Nobuyuki Kanaya

PIATS: a partially sanitizable signature scheme

In e-government or e-tax payment systems, appropriate alterations on digitally signed documents are required to hide personal information, namely privacy. Standard digital signature schemes do not allow such alternations on the signed documents since there is no means to distinguish appropriate alternations from inappropriate forgeries. The sanitizable signature scheme is a possible solution for such systems in which sanitizings of partial information are possible, after a signature is signed on the original (unsanitized) document. However, in previously proposed schemes, since sanitizers are anonymous, verifiers cannot identify sanitizers, and thus dishonest sanitizings are possible. This paper proposes a new sanitizable signature scheme “PIATS” in which partial information can be sanitized. Moreover, verifiers can identify sanitizers and thus dishonest sanitizings are eliminated.

Distributed workflow management system for electronic commerce

We describe a new architecture and protocol that we have developed to meet the requirements of workflow systems that are used for electronic commerce systems among enterprises. We developed practical electronic commerce systems using XML-based workflow systems among enterprises. We found that the requirements are greatly different from traditional workflow systems in some points; such as process management, server communication protocol, history log management, data conversion, and external application calls. In this paper, we illustrate the new requirements and problems when EC systems are developed using traditional workflow architecture and protocols, then we propose our new architecture and protocol that provide solutions for these requirements and problems. In this architecture based on XML, servers have the server communication module and the external-call module. The server commutation module provides a way to make a batch request. The external-call module provides a reliable way to call business applications. We also presented a retrying algorithm that maintains consistency between a workflow engine and an external application. The logging server provides a stable and fast way to query logs by collecting events from workflow servers. Our new protocol is being proposed of WfMC (WorkFlow Management Coalition) as an extension of Wf-XML.

Model-based architecture for the Intranet

We propose a system called CEE (Cooperative Environment for Enterprise-computing) which is based on a new architecture for the Intranet. CEE works based on the enterprise model which consists of the organization, business function/process conforming to IDEFO, and resources such as persons and documents. CEE integrates enterprise information and applications based on the enterprise model and enable the following functions on the WWW. 1) CEE automatically generates and maintains WWW pages and links according to business objects in the enterprise model. 2) CEE manages documents linked to the enterprise model and provides check-in/out and version control functions. 3) CEE promotes concurrent engineering by providing notification on the creation or modification of the output document of a process to the succeeding processes. 4) CEE provides document-based project management on the IDEFO chart in addition to traditional time-based project management on the Gantt chart.

Enterprise model-based software architecture with server component integration

Many companies are seeking new information systems that support more business activities than current systems. Such a system should enable more rapid information collection and sharing, and promote increased automation. Furthermore, there is a strong technological demand for the integration of various business systems and rapid modification of business processes and rules embedded in the system. To meet this demand, we propose enterprise model-based software development and associated software architecture with integrated server components. An experimental but practical system has been developed and evaluated in projects located in various countries. This paper discusses the viability of enterprise model-based software architecture with integrated server components such as a business application system, a Web server, a workflow server, and a directory server.

Threat and countermeasure patterns for cloud computing

Recently cloud computing markets have expanded, and there are various kind of services and their providers. How-ever, Security is the primary concern of cloud users. However, service providers are unaware precisely of the types of security countermeasures required for their cloud servers. A method to define what the type security required for each operator using two security patterns are proposed. One is for typical threats and the other is for typical countermeasures. Using the two patterns with the relationship information among the functions, cloud components and stakeholders, the security coverage of the cloud and the security duties of each operator become clear.

Goal-Oriented Security Requirements Analysis for a System Used in Several Different Activities

Because an information system is used in different activities simultaneously today, we have to analyze usages of the system in the existing activities and to-be usages in an intended activity together. Especially, security aspects should be carefully analyzed because existing activities are not always secure. We propose a security requirements analysis method for resolving this problem. To take both existing and intended activities into account together, we integrate them on the basis of the unification of common actors. To explore possible attacks under integrated activities, we enumerate achievable attacks on the basis of the possible means in each actor with the help of security knowledge. To avoid or mitigate the attacks and to achieve fundamental goals, we disable some means or narrow down the means to be monitored with the help of propositional logic formulae. Through case studies on insurance business, we illustrated our idea.

Cooperative Secure Integration Process for Secure System Development

Recently, attacks on corporate websites are increasing and personal information on websites faces growing risks. Most developers are making efforts to establish secure system development processes. However, they have trouble with practice because they are busy and short of time or human resources. This paper describes a cooperative secure integration process that the authors actualize for secure system development and introduce the adapted management system.