An Analysis of flow-based routing

Since their development in the early 1970\u27s, the underlying function of IP routers has not changed - they still support a best effort delivery method in order to pass frames from source to destination. With the advent of newer, bandwidth intensive Internet-based services and applications, such as video conferencing and telemedicine, many individuals wonder if the current approach to routing is the most practical. The Internet needs to provide quality of service ( QoS ) as predictably as conventional circuit switching networks. Although some QoS capabilities in an isolated environment have been demonstrated, providing end-to-end QoS at a large scale across the Internet remains an unsolved problem [1]. The alternative to the traditional method of IP routing is a concept known as flow-based routing, whereas traffic is sent across the network as part of a common flow, rather than individually inspecting each packet. As part of this thesis, the differences between flow-based routing and the current standard of IP routing will be investigated. There are many benefits to be had from routing based on flows, for both routers and applications. Some research has already been done on specific aspects of flow-based routing, but because the concept is so cutting-edge, resources are scarce. This study delves into the benefits and obstacles of flow-based routing, and analyzes characteristics such as practicality and security, along with the benefits of this model

Design issues in quality of service routing

The range of applications and services which can be successfully deployed in packet-switched networks such as the Internet is limited when the network does nor provide Quality of Service (QoS). This is the typical situation in today's Internet. A key aspect in providing QoS support is the requirement for an optimised and intelligent mapping of customer traffic flows onto a physical network topology. The problem of selecting such paths is the task of QoS routing QoS routing algorithms are intrinsically complex and need careful study before being implemented in real networks. Our aim is to address some of the challenges present m the deployment of QoS routing methods. This thesis considers a number of practical limitations of existing QoS routing algorithms and presents solutions to the problems identified. Many QoS routing algorithms are inherently unstable and induce traffic fluctuations in the network. We describe two new routing algorithms which address this problem The first method - ALCFRA (Adaptive Link Cost Function Routing Algorithm) - can be used in networks with sparse connectivity, while the second algorithm - CAR (Connectivity Aware Routing) - is designed to work well in other network topologies. We also describe how to ensure co-operative interaction of the routing algorithms in multiple domains when hierarchial routing is used and also present a solution to the problems of how to provide QoS support m a network where not all nodes are QoS-aware. Our solutions are supported by extensive simulations over a wide range of network topologies and their performance is compared to existing algorithms. It is shown that our solutions advance the state of the art in QoS routing and facilitate the deployment of QoS support in tomorrow's Internet

QoS SOLUTIONS FORVIDEOCONFERENCING

This project is intended to gain knowledge and apply the theory leamt about the need of QoS in videoconferencing and the various options available. Today's conferencing applications are now IP friendly, it can run on either dedicated lines (like ISDN or telephone lines) or IP networks. However, as most network administrators know, conferencingapplications can wreak havoc on unprepared corporate networks. The key to successfully deploying conferencing applications is the activation of Quality of Service (QoS). QoS refers to a network's ability to reliably and consistently provide a certain level of throughput and performance. QoS for conferencing typically involves network availability, bandwidth, end-to-end delay, jitter, and packet loss. Simply stated, if the network doesn't conform to the minimum requirements in any of these areas, the conferences are doomed to fail. QoS can be achieved in a variety of ways, including over-provisioning (deploying additional bandwidth), data prioritization, and the use of QoS-enabled overlay or converged networks. Organizations have two main options for deploying QoS within their organizations; convergence or overlay. Convergence requires the use of QoS-capable WAN links throughout the organization. In many cases, this requires a fork-lift upgrade and migration of all network resources, which can place convergence out of reach of many cost-sensitive organizations. On the other hand, overlay networks allow a step-by-step migration from a non-QoS to a QoS network without the high cost and inherent risk of major network reconfigurations. In this way, overlay networks are a first step toward convergenc

