Current Search: Packet switching Data transmission (x)
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- Title
- Missing speech packet reconstruction based on the short-time energy and the zero-crossings.
- Creator
- Castelluccia, Claude., Florida Atlantic University, Erdol, Nurgun
- Abstract/Description
-
A waveform substitution technique using interpolation based on such slow varying parameters of speech as short-time energy and average zero-crossing rate is developed for a packetized speech communication system. The system uses 64 Kbps conventional PCM for encoding and takes advantage of active talkpurts and silence intervals to increase the utilization efficiency of a digital link. The short-time energy and average zero-crossing rates calculated for the purpose of determining talkpurts are...
Show moreA waveform substitution technique using interpolation based on such slow varying parameters of speech as short-time energy and average zero-crossing rate is developed for a packetized speech communication system. The system uses 64 Kbps conventional PCM for encoding and takes advantage of active talkpurts and silence intervals to increase the utilization efficiency of a digital link. The short-time energy and average zero-crossing rates calculated for the purpose of determining talkpurts are transmitted in a preceeding packet. Hence, when a packet is pronounced "lost", its envelope and frequency characteristics are obtained from the previous packet and used to synthetize a substitution waveform which is free of annoying sounds that are due to abrupt changes in amplitude. Informal listening tests show that tolerable packet loss rate up to 40% are achievable with these procedures.
Show less - Date Issued
- 1991
- PURL
- http://purl.flvc.org/fcla/dt/14704
- Subject Headings
- Packet switching (Data transmission), Speech processing systems
- Format
- Document (PDF)
- Title
- Design of a signaling gateway to interoperate H.323 and SIP protocols.
- Creator
- Akbarian, Hamid., Florida Atlantic University, Hsu, Sam
- Abstract/Description
-
This thesis proposes a design for a signaling gateway to address the issues of interoperability between H.323 and SIP. The two IP Telephony standards currently compete for the dominance of IP telephony protocols. We investigate and study these two protocols in terms of interoperability. The question central to this thesis is the issue of interoperability between H.323 and SIP. A signaling gateway model is proposed and designed to address and solve this issue. The proposed model includes Call...
Show moreThis thesis proposes a design for a signaling gateway to address the issues of interoperability between H.323 and SIP. The two IP Telephony standards currently compete for the dominance of IP telephony protocols. We investigate and study these two protocols in terms of interoperability. The question central to this thesis is the issue of interoperability between H.323 and SIP. A signaling gateway model is proposed and designed to address and solve this issue. The proposed model includes Call Initialization, Call Setup and Control, Capability Exchange and Call Termination, which are the four fundamental features supported by H.323 and SIP for establishing calls. Furthermore, we design the four internal components, which are common to the four main functions mentioned above. These four components are type checking, decomposition, conversion and reformatting. In addition, we illustrate in six different cases the functionality of the proposed signaling gateway for establishing calls between H.323 and SIP. These six cases also demonstrate the conversion capability of the proposed signaling gateway during a call between H.323 and SIP endpoints.
Show less - Date Issued
- 2001
- PURL
- http://purl.flvc.org/fcla/dt/12784
- Subject Headings
- Internet telephony, Computer network protocols, Packet switching (Data transmission)
- Format
- Document (PDF)
- Title
- Performance evaluation of a DS/CDMA packet transmission system under Rician fading channel conditions.
- Creator
- Argyrides, Christodoulos., Florida Atlantic University, Aalo, Valentine A.
- Abstract/Description
-
This thesis is concerned with the performance analysis of a DS/CDMA packet radio system under Rician fading channel conditions. Analytic expressions are derived for the probability density functions and cumulative distribution functions of the total signal-to-interference ratio when considering mixed-type of interference sources. The users are divided into two groups: those that apply closed-loop power control and those that apply open-loop power control. Four different scenarios of power...
