Key Recovery System Research Articles

Secure Encapsulation Schemes Using Key Recovery System in IoMT Environments.

Recently, as Internet of Things systems have been introduced to facilitate diagnosis and treatment in healthcare and medical environments, there are many issues concerning threats to these systems’ security. For instance, if a key used for encryption is lost or corrupted, then ciphertexts produced with this key cannot be decrypted any more. Hence, this paper presents two schemes for key recovery systems that can recover the lost or the corrupted keys of an Internet of Medical Things. In our proposal, when the key used for the ciphertext is needed, this key is obtained from a Key Recovery Field present in the cyphertext. Thus, the recovered key will allow decrypting the ciphertext. However, there are threats to this proposal, including the case of the Key Recovery Field being forged or altered by a malicious user and the possibility of collusion among participating entities (Medical Institution, Key Recovery Auditor, and Key Recovery Center) which can interpret the Key Recovery Field and abuse their authority to gain access to the data. To prevent these threats, two schemes are proposed. The first one enhances the security of a multi-agent key recovery system by providing the Key Recovery Field with efficient integrity and non-repudiation functions, and the second one provides a proxy re-encryption function resistant to collusion attacks against the key recovery system.

Consumers' Intentions to Adopt Blockchain-Based Personal Health Records and Data Sharing: Focus Group Study.

BackgroundAlthough researchers are giving increased attention to blockchain-based personal health records (PHRs) and data sharing, the majority of research focuses on technical design. Very little is known about health care consumers’ intentions to adopt the applications.ObjectiveThis study aims to explore the intentions and concerns of health care consumers regarding the adoption of blockchain-based personal health records and data sharing.MethodsThree focus groups were conducted, in which 26 participants were shown a prototype of a user interface for a self-sovereign blockchain-based PHR system (ie, a system in which the individual owns, has custody of, and controls access to their personal health information) to be used for privacy and secure health data sharing. A microinterlocutor analysis of focus group transcriptions was performed to show a descriptive overview of participant responses. NVivo 12.0 was used to code the categories of the responses.ResultsParticipants did not exhibit a substantial increase in their willingness to become owners of health data and share the data with third parties after the blockchain solution was introduced. Participants were concerned about the risks of losing private keys, the resulting difficulty in accessing care, and the irrevocability of data access on blockchain. They did, however, favor a blockchain-based PHR that incorporates a private key recovery system and offers a health wallet hosted by government or other positively perceived organizations. They were more inclined to share data via blockchain if the third party used the data for collective good and offered participants nonmonetary forms of compensation and if the access could be revoked from the third party.ConclusionsHealth care consumers were not strongly inclined to adopt blockchain-based PHRs and health data sharing. However, their intentions may increase when the concerns and recommendations demonstrated in this study are considered in application design.

A Key Recovery System Based on Password-protected Secret Sharing in a Permissioned Blockchain

A Key Recovery System Based on Password-protected Secret Sharing in a Permissioned Blockchain