IP and ATM integration: A New paradigm in multi-service internetworking

ATM is a widespread technology adopted by many to support advanced data communication, in particular efficient Internet services provision. The expected challenges of multimedia communication together with the increasing massive utilization of IP-based applications urgently require redesign of networking solutions in terms of both new functionalities and enhanced performance. However, the networking context is affected by so many changes, and to some extent chaotic growth, that any approach based on a structured and complex top-down architecture is unlikely to be applicable. Instead, an approach based on finding out the best match between realistic service requirements and the pragmatic, intelligent use of technical opportunities made available by the product market seems more appropriate. By following this approach, innovations and improvements can be introduced at different times, not necessarily complying with each other according to a coherent overall design. With the aim of pursuing feasible innovations in the different networking aspects, we look at both IP and ATM internetworking in order to investigating a few of the most crucial topics/ issues related to the IP and ATM integration perspective. This research would also address various means of internetworking the Internet Protocol (IP) and Asynchronous Transfer Mode (ATM) with an objective of identifying the best possible means of delivering Quality of Service (QoS) requirements for multi-service applications, exploiting the meritorious features that IP and ATM have to offer. Although IP and ATM often have been viewed as competitors, their complementary strengths and limitations from a natural alliance that combines the best aspects of both the technologies. For instance, one limitation of ATM networks has been the relatively large gap between the speed of the network paths and the control operations needed to configure those data paths to meet changing user needs. IP\u27s greatest strength, on the other hand, is the inherent flexibility and its capacity to adapt rapidly to changing conditions. These complementary strengths and limitations make it natural to combine IP with ATM to obtain the best that each has to offer. Over time many models and architectures have evolved for IP/ATM internetworking and they have impacted the fundamental thinking in internetworking IP and ATM. These technologies, architectures, models and implementations will be reviewed in greater detail in addressing possible issues in integrating these architectures s in a multi-service, enterprise network. The objective being to make recommendations as to the best means of interworking the two in exploiting the salient features of one another to provide a faster, reliable, scalable, robust, QoS aware network in the most economical manner. How IP will be carried over ATM when a commercial worldwide ATM network is deployed is not addressed and the details of such a network still remain in a state of flux to specify anything concrete. Our research findings culminated with a strong recommendation that the best model to adopt, in light of the impending integrated service requirements of future multi-service environments, is an ATM core with IP at the edges to realize the best of both technologies in delivering QoS guarantees in a seamless manner to any node in the enterprise

IP and ATM - current evolution for integrated services

Current and future applications make use of different technologies as voice, data, and video. Consequently network technologies need to support them. For many years, the ATM based Broadband-ISDN has generally been regarded as the ultimate networking technology, which can integrate voice, data, and video services. With the recent tremendous growth of the Internet and the reluctant deployment of public ATM networks, the future development of ATM seems to be less clear than it used to be. In the past IP provided (and was though to provide) only best effort services, thus, despite its world wide diffution, was not considered as a network solution for multimedia application. Currently many of the IETF working groups work on areas related to integrated services, and IP is also proposing itself as networking technology for supporting voice, data, and video services. This paper give a technical overview on the competing integrated services network solutions, such as IP, ATM and the different available and emerging technologies on how to run IP over ATM, and tries to identify their potential and shortcomings

Dynamic bandwidth allocation in multi-class IP networks using utility functions.

PhDAbstact not availableFujitsu Telecommunications Europe Lt

IP and ATM - a position paper

This paper gives a technical overview of different networking technologies, such as the Internet, ATM. It describes different approaches of how to run IP on top of an ATM network, and assesses their potential to be used as an integrated services network

Quality-of-service management in IP networks

Quality of Service (QoS) in Internet Protocol (IF) Networks has been the subject of active research over the past two decades. Integrated Services (IntServ) and Differentiated Services (DiffServ) QoS architectures have emerged as proposed standards for resource allocation in IF Networks. These two QoS architectures support the need for multiple traffic queuing systems to allow for resource partitioning for heterogeneous applications making use of the networks. There have been a number of specifications or proposals for the number of traffic queuing classes (Class of Service (CoS)) that will support integrated services in IF Networks, but none has provided verification in the form of analytical or empirical investigation to prove that its specification or proposal will be optimum. Despite the existence of the two standard QoS architectures and the large volume of research work that has been carried out on IF QoS, its deployment still remains elusive in the Internet. This is not unconnected with the complexities associated with some aspects of the standard QoS architectures. [Continues.