By Topic

Computers and Communications, 2000. Proceedings. ISCC 2000. Fifth IEEE Symposium on

Date 3-6 July 2000

Filter Results

Displaying Results 1 - 25 of 125
  • ISCC 2000 Fifth IEEE Symposium on Computers and Communications [front matter]

    Publication Year: 2000 , Page(s): i - xvi
    Save to Project icon | Request Permissions | PDF file iconPDF (695 KB)  
    Freely Available from IEEE
  • Author index

    Publication Year: 2000 , Page(s): 806 - 808
    Save to Project icon | Request Permissions | PDF file iconPDF (180 KB)  
    Freely Available from IEEE
  • Differentiated services and integrated services use of MPLS

    Publication Year: 2000 , Page(s): 194 - 199
    Cited by:  Papers (4)  |  Patents (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (520 KB)  

    All the new emerging QoS service architectures are motivated by the desire to improve the overall performance of IP networks. Integrated services (Intserv), differentiated services (Diffserv), MultiProtocol Label Switching (MPLS) and constraint-based routing are all technologies starting to coexist together in today's Internet to provide means for the delivery of end-to-end QoS to applications over heterogeneous networks. We propose DRUM (Diffserv and RSVP/intserv Use of MPLS), an architecture that delivers end-to-end service guarantees for both Diffserv and Intserv networks, where part of the underlying technology used for IP transport is MPLS using Diffserv-like mechanisms for QoS provision. We also show how traffic engineering can ameliorate service differentiation, and illustrate how interoperability can be achieved between DRUM and neighboring Diffserv and Intserv networks View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • FATIMA: a firewall-aware transparent Internet mobility architecture

    Publication Year: 2000 , Page(s): 172 - 179
    Cited by:  Papers (3)  |  Patents (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (692 KB)  

    Ubiquitous communication will be one of the paradigms for the next decades. The use of the Internet in such applications demands for a highly reliable and secure system, especially when used in non-academical environments like remote offices, e-commerce, or traffic telematics. Today's Internet, even with the mobility extension Mobile IP, has not been designed with private addresses, firewalls, network address translation quality of service etc. in mind. Several optimisations already exist-however security is often neglected. This paper proposes the firewall-aware transparent Internet mobility architecture FATIMA, which integrates security functionality but is transparent to existing Mobile IP implementations. All security critical functions are concentrated in a firewall, all control messages are authenticated, and micro-mobility is supported. Corporate networks with private addresses are supported seamlessly, and further extensions allow for the use of dynamic home addresses and quality of service support View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Iterative decoding of product codes composed of extended Hamming codes

    Publication Year: 2000 , Page(s): 732 - 737
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (436 KB)  

    Iterative decoding of product codes that uses a soft-in/soft-out decoder based on the Chase algorithm was introduced by R. Pyndiah et al. (see Proc. IEEE GLOBECOM, vol.1/3, p.339-43, 1994). This decoding scheme is quite similar to turbo codes, but makes possible the implementation of the decoder with low complexity while providing acceptable performance. In this paper for the product codes composed of extended Hamming codes, we propose a reduction scheme of test patterns in the Chase algorithm, which can reduce the decoding complexity without performance degradation. Also, we propose a simple, but efficient assignment scheme of artificial extrinsic information to the symbols for which we cannot get reliabilities by the decoding procedure. The simulation results for the proposed schemes are shown and compared with the asymptotic performances that can be calculated by the weight distribution of product codes and the union bound on the BER performances View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Security requirements for management systems using mobile agents

    Publication Year: 2000 , Page(s): 160 - 165
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (660 KB)  

    Flexible and distributed management systems based on mobile agents have certain advantages over centralized and static management architectures. However, security plays a decisive role in terms of acceptance and applicability of mobile agents. In this paper we analyze the threats and attacks against mobile agent systems used for management purposes. Therefore, general models of mobile agent based management systems are developed. Based on a risk analysis of these models we derive security requirements. In order to satisfy these requirements components and services are identified and integrated in a comprehensive security architecture View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Analyses of MPEG-4 video streams processing in computer clusters based on multihop ATM networks

    Publication Year: 2000 , Page(s): 308 - 313
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (484 KB)  

