Over fifty percent of all Swiss households have a PC;of these, most have Internet access. Who is not familiar with the many animations, sometimes attractive, sometimes less so, that pop up when you call up different w...
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Over fifty percent of all Swiss households have a PC;of these, most have Internet access. Who is not familiar with the many animations, sometimes attractive, sometimes less so, that pop up when you call up different websites? The enabling technology is called java and is now deployed in GSM mobile phones. java is set to revolutionise the European GSM world in a similar way to i-Mode in Japan. In Europe i-Mode will remain a proprietary interim solution until UMTS makes a breakthrough. If Wireless java is to achieve full compatibility in existing GSM networks binding standards will be needed, in particular for the terminals. Here the biggest constraint will be posed by slow expansion of the GSM standard. However, if Wireless java is to function faultlessly on all GSM mobile phones, rapid expansion is absolutely essential and would represent an important milestone along the road to success.
Foliage conducted a security-focused examination of the new offerings from Sun and Microsoft: Sun's java 2 JDK (J2SE) 1.4, java 2 Enterprise Edition (J2EE) 1.4 beta, and Microsoft's .NET 1.1. The examination c...
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Foliage conducted a security-focused examination of the new offerings from Sun and Microsoft: Sun's java 2 JDK (J2SE) 1.4, java 2 Enterprise Edition (J2EE) 1.4 beta, and Microsoft's .NET 1.1. The examination compared and contrasted the mechanisms present in both frameworks that are needed to architect and implement secure systems. The particular mechanisms identified fall into the following categories: Code Containment;Code and Data Protection;Secure Communications;Code-based Access Control;User Authentication;User-based and Role-based Access Control;Auditing and Tracking;This paper's conclusion presents a scorecard summarizing the findings. Not surprisingly, each framework has its strong and weak points. .NET has clear advantages in the areas of code and data protection and code-based access control, while java supplies a much more flexible solution for secure communications. Both are disappointing in the area of auditing and tracking.
This paper describes a java API that provides the possibility of accessing a native implementation of PGP. The interaction between C and java is based on the java Native Interface (JNI) which has been included in the ...
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ISBN:
(纸本)9608052629
This paper describes a java API that provides the possibility of accessing a native implementation of PGP. The interaction between C and java is based on the java Native Interface (JNI) which has been included in the java Development Kit (JDK) since version 1.1. The implementation allows to use available PGP implementations in C and, therefore, provides significant performance and security benefits. The paper describes the implementation and compares its performance with another approach based on invoking shell scripts.
The goal of points-to analysis for java is to determine the set of objects pointed to by a reference variable or a reference objet field. Improving the precision of practical points-to analysis is important because po...
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ISBN:
(纸本)9781581135626
The goal of points-to analysis for java is to determine the set of objects pointed to by a reference variable or a reference objet field. Improving the precision of practical points-to analysis is important because points-to information has a wide variety of client applications in optimizing compilers and software engineering tools. In this paper we present object sensitivity, a new form of context sensitivity for flow-insensitive points-to analysis for java. The key idea of our approach is to analyze a method separately for each of the objects on which this method is invoked. To ensure flexibility and practicality, we propose a parameterization framework that allows analysis designers to control the tradeoffs between cost and precision in the object-sensitive analysis.Side-effect analysis determines the memory locations that may be modified by the execution of a program statement. This information is needed for various compiler optimizations and software engineering tools. Wepresent a new form of side-effect analysis for java which is based on object-sensitive points-to *** have implemented one instantiation of our parameterized object-sensitive points-to analysis. We compare this instantiation with a context-insensitive points-to analysis for java which is based on Andersen's analysis for C [4]. On a set of 23 java programs, our experiments show that the two analyses have comparable cost. In some cases the object-sensitive analysis is actually faster than the context-insensitive analysis. Our results also show that object sensitivity significantly improves the precision of side-effect analysis, call graph construction, and virtual call resolution. These experiments demonstrate that object-sensitive analyses can achieve significantly better precision than context-insensitive ones, while at the same time remaining efficient and practical.
Open distributed systems are becoming increasingly popular. Such systems include components that may be obtained from a number of different sources. For example, java allows run-time loading of software components res...
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ISBN:
(纸本)9781581135626
Open distributed systems are becoming increasingly popular. Such systems include components that may be obtained from a number of different sources. For example, java allows run-time loading of software components residing on remote machines. One unfortunate side-effect of this openness is the possibility that "hostile" software components may compromise the security of both the program and the system on which it runs. java offers a built-in security mechanism, using which programmers can give permissions to distributed components and check these permissions at run-time. This security model is flexible, but using it is not straightforward, which may lead to insufficiently tight permission checking and therefore breaches of *** this paper, we propose a data flow algorithm for automated analysis of the flow of permissions in java programs. Our algorithm produces, for a given instruction in the program, a set of permissions that are checked on all possible executions up to this instruction. This information can be used in program understanding tools or directly for checking properties that assert what permissions must always be checked before access to certain functionality is allowed. The worst-case complexity of our algorithm is low-order polynomial in the number of program statements and permission types, while comparable previous approaches have exponential costs.
This article focuses on communication management experiences and its effect on e-commerce. Effective e-commerce relies on an efficient and precise information interchange between participating stakeholders, using the ...
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This article focuses on communication management experiences and its effect on e-commerce. Effective e-commerce relies on an efficient and precise information interchange between participating stakeholders, using the existing infrastructure. The Internet and intranet communication facilities are making the amount of available information quite large, and it continues to increase progressively. Experiences using a multi-agent system (MAS)- based intermediation service for e-commerce, implemented with computer software java and CORBA are described in this article, with emphasis on communication and management system activities. Using java as the communication medium between modules inside each domain allows higher speed than using CORBA but requires replacing call-back versatility with a more complex implementation code. At the same time, the application environment does not tend to be extremely distributed or heterogeneous, so that CORBA utilization in intradomain communications could be justified.
When the java programming language was introduced by Sun Microsystems in 1995, there was a perception (properly founded at the time) that its many benefits came at a significant performance cost. The related deficienc...
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When the java programming language was introduced by Sun Microsystems in 1995, there was a perception (properly founded at the time) that its many benefits came at a significant performance cost. The related deficiencies were especially apparent in numerical computing. Our own measurements in 1997 with second-generation java Virtual Machines (JVMs) found differences in performance of up to one hundredfold relative to C and Fortran. Initial experience with poor performance caused many developers of high-performance numerical applications to reject java out-of-hand as a platform for their applications.
Computational reflection is gaining interest in practical applications as witnessed by the use of reflection in the javaprogramming environment and recent work on reflective middleware. Reflective systems offer many ...
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Computational reflection is gaining interest in practical applications as witnessed by the use of reflection in the javaprogramming environment and recent work on reflective middleware. Reflective systems offer many different reflection programming interfaces, the so-called Meta-Object Protocols (MOPs). Their design is subject to a number of constraints relating to, among others, expressive power, efficiency and security properties. Since these constraints are different from one application to another, it would be desirable to easily provide specially-tailored MOPs. In this paper, we present a generic reification technique based on program transformation. It enables the selective reification of arbitrary parts of object-oriented meta-circular interpreters. The reification process is of fine granularity: individual objects of the run-time system can be reified independently. Furthermore, the program transformation can be applied to different interpreter definitions. Each resulting reflective implementation provides a different MOP directly derived from the original interpreter definition.
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