When admitting electronic media as a means for citizens to approach public authorities (e-government), security is an indispensable precondition for concerns of legal certainty and for achieving acceptance by the citizens. While the security-enabling technologies such as smartcards, digital signatures, and PKI are mature, questions of scalability, technology-neutrality, and forward-compatibility arise when being deployed on the large scale. The security architecture of the Austrian citizen card is presented. We briefly present the legal provisions that enable e-government. We then reflect on requirements to be fulfilled to achieve a lasting security architecture that provides swift deployment of applications, but provides the flexibility to not discriminate against service providers and technologies that will emerge in future. The concept called "security layer" is discussed as the core part of the security architecture, which basically is an open interface that hides the security-relevant functionality of the citizen card on a high abstraction level. A few e-government applications that are being launched in the short-term are sketched.

The ATM Forum international consortium recently approved the first version of its security specifications aiming to protect communications over Asynchronous Transfer Mode (ATM) networks by offering data confidentiality, partner authentication, etc. The paper describes the architecture of one of the first ATM Forum compliant security prototypes being currently developed in the European project SCAN (Secure Communications in ATM Networks). Additionally to the security management functions specified by the ATM Forum to exchange encryption keys and negotiate security services, SCAN implements the possibility for end users to modify the data flow encryption algorithm during a connection in progress, and the possibility to keep the encryption algorithm choice confidential. Moreover, a flexible implementation is offered allowing future users to develop their own security protocols and their own ATM security monitoring applications.

Faced with the migration towards broadband networking technologies, formerly visionary applications, as diverse as teleworking, telemedicine or electronic commerce, are expected to emerge to broad usage. This makes confidential communication in broadband networks a challenging basic condition. In this paper, we present an ATM encryption model that is focused on independence of both the hardware of the end-user device and the application utilizing ATM as a transport medium. Therefore, the ATM cell stream is intercepted by a high-speed data encryption standard (DES), TripleDES encryption hardware, using well-defined standardized interfaces. Considering the various access rates that ATM is defined for, the encryption unit that is being developed is designed to be independent of the physical media and capable of supporting transmission rates of up to 155 Mbps. Thus, the solution is applicable to broadband integrated services digital network (B-ISDN) end-user devices, ranging from narrowband to multi-Mbps access rates.

Residue number systems provide a good means for extremely long integer arithmetic. Their carry-free operations make parallel implementations feasible. Some applications involving very long integers, such as public key encryption, rely heavily on fast modulo reductions. This paper shows a new combination of residue number systems with efficient modulo reduction methods. Two methods are compared, and the faster one is scrutinized in detail. Both methods have the same order of complexity, O(log n), with n denoting the amount of registers involved.>

Abstract The paper deals with strategies to implement comfort classes and with fixed optimization criteria.

A new computer system is required to replace the existing UNIVAC 494 system for the universities at Graz. A synthetic jobstream matching the real batch load of the existing system was constructed using Buchholz's job (which was modified and transferred to FORTRAN). This synthetic jobstream was used for comparison of different computer systems as well as for the selection evaluation process itself. The construction of this synthetic jobstream is described in detail in this paper. The problems of characterising the real load are discussed explicitly. Special attention was given to the question of which parameters should be used, together with the decisions on the form of the scale and the sub-division of the range of the parameter values. Furthermore a procedure is given for an optimum of determination of the parameter values of the synthetic jobstream.