decade. This type of cipher is a completely new type random cipher in which ciphertext for a legitimate receiver and eavesdropper are different. This is a condition to break the Shannon limit in theory of cryptography. In addition, this scheme has a good balance on a security, a speed and a cost performance. To realize such an encryption, several modulation methods are candidates such as phase-modulation, intensity-modulation, quadrature amplitude modulation, and so on. Northwestern university group demonstrated a phase modulation system (α=η) in 2003. In 2005, we reported a demonstration of 1 Gbit/sec system based on intensity modulation scheme(ISK-Y00), and gave a design method for quadratic amplitude modulation (QAM-Y00) in 2005 and 2010. An intensity modulation scheme promises a real application to a secure fiber communication of current data centers. This paper presents a progress in quantum noise randomized stream cipher based on ISK-Y00, integrating our theoretical and experimental achievements in the past and recent 100 Gbit/sec(10Gbit/sec × 10 wavelengths) experiment.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Oct 8, 2014•0 citations

Security analysis of a QAM modulated quantum noise stream cipher under a correlation attack

Mingrui Zhang, Yajie Li, Haokun Song +3 more

Quantum noise stream cipher where encrypted signals are masked by quantum noise and ASE noise provides a physical layer of security. It requires the transmitter and the receiver to share a stream cipher that is generated from a PRNG. Yet a correlation attack threatens its security due to the mathematical properties of PRNG. This paper discusses the security of QNSC system under correlation attacks. Our experiment results find that the security of the whole system depends on the cycle to refresh the seed key and the correlation between the incepted running key, original running key, and seed key. Furthermore, it is important to provide security for the QNSC system by maintaining low optical power. Besides, this new analytical method provides quantitative security analysis for a QNSC system under a correlation attack.

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Progress in Y-00 physical cipher for Giga bit/sec optical data communications -Intensity modulation method

