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Showing papers on "Cognitive network published in 2003"


Journal ArticleDOI
TL;DR: For the multicast setup it is proved that there exist coding strategies that provide maximally robust networks and that do not require adaptation of the network interior to the failure pattern in question.
Abstract: We take a new look at the issue of network capacity. It is shown that network coding is an essential ingredient in achieving the capacity of a network. Building on recent work by Li et al.(see Proc. 2001 IEEE Int. Symp. Information Theory, p.102), who examined the network capacity of multicast networks, we extend the network coding framework to arbitrary networks and robust networking. For networks which are restricted to using linear network codes, we find necessary and sufficient conditions for the feasibility of any given set of connections over a given network. We also consider the problem of network recovery for nonergodic link failures. For the multicast setup we prove that there exist coding strategies that provide maximally robust networks and that do not require adaptation of the network interior to the failure pattern in question. The results are derived for both delay-free networks and networks with delays.

2,628 citations


Journal ArticleDOI
TL;DR: A new engineering approach for cognitive systems, implemented by the COSA framework, which may be a crucial step forward to achieve a wide-spread application of cognitive systems.
Abstract: This article presents an overview of COSA, a cognitive system architecture, which is a generic framework proposing a unified architecture for cognitive systems. Conventional automation and similar systems lack the ability of cooperation and cognition, leading to serious deficiencies when acting in complex environments, especially in the context of human-computer interaction. Cognitive systems based on cognitive automation can overcome these deficiencies. Designing such artificial cognitive systems can be considered a very complex software development process. Although a number of developments of artificial cognitive systems have already demonstrated great functional potentials in field tests, the engineering approach of this kind of software is still a candidate for further improvement. Therefore, wide-spread application of cognitive systems has not been achieved yet. This article presents a new engineering approach for cognitive systems, implemented by the COSA framework, which may be a crucial step forward to achieve a wide-spread application of cognitive systems. The approach is based on a new concept of generating cognitive behaviour, the cognitive process (CP). The CP can be regarded as a model of the human information processing loop whose behaviour is solely driven by "a-priori knowledge". The main features of COSA are the implementation of the CP as its kernel and the separation of architecture from application leading to reduced development time and increased knowledge reuse. Additionally, separating the knowledge modelling process from behaviour generation enables the knowledge designer to use the knowledge representation that is best suited to his modelling problem. A first application based on COSA implements an autonomous unmanned air vehicle accomplishing a military reconnaissance mission. Some of the application experiences with the new approach are presented.

46 citations


Proceedings ArticleDOI
09 Apr 2003
TL;DR: By introducing the concepts of aggregation and hierarchical directory into the P2P network, a new type of P1P network model is proposed that is suitable for resource discovery in large peer based networks.
Abstract: Peer-to-peer (P2P) networking technology is a currently emerging technology in the network research domain. The research of P2P network architecture is an important problem in the investigation of P2P network models are analyzed. Each of these two models has many problems itself, which makes it not a suitable solution for resource discovery in large peer based networks. By introducing the concepts of aggregation and hierarchical directory into the P2P network, a new type of P2P network model is proposed.

26 citations


Proceedings ArticleDOI
04 May 2003
TL;DR: The main building blocks of a simulation environment of the OSI network layer of packet-switching networks are described and the need for such a tool is presented and pitfalls of previous solutions are described.
Abstract: This paper describes the main building blocks of a simulation environment of the OSI network layer of packet-switching networks. The need for such a tool is presented and pitfalls of previous solutions are described. Remedies provided by the most recent solution are discussed. Architecture, organisation, and architectural decisions are explained.

25 citations


Proceedings ArticleDOI
04 May 2003
TL;DR: A cellular automaton model of the OSI network layer used to model additional wired and wireless connections in LANs and WANs is presented and it is observed that throughput is maximal at the critical load of the network.
Abstract: We present a cellular automaton model of the OSI network layer. Our focus is on parameters that can affect flow and congestion in the network, such as randomly inserted additional links, used to model additional wired and wireless connections in LANs and WANs. We present selected simulation results and observe, in accordance with other models, that throughput is maximal at the critical load of the network. Further, the addition of links increases the critical load of a network if queueing costs are taken into account in routing decisions for packets.

23 citations


01 Jan 2003
TL;DR: This work describes a DyTR experiment in which trust assessment is coupled with resource delegation mechanisms in a simulated dynamic network environment.
Abstract: The Dynamic Trust-based Resources (DyTR) system applies a dynamic notion of trust to ad hoc network resources. DyTR continuously assesses the trustworthiness of entities over time based on system events and controls network resources according to current levels of trust. For dynamic trust assessment, DyTR utilizes a socio-cognitive model of trust, a formal model of the essential concepts and characteristics of trust in human society, and subjective logic for reasoning about trust-relevant system events. We describe a DyTR experiment in which trust assessment is coupled with resource delegation mechanisms in a simulated dynamic network environment.

