Pub Date : 2002-07-01DOI: 10.1109/ISCC.2002.1021743
C. Park, D. Han, Yutae Lee
In this paper, we present a discrete-time finite queueing model with deterministic service times and an MMBBP (Markov Modulated Batch Bernoulli Process) as a bursty input traffic model of IP packets in order to investigate the performance of a DBAS (Dynamic Bandwidth AllocationScheme) in an ATM/IWU (interworking unit). We assume that the segmentation processing time devoted to each cell requires several slot times in the ATM/IWU. In an MMBBP process,the arrivals during a slot time occur as batch Bernoulli processes with the batch size distributions varying according to the phases of a Markov chain. As performance measures, we obtain the packet loss probability and the mean packet delay of an arbitrary packet. We present some numerical results to show the effects of the service time and burstiness of input traffic on the performance of the presented DBAS.
{"title":"Queueing analysis of dynamic bandwidth allocation scheme for IP traffic on ATM networks","authors":"C. Park, D. Han, Yutae Lee","doi":"10.1109/ISCC.2002.1021743","DOIUrl":"https://doi.org/10.1109/ISCC.2002.1021743","url":null,"abstract":"In this paper, we present a discrete-time finite queueing model with deterministic service times and an MMBBP (Markov Modulated Batch Bernoulli Process) as a bursty input traffic model of IP packets in order to investigate the performance of a DBAS (Dynamic Bandwidth AllocationScheme) in an ATM/IWU (interworking unit). We assume that the segmentation processing time devoted to each cell requires several slot times in the ATM/IWU. In an MMBBP process,the arrivals during a slot time occur as batch Bernoulli processes with the batch size distributions varying according to the phases of a Markov chain. As performance measures, we obtain the packet loss probability and the mean packet delay of an arbitrary packet. We present some numerical results to show the effects of the service time and burstiness of input traffic on the performance of the presented DBAS.","PeriodicalId":261743,"journal":{"name":"Proceedings ISCC 2002 Seventh International Symposium on Computers and Communications","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121769162","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-07-01DOI: 10.1109/ISCC.2002.1021651
A. Ciuffoletti
The problem of rollback recovery is traditionally approached using a model oriented to packet delivery. Instead, we introduce a model centered around complex sessions, and we explain why this model is more appropriate. Using this model, we extract a basic coordination scheme that is common to the three distributed activities that compose rollback recovery: checkpointing, rollback and disposal. The basic coordination scheme is refined to describe each of the three activities.
{"title":"Session level rollback recovery","authors":"A. Ciuffoletti","doi":"10.1109/ISCC.2002.1021651","DOIUrl":"https://doi.org/10.1109/ISCC.2002.1021651","url":null,"abstract":"The problem of rollback recovery is traditionally approached using a model oriented to packet delivery. Instead, we introduce a model centered around complex sessions, and we explain why this model is more appropriate. Using this model, we extract a basic coordination scheme that is common to the three distributed activities that compose rollback recovery: checkpointing, rollback and disposal. The basic coordination scheme is refined to describe each of the three activities.","PeriodicalId":261743,"journal":{"name":"Proceedings ISCC 2002 Seventh International Symposium on Computers and Communications","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114289793","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-07-01DOI: 10.1109/ISCC.2002.1021701
L. Mengual, N. Barcia, E. Jiménez, Ernestina Menasalvas Ruiz, J. Setien, J. Yágüez
We present an automatic implementation system of security protocols based in formal description techniques. A sufficiently complete and concise formal specification that has allowed us to define the state machine that corresponds to a security protocol has been designed to achieve our goals. This formal specification makes it possible to incorporate in a flexible way the security mechanisms and functions (random numbers generation, timestamps, symmetric-key encryption, public-key cryptography, etc). Our solution implies the incorporation of an additional security layer LEI (Logical Element of Implementation) in the TCP/IP architecture. This additional layer be able both to interpret and to implement any security protocol from its formal specification. Our system provides an applications programming interface (API) for the development of distributed applications in the Internet like the e-commerce, bank transfers, network management or distribution information services that makes transparent to them the problem of security in the communications.
