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The way of Internet transmission greatly varies in terms of the provided quality of services. Some ways are more reliable than others. There are often compromises: the transmission path that offers the highest throughput may not be the one that offers the least delay or the lowest cost. Therefore, the "optimal" path for an Internet packet may depend on the application and / or user’s needs. Because the Internet itself does not have the ability to optimize the transmission path for a certain application or user, the IP protocol provides a (quite limited) feature for higher-level protocols to transmit information to Internet Layer about how they should treat a particular data packet. According to this issue, we developed a new application which provides a bandwidth management solution for TCP protocol according to the membership affiliation of a certain Microsoft Directory Service server group. This paper presents the new approach bandwidth management application for TCP/IP protocols.

In the current context of developing real-time applications and actual data networks access dynamic, organizations (public institutions, companies, etc.) there are turned into account by using important resources so that to provide data traffic with a manageable bandwidth for all users. Security policies and Quality of Service (QoS) on current networks need to be manually configured or transmitted as configuration scripts on hundreds or even thousands of network devices. This generates changes for extremely complicated trafficking policies. Considering the above, in this paper we are aiming to present a new type of bandwidth management application, targeted for particular users' group, depending on the prerogatives given by a Directory Service type server. The bandwidth control solution is shown using a JAVA developed application. Bandwidth limiting process is conducted by replacating and automatically run a java file, followed by the user's authenticating process on an Active Directory server. This paper presents the involved elements used to perform network bandwidth limitations, bandwidth tests and also the results obtained while testing the developed bandwidth control application.

In a world of the global communications, with continuous expansion to new horizons, which requires anytime and anywhere access to information sources, the need to manage the communication requirements is a very important issue. Traditional IP networks are facing difficulties in ensuring, to a user, a specific bandwidth[1] level for network access. Related to this matter, in this article we are proposing a bandwidth control solution, through the medium of a newly developed Java application. The bandwidth management process is realized taking account of the privileges arising from the user's membership to certain directory service group, by using Active Directory specific software components. This paper presents the endorsement elements for a proposed network management application, highlighting the performed tests, at the development level, and the results obtained with the aimed bandwidth control application.

Given the growing demands for network services based sometimes on reduced resources, efficient solutions are continuously developed in order to operate the network infrastructures in optimum conditions. From network management viewpoint, the main challenge is related to traffic management solutions using data flow limitations for some specific users while giving higher priorities to others. If for an internet user the bandwidth traffic limitation management is not a problem being managed by routers, in LAN/MAN corporation cases, this becomes more difficult when the control is to be applied out off routers management area. More, for different levels of users' hierarchy often particular QoS parameters are necessary regardless of the involved machines.

The video, voice, multimedia next-generation applications are using real-time data transmissions. Therefore, taking into account that all these applications are transmitted “over IP”, variable bandwidth has to be provided for specific situations in order to prevent network congestion. The active equipments meet these requirements and provide the network management. However, how will it be if the network equipments could be replaced by a software able to take over their capacities? The current paper presents a new approach concerning the setting of QoS parameters, by replacing the active network equipments with an application for data traffic limitations, providing a certain guaranteed bandwidth for a certain user, depending on the belonging to a certain group of users from “Active Directory”.

Since the data transmission networks require different bandwidth for simultaneous transmission of data, the new generation of network equipment use technologies that ensure QoS (Quality of Service) control services integrated data, video, voice and multimedia. This paper, demonstrate the test evaluation possibility of QoS parameters in a switch and the bandwidth limitation.

Systems theory has almost a century of existence. The rapidly expanding research development in areas like hybrid and cyber physical systems has raised new concepts and techniques that have not been integrated in systems theory. Examples include concepts like simulation/bisimulation, hierarchical evolution and control, and so on. In their nature, these concepts are highly interdisciplinary and transdisciplinary making difficult their study in a uniform way. In this paper, we propose a new doctrine for systems theory for capturing the essential properties of systems with complex dynamics like hybrid or stochastic behaviours. Our departing point is the basic idea from specification languages like VDM and Z, and modelling languages like UML and Modelica. The fundamental concept is that of symbolic dynamics where the state space can carry not only algebraic but also an analytic structure.

The varieties of possible interaction between computational systems and physical environments is at the heart of a new modeling paradigm called cyber-physical systems. In order to model and control these interactions it necessary to present the fundamental properties of physical environments in a formalism compatible with the computational structures, usually in a formal logic or an algebraic calculus. In this paper, we propose a model as a step towards reasoning about the problems of uncertainty and surprise in the context of cyber-physical systems operating under mixed human/autonomous control. In controlling embedded devices, human operators are, in most cases, assisted by automated controllers (like driving assistance systems and automatic pilots). A new issue appeared in many applications is to model the automatic controllers which are user centric, i.e. the controllers are carrying a runtime monitoring of the system behaviour in its environment, they inform and warn the user on safety hazardous situation and they take action only when the user fails to react. A robust controller should be able to operate in open, random environments and to assist the human operator in case of appearance of surprising, possible catastrophic situations.

Cyber-physical systems denote a new modeling paradigm that promotes a holistic view on complex systems. These systems have been studied before from various particular perspectives using paradigms like ubiquitous and distributed computing or embedded and hybrid systems. In modeling cyber-physical systems one has to consider the interaction between physics, computation and communication (networking), and a formal framework to studythis systems has to be invented. In this paper we develop a formal approach called Hilbertean formal methods to provide a denotational semantics for cyber-physical systems. We combine denotational semantics with an algebraic model for physical processes to model physical causality and observability.

Nowadays, there is an intense research activity in designing systems that operate in real life, physical environments. This research is spanned by various areas in computer science and engineering: embedded systems, reactive systems, wireless communications, hybrid systems, stochastic processes, etc. A severe limitation in the development of these systems is due to the mathematical foundation and complexity of the physical environment. Often, the physical environment is continuous and uncertain, and modelled in terms of continuous stochastic processes. These mathematics are quite different from the underlying mathematics of discrete controllers based on logic and algebra. In this paper, we make further developments of Hilbertean formal methods, an integrated specification framework based with a rich algebraic semantics. This framework axiomatises and abstracts away advanced structures from functional and stochastic analysis. We integrate a probabilistic version of Pi-calculus to provide a rigorous framework for embedded systems with mobile and adaptive communication structure. The integration mechanism is based on partial ordered sets. The resulting framework has the modelling power of connectionist models like neural networks. Moreover, we construct an energy integral to every specification. The power of formal specification and stochastic analysis are combined in a rigorous mathematical framework for the software development of embedded systems. In this way, we achieve a new foundation for the multidimensional codesign.

This paper presents a model of autonomy called autonomy with regard to an attribute applicable to cognitive and not cognitive artificial agents. Three criteria (global / partial, social / nonsocial, absolute / relative) are defined and used to describe the main characteristics of this type of autonomy.

In this work, we address the issue of handling complex continuous evolutions of the environment of embedded systems. There is now an impressive amount of research in the area of intelligent embedded controllers, and thus we do not need to argue about the importance of this subject.