Show moreThis thesis is concerned with the performance analysis of a DS/CDMA packet radio system under Rician fading channel conditions. Analytic expressions are derived for the probability density functions and cumulative distribution functions of the total signal-to-interference ratio when considering mixed-type of interference sources. The users are divided into two groups: those that apply closed-loop power control and those that apply open-loop power control. Four different scenarios of power control were studied. The outage probability is evaluated for the four different cases of power control. A packet transmission protocol with forward error correction capabilities is considered, and the probability density functions of the signal-to-interference ratio are used to calculate the average block error probability as well as the outage probability of the system.
Show less - Date Issued
- 2001
- PURL
- http://purl.flvc.org/fcla/dt/12825
- Subject Headings
- Code division multiple access, Packet switching (Data transmission)
- Format
- Document (PDF)
- Title
- Path selection through a three-stage switching network using neural networks.
- Creator
- Keskiner, Haluk., Florida Atlantic University, Pandya, Abhijit S., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
Several neural network applications solving practical problems in communications are presented. A neural network algorithm to select paths through a three stage switching network is developed. An analysis of the dynamics of the neural network and a convergence proof are provided. With the help of computer simulations, a four dimensional region for the valid combinations of the neural network parameters was discovered. An analysis is performed to determine the characteristics of this region....
Show moreSeveral neural network applications solving practical problems in communications are presented. A neural network algorithm to select paths through a three stage switching network is developed. An analysis of the dynamics of the neural network and a convergence proof are provided. With the help of computer simulations, a four dimensional region for the valid combinations of the neural network parameters was discovered. An analysis is performed to determine the characteristics of this region. The behavior of the neural network algorithm for different switching network configurations and varying traffic patterns were investigated. The effect of initial state of the neural network and heuristic improvements to the algorithm is provided. A comparative analysis of the neural network path selection algorithm against a sequential search method is also given.
Show less - Date Issued
- 1991
- PURL
- http://purl.flvc.org/fcla/dt/14741
- Subject Headings
- Neural networks (Computer science), Packet switching (Data transmission)
- Format
- Document (PDF)
- Title
- A high-speed switching node architecture for ATM networks.
- Creator
- Syed, Majid Ali, Florida Atlantic University, Ilyas, Mohammad, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
This research is aimed towards the concept of a new switching node architecture for cell-switched Asynchronous Transfer Mode (ATM) networks. The proposed architecture has several distinguishing features when compared with existing Banyan based switching node. It has a cylindrical structure as opposed to a flat structure as found in Banyans. The wrap around property results in better link utilization as compared with existing Banyans beside resulting in reduced average route length. Simplified...
Show moreThis research is aimed towards the concept of a new switching node architecture for cell-switched Asynchronous Transfer Mode (ATM) networks. The proposed architecture has several distinguishing features when compared with existing Banyan based switching node. It has a cylindrical structure as opposed to a flat structure as found in Banyans. The wrap around property results in better link utilization as compared with existing Banyans beside resulting in reduced average route length. Simplified digit controlled routing is maintained as found in Banyans. The cylindrical nature of the architecture, results in pipeline activity. Such architecture tends to sort the traffic to a higher address, eliminating the need of a preprocessing node as a front end processing node. Approximate Markov chain analyses for the performance of the switching node with single input buffers is presented. The analyses are used to compute the time delay distribution of a cell leaving the node. A simulation tool is used to validate the analytical model. The simulation model is free from the critical assumptions which are necessary to develop the analytical model. It is shown that the analytical results closely match with the simulation results. This confirms the authenticity of the simulation model. We then study the performance of the switching node for various input buffer sizes. Low throughput with single input buffered switching node is observed; however, as the buffer size is increased from two to three the increase in throughput is more than 100%. No appreciable increase in node delay is noted when the buffer size is increased from two to three. We conclude that the optimum buffer size for large throughput is three and the maximum throughput with offered load of 0.9 and buffer size three is 0.75. This is because of head of line blocking phenomenon. A technique to overcome such inherent problem is presented. Several delays which a cell faces are analyzed and summarized below. The wait delay with buffer sizes one and two is high. However, the wait delay is negligible when the buffer size is increased beyond two. This is because increasing the buffer size reduces the head of line blocking. Thus more cells can move forward. Node delay and switched delay are comparable when the buffer size is greater than two. The delay offered is within a threshold range as noted for real time traffic. The delay is clock rate dependent and can be minimized by running the switching node at a higher clock speed. The worst delay noted for a switched cell for a node operating at a clock rate of 200 Mhz is 0.5 usec.