{"title":"Automatic implementation system of security protocols based on formal description techniques","authors":"L. Mengual, N. Barcia, E. Jiménez, Ernestina Menasalvas Ruiz, J. Setien, J. Yágüez","doi":"10.1109/ISCC.2002.1021701","DOIUrl":"https://doi.org/10.1109/ISCC.2002.1021701","url":null,"abstract":"We present an automatic implementation system of security protocols based in formal description techniques. A sufficiently complete and concise formal specification that has allowed us to define the state machine that corresponds to a security protocol has been designed to achieve our goals. This formal specification makes it possible to incorporate in a flexible way the security mechanisms and functions (random numbers generation, timestamps, symmetric-key encryption, public-key cryptography, etc). Our solution implies the incorporation of an additional security layer LEI (Logical Element of Implementation) in the TCP/IP architecture. This additional layer be able both to interpret and to implement any security protocol from its formal specification. Our system provides an applications programming interface (API) for the development of distributed applications in the Internet like the e-commerce, bank transfers, network management or distribution information services that makes transparent to them the problem of security in the communications.","PeriodicalId":261743,"journal":{"name":"Proceedings ISCC 2002 Seventh International Symposium on Computers and Communications","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130820284","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-07-01DOI: 10.1109/ISCC.2002.1021698
Iara Augustin, A. Yamin, J. Barbosa, C. Geyer
Mobile computing has emerged as a new field, distinct from conventional distributed computing by its focus on mobility and its consequence. The physical and logical mobility needs of applications with new requirements: built-in mobility, adaptability and flexibility. Providing a system architecture that simplifies the task of implementing the mobile applications with adaptive behavior is the objective of the ongoing ISAM project. In order to achieve its goal, ISAM uses, as strategies, an integrated environment that: (a) provides a programming paradigm and its execution environment; (b) treats of adaptation process through multilevel collaborative model, in which both the system and the application contribute for that. We present the ISAM architecture and introduce the relative issues to the treatment of adaptive mobile applications.
{"title":"ISAM, a software architecture for adaptive and distributed mobile applications","authors":"Iara Augustin, A. Yamin, J. Barbosa, C. Geyer","doi":"10.1109/ISCC.2002.1021698","DOIUrl":"https://doi.org/10.1109/ISCC.2002.1021698","url":null,"abstract":"Mobile computing has emerged as a new field, distinct from conventional distributed computing by its focus on mobility and its consequence. The physical and logical mobility needs of applications with new requirements: built-in mobility, adaptability and flexibility. Providing a system architecture that simplifies the task of implementing the mobile applications with adaptive behavior is the objective of the ongoing ISAM project. In order to achieve its goal, ISAM uses, as strategies, an integrated environment that: (a) provides a programming paradigm and its execution environment; (b) treats of adaptation process through multilevel collaborative model, in which both the system and the application contribute for that. We present the ISAM architecture and introduce the relative issues to the treatment of adaptive mobile applications.","PeriodicalId":261743,"journal":{"name":"Proceedings ISCC 2002 Seventh International Symposium on Computers and Communications","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129582811","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-07-01DOI: 10.1109/ISCC.2002.1021671
E. Karami, M. Shiva, M. Khansari
In this paper, an efficient method for multiuser detection of CDMA signal is proposed, that provides soft output with remaining noise distribution close to the Gaussian. Therefore the proposed algorithm is efficient for both coded and uncoded signals. This algorithm is simulated for BPSK signals with random spreading. The performance of the receiver is analyzed in terms of BER and spectral efficiency of each user for full load and overload conditions. Simulation results show that performance of the proposed algorithm is very close to the optimum receiver for both coded and uncoded user signals and also that it outperforms the previously proposed algorithms.
{"title":"An efficient multiuser detection algorithm for CDMA signals","authors":"E. Karami, M. Shiva, M. Khansari","doi":"10.1109/ISCC.2002.1021671","DOIUrl":"https://doi.org/10.1109/ISCC.2002.1021671","url":null,"abstract":"In this paper, an efficient method for multiuser detection of CDMA signal is proposed, that provides soft output with remaining noise distribution close to the Gaussian. Therefore the proposed algorithm is efficient for both coded and uncoded signals. This algorithm is simulated for BPSK signals with random spreading. The performance of the receiver is analyzed in terms of BER and spectral efficiency of each user for full load and overload conditions. Simulation results show that performance of the proposed algorithm is very close to the optimum receiver for both coded and uncoded user signals and also that it outperforms the previously proposed algorithms.","PeriodicalId":261743,"journal":{"name":"Proceedings ISCC 2002 Seventh International Symposium on Computers and Communications","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123044647","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-07-01DOI: 10.1109/ISCC.2002.1021710
Dhananjay Lal, Rahul Gupta, D. Agrawal
The use of directional antennas in cellular wireless networks offers many advantages such as range extension, reduced interference for signal detection and improved throughput. MAC protocols using directional antennas for wireless ad hoc networks that are based on and similar to IEEE 802.11 type WLANs have been proposed. We explore 'multiplexing in space' with directional antennas to enhance the total throughput at a bottleneck node in the network. We develop an access protocol for antenna systems that can transmit to multiple destinations simultaneously (and possibly receive from multiple sources as well). Some issues enabling multiple access in space for ad hoc network nodes are discussed. Our simulation results show that the current 802.11 MAC scheme using omnidirectional antennas for channel access fairs very poorly as the bandwidth demand increases. In contrast, we see substantial improvement when spatial multiplexing is employed.
