Data and Application Secutiry for Distributed Application Hosting Services

The cost of creating and maintaining software and hardware infrastructures for delivering web services led to a notable trend toward the use of application service providers (ASPs) and, more generally, distributed application hosting services (DAHSs). The emergence of enabling technologies, such as J2EE and .NET, has contributed to the acceleration of this trend. DAHSs rent out Internet presence, computation power, and data storage space to clients with infrastructural needs. Consequently, they are cheap and effective outsourcing solutions for achieving increased service availability and scalability in the face of surges in demand. However, ASPs and DAHSs operate within the complex, multi-tiered, and open Internet environment and, hence, they introduce many security challenges that have to be addressed effectively to convince customers that outsourcing their IT needs is a viable alternative to deploying complex infrastructures locally. In this chapter, we provide an overview of typical security challenges faced by DAHSs, introduce dominant security mechanisms available at the different tiers in the information management hierarchy, and discuss open challenges

A Flexible Authorization Framework

Advances in application areas such as Internet-based transactions, cooperating coalitions, and workflow systems have brought new challenges to access control. In order to meet the diverse needs of emerging applications, it has become necessary to support multiple access control policies in one security domain. This chapter describes an authorization framework, referred to as the Flexible Authorization Framework (FAF), which is capable of doing so. FAF is a logic-based framework in which authorizations are specified in terms of a locally stratified rule base. FAF allows permissions and prohibitions to be included in its specification. FAF specifications can be changed by deleting and inserting its rules. We also describe FAF’s latest additions, such as revoking granted permissions, provisional authorizations, and obligations.

Multimedia Security and Digital Rights Management Technology

Multimedia content delivery applications are becoming widespread thanks to increasingly cheaper access to high bandwidth networks. Also, the pervasiveness of XML as a data interchange format has given origin to a number of standard formats for multimedia, such as SMIL for multimedia presentations, SVG for vector graphics, VoiceXML for dialog, and MPEG-21 and MPEG-7 for video. Innovative programming paradigms (such as the one of web services) rely on the availability of XML-based markup and metadata in the multimedia flow in order to customize and add value to multimedia content distributed via the Net. In such a context, a number of security issues around multimedia data management need to be addressed. First of all, it is important to identify the parties allowed to use the multimedia resources, the rights available to the parties, and the terms and conditions under which those rights may be executed: this is fulfilled by the Digital Rights Management (DRM) technology. Secondly, a new generation of security and privacy models and languages is needed, capable of expressing complex filtering conditions on a wide range of properties of multimedia data. In this chapter, we analyze the general problem of multimedia security. We summarize the most important XML-based formats for representing multimedia data, and we present languages for expressing access control policies. Finally, we introduce the most important concepts of the DRM technology.

Digital Certificates and Public-Key Infrastructures

The technical solutions and organizational procedures used to manage certificates are collectively named Public Key Infrastructure (PKI). The overall goal of a PKI is to provide support for usage of public-key certificates within – and also outside – its constituency. To this aim, several functions are needed, such as user registration, key generation, certificate revocation and many others. It is the aim of this paper to describe issues related to digital certificates and PKIs, both from the technical and management viewpoint.

Comparing the Security Architectures of Sun ONE and Microsoft .NET

Platforms for web services have been reduced to two basic approaches: Microsoft .NET and Sun ONE (J2EE). We compare here these two platforms with respect to the security they provide to the web services that use them. We arrive to the conclusion that although the basic security architectures are fairly similar, their actual implementations differ. Microsoft’s approach appears weaker because of their self-contained approach, and a failure to follow good principles of software and secure systems design.

