Security Mechanisms for the Internet

Security must be built into Internet Protocols for those protocols to offer their services securely. Many security problems can be traced to improper implementations. However, even a proper implementation will have security problems if the fundamental protocol is itself exploitable. Exactly how security should be implemented in a protocol will vary, because of the structure of the protocol itself. However, there are many protocols for which standard Internet security mechanisms, already developed, may be applicable. The precise one that is appropriate in any given situation can vary. We review a number of different choices, explaining the properties of each

A security analysis of email communications

The objective of this report is to analyse the security and privacy risks of email communications and identify technical countermeasures capable of mitigating them effectively. In order to do so, the report analyses from a technical point of view the core set of communication protocols and standards that support email communications in order to identify and understand the existing security and privacy vulnerabilities. On the basis of this analysis, the report identifies and analyses technical countermeasures, in the form of newer standards, protocols and tools, aimed at ensuring a better protection of the security and privacy of email communications. The practical implementation of each countermeasure is evaluated in order to understand its limitations and identify potential technical and organisational constrains that could limit its effectiveness in practice. The outcome of the above mentioned analysis is a set of recommendations regarding technical and organisational measures that when combined properly have the potential of more effectively mitigating the privacy and security risks of today's email communications.JRC.G.6-Digital Citizen Securit

A Floor Control Server in a Distributed Conference Service

The conferencing systems in IP Multimedia (IM) networks are going through restructuring, accomplished in the near future. One of the changes introduced is the concept of floors and floor control in its current form with matching entity roles. The Binary Floor Control Protocol (BFCP) is a novelty to be exploited in distributed tightly coupled conferencing services. The protocol defines the floor control server (FCS), which implements floor control giving access to shared resources. As the newest tendency is to distribute the conferencing services, the locations of different functionality units play an important role in developing the standards. The floor control server location is not yet single-mindedly fixed in different standardization bodies, and the debate goes on where to place it within the media server, providing the conferencing service. The thesis main objective is to evaluate two distinctive alternatives in respect the Mp interface protocol between the respective nodes, as the interface in relation to floor control is under standardization work at the moment. The thesis gives a straightforward preamble in IMS network, nodes of interest including floor control server and conferencing. Knowledge on several protocols – BFCP, SDP, SIP and H.248 provides an important background for understanding the functionality changes introduced in the Mp interface and therefore introductions on those protocols and how they are connected to the full picture is given. The actual analysis on the impact of the floor control server into the Mp reference point is concluded in relation to the locations, giving basic flows, requirements analysis including a limited implementation proposal on supporting protocol parameters. The overall conclusion of the thesis is that even if both choices are seemingly useful, not one of the locations is clearly the most suitable in the light of this work. The thesis suggests a solution having both possibilities available to be chosen from in separate circumstances, realized with consistent standardization. It is evident, that if the preliminary assumption for the analysis is kept regarding to only one right place for the floor control server, more work is to be done in connected areas to discover the one most appropriate location