Show less - Date Issued
- 1992
- PURL
- http://purl.flvc.org/fcla/dt/12309
- Subject Headings
- Computer networks, Computer architecture, Packet switching (Data transmission)
- Format
- Document (PDF)
- Title
- A study on ATM multiplexing and threshold-based connection admission control in connection-oriented packet networks.
- Creator
- Yuan, Xiaohong., Florida Atlantic University, Ilyas, Mohammad, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
The research reported in this dissertation studies ATM multiplexing and connection admission control schemes for traffic management in connection-oriented packet networks. A new threshold-based connection admission control scheme is proposed and analyzed. The scheme uses effective bandwidth to make decision whether to accept or reject the connection request. This threshold specified effective-bandwidth method is first simulated on a simple 4-node connection-oriented packet network model, and...
Show moreThe research reported in this dissertation studies ATM multiplexing and connection admission control schemes for traffic management in connection-oriented packet networks. A new threshold-based connection admission control scheme is proposed and analyzed. The scheme uses effective bandwidth to make decision whether to accept or reject the connection request. This threshold specified effective-bandwidth method is first simulated on a simple 4-node connection-oriented packet network model, and then extended to a more complex 8-node network model under a variety of environments. To reduce the cell-loss ratio when the arrival rates of the connection requests are large, the dynamic effective bandwidth mechanism is proposed and relevant simulations are addressed on the two network models. The traffic used in the simulation is a multiplexed stream of cells from video, voice and data sources, which is typical in ATM environments. The multiplexed traffic is generated using a discrete event scheduling method. The simulation programs for the 4-node network model and for the 8-node network model are verified by the theoretical values of the blocking probabilities of the connection requests, and Little's Theorem. Simulations on the two network models show similar results. Pertinent to a network that supplying several service categories, the threshold-based connection admission control is shown to affect the blocking probabilities of each type of traffic. In some environments, having a threshold is advantageous over the case without a threshold in terms of cell-loss ratio, cell transfer delay and power (throughput divided by cell transfer delay). The simulation results also show that the dynamic effective bandwidth based method helps to reduce the cell-loss ratio significantly when the arrival rates of the connection requests are large.
Show less - Date Issued
- 2000
- PURL
- http://purl.flvc.org/fcla/dt/12647
- Subject Headings
- Asynchronous transfer mode, Packet switching (Data transmission), Telecommunication--Traffic
- Format
- Document (PDF)
- Title
- Neural network based routing optimization for ATM switching networks.
- Creator
- Sen, Ercan., Florida Atlantic University, Pandya, Abhijit S., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
This dissertation proposes amodular Artificial Neural Network (ANN) based buffer allocation and routing control model for ATM switching networks. The proposed model considers limited buffer capacity which can adversely impact the switching performance of ATM switching networks. The proposed ANN based approach takes advantage of the favorable control characteristics of neural networks such as high adaptability and high speed collective computing power for effective buffer utilization. The...
Show moreThis dissertation proposes amodular Artificial Neural Network (ANN) based buffer allocation and routing control model for ATM switching networks. The proposed model considers limited buffer capacity which can adversely impact the switching performance of ATM switching networks. The proposed ANN based approach takes advantage of the favorable control characteristics of neural networks such as high adaptability and high speed collective computing power for effective buffer utilization. The proposed model uses complete sharing buffer allocation strategy and enhances its performance for high traffic loads by regulating the buffer allocation process dynamically via a neural network based controller. In this study, we considered the buffer allocation problem in the context of routing optimization in ATM networks. The modular structure of the proposed model separates the buffer allocation from the actual routing of ATM cells through the switching fabric and allows adaptation of the neural control for routing to different switching structures. The influence of limited buffer capacity, routing conflicts, statistical correlation between arriving ATM cells and cell burst length on ATM switching performance are analyzed and illustrated through computer simulation.