{"title":"Throughput enhancement in wireless ad hoc networks with spatial channels a MAC layer perspective","authors":"Dhananjay Lal, Rahul Gupta, D. Agrawal","doi":"10.1109/ISCC.2002.1021710","DOIUrl":"https://doi.org/10.1109/ISCC.2002.1021710","url":null,"abstract":"The use of directional antennas in cellular wireless networks offers many advantages such as range extension, reduced interference for signal detection and improved throughput. MAC protocols using directional antennas for wireless ad hoc networks that are based on and similar to IEEE 802.11 type WLANs have been proposed. We explore 'multiplexing in space' with directional antennas to enhance the total throughput at a bottleneck node in the network. We develop an access protocol for antenna systems that can transmit to multiple destinations simultaneously (and possibly receive from multiple sources as well). Some issues enabling multiple access in space for ad hoc network nodes are discussed. Our simulation results show that the current 802.11 MAC scheme using omnidirectional antennas for channel access fairs very poorly as the bandwidth demand increases. In contrast, we see substantial improvement when spatial multiplexing is employed.","PeriodicalId":261743,"journal":{"name":"Proceedings ISCC 2002 Seventh International Symposium on Computers and Communications","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132603946","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-07-01DOI: 10.1109/ISCC.2002.1021670
S. Porcarelli, F. Giandomenico, A. Bondavalli
With reference to the General Packet Radio Service (GPRS), an extension of the Global System for Mobile Communication (GSM) addressing packet-oriented traffic, this paper contributes to the analysis of the service accomplishment level perceived by GPRS users. The proposed modeling approach builds separately the GPRS and user models; the focus is on the GPRS random access procedure on the one side, and different classes of user behavior on the other side. The overall model is composed of the basic submodels. Quantitative analysis, performed using a simulation approach, is carried out, showing the impact of users' characteristics and network load on identified indicators expressing the QoS as perceived by users.
{"title":"Analyzing quality of service of GPRS network systems from a user's perspective","authors":"S. Porcarelli, F. Giandomenico, A. Bondavalli","doi":"10.1109/ISCC.2002.1021670","DOIUrl":"https://doi.org/10.1109/ISCC.2002.1021670","url":null,"abstract":"With reference to the General Packet Radio Service (GPRS), an extension of the Global System for Mobile Communication (GSM) addressing packet-oriented traffic, this paper contributes to the analysis of the service accomplishment level perceived by GPRS users. The proposed modeling approach builds separately the GPRS and user models; the focus is on the GPRS random access procedure on the one side, and different classes of user behavior on the other side. The overall model is composed of the basic submodels. Quantitative analysis, performed using a simulation approach, is carried out, showing the impact of users' characteristics and network load on identified indicators expressing the QoS as perceived by users.","PeriodicalId":261743,"journal":{"name":"Proceedings ISCC 2002 Seventh International Symposium on Computers and Communications","volume":"107 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131474471","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-07-01DOI: 10.1109/ISCC.2002.1021758
P. Bellavista, Antonio Corradi, Silvia Vecchi
The convergence of mobile telecommunications and the Internet global system forces us to reconsider traditional client/server solutions for network and systems management. The paper claims that accounting in the mobility-enabled Internet requires support infrastructures hosted in the fixed network. These infrastructures should monitor, control and register resource consumption locally within the domains where users/terminals dynamically move to, without requiring continuous connectivity with remote and centralized accounting home managers. In addition, the paper shows that the mobile agent (MA) technology is suitable to overcome the limits of traditional accounting solutions in several mobility-enabled usage scenarios. MA can maximize locality in accessing monitoring data, can enable accounting even in case of temporary disconnection, can install new monitoring/control behavior dynamically, and can support session-dependent solutions. The paper finally presents the design and implementation of the MA-based Middleware for Mobility Accounting Management (MAM/sup 2/), together with some use cases showing the advantages of the MA adoption.
