One-time Pad Encryption Research Articles

Weak blind quantum signature protocol based on entanglement swapping

In this paper, we put forward a weak blind quantum signature scheme based on quantum entanglement swapping of Bell states. Different from the existing quantum signature schemes, our scheme can offer two-step verification security services to ensure the validity of the verification. In order to guarantee the unconditional security of the scheme, the quantum key distribution protocol and one-time pad encryption algorithm are employed in our scheme. Besides, the entanglement swapping of Bell states mechanism enhances the security of verification criteria. The proposed scheme has the properties of nonforgeability, nonrepudiation, blindness, and traceability.

Evaluation of anonymity and confidentiality protocols using theorem proving

Anonymity and confidentiality protocols constitute crucial parts in many network applications as they ensure anonymous communications between entities in a network or provide security in insecure communication channels. Evaluating the properties of these protocols is therefore of paramount importance, especially in the case of safety-critical applications. However, traditional analysis techniques, like simulation, cannot ascertain accurate analysis in this domain. We propose to overcome this limitation by conducting an information leakage analysis of anonymity and cryptographic protocols within the trusted kernel of a higher-order-logic theorem prover. For this purpose, we first introduce two novel measures of information leakage, namely the information leakage degree and the conditional information leakage degree and then present a higher-order-logic formalization of information measures and the underlying required theories of measure, probability and information. For illustration purposes, we use the proposed framework to evaluate the security properties of the one-time pad encryption system as well as the properties of an anonymity-based single MIX. We show how this formal analysis allowed us to find a counter-example for a theorem that was reported in the literature to describe the leakage properties of this single MIX.

Quantum-Locked Key Distribution at Nearly the Classical Capacity Rate

Quantum data locking is a protocol that allows for a small secret key to (un)lock an exponentially larger amount of information, hence yielding the strongest violation of the classical one-time pad encryption in the quantum setting. This violation mirrors a large gap existing between two security criteria for quantum cryptography quantified by two entropic quantities: the Holevo information and the accessible information. We show that the latter becomes a sensible security criterion if an upper bound on the coherence time of the eavesdropper's quantum memory is known. Under this condition, we introduce a protocol for secret key generation through a memoryless qudit channel. For channels with enough symmetry, such as the d-dimensional erasure and depolarizing channels, this protocol allows secret key generation at an asymptotic rate as high as the classical capacity minus one bit.

Robust quantum data locking from phase modulation

Quantum data locking is a unique quantum phenomenon that allows a relatively short key to (un)lock an arbitrarily long message encoded in a quantum state, in such a way that an eavesdropper who measures the state but does not know the key has essentially no information about the encrypted message. The application of quantum data locking in cryptography would allow one to overcome the limitations of the one-time pad encryption, which requires the key to have the same length as the message. However, it is known that the strength of quantum data locking is also its Achilles heel, as the leakage of a few bits of the key or the message may in principle allow the eavesdropper to unlock a disproportionate amount of information. In this paper we show that there exist quantum data locking schemes that can be made robust against information leakage by increasing the length of the shared key by a proportionate amount. This implies that a constant size key can still encrypt an arbitrarily long message as long as a fraction of it remains secret to the eavesdropper. Moreover, we greatly simplify the structure of the protocol by proving that phase modulation suffices to generate strong locking schemes, paving the way to optical experimental realizations. Also, we show that successful data locking protocols can be constructed using random codewords, which very well could be helpful in discovering random codes for data locking over noisy quantum channels.

Three-step semiquantum secure direct communication protocol

Quantum secure direct communication is the direct communication of secret messages without need for establishing a shared secret key first. In the existing schemes, quantum secure direct communication is possible only when both parties are quantum. In this paper, we construct a three-step semiquantum secure direct communication (SQSDC) protocol based on single photon sources in which the sender Alice is classical. In a semiquantum protocol, a person is termed classical if he (she) can measure, prepare and send quantum states only with the fixed orthogonal quantum basis{|0>,|1>}. The security of the proposed SQSDC protocol is guaranteed by the complete robustness of semiquantum key distribution protocols and the unconditional security of classical one-time pad encryption. Therefore, the proposed SQSDC protocol is also completely robust. Complete robustness indicates that nonzero information acquired by an eavesdropper Eve on the secret message implies the nonzero probability that the legitimate participants can find errors on the bits tested by this protocol. In the proposed protocol, we suggest a method to check Eves disturbing in the doves returning phase such that Alice does not need to announce publicly any position or their coded bits value after the photons transmission is completed. Moreover, the proposed SQSDC protocol can be implemented with the existing techniques. Compared with many quantum secure direct communication protocols, the proposed SQSDC protocol has two merits: firstly the sender only needs classical capabilities; secondly to check Eves disturbing after the transmission of quantum states, no additional classical information is needed.