Show less - Date Issued
- 1996
- PURL
- http://purl.flvc.org/fcla/dt/12491
- Subject Headings
- Asynchronous transfer mode, Packet switching (Data transmission), Neural networks (Computer science)
- Format
- Document (PDF)
- Title
- Performance analysis of multi-base station slotted ALOHA for wireless LAN in a Nakagami fading environment.
- Creator
- Chopra, Anju S., Florida Atlantic University, Aalo, Valentine A.
- Abstract/Description
-
Capture effect has shown considerable improvement on performance of slotted ALOHA systems. Further, improvement is expected by increasing the number of base stations. The performance of such slotted ALOHA systems is analyzed with the aid of Equilibrium point analysis. Packet dropping due to finite number of retransmissions is taken into account. The numerical results indicate that the finite number of retransmission trials mainly contribute to the improvement of the packet dropping...
Show moreCapture effect has shown considerable improvement on performance of slotted ALOHA systems. Further, improvement is expected by increasing the number of base stations. The performance of such slotted ALOHA systems is analyzed with the aid of Equilibrium point analysis. Packet dropping due to finite number of retransmissions is taken into account. The numerical results indicate that the finite number of retransmission trials mainly contribute to the improvement of the packet dropping probability in the range of light input traffic. The use of multiple base stations improves the overall throughput and the average transmission delay in the range of heavy input traffic.
Show less - Date Issued
- 1996
- PURL
- http://purl.flvc.org/fcla/dt/15268
- Subject Headings
- Local area networks (Computer networks), Wireless communication systems, Packet switching (Data transmission), Computer network protocols
- Format
- Document (PDF)
- Title
- Performance analysis of a very fast packet switching system for broadband ISDN.
- Creator
- Rao, Radha Nallur Seshagiri., Florida Atlantic University, Ilyas, Mohammad, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
Rapid advances in technology have resulted in the evolution of Integrated Services Digital Networks (ISDNs) to Broadband ISDNs (BISDNs). This thesis discusses and evaluates the performance of a high speed and high capacity packet switching system architecture for BISDNs. This system supports various high speed communication services like data, voice, and video services. The main performance criterion is the mean switching delay, which is defined as the packet transfer delay through the bus...
Show moreRapid advances in technology have resulted in the evolution of Integrated Services Digital Networks (ISDNs) to Broadband ISDNs (BISDNs). This thesis discusses and evaluates the performance of a high speed and high capacity packet switching system architecture for BISDNs. This system supports various high speed communication services like data, voice, and video services. The main performance criterion is the mean switching delay, which is defined as the packet transfer delay through the bus and through the loop connecting various switch modules in the system. Other performance criteria are power and system throughput. The performance parameters are evaluated separately for both data and control (signaling) packets. The effects of the number of switch modules in the system, the data packet length, and the ratio of arrival rate of data to control packets are examined. It is observed that the switching delay and throughput increase with an increase in the traffic intensity for any number of switching modules and the ratio of arrival rate of data to control packets. The delay for data packets is found to be higher for lower values of this ratio and vice versa. The power is found to be maximum for about 70% load. The switching delay in this simulation model is found to be less than one millisecond for data packets.
Show less - Date Issued
- 1990
- PURL
- http://purl.flvc.org/fcla/dt/14603
- Subject Headings
- Packet switching (Data transmission), Integrated services digital networks, Broadband communication systems
- Format
- Document (PDF)
- Title
- YACAD: Yet Another Congestion Avoidance Design for ATM-based networks.
