In this paper, an approach referred to as IoTsecM is proposed. This proposal is a UML/SysML extension for security requirements modeling within the analysis stage in a waterfall development life cycle in a Model-Based Systems Engineering Approach. IoTsecM allows the security requirements representation in two very well-known modeling languages, UML and SysML. With the utilization of this extension, IoT developers can consider the security requirements from the analysis stage in the design process of IoT systems. IoTsecM allows IoT systems to be designed considering possible threats and the corresponding security requirements analysis. The applicability of IoTsecM is demonstrated through applying it to analyze and represent the security requirements in an IoT real-life system in the context of collaborative autonomous vehicles in smart cities. In this use case, IoTsecM was able to represent the security requirements identified within the system architecture elements, in which all countermeasures identified were depicted using the proposed IoTsecM profile.

In recent years, there has been a notable amount of research on developing cryptographic schemes that are secure against both quantum and classical computers. In 2016, the National Institute of Standards and Technology (NIST) initiated a process to solicit, evaluate, and standardize one or more quantum-resistant public key cryptographic schemes. This process originated because quantum computers can exploit quantum mechanical phenomena and solve mathematical problems that are difficult or intractable for classical computers. This kind of mathematical problem is the basis of secure public key cryptography. As a consequence, in a near future quantum computers will be able to break many of the public key schemes currently in use. However, the challenge is especially acute for devices with different architectures. They might not be well equipped to run the new standards and interoperate with existing communication protocols and networks. In this work, we analyze the performance of postquantum schemes in the transport layer security (TLS) protocol considering x86 as the server architecture and x86/ARM architectures as clients. All of them lack cloud computing or virtualized environments. Our analysis considers integrating the implementation of two cryptographic schemes that were successful in the second round of the postquantum standardization process, namely, Dilithium and New Hope. The performance of postquantum schemes in the TLS protocol is statistically analyzed in x86 and ARM architectures, giving the relationships, the effects and the survival of the analysis.

Nowadays, technological advances provide people with more facilities and luxuries in life. Medicine is no exception; for example, different wireless sensors can be used to monitor patients’ state of health. These sensors are used in the so-called Wireless Body Area Networks (WBAN), to improve the efficiency of doctor-patient activities at any time, in any body area, and anywhere. However, health data contains sensitive information that becomes a critical issue requiring special attention when transmitted within a WBAN. In other words, WBAN must be protected from malicious devices that intercept, alter or access without authorization or even deny the health information being transmitted. In this article, we present the design of a new cryptographic protocol that guarantees three security services, authentication, confidentiality, and integrity by securing sensitive information communication through a WBAN. We also consider a keyless sensors authentication method to distinguish whether or not the devices are placed on the same individual’s body. A formal analysis of the protocol is carried out using cryptographic protocol verification tools to guarantee its correct construction and that it provides appropriate security.

A ransomware is a kind of malware used for digital extortion purposes, where victims must make a payment with acryptocurrency in exchange of information or compromised systems. This article presents a method to analyze thedynamic of Bitcoin transactions related to ransomware, through the representation of the blockchain as a directednetwork, and the measurement of the corresponding parameters, as well as statistical analysis and a transaction tracking.

Peer-to-peer (P2P) networks are distributed systems with a communication model in which no central authority governs the behavior of individual peers. These networks currently account for a considerable percentage of all bandwidth worldwide. However, this communication model also has a clear disadvantage: it has a multitude of vulnerabilities and security threats. The nature of the P2P philosophy itself means that there is no centralized server responsible for uploading, storing, and verifying the authenticity of the shared files and packets. A direct consequence of this is that P2P networks are a good choice for hackers for the spread of malicious software or malware in general since there is no mechanism to control what content is shared. In this paper, we present a mathematical model for P2P networks to study the effect of two different attacks on these systems, namely, malware and denial of service. To analyze the behavior of the cyber attacks and identify important weaknesses, we develop different Markov chains that reflect the main dynamics of the system and the attacks. Specifically, our model considers the case in which a certain number of nodes are infected with a cyber worm that is spread throughout the network as the file is shared among peers. This allows observation of the final number of infected peers when an initial number (we evaluate the system for from 1 to 14 initial nodes) of malicious nodes infect the system. For the DoS attack, our model considers the portion of peers that are unable to communicate and the average attack duration to study the performance degradation of such an attack. A two-pronged approach was used to study the impact of the attacks on P2P networks; the first focused only on the P2P network, and the second focused on the attacks and the network.

In blockchain-based systems the privacy use to be a concern and the key management is not widely revisited. In this work we present a threshold blind signature scheme designed on the modified version of the Paillier cryptosystem presented by Yi et al. Our scheme guarantees four main characteristics of interest: Independence meaning that our scheme could be applied to any blockchain-based transaction system. Secure key storage which improves the key management security under the idea that one single key is always an easier target for an attack or a failure, in such way that our threshold scheme recovers the signature instead of the private key, therefore nobody can access to the private key. Anonymity, which is one of the best-evaluated features on online transactions; and independence from mixers or trusted third parties, which most of the time they are used to reach anonymity but there are inherent risks to take in count about having a transaction in a third party. We achieve such a four characteristics without increase costs in comparison with related work.