{"title":"Mobile agent solutions for accounting management in mobile computing","authors":"P. Bellavista, Antonio Corradi, Silvia Vecchi","doi":"10.1109/ISCC.2002.1021758","DOIUrl":"https://doi.org/10.1109/ISCC.2002.1021758","url":null,"abstract":"The convergence of mobile telecommunications and the Internet global system forces us to reconsider traditional client/server solutions for network and systems management. The paper claims that accounting in the mobility-enabled Internet requires support infrastructures hosted in the fixed network. These infrastructures should monitor, control and register resource consumption locally within the domains where users/terminals dynamically move to, without requiring continuous connectivity with remote and centralized accounting home managers. In addition, the paper shows that the mobile agent (MA) technology is suitable to overcome the limits of traditional accounting solutions in several mobility-enabled usage scenarios. MA can maximize locality in accessing monitoring data, can enable accounting even in case of temporary disconnection, can install new monitoring/control behavior dynamically, and can support session-dependent solutions. The paper finally presents the design and implementation of the MA-based Middleware for Mobility Accounting Management (MAM/sup 2/), together with some use cases showing the advantages of the MA adoption.","PeriodicalId":261743,"journal":{"name":"Proceedings ISCC 2002 Seventh International Symposium on Computers and Communications","volume":"245 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131880969","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-07-01DOI: 10.1109/ISCC.2002.1021793
Gergely Seres, Árpád Szlávik, J. Zátonyi, J. Bíró
This paper identifies the requirements placed against a resource manager function for use in QoS-enabled IP networks. The structure of the Internet and the composition of the services motivate the development of on-line resource brokers that can make admission decisions in real time, based on the best up-to-date information available on the state of the network. The difficulties with traffic models and traffic characterisation stimulate the use of measurement-based techniques that bypass the modelling step and provide the resource requirements of the traffic directly. The paper introduces a novel method for the computation of the bandwidth requirement of Internet traffic flows using the many sources asymptotics. The estimator method significantly reduces the computational complexity of the calculations, allowing the real-time operation of the algorithm even in a measurement-based environment. The method delivers bandwidth-type quantity, the format preferred by Internet control applications. The savings arising from the reduced computational complexity compared to existing methods are demonstrated in a numerical example.
{"title":"Alternative admission rules based on the many sources asymptotics","authors":"Gergely Seres, Árpád Szlávik, J. Zátonyi, J. Bíró","doi":"10.1109/ISCC.2002.1021793","DOIUrl":"https://doi.org/10.1109/ISCC.2002.1021793","url":null,"abstract":"This paper identifies the requirements placed against a resource manager function for use in QoS-enabled IP networks. The structure of the Internet and the composition of the services motivate the development of on-line resource brokers that can make admission decisions in real time, based on the best up-to-date information available on the state of the network. The difficulties with traffic models and traffic characterisation stimulate the use of measurement-based techniques that bypass the modelling step and provide the resource requirements of the traffic directly. The paper introduces a novel method for the computation of the bandwidth requirement of Internet traffic flows using the many sources asymptotics. The estimator method significantly reduces the computational complexity of the calculations, allowing the real-time operation of the algorithm even in a measurement-based environment. The method delivers bandwidth-type quantity, the format preferred by Internet control applications. The savings arising from the reduced computational complexity compared to existing methods are demonstrated in a numerical example.","PeriodicalId":261743,"journal":{"name":"Proceedings ISCC 2002 Seventh International Symposium on Computers and Communications","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133980271","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-07-01DOI: 10.1109/ISCC.2002.1021667
Ashraf Awad, M. W. McKinnon, Raghupathy Sivakumar
We present an algorithm to estimate analytically the frame goodput of a correlated MPEG-2 video source that traverses a first network node's buffer; where frame goodput is defined as the ratio of the number of cells in completely and correctly transmitted frames through the buffer to the total number of cells arriving at the buffer. The effect on the frame goodput of changing the output-to-input line speeds is also investigated. By using this algorithm, a buffer that is three times the maximum frame size is seen to yield loss probability of 10/sup -6/ at a normalized output line rate of 0.28 for a load of 20%. A maximum simulation error margin of /spl plusmn/30% for values of the order of 10/sup -5/ with a 98% confidence was achieved.
{"title":"Goodput estimation for an access node buffer carrying correlated video traffic","authors":"Ashraf Awad, M. W. McKinnon, Raghupathy Sivakumar","doi":"10.1109/ISCC.2002.1021667","DOIUrl":"https://doi.org/10.1109/ISCC.2002.1021667","url":null,"abstract":"We present an algorithm to estimate analytically the frame goodput of a correlated MPEG-2 video source that traverses a first network node's buffer; where frame goodput is defined as the ratio of the number of cells in completely and correctly transmitted frames through the buffer to the total number of cells arriving at the buffer. The effect on the frame goodput of changing the output-to-input line speeds is also investigated. By using this algorithm, a buffer that is three times the maximum frame size is seen to yield loss probability of 10/sup -6/ at a normalized output line rate of 0.28 for a load of 20%. A maximum simulation error margin of /spl plusmn/30% for values of the order of 10/sup -5/ with a 98% confidence was achieved.","PeriodicalId":261743,"journal":{"name":"Proceedings ISCC 2002 Seventh International Symposium on Computers and Communications","volume":"93 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132909211","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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