- Creator
- Hsu, Sam, Florida Atlantic University, Ilyas, Mohammad, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
This dissertation proposes YACAD (Yet Another Congestion Avoidance Design for ATM-based Networks), a congestion prevention model that includes admission control, traffic shaping, and link-by-link flow control for ATM-based networks. Network traffic in this model is composed of real-time traffic and data traffic. As real-time traffic is delay-sensitive and connection-oriented, its call acceptance is based upon the effective bandwidth at all nodes. Effective bandwidth is defined as a vector of...
Show moreThis dissertation proposes YACAD (Yet Another Congestion Avoidance Design for ATM-based Networks), a congestion prevention model that includes admission control, traffic shaping, and link-by-link flow control for ATM-based networks. Network traffic in this model is composed of real-time traffic and data traffic. As real-time traffic is delay-sensitive and connection-oriented, its call acceptance is based upon the effective bandwidth at all nodes. Effective bandwidth is defined as a vector of bandwidth and maximum node delay. As data traffic can be either connection-oriented or connectionless, it is subject to link-by-link flow control based on a criterion known as effective buffer which is defined as a scalar of buffer size. Data traffic is not delay-sensitive but is loss-sensitive. Traffic shaping is imposed on real-time traffic to ensure a smooth inflow of real-time cells. YACAD also allocates a large buffer (fat bucket) to data traffic to accommodate sudden long bursts of data cells. Absence of data cell loss is a major feature of YACAD. Two simulation studies on the performance of the model are conducted. Analyses of the simulation results show that the proposed congestion avoidance model can achieve congestion-free networking and bounded network delays for real-time traffic at high levels of channel utilization. The maximum buffer requirements for loss-free cell delivery for data traffic, and the cell loss probabilities for real-time traffic are also obtained. In addition, results of performance comparisons to other similar models have shown that YACAD outperforms several other leaky-bucket based congestion control methods in terms of cell loss probability for real-time traffic. The simulation source program has also been verified using existing queueing theories, and the Paired-t Confidence Interval method with satisfactory results at 99% confidence level.
Show less - Date Issued
- 1993
- PURL
- http://purl.flvc.org/fcla/dt/12336
- Subject Headings
- Integrated services digital networks, Broadband communications systems, Packet switching (Data transmission), Computer networks--Management
- Format
- Document (PDF)
- Title
- Estimation of Internet transit times using a fast-computing artificial neural network (FC-ANN).
- Creator
- Fasulo, Joseph V., Florida Atlantic University, Neelakanta, Perambur S.
- Abstract/Description
-
The objective of this research is to determine the macroscopic behavior of packet transit-times across the global Internet cloud using an artificial neural network (ANN). Specifically, the problem addressed here refers to using a "fast-convergent" ANN for the purpose indicated. The underlying principle of fast-convergence is that, the data presented in training and prediction modes of the ANN is in the entropy (information-theoretic) domain, and the associated annealing process is "tuned" to...
Show moreThe objective of this research is to determine the macroscopic behavior of packet transit-times across the global Internet cloud using an artificial neural network (ANN). Specifically, the problem addressed here refers to using a "fast-convergent" ANN for the purpose indicated. The underlying principle of fast-convergence is that, the data presented in training and prediction modes of the ANN is in the entropy (information-theoretic) domain, and the associated annealing process is "tuned" to adopt only the useful information content and discard the posentropy part of the data presented. To demonstrate the efficacy of the research pursued, a feedforward ANN structure is developed and the necessary transformations required to convert the input data from the parametric-domain to the entropy-domain (and a corresponding inverse transformation) are followed so as to retrieve the output in parametric-domain. The fast-convergent or fast-computing ANN (FC-ANN) developed is deployed to predict the packet-transit performance across the Internet. (Abstract shortened by UMI.)
Show less - Date Issued
- 2001
- PURL
- http://purl.flvc.org/fcla/dt/12835
- Subject Headings
- Neural networks (Computer science), Information theory, Packet switching (Data transmission), Internet
- Format
- Document (PDF)
- Title
- A unified end-to-end priority strategy for traffic control in an ATM-based broadband ISDN.