13 citations


Proceedings ArticleDOI
02 Apr 2003
TL;DR: An integrated management approach for service and network management in the case of heterogeneous and mobile network access, based on the cooperative association between QoS Brokers and Authentication, Authorization, Accounting and Charging (AAAC) systems is proposed.
Abstract: This paper describes a global quality of service architecture for mobile, audited and accountable environments. Target networks are "Beyond 3rd Generation Networks", where several heterogeneous access networks are available to the user. Providing per user and per service differentiated QoS is a key issue in these networks. The paper proposes an integrated management approach for service and network management in the case of heterogeneous and mobile network access, based on the cooperative association between QoS Brokers and Authentication, Authorization, Accounting and Charging (AAAC) systems.

11 citations


Book ChapterDOI
03 Nov 2003
TL;DR: It is shown how “self-awareness”, through on-line self-monitoring and measurement, coupled with intelligent adaptive behaviour in response to observed data, can be used to offer quality of service to network users based on the “Cognitive Packet Network” (CPN) design.
Abstract: We show how “self-awareness”, through on-line self-monitoring and measurement, coupled with intelligent adaptive behaviour in response to observed data, can be used to offer quality of service to network users based on the “Cognitive Packet Network” (CPN) design.

7 citations


Journal ArticleDOI
Stephen F. Bush1
TL;DR: The architecture and initial feasibility results of a proto-type communication network that utilizes genetic programming to evolve services and protocols as part of network operation are presented.
Abstract: This article presents the architecture and initial feasibility results of a proto-type communication network that utilizes genetic programming to evolve services and protocols as part of network operation. The network evolves responses to environmental conditions in a manner that could not be pre-programmed within legacy network nodes a priori. A priori in this case means before network operation has begun. Genetic material is exchanged, loaded, and run dynamically within an active network. The transfer and execution of code in support of the evolution of network protocols and services would not be possible without the active network environment. Rapid generation of network service code occurs via a genetic programming paradigm. Complexity and algorithmic information theory play a key role in understanding and guiding code evolution within the network.

7 citations


Book
01 Jan 2003
TL;DR: 1. Telecommunications a general survey: Numerization of the analogue signal common codes transmission modes modulation signal transmission types of link link assemblies terminals transmission supports - cable, herzian, satellite data transmission systems numerical plesiochronic andsynchronous hierarchy.
Abstract: 1. Telecommunications a general survey: Numerization of the analogue signal common codes transmission modes modulation signal transmission types of link link assemblies terminals transmission supports - cable, herzian, satellite data transmission systems numerical plesiochronic andsynchronous hierarchy. 2. Network architecture: Normalisation Open system architecture layer architecture (levels 1 to 7) reference model, norms and other protocols TCP/IP protocol, internet. 3. Networks: Presentation Transpac and shared networks videotext local networks research networks satellite communication telecommunication networks with mobiles network images, video and multiservices numerical networks and integration of services high flow network optical networks access networks, high rate internet networks intelligent networks QoS in network IP and the internet evolution of networks new generation networks. 4. Administration of networks: General presentation normalisation management OSI norms general architecture of OSI management SNMO protocol management of networks and services approach through processes. Modelisation, perspectives of evolution the telecom operator evolution of administrative function of networks administrative outcomes of proposed networks. Annexes Bibliography Glossary Index

6 citations


01 Jan 2003
TL;DR: Using an integrated task network model with a cognitive architecture to assess the impact of technological aids on pilot performance and the results show clear trends in pilot performance are positive.
Abstract: (2003). Using an integrated task network model with a cognitive architecture to assess the impact of technological aids on pilot performance.

Proceedings ArticleDOI
Haitao Tang1
07 Sep 2003
TL;DR: The concept and issues to distribute the soft handover functions from a centralized RAN entity into many entities of a distributed RAN, and the reasons for the distribution and the approaches to realize it are introduced.
Abstract: This paper introduces the concept and issues to distribute the soft handover (e.g., RNC and MDC) functions from a centralized RAN entity into many entities of a distributed RAN. It also elaborates the reasons for the distribution and the approaches to realize it. The distribution of the soft handover functions keeps the benefit of soft handover and, at the same time, prevents the extra consumption of network resource that a soft handover of the RNC-centralized RAN can incur. The distribution of the function also gives other benefits such as higher network reliability, higher robustness on a given network fault, more flexible network operation and management, and lower combined network costs. This work also introduces the issues of soft handover interoperability among the centralized RAN and the distributed RANs, and between possibly different soft handover solutions inside a distributed RAN.

Proceedings ArticleDOI
02 Apr 2003
TL;DR: A model is developed to support how the network-based services interact the design of networks with complementary components under certainty and preliminary results showed that there exists a complementarity between network components.
Abstract: The notion of modularity has been given much attention in network industry because the rapid changes of technology and customer preferences require flexible network architecture. However, the effectiveness of modular design may be limited by the loss of complementarity in network design. The goal of this study is to measure the effects of complementarity in network design. A model is developed to support how the network-based services interact the design of networks with complementary components under certainty. Preliminary results showed that there exists a complementarity between network components.