Structural cryptanalysis of McEliece schemes with compact keys

A very popular trend in code-based cryptography is to decrease the public-key size by focusing on subclasses of alternant/Goppa codes which admit a very compact public matrix, typically quasi-cyclic ($$\mathrm{QC}$$QC), quasi-dyadic ($$\mathrm{QD}$$QD), or quasi-monoidic ($$\mathrm{QM}$$QM) matrices. We show that the very same reason which allows to construct a compact public-key makes the key-recovery problem intrinsically much easier. The gain on the public-key size induces an important security drop, which is as large as the compression factor $$p$$p on the public-key. The fundamental remark is that from the $$k\times n$$k×n public generator matrix of a compact McEliece, one can construct a $$k/p \times n/p$$k/p×n/p generator matrix which is--from an attacker point of view--as good as the initial public-key. We call this new smaller code the folded code. Any key-recovery attack can be deployed equivalently on this smaller generator matrix. To mount the key-recovery in practice, we also improve the algebraic technique of Faugere, Otmani, Perret and Tillich (FOPT). In particular, we introduce new algebraic equations allowing to include codes defined over any prime field in the scope of our attack. We describe a so-called structural elimination which is a new algebraic manipulation which simplifies the key-recovery system. As a proof of concept, we report successful attacks on many cryptographic parameters available in the literature. All the parameters of CFS-signatures based on $$\mathrm{QD}$$QD/$$\mathrm{QM}$$QM codes that have been proposed can be broken by this approach. In most cases, our attack takes few seconds (the hardest case requires less than 2 h). In the encryption case, the algebraic systems are harder to solve in practice. Still, our attack succeeds against several cryptographic challenges proposed for $$\mathrm{QD}$$QD and $$\mathrm{QM}$$QM encryption schemes. We mention that some parameters that have been proposed in the literature remain out of reach of the methods given here. However, regardless of the key-recovery attack used against the folded code, there is an inherent weakness arising from Goppa codes with $$\mathrm{QM}$$QM or $$\mathrm{QD}$$QD symmetries. Indeed, the security of such schemes is not relying on the bigger compact public matrix but on the small folded code which can be efficiently broken in practice with an algebraic attack for a large set of parameters.

Key recovery for the commercial environment

We propose an efficient, scalable, certification-based key recovery system that is a hybrid of the key escrow and key encapsulation techniques. The proposed key recovery system is highly flexible and can be employed in a variety of policy environments. It possesses the properties required for commercial key recovery systems. We demonstrate the claims by comparing the computation and communication requirements for our proposal with a key recovery solution implemented by IBM.

Specification and analysis of n-way key recovery system by Extended Cryptographic Timed Petri Net

When a receiver of a ciphertext message cannot decrypt the message due to the fact that he has lost his private-key, the private-key of the receiver and session-key of the message need to be recovered. In this paper, we design a new n-way Key Recovery System ( n-KRS) that is characterized by key encapsulation approach, n-way key recovery, secret designation of key recovery agents, fork and join of session-key with random keys, recovery request by a new key pair, certificate attaching scheme, component-based software engineering, and conformance to international standards. n-KRS is specified and analyzed by Extended Cryptographic Timed Petri Net (ECTPN) model that is a new formal and graphical specification model for cryptographic protocols. Recoverability, performance characteristics of n-KRS are evaluated by means of reachability graph of ECTPN. A prototype of n-KRS is developed and evaluated by means of CC 2.0 based information security system evaluation scheme.

Hybrid Key Escrow: A New Paradigm ,

A new paradigm for the design of key recovery systems called hybrid key escrow will be presented. It will be shown that such a design can guard the privacy of system users and at the same time enable authorized key recovery. The system will be analyzed against the three fundamental properties of any robust key recovery system: compliance, enforceability and traceability.

Key Recovery Functional Model

This document describes a model for key recovery. The means by which plaintext may be recovered or reconstructed from recovered key(s) is not addressed in the key recovery model. The key recovery model is a generalized model that encompasses a wide variety of key recovery systems, including both key backup and encapsulated key recovery information techniques. The key recovery model is a functional model. That is, the components of the model are functional components not system components.

Organization Considerations for Retrieval of Stored Data via Key Recovery Methods

The purpose of this document is to identify technical and procedural issues that need to be considered when selecting and deploying key recovery systems to enable emergency recovery of data that is stored or archived in encrypted form. Emergency recovery of encrypted data is necessary in the event that the decryption keys are unavailable through normal key management mechanisms. In many cases, the need to support emergency recovery of encrypted data is vital to ongoing operations and jurisdictional policy compliance. A disaster recovery plan may also give consideration to an ability to recover many data keys by using a single key recovery request.