- Creator
- Bemmel, Vincent Egbert., Florida Atlantic University, Ilyas, Mohammad, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
In order to guarantee a committed Quality of Service (QoS) to the users of a Broadband Integrated Services Digital Network (B-ISDN), preventive congestion control becomes critical, and is implemented through Call Acceptance Control (CAC) and Usage Parameter Control (UPC) functions. Currently, Asynchronous Transfer Mode (ATM) cells are equipped with a 1-bit Cell Loss Priority (CLP) field, which can be used for service-oriented and/or UPC marking. This creates a conflict, since these two...
Show moreIn order to guarantee a committed Quality of Service (QoS) to the users of a Broadband Integrated Services Digital Network (B-ISDN), preventive congestion control becomes critical, and is implemented through Call Acceptance Control (CAC) and Usage Parameter Control (UPC) functions. Currently, Asynchronous Transfer Mode (ATM) cells are equipped with a 1-bit Cell Loss Priority (CLP) field, which can be used for service-oriented and/or UPC marking. This creates a conflict, since these two marking approaches may have contradicting objectives, and are designed to operate independently. Moreover, by admitting excessive cells as marked traffic, this group is allowed to grow uncontrollably, thereby jeopardizing the QoS committed to other marked cells. This dissertation presents a solution to these problems by proposing a new 4-class priority strategy that unifies the two marking approaches, and is based on a 2-bit CLP field. The impacts of the new priority scheme are triple-fold: (I) For the UPC, a new scheme, the Forgiving Leaky Bucket (FLB), not only carries priorities through subnetwork boundaries, but also has the power of unmarking, i.e. forgiving, previously marked cells, depending on the bandwidth availability in the entering subnetwork. Forgiving will correct access-point bias, a phenomenon observed in internetworked ATM subnetworks of different congestion conditions. (II) At ATM switching nodes, a new space priority scheme is based on a hybrid of the Nested Threshold, and Push-Out cell discarding methods. This scheme is designed for the 4-class priority strategy, and improves the quality of the low priority traffic. (III) In interfacing High Speed Local Area Networks and Metropolitan Area Networks, idle bandwidth due to STM multiplexing is utilized to carry marked excessive cells of connection-oriented variable bit rate traffic, in addition to the service-oriented marking performed at transmitting stations. The resulting stream is then carried through internetworking points, subject to FLB adjustments. As a result, the STM and ATM subnetworks will support a uniform end-to-end priority strategy, essential for a B-ISDN. The proposed impacts are analyzed and compared with conventional implementations, and future directions are indicated.
Show less - Date Issued
- 1993
- PURL
- http://purl.flvc.org/fcla/dt/12334
- Subject Headings
- Integrated services digital networks, Broadband communication systems, Computer networks--Management, Packet switching (Data transmission)
- Format
- Document (PDF)
- Title
- A quality of service analysis of CDMA-based AODV routing protocol for ad-hoc wireless networks.
- Creator
- Qureshi, Basit Iqbal., Florida Atlantic University, Ilyas, Mohammad, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
Ad-hoc wireless networks are the networks without an infrastructure. Infrastructure-less mobile networks have no fixed routers or base stations. All nodes in these networks are capable of movement and can be connected dynamically at any time. The issue of routing packets effectively between any nodes in an ad-hoc network is a challenging task. A path that was considered optimal at a given time point may not be working after a few moments. Moreover the bandwidth available between a link may...
