Biblio

Filters: Author is OTSUKA, Akira  [Clear All Filters]
2020-09-28
Mitani, Tatsuo, OTSUKA, Akira.  2019.  Traceability in Permissioned Blockchain. 2019 IEEE International Conference on Blockchain (Blockchain). :286–293.
In this paper, we propose the traceability of assets in a permissioned blockchain connected with a permissionless blockchain. We make traceability of assets in the permissioned blockchain be defined and be expressed as a hidden Markov model. There exists no dishonest increase and decrease of assets in this model. The condition is called balance. As we encrypt this model with fully homomorphic encryption and apply the zero knowledge proof of plaintext knowledge, we show that the trace-ability and balance of the permissioned blockchain are able to be proved in zero knowledge to the permissionless blockchain with concealing the asset allocation of the permissioned blockchain.
2020-01-28
KADOGUCHI, Masashi, HAYASHI, Shota, HASHIMOTO, Masaki, OTSUKA, Akira.  2019.  Exploring the Dark Web for Cyber Threat Intelligence Using Machine Leaning. 2019 IEEE International Conference on Intelligence and Security Informatics (ISI). :200–202.

In recent years, cyber attack techniques are increasingly sophisticated, and blocking the attack is more and more difficult, even if a kind of counter measure or another is taken. In order for a successful handling of this situation, it is crucial to have a prediction of cyber attacks, appropriate precautions, and effective utilization of cyber intelligence that enables these actions. Malicious hackers share various kinds of information through particular communities such as the dark web, indicating that a great deal of intelligence exists in cyberspace. This paper focuses on forums on the dark web and proposes an approach to extract forums which include important information or intelligence from huge amounts of forums and identify traits of each forum using methodologies such as machine learning, natural language processing and so on. This approach will allow us to grasp the emerging threats in cyberspace and take appropriate measures against malicious activities.