A Scalable Virtual Circuit Routing Scheme for ATM Networks

High-speed networks, such as ATM networks, are expected to support diverse quality-of-service (QoS) requirements, including real-time QoS. Real-time QoS is required by many applications such as voice and video. To support such service, routing protocols based on the Virtual Circuit (VC) model have been proposed. However, these protocols do not scale well to large networks in terms of storage and communication overhead. In this paper, we present a scalable VC routing protocol. It is based on the recently proposed viewserver hierarchy, where each viewserver maintains a partial view of the network. By querying these viewservers, a source can obtain a merged view that contains a path to the destination. The source then sends a request packet over this path to setup a real-time VC through resource reservations. The request is blocked if the setup fails. We compare our protocol to a simple approach using simulation. Under this simple approach, a source maintains a full view of the network. In addition to the savings in storage, our results indicate that our protocol performs close to or better than the simple approach in terms of VC carried load and blocking probability over a wide range of real-time workload. (Also cross-referenced as UMIACS-TR-94-115

Dynamic bandwidth allocation in ATM networks

Includes bibliographical references.This thesis investigates bandwidth allocation methodologies to transport new emerging bursty traffic types in ATM networks. However, existing ATM traffic management solutions are not readily able to handle the inevitable problem of congestion as result of the bursty traffic from the new emerging services. This research basically addresses bandwidth allocation issues for bursty traffic by proposing and exploring the concept of dynamic bandwidth allocation and comparing it to the traditional static bandwidth allocation schemes

A Survey of Network Optimization Techniques for Traffic Engineering

TCP/IP represents the reference standard for the implementation of interoperable communication networks. Nevertheless, the layering principle at the basis of interoperability severely limits the performance of data communication networks, thus requiring proper configuration and management in order to provide effective management of traffic flows. This paper presents a brief survey related to network optimization using Traffic Engineering algorithms, aiming at providing additional insight to the different alternatives available in the scientific literature

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

Switching techniques in data-acquisition systems for future experiments

An overview of the current state of development of parallel event-building techniques is given, with emphasis of future applications in the high-rate experiments proposed at the Large Hadron Collider (LHC). The paper describes the ain architectural options in parallel event builders, the proposed event-building architectures for LHC experiments, and the use of standard net- working protocols for event building and their limitations. The main issues around the potential use of circuit switching, message switching and packet switching are examined. Results from various laboratory demonstrator systems are presented

An Efficient Scheme for Traffic Management in ATM Networks

A pre-print of "An Efficient Scheme for Traffic Management in ATM Networks". The final publication is available at www.springerlink.comAs ATM network is designed for broad band transmission that is high data rate (25 Mbps to 2.5 Gbps) and supports the transmission of every kind of data, congestion control and delay have been important issues for ATM networks. Data transmission is done in the form of cell (53 bytes) relay. Hence, cell sequence and the error control have to be carried out properly. ATM networks presents difficulties in effectively controlling congestion not found in other types of networks, including frame relay networks. In this paper, we present an efficient methodology for traffic management. The simulation results suggest that the proposed solution is effective for both slow and high data rate transmission.http://link.springer.com/chapter/10.1007%2F978-1-4020-8737-0_9

Wavelength assignment in all-optical networks for mesh topologies

All-Optical Networks employing Dense Wavelength Division Multiplexing (DWDM) are believed to be the next generation networks that can meet the ever-increasing demand for bandwidth of the end users. This thesis presents some new heuristics for wavelength assignment and converter placement in mesh topologies. Our heuristics try to assign the wavelengths in an efficient manner that results in very low blocking probability. We propose novel static and dynamic assignment schemes that outperform the assignments reported in the literature even when converters are used. The proposed on-line scheme called Round-Robin assignment outperforms previously proposed strategies such as first-fit and random assignment schemes. The performance improvement obtained with the proposed static assignments is very significant when compared with the dynamic schemes. We designed and developed a simulator in the C language that supports the 2D mesh topology with DWDM. We ran extensive simulations and compared our heuristics with those reported in the literature. We have examined converter placement in mesh topologies and proposed that placing converters at the center yields better results than uniform placement when dimension order routing is employed. We introduced a new concept called wavelength assignment with second trial that results in extremely low blocking probabilities when compared to schemes based on a single trial. Our proposed schemes are simple to implement and do not add to the cost. Thus we conclude that wavelength assignment plays more significant role in affecting the blocking probability than wavelength converters. We further conclude that static schemes without converters could easily outperform dynamic schemes thus resulting in great savings