An Innovative Approach for Implementation of One-Time Pads

This paper presents a different way for implementation of onetime pad. The one-time pad are known as the mother of all encryption schemes, since it is known to be informationtheoretically secure in contrast to other encryption schemes used in practice, which are at most computationally secure. Our proposed way will make encryption impossible to crack if used correctly. We are implementing one-time pad encryption technique using both block cipher and one-way hash. In this proposed method each bit or character from the plaintext is encrypted by a modular addition with a bit or character from a secret random key of the same length as the plaintext, resulting in a cipher text. If the key is truly random and at least as long as the plaintext also never reused in whole or part and kept secret the cipher text will be impossible to decrypt or break without knowing the key.

Random Bit Generator Using Delayed Self-Difference of Filtered Amplified Spontaneous Emission

We propose a scheme for random bit generation with filtered amplified spontaneous emission (ASE). Using the filtered ASE, we can get larger signal fluctuations than when using directly detected ASE with a photodetector. Utilizing the delayed self-difference technique to improve the symmetry of filtered ASE, we experimentally achieve real-time 2.5-Gbit/s random sequence generation, which matches with the speeds of fiber communication for one-time pad encryption. Experimental results show that the generated random sequences can pass NIST tests as long as the delay time is beyond a threshold value, which is called the minimum delay time (MDT). Further simulation results indicate that there is a certain relationship between the MDT and bandwidth of the ASE signal.

A Novel Privacy Preserving Location-Based Service Protocol With Secret Circular Shift for $k$-NN Search

Location-based service (LBS) is booming up in recent years with the rapid growth of mobile devices and the emerging of cloud computing paradigm. Among the challenges to establish LBS, the user privacy issue becomes the most important concern. A successful privacy-preserving LBS must be secure and provide accurate query [e.g., -nearest neighbor (NN)] results. In this work, we propose a private circular query protocol (PCQP) to deal with the privacy and the accuracy issues of privacy-preserving LBS. The protocol consists of a space filling curve and a public-key homomorphic cryptosystem. First, we connect the points of interest (POIs) on a map to form a circular structure with the aid of a Moore curve. And then the homomorphism of Paillier cryptosystem is used to perform secret circular shifts of POI-related information (POI-info), stored on the server side. Since the POI-info after shifting and the amount of shifts are encrypted, LBS providers (e.g., servers) have no knowledge about the user's location during the query process. The protocol can resist correlation attack and support a multiuser scenario as long as the predescribed secret circular shift is performed before each query; in other words, the robustness of the proposed protocol is the same as that of a one-time pad encryption scheme. As a result, the security level of the proposed protocol is close to perfect secrecy without the aid of a trusted third party and simulation results show that the k-NN query accuracy rate of the proposed protocol is higher than 90% even when is large.

One-Time Pad as a nonlinear dynamical system

The One-Time Pad (OTP) is the only known unbreakable cipher, proved mathematically by Shannon in 1949. In spite of several practical drawbacks of using the OTP, it continues to be used in quantum cryptography, DNA cryptography and even in classical cryptography when the highest form of security is desired (other popular algorithms like RSA, ECC, AES are not even proven to be computationally secure). In this work, we prove that the OTP encryption and decryption is equivalent to finding the initial condition on a pair of binary maps (Bernoulli shift). The binary map belongs to a family of 1D nonlinear chaotic and ergodic dynamical systems known as Generalized Luröth Series (GLS). Having established these interesting connections, we construct other perfect secrecy systems on the GLS that are equivalent to the One-Time Pad, generalizing for larger alphabets. We further show that OTP encryption is related to Randomized Arithmetic Coding – a scheme for joint compression and encryption.