Osamu Hirota, Fumio Futami

To guarantee a security of Cloud Computing System is urgent problem. Although there are several threats in a security problem, the most serious problem is cyber attack against an optical fiber transmission among data centers. In such a network, an encryption scheme on Layer 1(physical layer) with an ultimately strong security, a small delay, and a very high speed should be employed, because a basic optical link is operated at 10 Gbit/sec/wavelength. We have developed a quantum noise randomied stream cipher so called Yuen- 2000 encryption scheme (Y-00) during a decade. This type of cipher is a completely new type random cipher in which ciphertext for a legitimate receiver and eavesdropper are different. This is a condition to break the Shannon limit in theory of cryptography. In addition, this scheme has a good balance on a security, a speed and a cost performance. To realize such an encryption, several modulation methods are candidates such as phase-modulation, intensity-modulation, quadrature amplitude modulation, and so on. Northwestern university group demonstrated a phase modulation system (α=η) in 2003. In 2005, we reported a demonstration of 1 Gbit/sec system based on intensity modulation scheme(ISK-Y00), and gave a design method for quadratic amplitude modulation (QAM-Y00) in 2005 and 2010. An intensity modulation scheme promises a real application to a secure fiber communication of current data centers. This paper presents a progress in quantum noise randomized stream cipher based on ISK-Y00, integrating our theoretical and experimental achievements in the past and recent 100 Gbit/sec(10Gbit/sec × 10 wavelengths) experiment.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Jan 1, 2014•0 citations
In any communication system, all data including encrypted data by the mathematical cipher are transmitted under the strict rule of the interface frame. Attacker can easily acquire the whole data the same as the data of legitimate users including the address, routing information and so on from the transmission line by tapping.
This is very risky, especially for the secret sharing data center operations. So to hide the whole data in the transmission line is very attractive to ensure the high security level. This can be realized by Y-00 type random cipher that the ciphertext of simple mathematical cipher by PRNG is randomized by quantum noise and it gives a masking effect against the attacker's security analysis. This paper clarifies quantitative properties on the masking effect in the random cipher by Y-00 protocol, and shows the fact that a scheme by the intensity modulation may provide the greatest masking effect, even if the attacker employs the universal heterodyne receiver.
In any communication system, all data including encrypted data by the mathematical cipher are transmitted under the strict rule of the interface frame. Attacker can easily acquire the whole data the same as the data of legitimate users including the address, routing information and so on from the transmission line by tapping. This is very risky, especially for the secret sharing data center operations. So to hide the whole data in the transmission line is very attractive to ensure the high security level. This can be realized by Y-00 type random cipher that the ciphertext of simple mathematical cipher by PRNG is randomized by quantum noise and it gives a masking effect against the attacker's security analysis. This paper clarifies quantitative properties on the masking effect in the random cipher by Y-00 protocol, and shows the fact that a scheme by the intensity modulation may provide the greatest masking effect, even if the attacker employs the universal heterodyne receiver.
The Internet plays an essential role in modern societies and in the amount of sensitive data transported over the optical networks that shows its' importance has increased drastically. Therefore, it is critical to develop data protection schemes for optical fiber communications to provide user security. The Y-00 quantum-noise randomized stream cipher that employs extremely high-order modulation and restricts an attacker's interception of ciphertext is a practical candidate for providing data protection. In this article, we introduce the operation principle of the Y-00 cipher with respect to data encryption and decryption. The Y-00 cipher combines the mathematical encryption of multi-level signaling and physical randomness, and provides a high level of security to the physical layer of optical communications and a high communication performance. We also present the noise masking phenomenon of the Y-00 cipher with intensity modulation (IM). This noise masking is generated by shot noise, i.e., quantum noise and additive noise such as amplified spontaneous emission noise. The noise masking phenomenon fails an attacker's interception of the ciphertext. The secrecy of the IM Y-00 cipher is also discussed, and an approximate analytical solution is introduced for evaluating the probability of the attackers accurately guessing the ciphertext. Finally, the secrecy of a 1,000-km transmission system is experimentally demonstrated with the Y-00 cipher transceiver at data rate of 1.5-Gb/s using the derived analytical solution to deduce the high secrecy of the entire transmission system.
We investigate the Yuen 2000 (so-called Y-00)-protocol, which can realize a randomized stream cipher with high bit rate (Gbit/s) for long distances (several hundreds km). The randomized stream cipher with randomization by quantum noise based on the Y-00 protocol is called a quantum stream cipher in this paper, and it may have security against known plaintext attacks which has no analog with any conventional symmetric key ciphers. We present a simple cryptanalysis based on an attacker's heterodyne measurement and a quantum unambiguous measurement to make clear the strength of the Y-00 protocol in real communication. In addition, we give a design for the implementation of an intensity-modulation scheme and report an experimental demonstration of 1Gbit∕s1\phantom{\rule{0.3em}{0ex}}\mathrm{Gbit}∕\mathrm{s}1Gbit∕s quantum stream cipher through a $20\text{\ensuremath{-}}\mathrm{km}$-long transmission line.
To guarantee a security of Cloud Computing System is urgent problem. Although there are several threats in a security problem, the most serious problem is cyber attack against an optical fiber transmission among data centers. In such a network, an encryption scheme on Layer 1(physical layer) with an ultimately strong security, a small delay, and a very high speed should be employed, because a basic optical link is operated at 10 Gbit/sec/wavelength. We have developed a quantum noise randomied stream cipher so called Yuen- 2000 encryption scheme (Y-00) during a decade. This type of cipher is a completely new type random cipher in which ciphertext for a legitimate receiver and eavesdropper are different. This is a condition to break the Shannon limit in theory of cryptography. In addition, this scheme has a good balance on a security, a speed and a cost performance. To realize such an encryption, several modulation methods are candidates such as phase-modulation, intensity-modulation, quadrature amplitude modulation, and so on. Northwestern university group demonstrated a phase modulation system (α=η) in 2003. In 2005, we reported a demonstration of 1 Gbit/sec system based on intensity modulation scheme(ISK-Y00), and gave a design method for quadratic amplitude modulation (QAM-Y00) in 2005 and 2010. An intensity modulation scheme promises a real application to a secure fiber communication of current data centers. This paper presents a progress in quantum noise randomized stream cipher based on ISK-Y00, integrating our theoretical and experimental achievements in the past and recent 100 Gbit/sec(10Gbit/sec × 10 wavelengths) experiment.
Quantum noise stream cipher where encrypted signals are masked by quantum noise and ASE noise provides a physical layer of security. It requires the transmitter and the receiver to share a stream cipher that is generated from a PRNG. Yet a correlation attack threatens its security due to the mathematical properties of PRNG. This paper discusses the security of QNSC system under correlation attacks. Our experiment results find that the security of the whole system depends on the cycle to refresh the seed key and the correlation between the incepted running key, original running key, and seed key. Furthermore, it is important to provide security for the QNSC system by maintaining low optical power. Besides, this new analytical method provides quantitative security analysis for a QNSC system under a correlation attack.
To guarantee a security of Cloud Computing System is urgent problem. Although there are several threats in a security problem, the most serious problem is cyber attack against an optical fiber transmission among data centers. In such a network, an encryption scheme on Layer 1(physical layer) with an ultimately strong security, a small delay, and a very high speed should be employed, because a basic optical link is operated at 10 Gbit/sec/wavelength. We have developed a quantum noise randomied stream cipher so called Yuen- 2000 encryption scheme (Y-00) during a decade. This type of cipher is a completely new type random cipher in which ciphertext for a legitimate receiver and eavesdropper are different. This is a condition to break the Shannon limit in theory of cryptography. In addition, this scheme has a good balance on a security, a speed and a cost performance. To realize such an encryption, several modulation methods are candidates such as phase-modulation, intensity-modulation, quadrature amplitude modulation, and so on. Northwestern university group demonstrated a phase modulation system (α=η) in 2003. In 2005, we reported a demonstration of 1 Gbit/sec system based on intensity modulation scheme(ISK-Y00), and gave a design method for quadratic amplitude modulation (QAM-Y00) in 2005 and 2010. An intensity modulation scheme promises a real application to a secure fiber communication of current data centers. This paper presents a progress in quantum noise randomized stream cipher based on ISK-Y00, integrating our theoretical and experimental achievements in the past and recent 100 Gbit/sec(10Gbit/sec × 10 wavelengths) experiment.