Secure Data Dissemination

In this chapter, we present the main security issues related to the selective dissemination of information (SDI system). More precisely, after provided an overview of the work carried out in this field, we have focused on the security properties that a secure SDI system (SSDI system) must satisfy and on some of the strategies and mechanisms that can be used to ensure them. Indeed, since XML is the today emerging standard for data exchange over the Web, we have casted our attention on Secure and Selective XML data dissemination (SSXD). As a result, we have presented a SSXD system providing a comprehensive solution to XML documents. In the proposed chapter, we also consider innovative architecture for the data dissemination, by suggesting a SSXD system exploiting the third-party architecture, since this architecture is receiving growing attention as a new paradigm for data dissemination over the web. In a third-party architecture, there is a distinction between the Owner and the Publisher of information. The Owner is the producer of the information, whereas Publishers are responsible for managing (a portion of) the Owner information and for answering user queries. A relevant issue in this architecture is how the Owner can ensure a secure dissemination of its data, even if the data are managed by a third-party. Such scenario requires a redefinition of dissemination mechanisms developed for the traditional SSXD system. Indeed, the traditional techniques cannot be exploited in a third party scenario. For instance, let us consider the traditional digital signature techniques, used to ensure data integrity and authenticity. In a third party scenario, that is, a scenario where a third party may prune some of the nodes of the original document based on user queries, the traditional digital signature is not applicable, since its correctness is based on the requirement that the signing and verification process are performed on exactly the same bits.

Architectures for Advanced Cryptographic Systems

In the last 20-30 years, the world of modern cryptography has been largely dominated by traditional systems such as the Data Encryption Standard and the RSA algorithm. Such systems have provided a secure way for storing and transmitting information and they are nowadays incorporated in many network protocols and secure storage media. More recently, the increasing advance of crypto-analytical techniques and tools and the emergence of new applications, for example wireless communications and mobile computing, have stimulated the research and development of innovative cryptographic algorithms. These newer systems require a more detailed and sophisticated mathematical formalization and operations, which are not normally supported by general-purpose processors. For example, many basic operations required to implement recently proposed cryptographic algorithms, such as the Advanced Encryption Standard or Elliptic Curve Cryptosystems, are based on arithmetic in finite fields (or Galois fields). This chapter is, thus, intended to give an overview of such developments in modern cryptography. In particular, it aims at giving the reader a comprehensive understanding of innovative cryptosystems, their basic structure, alternative existing hardware architectures to implement them, and their performance requirements and characterizations. Emphasis will be made throughout on two important cases: the Advanced Encryption Standard and Elliptic Curve Cryptosystems.

Smart Card Applications and Systems

Securing data is becoming of the utmost strategic importance in today’s digital environment. Open wide networks such as the Internet and inter-dependencies of modern systems have reshaped security requirements of smart card platforms. Smart card chips have been designed for 20 years to protect data and resist against attacks. Design mechanisms, cryptography, software implementation and certification process have all been introduced to provide efficient tamper resistant techniques against piracy. These techniques are re-used by a semiconductor industry demanding even more security. At the same time, smart card industry tries to address this demand and modify its positioning. This global convergence slightly impact new modern integrated systems.

Enforcing Privacy on the Semantic Web

Over the past few years there has been a huge influx of web accessible information. Information access and storage methods have grown considerably. Previously unknown or hard-to-get information is now readily available to us. The World Wide Web has played an important role in this information revolution. Often, sensitive information is exchanged among users, Web services, and software agents. This exchange of information has highlighted the problem of privacy. A large number of strategies employed to preserve people’s privacy require users to define their respective privacy requirements and make decisions about the disclosure of their information. Personal judgments are usually made based on the sensitivity of the information and the reputation of the party to which the information is to be disclosed. In the absence of a comprehensive privacy preserving mechanism, no guarantees about information disclosure can be made. The emerging Semantic Web is expected to make the challenge more acute in the sense that it would provide a whole infrastructure for the automation of information processing on the Web. On the privacy front, this means that privacy invasion would net more quality and sensitive personal information. In this chapter, we describe a reputation-based approach to automate privacy enforcement in a Semantic Web environment. We propose a reputation management system that monitors Web services and collects, evaluates, updates, and disseminates information related to their reputation for the purpose of privacy protection.