Quantum key distribution with delayed privacy amplification and its application to the security proof of a two-way deterministic protocol

Privacy amplification (PA) is an essential post-processing step in quantum key distribution (QKD) for removing any information an eavesdropper may have on the final secret key. In this paper, we consider delaying PA of the final key after its use in one-time pad encryption and prove its security. We prove that the security and the key generation rate are not affected by delaying PA. Delaying PA has two applications: it serves as a tool for significantly simplifying the security proof of QKD with a two-way quantum channel, and also it is useful in QKD networks with trusted relays. To illustrate the power of the delayed PA idea, we use it to prove the security of a qubit-based two-way deterministic QKD protocol which uses four states and four encoding operations.

Nanoscale Shuffling in a Template-Assisted Self-Assembly of Binary Colloidal Particles

We have fabricated a square lattice array of sub-micrometer fluorescent (red and green) polystyrene particles. The particles were each embedded into small pits fabricated on a silicon substrate by electron beam lithography, through the drying process of an aqueous suspension containing equal amounts of the two species. We indexed 0 and 1 for each red and green particle, respectively, and then obtained a one-dimensional bit sequence by the successive reading of the indices in a predetermined manner. We evaluated the randomness of the bit sequence by using the improved FIPS 140-2 statistical test suite. Consequently, we found that the bit sequences do not have any non-randomness. The particle array was obtained by a very simple process, i.e., the drying of a suspension, but the particle distribution pattern was definitely unpredictable and irreproducible, and the number of possible patterns was tremendously large. The signal--i.e., the color of the particle--does not deteriorate within a practical timescale under various conditions, such as in an electric field, in a magnetic field, in air or water, on a solid matrix, and so on, which means that a small tip with the particle pattern can be installed in miscellaneous object, including electronic products, plastic credit cards, currency bills, and so on. Therefore, this particle array is applicable to a nanoscale identification tag or a one-time pad encryption tip.

Quantum proxy signature scheme with public verifiability

In recent years, with the development of quantum cryptography, quantum signature has also made great achievement. However, the effectiveness of all the quantum signature schemes reported in the literature can only be verified by a designated person. Therefore, its wide applications are limited. For solving this problem, a new quantum proxy signature scheme using EPR quantum entanglement state and unitary transformation to generate proxy signature is presented. Proxy signer announces his public key when he generates the final signature. According to the property of unitary transformation and quantum one-way function, everyone can verify whether the signature is effective or not by the public key. So the quantum proxy signature scheme in our paper can be public verified. The quantum key distribution and one-time pad encryption algorithm guarantee the unconditional security of this scheme. Analysis results show that this new scheme satisfies strong non-counterfeit and strong non-disavowal. quantum cryptography, proxy signature, quantum one-way function, public verifiably

Formal Method of Encryption Using 9’S Complement

In this paper we show how implemented one time security encryption scheme is more lucid, effective. However it is more complex in nature of attacker view. The one-time pad encryption scheme itself is mathematically unbreakable. (See Claude Shannon's Communication Theory of Secrecy Systems). Therefore, the attacker will focus on breaking the key instead of the cipher text. Random key stream can be used to create lifetime supply of keys for one time pads. Here we provided the practical approach that you can use to set up your own one-time pad encryption. Permutation techniques can be used in conjunction with other technique includes substitution, encryption function etc. for effective performance. The goal of this paper to show how the one-time pad encryption technique can be achieved including complement approach technique.

A novel cellular automata based technique for visual multimedia content encryption

This paper proposes a new method for visual multimedia content encryption using Cellular Automata (CA). The encryption scheme is based on the application of an attribute of the CLF XOR filter, according to which the original content of a cellular neighborhood can be reconstructed following a predetermined number of repeated applications of the filter. The encryption is achieved using a key image of the same dimensions as the image being encrypted. This technique is accompanied by the one-time pad (OTP) encryption method, rendering the proposed method reasonably powerful, given the very large number of resultant potential security keys. The method presented here makes encryption possible in cases where there is more than one image with the use of just one key image. A further significant characteristic of the proposed method is that it demonstrates how techniques from the field of image retrieval can be used in the field of image encryption. The proposed method is further strengthened by the fact that the resulting encrypted image for a given key image is different each time. The encryption result depends on the structure of an artificial image produced by the superposition of four 1-D CA time–space diagrams as well as from a CA random number generator. A semi-blind source separation algorithm is used to decrypt the encrypted image. The result of the decryption is a lossless representation of the encrypted image. Simulation results demonstrate the effectiveness of the proposed encryption method. The proposed method is implemented in C# and is available online through the img(Rummager) application.