    The introduction of the MPEG-4 standard for interactive digital video necessitates investigations of the properties of MPEG-4 video streams and their processing and transport in distributed systems. Of special importance are the issues affecting MPEG-4 video applications, such as the functionality of network software layers and their impact on the overall quality of service (QoS). In this paper we present an analysis, based on simulation modeling, of the processing and transport of MPEG-4 video in computer clusters connected with multihop ATM networks. Through simulation experiments we obtain results for the QoS parameters (transfer delay, jitter, and the loss rate of cells), average buffer occupancy in the ATM multiplexers along the path of the video streams, and the influence of the AAL protocol layers on the performance of the transfer View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Call admission control for multimedia services in mobile cellular networks: a Markov decision approach

    Publication Year: 2000 , Page(s): 594 - 599
    Cited by:  Papers (18)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (376 KB)  

    There is a growing interest in deploying multimedia services in mobile cellular networks. Call admission control (CAC) is a key factor in quality of service (QoS) provisioning for these services. We propose a CAC which maximizes the revenue by determining the call admission decisions for each state. A semi-Markov decision process is employed to model the cellular system. Also, the QoS requirement such as the handoff dropping probability is taken into consideration. Simulations reveal that our CAC outperforms the upper limit CAC while satisfying the QoS requirements View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • An admission control algorithm for providing quality-of-service guarantee for individual connection in a video-on-demand system

    Publication Year: 2000 , Page(s): 456 - 461
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (452 KB)  

    We consider a theoretical framework for performing admission control in a video-on-demand (VOD) system. Unlike previous work on the admission control on a VOD system guaranteed quality-of-service (QoS) on the aggregated traffic, our admission control algorithm can guarantee the QoS requirements of individual connections. The QoS requirements we consider are the individual connection's bandwidth and the individual connection's packet dropping-rate. These two QoS requirements are specified by users and our admission control algorithm decides whether to admit a new request or not View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • On multiple traffic type integration over wireless TDMA channels

    Publication Year: 2000 , Page(s): 621 - 627
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (556 KB)  

    A new medium access control (MAC) protocol for mobile wireless communications is presented and investigated. We explore, via an extensive simulation study, the performance of the protocol when integrating voice, video and data packet traffic over a wireless channel of high capacity. Depending on the number of video users admitted into the system, our protocol varies: (a) the request bandwidth dedicated to resolving the voice users contention, and (b) the probability with which the base station grants information slots to voice users, in order to preserve full priority for video traffic. We evaluate the voice and video packet dropping probabilities for various voice and video load conditions, and the average data message delays. As proven by the comparison with a previously introduced efficient MAC scheme (DPRMA), when integrating voice and video traffic our scheme obtains higher voice capacity and aggregate channel throughput. When integrating all three traffic types, our scheme achieves high aggregate channel throughput in all cases of traffic load View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Managing services in distributed systems by integrating trading and load balancing

    Publication Year: 2000 , Page(s): 641 - 646
    Cited by:  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (556 KB)  

    With a changing structure of networks and application systems due to the requirements of decentralised enterprises and open service markets, distributed systems with rapidly increasing complexity are evolving. New concepts for an efficient management of such systems have to be developed. Focusing on the service level, examples for existing concepts are trading to find services in a distributed environment, and load balancing to avoid performance bottlenecks in service provision. This paper discusses the integration of a load balancer into a trader to adapt the allocation of client requests to suitable servers due to the current system usage, and thus to improve the quality of the services in terms of performance. The approach used is independent of the servers' characteristics, because for the servers involved, no provision of additional service properties to cover load aspects is necessary. Furthermore, it is flexible to enhance, because the concept of load used can be varied without modification of trader or load balancer View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Bandwidth sensitive content transformation in pervasive computing

    Publication Year: 2000 , Page(s): 14 - 19
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (484 KB)  

    In pervasive Internet access, the quality of presentation often needs to be adjusted according to the instantaneous network bandwidth and the hardware capability of the user's device. Current Web transformation mechanisms, being unable to adapt dynamically to the available network bandwidth and data requirement, result in uniform loss of quality, and incur additional processing overhead for every user. Hence, it is important to estimate the network conditions of each individual user dynamically, in order to perform appropriate transformation on the Web content for different users to suit their constraints. However, the WWW is a dynamic and diverse environment with great heterogeneity among its users, servers, networks, and data. This makes it difficult for us to discover the diverse network constraints of different users. The authors propose a bandwidth sensitive content transformation proxy solution to deliver the best-fit presentation to Web surfers. Transformation to Web content will be done according to the amount of latency saved, the availability of the current network bandwidth, and the workload of the servers due to transformation. To illustrate its potential, automatic Web data compression is used as an example on how adaptive content transformation will be performed and optimized View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Evolution of operation support systems in public data networks

    Publication Year: 2000 , Page(s): 72 - 77
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (340 KB)  