A Common Key Recovery Block Format: Promoting Interoperability Between Dissimilar Key Recovery Mechanisms

When cryptographic products that employ different key recovery mechanisms need to interoperate with one another, one of the major obstacles is the inability of the decryptor product to recognize, and optionally validate, the key recovery information generated by the encryptor product. In this paper, a common Key Recovery Block (KRB) format is being proposed to facilitate interoperability between heterogeneous key recovery systems. The KRB serves as a container for mechanism-specific key recovery information, and supports techniques to identify and optionally validate the contained key recovery information. This specification provides an extensible set of KRB validation techniques - however, it makes no attempt to set a preference for one technique over the others. The choice of validation technique(s) used is determined by the policies (with respect to the use of cryptography and key recovery) that apply to the encryptor and decryptor products. It may be noted that the KRB format specification is independent of the encryption algorithm used to protect the confidentiality of the data, and independent of the communication or storage protocol used to carry the encrypted data. It should also be recognized that the KRB format proposed in this paper is of limited scope. It assumes that the key recovery information can be made available to interested parties along with the encrypted data. There are a number of open issues regarding the techniques that allow key recovery information to be associated with encrypted data (whether the key recovery information and the encrypted data are transmitted over the same channel or separate channels) — these issues are beyond the scope of this proposal.

Global Interoperability for Key Recovery

This document describes techniques for implementing key recovery. The document then addresses interoperability between encryptors and decryptors using the key encapsulation method of key recovery. The Common Key Recovery Block is presented as a cornerstone for interoperability. The interoperability is summarized in an interoperability matrix for key recovery systems.

In search of multiple domain key recovery

Key recovery systems suitable for application among multiple domains, such as those operating within international communication networks, are investigated. A general framework for analysis of key recovery systems is introduced and a set of parameter

Two-phase cryptographic key recovery system

A two-phase method of key recovery which will be referred to as Secure Key Recovery (SKR) is presented. The proposed key recovery system permits a portion of the key recovery information to be generated once and then used for multiple encrypted data communications sessions and encrypted file applications. In particular, the portion of the key recovery information that is generated just once is the only portion that requires public key encryption operations. We also describe a verification mode in which the communicating parties each produce SKR recovery information independently, without checking the other's so produced information. In this mode, if at least one side is correctly configured, all required recovery information is correctly produced. In addition, the communicating parties are free to include any optional recovery fields without causing a false invalidation of what the other parties sent. Further, we present a method of verification of key recovery information within a key recovery system, based on a variation of the three-party Diffie-Hellman key agreement procedure. Without communication with a trustee, the sender is able to encrypt recovery information in such a way that both the receiver and the respective trustee can decrypt it. This reduces the number of encryptions, and inherently validates the recovery information when the receiver decrypts it. The method allows full caching of all public key operations, thus further reducing computational overhead.

A Security Key Recovery System with Channel Quality Awareness for Smart Grid Applications

In this paper, a security key recovery system with channel quality awareness (SKRS-CQA) for smart grid applications has been proposed. Firstly, the proper key recovery agents (KRAs) are determined based on the signal-to-noise ratio (SNR) outage probability. The result of such selection includes the number and the index of selected KRAs. Then, the session key (KS) of a Smart Meter Unit (SMU) will be divided into many different pieces according to the proposed key partitioning algorithm and stored in the selected KRAs for the future key recovery if the data concentrator unit (DCU) has lost the key in unexpected events. The outage probability of SNR, the probability of KRA failure, and the probability of key compromising are also investigated. In addition, a 128-bit AES-GCM encryption algorithm is used in each KRA for authentication and identification mechanisms based on a DLMS/COSEM protocol. As shown in the system performance analysis, the system reliability, the system availability, and the data confidentiality have been improved compared with the conventional scheme. Moreover, a cooperative communication network with an amplify-and-forward relaying protocol and an optimal power allocation has been employed for improving the system reliability. From computer simulation results, it showed that the reliability of the proposed system with a cooperative scheme has been improved significantly.