Broadband Integrated Services Network Research Articles

A Method of Topology Discovery for Switched Ethernet Based on Address Forwarding Tables

In this paper, the connections reasoning technique (CRT) based on the predication logic is proposed to infer the connections between network nodes. This technique interprets the address forwarding tables (AFTs) as a set of predicate formulas and translates the topology discovery into a mathematic problem of logic reasoning, so that the topology discovery can be studied by resorting to mathematic tools. An algorithm for topology discovery based on CRT is proposed in this paper. Compared with current discovery algorithms, this method excels in: 1) Applying the redundancies in AFTs more effectively, so that the whole topology can be built up by just small part of AFTs; 2) Naturally resolving the problem of topology discovery for multi-subnet switched domain without any extensions. Furthermore, a method with little cost is proposed to discover the dynamic topology in this paper. This algorithm is successfully applied to the network management system for CBISN (Community Broadband Integrated Services Network).

Unified Approach for QoS Management with Adaptation and Renegotiation

A new adaptation protocol for quality of service (QoS) adaptation with renegotiation is developed that allows a connection-oriented network like ATM to recover from the QoS violations in order to satisfy end-to-end QoS requirements. This protocol is applicable to networks using PNNI where the nodes are grouped together in peer groups hierarchically. It Is assumed that every node has a QoS/Route Monitor unit that receives QoS/Link State Update (LSU) messages from the network on a periodic or triggered basis. In addition to its usual functions, this monitor would also function as QoS agent, QoS manager or Connection QoS Manager depending on its location. The QoS/Route Monitor is responsible for sending or receiving the signalling messages required in the protocol. To facilitate functioning of the protocol, several signalling messages have been defined that characterize different control mechanisms required for the protocol and the network. Finally, a unified model for quality of service management in broadband integrated services networks is proposed that has QoS monitor as primary part of the network interface or the switch. The model consists of components responsible for QoS provisioning, QoS monitoring and managing QoS routes. The model is also responsible for processing the proposed adaptation protocol between end points.

A comparison of two optimal approaches for the MCOP problem

Providing guaranteed end-to-end quality of service (QoS) is a key issue for deploying multimedia applications on the broadband integrated services networks. To support QoS-based services, an optimal path determination problem, which concerns how to select a feasible end-to-end path to simultaneously satisfy multiple QoS constraints, has to be studied. This problem is often referred as the multiple constrained optimal path problem. Two optimal algorithms: branch-and-bound and extended Bellman–Ford algorithms (EBFA) are proposed in this paper for this NP-complete problem. A number of simulations for different network topologies were carried out for comparing performances between these two algorithms. The experimental results show that the branch-and-bound based algorithm not only outperforms the EBFA, but also is an efficient and stable method when it applies to random networks and practical networks like ANSNET.

Genetic algorithm-based neural fuzzy decision tree for mixed scheduling in ATM networks

Future broadband integrated services networks based on asynchronous transfer mode (ATM) technology are expected to support multiple types of multimedia information with diverse statistical characteristics and quality of service (QoS) requirements. To meet these requirements, efficient scheduling methods are important for traffic control in ATM networks. Among general scheduling schemes, the rate monotonic algorithm is simple enough to be used in high-speed networks, but does not attain the high system utilization of the deadline driven algorithm. However, the deadline driven scheme is computationally complex and hard to implement in hardware. The mixed scheduling algorithm is a combination of the rate monotonic algorithm and the deadline driven algorithm; thus it can provide most of the benefits of these two algorithms. In this paper, we use the mixed scheduling algorithm to achieve high system utilization under the hardware constraint. Because there is no analytic method for schedulability testing of mixed scheduling, we propose a genetic algorithm-based neural fuzzy decision tree (GANFDT) to realize it in a real-time environment. The GANFDT combines a GA and a neural fuzzy network into a binary classification tree. This approach also exploits the power of the classification tree. Simulation results show that the GANFDT provides an efficient way of carrying out mixed scheduling in ATM networks.

Modelling and analysis of routing and resource allocation techniques in multi‐service networks

In this paper a novel call level model based on the extension of the classical Erlang multi-rate model for broadband integrated services networks is proposed. We use the model to study routing stra ...