    Operation support systems (OSS) facilitate the development, deployment and maintenance or high-quality network-based services at a reasonable cost. This paper reviews the trends, particularly the customers' needs to manage their own data networks, and their effects on the architecture of OSS of public data networks View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Location registration and paging in mobile satellite systems

    Publication Year: 2000 , Page(s): 232 - 237
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (472 KB)  

    Mobile satellite systems are a crucial component of the future global telecommunications infrastructure. An important aspect of the future system is to manage the location of both users and satellites. This paper presents a strategy for location registration (update) and paging in low Earth orbit (LEO) mobile satellite systems. First, we discuss the tradeoff that exists between four proposed satellite location area designations. Then we introduce a scheme that selects a simple location area design and uses a hierarchical database architecture to reduce the location management signaling delay. The performance of the scheme is analyzed in terms of the paging bandwidth and the location update signaling delay. Finally, we present the numerical results for several planned systems, such as GlobalStar, ICO, and IRIDIUM View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A performance system based on the balanced scorecard approach for measuring performance in a business environment

    Publication Year: 2000 , Page(s): 220 - 224
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (388 KB)  

    Businesses today are succeeding and growing by better understanding their customers' needs and aligning their operational processes that effectively service the customers. They are creating work processes and methods that are well linked and well operated. Utilizing a system of performance measures, they also are focusing on non-financial indicators to take advantage of key internal and external opportunities and responding to them swiftly. Beyond incremental gains, they are realizing dramatic gains in the critical areas affecting customer satisfaction, cycle time, cost, responsiveness and quality. This paper provides the reader with the architectural design and a detailed technical specification of the performance system. The proposed platform enables the implementation of performance systems on top of preexisting, already running, information and workflow systems that support the daily business of the enterprise. The performance system is a Web-based application that covers the functions needed to create a performance data mall, measurement tools and associated visual interfaces. It is developed using the Microsoft Active Server Pages technology. The data mall is implemented in an MS Set Server 7.0, which is accessed through Active Data Objects (ADO) 2.1 View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Distributed algorithms and architectures for optical flow switching in WDM networks

    Publication Year: 2000 , Page(s): 134 - 139
    Cited by:  Papers (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (488 KB)  

    This paper is about the design and quantitative analysis of distributed approaches for optical flow switching (using dynamic lightpath setup) in a wide area WDM backbone network. The major contribution of this work is to design realistic integrated approaches for flow routing, wavelength assignment, and connection setup in a truly distributed setting, and assess the relative performance of these on a nationwide wide area network (WAN) backbone. A simulation model is used which models timing, wavelength, and fiber constraints. Results are presented in terms of backbone utilization for a given blocking probability of optical flows View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Hierarchical performance modeling for distributed system architectures

    Publication Year: 2000 , Page(s): 659 - 664
    Cited by:  Papers (2)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (476 KB)  

    Performance modeling and evaluation techniques are essential when designing and implementing distributed software systems. Constructing performance models for such systems can require significant effort. This paper presents Hierarchical Performance Modeling as a technique to model performance for different layers of abstraction. Once the system architecture and software functionality have been specified, this model supports performance model generation for the evaluation and analysis of computation delays of software processes, communication delays of distributed software architectures, and hardware platform alternatives. A simplified example is presented to illustrate the concepts of the Hierarchical Performance Model View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Producing standards for communication systems-the impact of the individual

    Publication Year: 2000 , Page(s): 268 - 273
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (484 KB)  

    The paper attempts to contribute to a better understanding of how standards actually emerge, by having a closer look at what is going on inside standards setting committees. It discusses the results of a study of long-standing members of committees in charge of standardising electronic messaging systems, from ISO, ITU, and the IETF. The author looks at who they are, where they come from, which roles they assume during the process, how they perceive this process, and what they feel actually influences its final outcome, i.e. the standard View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Striping scheme for wireless communication systems

    Publication Year: 2000 , Page(s): 520 - 525
    Cited by:  Papers (2)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (436 KB)  

    Using a communication system composed of multiple links, with different characteristics and throughputs, not only increases the global transmission throughput but also considerably improves the reliability of the system. However, to be fully efficient such a system requires particular schemes, called striping schemes, to split traffic over the links. The allocation of the successive packets towards one or other link can heavily affect delays before retransmission of any lost packets, and finally modifies the final throughput obtained. This paper considers wireless communications with particularly unreliable performances. It proposes an analysis of the effects of possible packets striping methods and presents some simulation results which allow some parameters of our striping algorithm to be optimized. The delays obtained with our method is then compared to those obtained with other schemes View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Experiences in programming a traffic shaper

