Kunihiko Miyazaki

Protection (2009)

Stuart Haber, William Horne, Satoru Tezoku, Yasuo Hatano, Kunihiko Miyazaki, Danfeng Yao

In this paper we give a new signature algorithm that allows for controlled changes to the signed data. The change operations we study are removal of subdocuments (redaction), pseudonymization, and...

Under consideration for publication in Formal Aspects of Computing Verifying a Signature Architecture — A Comparative Case Study (2008)

David Basin, Hironobu Kuruma, Kunihiko Miyazaki, Kazuo Takaragi, Burkhart Wolff

Abstract. We report on a case study in applying different formal methods to model and verify an architecture for administrating digital signatures. The architecture comprises several concurrently...

Invisibly Sanitizable Digital Signature Scheme (2008)

MIYAZAKI, Kunihiko, HANAOKA, Goichiro, IMAI, Hideki

A digital signature does not allow any alteration of the document to which it is attached. Appropriate alteration of some signed documents, however, should be allowed because there are security...

PAPER Special Section on Cryptography and Information Security Digitally Signed Document Sanitizing Scheme with Disclosure Condition Control (2005)

Kunihiko Miyazaki, Mitsuru Iwamura †††b, Tsutomu Matsumoto ††††c, Ryoichi Sasaki †††††d, Hiroshi Yoshiura ††††††e, Satoru Tezuka †f

SUMMARY A digital signature does not allow any alteration of the document to which it is attached. Appropriate alteration of some signed documents, however, should be allowed because there are...

Digitally Signed Document Sanitizing Scheme with Disclosure Condition Control (2005)

MIYAZAKI, Kunihiko, IWAMURA, Mitsuru, MATSUMOTO, Tsutomu, SASAKI, Ryoichi, YOSHIURA, Hiroshi, TEZUKA, Satoru, ...

A digital signature does not allow any alteration of the document to which it is attached. Appropriate alteration of some signed documents, however, should be allowed because there are security...

A formal analysis of a digital signature architecture (2004)

Kunihiko Miyazaki, Kazuo Takaragi

Abstract We report on a case study in applying formal methods to model and validate an architecture for administrating digital signatures. We use a process-oriented modeling language to model a...

A threshold digital signature issuing scheme without secret communication (2000)

Kazuo Takaragi, Kunihiko Miyazaki, Masashi Takahashi

This paper describes an efficient (k, n) threshold digital signature scheme. In the scheme, k out of n signers cooperate to issue a signature without using trusted center. No secret communication is...

Cryptographic Approch for Workflow Systems (1970)

Yasuo Hatano, Kunihiko Miyazaki, Toshinobu Kaneko

This paper proposes encryption schemes to enforce the order of the procedure in a workflow system. In workflow systems, it is important to perform a procedure according to an order that is given by...