Flexible Security Research Articles

Flexible security policies for mobile agent systems

Mobile Agent (MA) technology raises significant security concerns and requires a thorough security framework with a wide range of strategies and mechanisms for the protection of both agent platform and MA against possibly malicious reciprocal behaviour. The security infrastructure should have the ability to flexibly and dynamically offer different solutions to achieve different qualities of security service depending on application requirements. Modern inter-organisational environments require sophisticated security policies that are difficult to implement in current MA platforms where policies are often directly hard-coded into applications, thus making difficult the reconfiguration required at any policy change. The paper proposes to integrate a policy-based framework within an MA system in order to flexibly model and control agent behaviour according to application specific requirements.

Some measures of increasing rail transit riderships: Case studies

This paper is mainly concerned with how to increase rail transit ridership and how to coordinate with multimodity to optimize the entire public transportation systems. Three case cities, Montreal, Toronto and San Francisco, with metro systems are reviewed in different aspects, including urban planning, transport policy, flexible fare system, safety and security measure, special service, new technical application to improve the quality and value of its service for increasing revenues and profit, comtributing to the long-term development of public transit. Some conclusions can be drawn: 1) urban planning should be closely connected with urban transport planning; 2) the role of government is predominant to implement railtransit; 3) the facilifies of railtransit should be advanced, reliable and safe; 4) quality service should be match with rail facilities; 5) special service for the disabled, yound and senior should be advocated.

Issues and approaches to supporting timeliness and security in real-time database systems

Databases for real-time systems are essential in supporting time-critical applications. However, there has not been much work in supporting security in real-time database systems, although sensitive information must be safeguarded in real-time systems as well. In this paper we address the issues that need to be considered for supporting both requirements of timeliness and security in real-time database systems. We present an adaptive policy to achieve the balance between the two requirements dynamically. We also present the notion of flexible security and the specification language that allows the designer to specify important properties of the database at an appropriate level.

An Open Secure Mobile Agent Framework for SystemsManagement

The Mobile Agent (MA) technology is gaining importance in the distributed management of networks and services for heterogeneous environments. MA-based management systems could represent an interesting alternative to traditional tools built upon the client/server model, either SNMP- or CMIP-based. Two main requirements currently limit the acceptance of MA solutions for management: the need of interoperability and the request for security. Without security, management systems cannot suit global untrusted environments, such as the Internet; without interoperability, they cannot interact with existing tools and legacy systems. The paper describes an MA-based management system with security and interoperability as the two main design objectives. It is an open management framework that grants interoperability by providing compliance with CORBA, the most diffused standard in the area of object-oriented components. In addition, it is based on a thorough security model and provides a wide range of tools and mechanisms to build and enforce flexible security policies.

Flexible security policies for digital libraries

Flexible security policies for digital libraries

Optical fibres

Optical fibres are currently finding uses in a great many diverse areas such as communications, lighting, imaging and optical sensors. Basically they provide a means of carrying light between two points via a flexible secure medium. The purpose of this article is to explain how they operate, to show how they fit in with some of the applications mentioned above and finally to describe some simple circuitry and equipment which may be used to investigate the properties of fibres and which could be made the basis of more advanced projects.

SODA: A secure object-oriented database system

This paper describes a security model for object-oriented systems. The model supports a flexible data classification policy based on inheritance. The classification poligy allows for a smooth transition between rigid classification rules and unlimited polyinstantiation. The security model treats the data model as well as the computational model of object-oriented systems allowing more flexibility. This model trades an increase in complexity for a more flexible security model.