Potential communication services using power line carriers and broadband integrated services digital network

The concept of using the power line in conjunction with the broadband integrated services network (BISDN) for a range of value added service is proposed. The use of the power line in the low voltage distribution network, as a local loop in communications for a range of customer services in the residential and industrial area is detailed. The integration of this local loop residential service into a BISDN network provides the potential for integrating many thousand of homes into a wide area network (WAN) architecture. The potential characteristics of this type of communication architecture are established for efficient transport of data services.

A simulation based approach for network resources dimensioning in video delivery systems

The availability of high-performance networking technologies and processing power allows creation of new multimedia services and applications in broadband integrated services networks. Such new services will be successful only if delivered to end-users at low cost. At present, for wide-area distributed systems, communication has a relevant impact on the overall costs. As a consequence, adequate methodologies for an efficient dimensioning of the network resources need to be devised. Simulation techniques represent a powerful instrument for the analysis and evaluation of real systems. This paper, moving from the definition of mathematical models for VBR video sources, presents the application of a simulation approach to verify the compatibility of the communication load related to a set of video streams with the data transport capability of an existing network architecture for the delivery of video streams, in the case of CBR communication links.

Video aggregation: adapting video traffic for transport over broadband networks by integrating data compression and statistical multiplexing

Future broadband integrated services networks based on the asynchronous transfer mode (ATM) technology are expected to carry information from a large variety of different services and applications. This paper investigates video aggregation, a concept that integrates compression and statistical multiplexing of video information for transport over a communication network. We focus on the transmission of a group of video sessions as a bundle, the practical examples of which include entertainment-video broadcast and video-on-demand (VoD). In this situation, the advantage of constant bit-rate (CBR) transport (which facilitates simple network management and operation) and the advantage of variable bit-rate (VBR) video compression (which yields smoother image quality) can be achieved simultaneously. We show that it is better to integrate compression and statistical multiplexing before the bundle of video traffic enters the network than performing them as independent processes. We present experimental results which indicate the advantages of video aggregation in terms of superior image quality and efficient bandwidth usage.

Study of the impact of MPEG-1 correlations on video-sources statistical multiplexing

Variable bit-rate (VBR) video is expected to become increasingly important with the large scale deployment of broadband-integrated services networks (B-ISDNs). While the modeling of VBR video sources has received significant attention, there is no widely accepted model which lends itself to mathematical analysis. Furthermore, new video compression standards are emerging, such as the MPEG family. A detailed statistical analysis of a long sample of a movie encoded with an MPEG-1 algorithm highlights that traffic generated by an MPEG-1 encoder has both a high degree of burstiness (peak/average ratio greater than five) and a strong long-term correlation (positive correlation lasts for ten/twenty minutes). In this paper, we propose and analyze a Markov model which captures both the burstiness and the temporal dependencies of MPEG traffic. Furthermore, we show that our model is a flexible traffic generator which is suitable for studying statistical multiplexing issues. Specifically, we study both the multiplexing of a VBR video source with low priority traffic and the multiplexing of several VBR video sources. The results obtained show that the long-term correlation significantly affects the tail of the delay distribution even for lightly loaded networks. The presence of a long range dependence in the MPEG traffic significantly reduces the gain in terms of network utilization which can be achieved with statistical multiplexing of i.i.d. sources.

Tree Computation for Reserved Bandwidth Traffic

With the deployment of broadband integrated services networks, multipoint applications are likely to be developed on digital networks. Many, if not all, of these applications will benefit from network support for quality of service requirements, which can be readily provided if the network supports reserved bandwidth multipoint communication channels. In this paper, we discuss the different kinds of applications that may require support for bandwidth reservation, and discuss how a multipoint communication channel can be found for multi point applications. For several applications, finding a multipoint communication channel is a NP-hard problem, and we will present heuristics to solve it under different circumstances. We study these heuristics by means of simulations and attempt to provide theoretical bounds on their performance.

A mathematical model and related problems of optimal management and design in a broadband integrated services network

AbstractThis paper describes a mathematical model for a broadband integrated services network offered traffic of many different types. Performance measures are introduced related to revenue generation and overall grade-of-service, providing criteria for the optimal management of resources. Simple asymptotic expressions are derived for quantities termed the “implied costs”, which measure the effect on performance of changes in parameters that are controllable by network management, or that are subject to variation. These implied costs may be used, both to implement optimal bandwidth allocation polices, and also to indicate which services may share a single facility without adversely affecting performance, and which might require a dedicated facility. Asymptotic results are also used to examine how to make efficient use of capacity that is shared between calls with fluctuating bit-rate requirements.