    Publication Year: 2000 , Page(s): 470 - 476
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (424 KB)  

    A traffic shaper regulates the transmission of packets according to a pre-determined rate, seemingly a straightforward program. A frequently used technique to achieve the prescribed rate is to interleave packet transmissions with sleeps, an operating system function. If the sleep duration cannot be accurately controlled, it can adversely impact the performance of the traffic shaper. We describe the problem caused by an inaccurate sleep, various algorithms for compensating for the inaccuracy, and how to accommodate intermittent data arrival streams at the same time. The objective is to produce an accurate, yet simple, robust, and efficient traffic shaper View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • General construction of periodic complete complementary codes composed of expanded modulatable orthogonal sequences

    Publication Year: 2000 , Page(s): 738 - 743
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (304 KB)  

    In this paper, we propose a construction of periodic complete complementary codes composed of the expanded modulatable orthogonal sequences. Because the number of the expanded modulatable orthogonal sequences of period N2 is infinite, the number of the periodic complete complementary codes of period N2 is also infinite. It is already proved that the proposed sequences are periodic complete complementary codes. In the meantime Suehiro (1998) has proposed a signal design method for approximately synchronized CDMA systems without co-channel interference. In this signal design method, we can assign the proposed periodic complete complementary codes as code words to each user so that the information transmission rate is increased View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A simple XOR-based technique for distributing group key in secure multicasting

    Publication Year: 2000 , Page(s): 166 - 171
    Cited by:  Papers (1)  |  Patents (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (508 KB)  

    One approach to multicast group security is to have a group key shared by every group member. In this paper, we are interested in group key distribution and management. A new simple technique is introduced for key distribution to a large group based on the hierarchical key tree. The new technique uses bit XOR operation between keys to reduce the computation effort, and uses random byte patterns (BPs) to distribute the key material in the multicast message. The new technique has symmetric procedures for message construction by a key distribution center (KDC) when a member joins or leaves the group, which allows the generation of one rekey message that incorporates multiple delays of both joins and leaves. In addition to the substantial decrease in the computation effort, our technique decreases the required group member storage. Finally, a novel model for the key tree in a distributed KDC is introduced. The new model allows sending the rekey message by one KDC to the whole group and other peer KDCs without any increase in the delay or the number of sent messages. This is achieved by building and replicating an additional KDC key tree View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Bandwidth adaptation of audio streams for mobile hosts

    Publication Year: 2000 , Page(s): 314 - 319
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (512 KB)  

    Wireless technologies, characterized by their dynamically varying bandwidth and signal quality, provide a harsh environment for audio and video applications. Restricted bandwidth leads to losses and delays which significantly reduce the quality of playback at the receiver. In this paper we present a coding and transport technique which allows the bandwidth used by real-time multicast audio streams to adapt to current network conditions. The hierarchical audio for mobile hosts (HIERAM) coding scheme divides an audio stream into stream components representing multiple levels of audio resolution. A receiver may select the number of components she wishes to receive, where a larger number of streams provides higher resolution at the cost of higher bandwidth usage. We have implemented this coding and transport mechanism and present results showing its advantages View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Connection admission control in micro-cellular multi-service mobile networks

    Publication Year: 2000 , Page(s): 600 - 606
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (500 KB)  

    This paper investigates the use of fixed bandwidth reservation for multi-service mobile networks. In particular it extends previous fixed multi-service network results to the mobile scenario and presents analytical and simulation results for new and handover call blocking probabilities. It also investigates the performance sensitivity to different traffic load ratios as well as the cell dwell time distribution View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Association of uplink power control and base station assignment in cellular CDMA systems

    Publication Year: 2000 , Page(s): 705 - 710
    Cited by:  Papers (2)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (552 KB)  

    In a wireless CDMA network a mobile is classically connected to the base station with the best received power level (R×L). The association (or the integration) of base station assignment with power control allows a given network to have better achievable performance. We investigate the association of base station assignment and power control in order to study the best achievable signal-to-interference ratio (SIR) behaviour. The existence of a feasible solution to the quality constraints problem, along with the choice of the base station assignment in order to have the minimal sum of transmitted powers, are discussed. This is done for a unique SIR target and for a multi-target environment. We also address two problems: the base station assignment as a function of network quality targets and best achievable performance which is represented by the highest achievable SIR for every possible BS assignment vector. This last value is computed with less computations than when it is directly calculated. Simulations show that appropriate base station assignment may give interesting capacity gains, especially for non-uniform distributions View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.