In this paper, a new Random Packet Access Protocol (RPAP) is proposed in WCDMA systems. The new proposed RPAP can efficiently prevent unnecessary interference by stopping a transmission if it is bound to be collided w...In this paper, a new Random Packet Access Protocol (RPAP) is proposed in WCDMA systems. The new proposed RPAP can efficiently prevent unnecessary interference by stopping a transmission if it is bound to be collided with others. Throughput about the new RPAP is deliberated and analyzed. Computer simulation shows that this protocol has better throughput performance compared with conventional one currently used in WCDMA.展开更多
Medium Access Control (MAC) protocol consists of sets of rules that determine which node is allowed to access the transmission medium. It provides mechanism for collision avoidance such that interfering sensor nodes d...Medium Access Control (MAC) protocol consists of sets of rules that determine which node is allowed to access the transmission medium. It provides mechanism for collision avoidance such that interfering sensor nodes do not transmit at the same time. In the literature, researchers have proposed different MAC protocols with features aimed at improving energy efficiency and thereby prolonging the life of sensor nodes. Sensor MAC, Time-out MAC (T-MAC), Dynamic Sensor MAC (DSMAC), WiseMAC, Quorum-based MAC (Queen-MAC) and Traffic Adaptive Medium Access Protocol (TRAMA) are some examples of proposed MAC protocols. There is a duration field in each transmitted packet. The value of this field indicates how long it will take to complete the remaining packet transmission. In the current paper, a novel energy-efficient MAC protocol is proposed based on the use of duration value in transmitted packets to setup varying sleep/wake-up schedules for neighbouring nodes of the receiver. The effectiveness of this proposed Packet-Duration-Value-based MAC (PDV-MAC) protocol is tested via Simulation which is implemented in Visual C# and MATLAB. It is shown by the results obtained that the proposed MAC protocol can indeed be implemented in sensor nodes to improve energy efficiency in wireless sensor network.展开更多
The performance of ALOHA, Non-Persistent CSMA protocols and their slotted versions in Packet Radio Network is analyzed in consideration of the time of propagation delay, the time of radio transformation from receiving...The performance of ALOHA, Non-Persistent CSMA protocols and their slotted versions in Packet Radio Network is analyzed in consideration of the time of propagation delay, the time of radio transformation from receiving state to transmitting state, and the time for the radio to sense the carrier. The analysis shows that these parameters are the main factors deteriorating the performance of the protocols, especially for CSMA. The multichannel mode efficiently decreases the effects of these factors and the system capacity is changeable conveniently. Comparing curves and some simulation results are given.展开更多
Considering that weak channel collision detection ability, long propagation delay and heavy load in LEO satellite communications, a valid adaptive APRMA MAC protocol was proposed. Different access probability function...Considering that weak channel collision detection ability, long propagation delay and heavy load in LEO satellite communications, a valid adaptive APRMA MAC protocol was proposed. Different access probability functions for different services were obtained and appropriate access probabilities for voice and data users were updated slot by slot based on the estimation of the voice traffic and the channel status. In the proposed MAC protocol limited wireless resource is allocated reasonably by multiple users and high capacity was achieved. Three performance parameters: voice packet loss probability, average delay of data packets and throughput of data packets were considered in simulation. Finally simulation results demonstrated that the performance of system was improved by the APRMA compared with the conventional PRMA, with an acceptable trade-off between QoS of voice and delay of data.展开更多
With the development of computer technology, network bandwidth and network traffic continue to increase. Considering the large data flow, it is imperative to perform inspection effectively on network packets. In order...With the development of computer technology, network bandwidth and network traffic continue to increase. Considering the large data flow, it is imperative to perform inspection effectively on network packets. In order to find a solution of deep packet inspection which can appropriate to the current network environment, this paper built a deep packet inspection system based on many-core platform, and in this way, verified the feasibility to implement a deep packet inspection system under many-core platform with both high performance and low consumption. After testing and analysis of the system performance, it has been found that the deep packet inspection based on many-core platform TILE_Gx36 [1] [2] can process network traffic of which the bandwidth reaches up to 4 Gbps. To a certain extent, the performance has improved compared to most deep packet inspection system based on X86 platform at present.展开更多
Based on a media access and control（MAC）protocol,an arrangement of channels and transceivers in optical packet switching dense wavelength division multiplexing（DWDM）networks is proposed in this paper.In order to r...Based on a media access and control（MAC）protocol,an arrangement of channels and transceivers in optical packet switching dense wavelength division multiplexing（DWDM）networks is proposed in this paper.In order to reduce the cost of nodes,fixed transmitters and receivers are used instead of tunable transmitters and receivers.Two fixed transmitters and many fixed receivers are used in each node in the scheme.The average waiting delay of this scheme is analyzed through mathematics and computer simulation.The result shows that the property of the scheme is almost the same as using tunable transmitter and receiver.Furthermore,if the tuning time of tunable transmitters is taken into account,the performance of the tunable transmitter scheme is poor than this scheme at the average waiting delay and throughput of the network.展开更多