Modularisation de la sécurité informatique dans les systèmes distribués

Addressing security in the software development lifecycle still is an open issue today, especially in distributed software. Addressing security concerns requires a specific know-how, which means that security experts must collaborate with application programmers to develop secure software. Object-oriented and component-based development is commonly used to support collaborative development and to improve scalability and maintenance in software engineering. Unfortunately, those programming styles do not lend well to support collaborative development activities in this context, as security is a cross-cutting problem that breaks object or component modules. We investigated in this thesis several modularization techniques that address these issues. We first introduce the use of aspect-oriented programming in order to support secure programming in a more automated fashion and to minimize the number of vulnerabilities in applications introduced at the development phase. Our approach especially focuses on the injection of security checks to protect from vulnerabilities like input manipulation. We then discuss how to automate the enforcement of security policies programmatically and modularly. We first focus on access control policies in web services, whose enforcement is achieved through the instrumentation of the orchestration mechanism. We then address the enforcement of privacy protection policies through the expert-assisted weaving of privacy filters into software. We finally propose a new type of aspect-oriented pointcut capturing the information flow in distributed software to unify the implementation of our different security modularization techniques.Intégrer les problématiques de sécurité au cycle de développement logiciel représente encore un défi à l’heure actuelle, notamment dans les logiciels distribués. La sécurité informatique requiert des connaissances et un savoir-faire particulier, ce qui implique une collaboration étroite entre les experts en sécurité et les autres acteurs impliqués. La programmation à objets ou à base de composants est communément employée pour permettre de telles collaborations et améliorer la mise à l’échelle et la maintenance de briques logicielles. Malheureusement, ces styles de programmation s’appliquent mal à la sécurité, qui est un problème transverse brisant la modularité des objets ou des composants. Nous présentons dans cette thèse plusieurs techniques de modularisation pour résoudre ce problème. Nous proposons tout d’abord l’utilisation de la programmation par aspect pour appliquer de manière automatique et systématique des techniques de programmation sécurisée et ainsi réduire le nombre de vulnérabilités d’une application. Notre approche se focalise sur l’introduction de vérifications de sécurité dans le code pour se protéger d’attaques comme les manipulations de données en entrée. Nous nous intéressons ensuite à l’automatisation de la mise en application de politiques de sécurité par des techniques de programmation. Nous avons par exemple automatisé l’application de règles de contrôle d’accès fines et distribuées dans des web services par l’instrumentation des mécanismes d’orchestration de la plate-forme. Nous avons aussi proposé des mécanismes permettant l’introduction d’un filtrage des données à caractère privée par le tissage d’aspects assisté par un expert en sécurité

Introdução de mecanismo de segurança em sistemas de correio eletronico ;

Orientador: Claudio Leonardo LucchesiDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de ComputaçãoResumo: Este trabalho tem por objetivo apresentar e avaliar um sistema criado para prover segurança ao ambiente de correio eletrônico do editor Emacs: o programa ProtegeMail. Construído na linguagem Emacs LISP, o ProtegeMail consiste em uma extensão dos subsistemas de correio eletrônico do Emacs (VM, RMAIL, MH-E e GNUS). Ele funciona como uma interface modular para chamar funções criptográficas existentes nos programas de segurança de e-mail PGP e RIPEM. Inicialmente, este trabalho apresenta e discute a funcionalidade, a ,segurança e os protocolos, padrões e programas relacionados com o conceito de correio eletrônico. Em seguida, apresenta os aspectos específicos da utilização de criptografia em correio eletrônico. Depois, descreve e compara os pacotes PGP e PEM. Também apresenta e analisa a escolha do Emacs como ambiente alvo. Por fim, descreve e avalia o sistema ProtegeMail, através de suas principais funções e da segurança que proporciona ao usuárioAbstract: The major goal of this work is to present and to evaluate a system created to provide security for the Emacs editor electronic mail environment: the ProtegeMail program. Developed with Emacs Lisp language, ProtegeMail consists of an Emacs e-mail subsystems (VM, RMAIL, MH-E and GNUS) extension. It operates like a modular interface, calling cryptographic functions existing in PGP and RIPEM e-mail security programs. First, this work presents and discusses the functionality, security, and the protocols, standards and programs related with electronic mail concept. It then presents specific aspects of criptography applied to electronic mail. After this, it describes and compares PGP and PEM packets. It also presents and analyzes the choice of Emacs as a target environment. Finally, it describes and evaluates the ProtegeMail system, through its main functions and the security that it provides to the userMestradoMestre em Ciência da Computaçã

Verfahren und Protokolle für sicheren Rechtsverkehr auf dezentralen und spontanen elektronischen Märkten

Die Arbeit thematisiert das Problem der fehlenden Rechtssicherheit aktueller elektronischer Märkte. Für das Szenario eines dezentralen elektronischen Marktplatzes wird eine verteilte Marktplattform vorgestellt, die einen sicheren Rechtsverkehr ermöglicht. Einer der Schwerpunkte der Arbeit stellt dabei der nachweisbare Zugang einer elektronischen Willenserklärung auf dem verteilten Marktplatz dar