Show moreAd-hoc wireless networks are the networks without an infrastructure. Infrastructure-less mobile networks have no fixed routers or base stations. All nodes in these networks are capable of movement and can be connected dynamically at any time. The issue of routing packets effectively between any nodes in an ad-hoc network is a challenging task. A path that was considered optimal at a given time point may not be working after a few moments. Moreover the bandwidth available between a link may not remain the same since every node in this kind of network is behaving as a router and may experience drastical increase in throughput and traffic load. For the purpose of quality of communication, bandwidth reservation within ad-hoc wireless network nodes may prove promising as a solution to this problem. This thesis presents an approach to reserve bandwidth available utilizing CDMA of bandwidth to the Ad-hoc Distance Vector Protocol for the ad-hoc wireless networks. Various quality of service issues are discussed and are tested for optimal performance for AODV routing protocol. A QoS performance comparison based on mobility, congestion and throughput is made between AODV and CDMA based AODV mobile routing protocols.
Show less - Date Issued
- 2002
- PURL
- http://purl.flvc.org/fcla/dt/12895
- Subject Headings
- Code division multiple access, Wireless communication systems, Packet switching (Data transmission)
- Format
- Document (PDF)
- Title
- Simulation analysis of cluster-based multiprocessor systems.
- Creator
- De Armas, Mario Ernesto., Florida Atlantic University, Mahgoub, Imad
- Abstract/Description
-
Multiprocessor systems have demonstrated great potential for meeting the ever increasing demand for higher performance. In this thesis, we develop simulation models with fewer and more realistic assumptions to evaluate the performance of the circuit-switched cluster-based multiprocessor system. We then introduce a packet-switched variation of the cluster-based architecture and develop simulation models to evaluate its performance. The analysis of the cluster-based systems is performed for...
Show moreMultiprocessor systems have demonstrated great potential for meeting the ever increasing demand for higher performance. In this thesis, we develop simulation models with fewer and more realistic assumptions to evaluate the performance of the circuit-switched cluster-based multiprocessor system. We then introduce a packet-switched variation of the cluster-based architecture and develop simulation models to evaluate its performance. The analysis of the cluster-based systems is performed for both uniform and non-uniform memory reference models. We conducted similar analysis for the crossbar and multiple-bus systems. Finally, the results of the cluster-based systems are compared to those obtained for the crossbar and the multiple-bus systems.
Show less - Date Issued
- 1993
- PURL
- http://purl.flvc.org/fcla/dt/14969
- Subject Headings
- Multiprocessors, Cluster analysis, Packet switching (Data transmission), Computer architecture, Computer simulation
- Format
- Document (PDF)
- Title
- Performance analyses of Slotted ALOHA protocol in a Weibull fading environment.
- Creator
- Rene, Jean N., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
In past and recent literature, random access protocols have been investigated with growing interest. In particular, the Slotted ALOHA protocol has been extensively used in satellite communications, and has also attracted considerable attention in many areas of wireless communication systems, especially in the cellular mobile environment. In this thesis, we investigate the performance of Slotted ALOHA, an effective random access protocol, in a Weibull fading environment. We study the...
Show moreIn past and recent literature, random access protocols have been investigated with growing interest. In particular, the Slotted ALOHA protocol has been extensively used in satellite communications, and has also attracted considerable attention in many areas of wireless communication systems, especially in the cellular mobile environment. In this thesis, we investigate the performance of Slotted ALOHA, an effective random access protocol, in a Weibull fading environment. We study the performance metrics based on the signal-to-interference-and-noise ratio (SINR) model, in a cellular network system, assuming two captures models. The capture effect, also called co-channel interference tolerance, is the ability to correctly receive a strong signal from one transmitter despite significant interference from other transmitters. We derive closed-formed expressions and numerical evaluations for both the capture probability and the system throughput. he analytical results will be validated with computer simulations. Finally, to mitigate the effects of Weibull fading channel we also consider the effect of dual selection diversity that will increase the capture probability and the system throughput.
Show less - Date Issued
- 2013
- PURL
- http://purl.flvc.org/fcla/dt/3362567
- Subject Headings
- Multiple access protocols (Computer network protocols), Wireless communication systems, Packet switching (Data transmission), Computer simulation, Radio frequency identification systems, Computer simulation
- Format
- Document (PDF)