This research paper describes the design and implementation of the Consultative Committee for Space Data Systems (CCSDS) standards REF _Ref401069962 \r \h \* MERGEFORMAT [1] for Space Data Link Layer Protocol (SDLP). ...This research paper describes the design and implementation of the Consultative Committee for Space Data Systems (CCSDS) standards REF _Ref401069962 \r \h \* MERGEFORMAT [1] for Space Data Link Layer Protocol (SDLP). The primer focus is the telecommand (TC) part of the standard. The implementation of the standard was in the form of DLL functions using C++ programming language. The second objective of this paper was to use the DLL functions with OMNeT++ simulating environment to create a simulator in order to analyze the mean end-to-end Packet Delay, maximum achievable application layer throughput for a given fixed link capacity and normalized protocol overhead, defined as the total number of bytes transmitted on the link in a given period of time (e.g. per second) divided by the number of bytes of application data received at the application layer model data sink. In addition, the DLL was also integrated with Ground Support Equipment Operating System (GSEOS), a software system for space instruments and small spacecrafts especially suited for low budget missions. The SDLP is designed for rapid test system design and high flexibility for changing telemetry and command requirements. GSEOS can be seamlessly moved from EM/FM development (bench testing) to flight operations. It features the Python programming language as a configuration/scripting tool and can easily be extended to accommodate custom hardware interfaces. This paper also shows the results of the simulations and its analysis.展开更多
The necessary background as well as the details of simulation was presented to simulate and evaluate the performance of the ad hoc on-demand distance vector routing protocol in mobile ad hoc network with the help of t...The necessary background as well as the details of simulation was presented to simulate and evaluate the performance of the ad hoc on-demand distance vector routing protocol in mobile ad hoc network with the help of the network simulator NS2 using the common transmission range to deliver the data packets at the destination node. The number of participating nodes played an important role to predict the conditions for the best performance of the protocol with respect to throughput, delay, packet delivery ratio, drop packets, consumed and residual energy of the network. Further, the efforts can be put to control the transmission range dynamically and overheads for reducing the energy consumption in the network and improving its lifetime of the nodes and the lifespan of the network.展开更多
In this article, a routing protocol EARP (Energy Aware Routing Protocol) with the terminal node is proposed, to deal with the impact of the limited energy resources of Cognitive Radio Networks on the whole network rou...In this article, a routing protocol EARP (Energy Aware Routing Protocol) with the terminal node is proposed, to deal with the impact of the limited energy resources of Cognitive Radio Networks on the whole network routing. The protocol allows choosing the route from the neighbor nodes in different transmission paths, according to energy consumption of a single node and the full path. If the path breaks, the protocol will increase local routing maintenance strategy. It effectively reduces the retransmission caused by the situation, and improves the routing efficiency. It also can prevent the link transmission process selecting the fault route due to the energy depletion. Through simulation experiments compared with the LEACH (Low Energy Adaptive Clustering Hierarchy) routing protocol, the results showed that in the same experimental environment, the proposed EARP could obviously balance the load, protect low energy nodes, prolong the network survival time and reduce packet loss rate and packet delay of data delivery. So it can improve the energy consumption of sensing node and provide routing capabilities.展开更多
文摘In this paper, a new Random Packet Access Protocol (RPAP) is proposed in WCDMA systems. The new proposed RPAP can efficiently prevent unnecessary interference by stopping a transmission if it is bound to be collided with others. Throughput about the new RPAP is deliberated and analyzed. Computer simulation shows that this protocol has better throughput performance compared with conventional one currently used in WCDMA.
文摘Medium Access Control (MAC) protocol consists of sets of rules that determine which node is allowed to access the transmission medium. It provides mechanism for collision avoidance such that interfering sensor nodes do not transmit at the same time. In the literature, researchers have proposed different MAC protocols with features aimed at improving energy efficiency and thereby prolonging the life of sensor nodes. Sensor MAC, Time-out MAC (T-MAC), Dynamic Sensor MAC (DSMAC), WiseMAC, Quorum-based MAC (Queen-MAC) and Traffic Adaptive Medium Access Protocol (TRAMA) are some examples of proposed MAC protocols. There is a duration field in each transmitted packet. The value of this field indicates how long it will take to complete the remaining packet transmission. In the current paper, a novel energy-efficient MAC protocol is proposed based on the use of duration value in transmitted packets to setup varying sleep/wake-up schedules for neighbouring nodes of the receiver. The effectiveness of this proposed Packet-Duration-Value-based MAC (PDV-MAC) protocol is tested via Simulation which is implemented in Visual C# and MATLAB. It is shown by the results obtained that the proposed MAC protocol can indeed be implemented in sensor nodes to improve energy efficiency in wireless sensor network.