Implemented Encryption Scheme (One Time Pad ) using 9’S Complement

In this articles we show how implemented one time security encryption scheme is more lucid , effective , However it is more complex in nature of attacker view. The one-time pad encryption scheme itself is mathematically unbreakable. (see Claude Shannon's Communication Theory of Secrecy Systems). Therefore, the attacker will focus on breaking the key instead of the cipher text. Random key stream can be used to create lifetime supply of keys for one time pads. Here we provided the practical approach that you can use to set up your own one-time pad encryption. Permutation techniques can be used in conjunction with other technique includes substitution, encryption function etc. for effective performance. The goal of this article to show how the one-time pad encryption technique can be achieved including complement approach technique. Keywords: Cryptography, One-time pad, Encryption, Key -Enhancement, Network Security, Computer Security.

An Innovative Approach to Enhance the Security of Data Encryption Scheme

In this paper, we proposed a new scheme to enhance the security of data Encryption scheme. With cascading of data encryption standard in three times, we become able to counter the famous meet in middle attack in double and triple data encryption standard. We show how the random key stream can be used to create lifetime supply of keys for one time pads. Here we provided the practical approach that we can use to set up our own one-time pad encryption. For simplicity let's study how randomized key can be achieved. Random key generation can simply be obtained via use of permutation. Permutation technique can be used in conjunction with other technique includes substitution, encryption function etc. for effective performance. The goal of this article to show how the one-time pad encryption technique can be achieved by the suitable combination of these techniques.

Effective algorithm to encrypt information based on self-assembly of DNA tiles

We present an error-tolerance scheme to encrypt information in DNA structures based on a one-time-pad (OTP) cryptosystem that provides theoretically unbreakable security. The problem of the DNA-based OTP encryption is the loss of synchronization between the message and the encryption key due to the DNA property of accepting mismatched base pairs. We propose a new implementation idea of encrypting algorithm with the fourfold fault tolerance against mismatches than the ordinary DNA XOR operation. Although there are several problems to be solved toward the practical use at this moment, it is expected that the molecular computation using DNA tiles will enlarge the application possibility of the OTP cryptosystem.

Field test of a practical secure communication network with decoy-state quantum cryptography

We present a secure network communication system that operated with decoy-state quantum cryptography in a real-world application scenario. The full key exchange and application protocols were performed in real time among three nodes, in which two adjacent nodes were connected by approximate 20 km of commercial telecom optical fiber. The generated quantum keys were immediately employed and demonstrated for communication applications, including unbreakable real-time voice telephone between any two of the three communication nodes, or a broadcast from one node to the other two nodes by using one-time pad encryption.

Demonstration of an All-Optical OCDMA Encryption and Decryption System With Variable Two-Code Keying

We demonstrate the first all-optical optical code-division multiple-access (OCDMA) encryption and decryption system with variable two-code keying. The nonlinear optical loop mirror (NOLM)-based exclusive or (xor) employed in encryption utilizes the shortest length silica-based nonlinear fiber element to date, enabling a compact architecture. Fiber Bragg grating arrays create wavelength-hopping time-spreading OCDMA codes from broadband pulses at output ports of the xor resulting in variable two-code keying, a code-switching modulation format characterized by a random alternation in bit representation and immunity to differential analysis unlike fixed two-code keying. The terahertz optical asymmetric demultiplexer employed in decryption shows mutual compatibility of nonlinear fiber-based and semiconductor optical amplifier-based NOLM configurations. Our architecture can potentially perform one-time pad encryption and decryption for unconditional security.

A security approach for off-chip memory in embedded microprocessor systems

This paper describes a complete off-chip memory security solution for embedded systems. Our security core is based on a one-time pad (OTP) encryption circuit and a CRC-based integrity checking module. These modules safeguard external memory used by embedded processors against a series of well-known attacks, including replay attacks, spoofing attacks and relocation attacks. Our implementation limits on-chip memory space overhead to less than 33% versus memory used by a standard microprocessor and reduces memory latency achieved by previous approaches by at least half. The performance loss for software execution with our solution is only 10% compared with a non-protected implementation. An FPGA prototype of our security core has been completed to validate our findings.