Distributed systems usually contain objects with heterogeneous security requirements that pose important challenges on the underlying security mechanisms and especially in access control systems. Access control in distributed systems often relies on centralized security administration. Existing solutions for distributed access control do not provide the flexibility and manageability required. T...

This paper describes security issues for federated database management systems set up for managing distributed, heterogeneous and autonomous multilevel databases. It builds on our previous work in multilevel secure distributed database management systems and on the results of others’ work in federated database systems. In particular, we define a multilevel secure federated database system and d...

Load balancing is very important for achieving high performance in distributed computer systems which often consist of heterogeneous computing and communications resources. In this paper, we study a cooperative load balancing scheme for central-server node distributed systems (CCOOPIO) and evaluate its performance using simulations. The objective of CCOOP-IO is to minimize the mean response tim...

Distributed spooling systems exist for many homogeneoøs systems. In this paper we describe the overall architecture of a distributed spooling system for a heterogeneous environment. This system allows exchanging jobs among UNIX, VMS, VM/CMS, and MVS operating systems connected by a network which provides the internet protocol suite (tCr/IP). The system's primary purpose is remote printing, but ...

The grid computing system can support the execution of computationally intensive parallel and distributive applications. The main characteristics of grid computing and heterogeneous computing system are similar. A novel scheduling algorithm, called NHEFT is proposed in this paper to enhance the functions of heterogeneous Earliest-Finish time (HEFT) algorithm. The NHEFT algorithm works for a bou...

Distributed First Order Logic (DFOL) is a formalism introduced more than 10 years ago with the purpose of formalising distributed knowledge-based systems. In these systems, knowledge is scattered in a set of heterogeneous and interconnected modules. The original version of DFOL defined a set of primitives for the specification of a restricted subset of interconnections between knowledge modules...

  The primary characteristic of an Ultra-Large-Scale (ULS) system is ultra-large size on any related dimension. A ULS system is generally considered as a system-of-systems with heterogeneous nodes and autonomous domains. As the size of a system-of-systems grows, and interoperability demand between sub-systems is increased, achieving more scalable and dynamic access control system becomes an im...

Model-Driven Engineering has emerged as a software development paradigm that can assist in separating the issues of the problem space of a software system from the complexities of implementation in the solution space. As software systems have become more complex, a need for multiple abstractions to describe a single system has emerged. The development teams of these massive systems are also oft...

Agent technology has recently been proposed as an enabling technology to model and design heterogeneous distributed systems. Unfortunately, most of the research and development of software agents is currently based on proprietary design architectures. This has two main drawbacks: new agent systems are invented from scratch each time and distributed agents are usually not able to interoperate. T...

In parallel and distributed computing multiple computers are collectively utilized to simultaneously process a set of tasks to improve performance over that of a single processor [BSB01]. Often, such computing systems are constructed from a heterogeneous mix of machines that may differ in their capabilities, e.g., available memory, number of floating point units, clock speed, and operating syst...