文摘The performance of ALOHA, Non-Persistent CSMA protocols and their slotted versions in Packet Radio Network is analyzed in consideration of the time of propagation delay, the time of radio transformation from receiving state to transmitting state, and the time for the radio to sense the carrier. The analysis shows that these parameters are the main factors deteriorating the performance of the protocols, especially for CSMA. The multichannel mode efficiently decreases the effects of these factors and the system capacity is changeable conveniently. Comparing curves and some simulation results are given.
文摘Considering that weak channel collision detection ability, long propagation delay and heavy load in LEO satellite communications, a valid adaptive APRMA MAC protocol was proposed. Different access probability functions for different services were obtained and appropriate access probabilities for voice and data users were updated slot by slot based on the estimation of the voice traffic and the channel status. In the proposed MAC protocol limited wireless resource is allocated reasonably by multiple users and high capacity was achieved. Three performance parameters: voice packet loss probability, average delay of data packets and throughput of data packets were considered in simulation. Finally simulation results demonstrated that the performance of system was improved by the APRMA compared with the conventional PRMA, with an acceptable trade-off between QoS of voice and delay of data.
文摘With the development of computer technology, network bandwidth and network traffic continue to increase. Considering the large data flow, it is imperative to perform inspection effectively on network packets. In order to find a solution of deep packet inspection which can appropriate to the current network environment, this paper built a deep packet inspection system based on many-core platform, and in this way, verified the feasibility to implement a deep packet inspection system under many-core platform with both high performance and low consumption. After testing and analysis of the system performance, it has been found that the deep packet inspection based on many-core platform TILE_Gx36 [1] [2] can process network traffic of which the bandwidth reaches up to 4 Gbps. To a certain extent, the performance has improved compared to most deep packet inspection system based on X86 platform at present.
文摘Based on a media access and control（MAC）protocol,an arrangement of channels and transceivers in optical packet switching dense wavelength division multiplexing（DWDM）networks is proposed in this paper.In order to reduce the cost of nodes,fixed transmitters and receivers are used instead of tunable transmitters and receivers.Two fixed transmitters and many fixed receivers are used in each node in the scheme.The average waiting delay of this scheme is analyzed through mathematics and computer simulation.The result shows that the property of the scheme is almost the same as using tunable transmitter and receiver.Furthermore,if the tuning time of tunable transmitters is taken into account,the performance of the tunable transmitter scheme is poor than this scheme at the average waiting delay and throughput of the network.
文摘This research paper describes the design and implementation of the Consultative Committee for Space Data Systems (CCSDS) standards REF _Ref401069962 \r \h \* MERGEFORMAT [1] for Space Data Link Layer Protocol (SDLP). The primer focus is the telecommand (TC) part of the standard. The implementation of the standard was in the form of DLL functions using C++ programming language. The second objective of this paper was to use the DLL functions with OMNeT++ simulating environment to create a simulator in order to analyze the mean end-to-end Packet Delay, maximum achievable application layer throughput for a given fixed link capacity and normalized protocol overhead, defined as the total number of bytes transmitted on the link in a given period of time (e.g. per second) divided by the number of bytes of application data received at the application layer model data sink. In addition, the DLL was also integrated with Ground Support Equipment Operating System (GSEOS), a software system for space instruments and small spacecrafts especially suited for low budget missions. The SDLP is designed for rapid test system design and high flexibility for changing telemetry and command requirements. GSEOS can be seamlessly moved from EM/FM development (bench testing) to flight operations. It features the Python programming language as a configuration/scripting tool and can easily be extended to accommodate custom hardware interfaces. This paper also shows the results of the simulations and its analysis.
文摘The necessary background as well as the details of simulation was presented to simulate and evaluate the performance of the ad hoc on-demand distance vector routing protocol in mobile ad hoc network with the help of the network simulator NS2 using the common transmission range to deliver the data packets at the destination node. The number of participating nodes played an important role to predict the conditions for the best performance of the protocol with respect to throughput, delay, packet delivery ratio, drop packets, consumed and residual energy of the network. Further, the efforts can be put to control the transmission range dynamically and overheads for reducing the energy consumption in the network and improving its lifetime of the nodes and the lifespan of the network.
文摘In this article, a routing protocol EARP (Energy Aware Routing Protocol) with the terminal node is proposed, to deal with the impact of the limited energy resources of Cognitive Radio Networks on the whole network routing. The protocol allows choosing the route from the neighbor nodes in different transmission paths, according to energy consumption of a single node and the full path. If the path breaks, the protocol will increase local routing maintenance strategy. It effectively reduces the retransmission caused by the situation, and improves the routing efficiency. It also can prevent the link transmission process selecting the fault route due to the energy depletion. Through simulation experiments compared with the LEACH (Low Energy Adaptive Clustering Hierarchy) routing protocol, the results showed that in the same experimental environment, the proposed EARP could obviously balance the load, protect low energy nodes, prolong the network survival time and reduce packet loss rate and packet delay of data delivery. So it can improve the energy consumption of sensing node and provide routing capabilities.
