5 research outputs found
Developing a security mechanism for software agents
Thesis (Master)--Izmir Institute of Technology, Computer Engineering, Izmir, 2006Includes bibliographical references (leaves: 73-76)Text in English; Abstract: Turkish and Englishx 76 leavesThis thesis proposes a message security solution on multi-agent systems. A general security analysis based on properties of software agents is presented along with an overview of security measures applicable to multi-agent systems. A security design and implementation has been developed to protect communication among agents. And this implementation scheme has been applied to Seagent, a semantic web enabled multi-agent framework. Hence, a set of agent security mechanisms have been adapted for Seagent and have been implemented for message confidentiality, integrity, authentication and nonrepudiation. Then these mechanisms have been tested for communication performance on Seagent
Multi-agent system security for mobile communication
This thesis investigates security in multi-agent systems for mobile communication.
Mobile as well as non-mobile agent technology is addressed.
A general security analysis based on properties of agents and multi-agent systems
is presented along with an overview of security measures applicable to
multi-agent systems, and in particular to mobile agent systems.
A security architecture, designed for deployment of agent technology in a mobile
communication environment, is presented. The security architecture allows
modelling of interactions at all levels within a mobile communication system.
This architecture is used as the basis for describing security services and mechanisms
for a multi-agent system. It is shown how security mechanisms can be
used in an agent system, with emphasis on secure agent communication.
Mobile agents are vulnerable to attacks from the hosts on which they are executing.
Two methods for dealing with threats posed by malicious hosts to a
trading agent are presented. The rst approach uses a threshold scheme and
multiple mobile agents to minimise the eect of malicious hosts. The second
introduces trusted nodes into the infrastructure.
Undetachable signatures have been proposed as a way to limit the damage a
malicious host can do by misusing a signature key carried by a mobile agent.
This thesis proposes an alternative scheme based on conventional signatures and
public key certicates.
Threshold signatures can be used in a mobile agent scenario to spread the risk
between several agents and thereby overcome the threats posed by individual
malicious hosts. An alternative to threshold signatures, based on conventional
signatures, achieving comparable security guarantees with potential practical
advantages compared to a threshold scheme is proposed in this thesis.
Undetachable signatures and threshold signatures are both concepts applicable
to mobile agents. This thesis proposes a technique combining the two schemes
to achieve undetachable threshold signatures.
This thesis denes the concept of certicate translation, which allows an agent
to have one certicate translated into another format if so required, and thereby
save storage space as well as being able to cope with a certicate format not
foreseen at the time the agent was created
Securing open multi-agent systems governed by electronic institutions
One way to build large-scale autonomous systems is to develop an open multi-agent system
using peer-to-peer architectures in which agents are not pre-engineered to work together and in
which agents themselves determine the social norms that govern collective behaviour. The social
norms and the agent interaction models can be described by Electronic Institutions such as those
expressed in the Lightweight Coordination Calculus (LCC), a compact executable specification
language based on logic programming and pi-calculus. Open multi-agent systems have
experienced growing popularity in the multi-agent community and are expected to have many
applications in the near future as large scale distributed systems become more widespread, e.g.
in emergency response, electronic commerce and cloud computing. A major practical limitation
to such systems is security, because the very openness of such systems opens the doors to
adversaries for exploit existing vulnerabilities.
This thesis addresses the security of open multi-agent systems governed by electronic
institutions. First, the main forms of attack on open multi-agent systems are introduced and
classified in the proposed attack taxonomy. Then, various security techniques from the literature
are surveyed and analysed. These techniques are categorised as either prevention or detection
approaches. Appropriate countermeasures to each class of attack are also suggested.
A fundamental limitation of conventional security mechanisms (e.g. access control and
encryption) is the inability to prevent information from being propagated. Focusing on
information leakage in choreography systems using LCC, we then suggest two frameworks to
detect insecure information flows: conceptual modeling of interaction models and language-based
information flow analysis. A novel security-typed LCC language is proposed to address
the latter approach.
Both static (design-time) and dynamic (run-time) security type checking are employed to
guarantee no information leakage can occur in annotated LCC interaction models. The proposed
security type system is then formally evaluated by proving its properties. A limitation of both
conceptual modeling and language-based frameworks is difficulty of formalising realistic
policies using annotations.
Finally, the proposed security-typed LCC is applied to a cloud computing configuration case
study, in which virtual machine migration is managed. The secrecy of LCC interaction models
for virtual machine management is analysed and information leaks are discussed