The Experts below are selected from a list of 462 Experts worldwide ranked by ideXlab platform
Ramiro Liscano - One of the best experts on this subject based on the ideXlab platform.
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ANT/SEIT - Evaluating Hamming Distance as a Metric for the Detection of CRC-based Side-channel Communications in MANETs
Procedia Computer Science, 2016Co-Authors: B. Moore, Miguel Vargas Martin, Ramiro LiscanoAbstract:Abstract Side-channel communication is a form of traffic in which malicious parties communicate secretly over a wireless network. This is often established through the modification of Ethernet frame header fields, such as the frame check sequence (FCS). The FCS is responsible for determining whether or not a frame has been corrupted in transmission, and contains a value calculated through the use of a predetermined polynomial. A malicious party may send messages that appear as nothing more than naturally corrupted noise on a network to those who are not the intended recipient. We use a metric known as Hamming distance in an attempt to differentiate purposely corrupted frames from naturally corrupted ones. In theory, it should be possible to recognize purposely corrupted frames based on how high this Hamming distance value is, as it signifies how many bits are different between the expected and the received FCS values. It is hypothesized that a range of threshold values based off of this metric exist, which may allow for the detection of side-channel communication across all scenarios. We ran an experiment with human subjects in a foot platoon formation and analyzed the data using a support vector machine. Our results show promise on the use of Hamming distance for side-channel detection in MANETs.
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ANT/SEIT - Evaluating Hamming Distance as a CRC-based Side-channel Detection Measure in Wi-Fi Networks
Procedia Computer Science, 2016Co-Authors: Visal Chea, Miguel Vargas Martin, Ramiro LiscanoAbstract:Abstract Wireless technology has become a main player in communication through its desirable mobility characteristic. However, like many technologies, there are ways that it can be exploited. One of these ways is through side-channel communication, whereby secret messages are passed along by the purposeful corruption of frames. These side channels can be established by intentionally corrupting the frame check sequence (FCS) field by using a Cyclic Redundancy check (CRC) polynomial that is different from the standard CRC polynomial. Malicious nodes can exploit the fact that normal unsuspecting nodes will drop these frames since they appear as naturally corrupted frames. This paper presents a CRC Hamming distance metric as a feature for the detection of this type of side-channel communication. We previously proposed the use of Hamming distance as a metric to compare CRC values that are generated by different CRC polynomials. The hypothesis is that the mean Hamming distance between two CRC values generated by two different CRC polynomials would be significantly far apart than the mean Hamming distance of a CRC value of a frame that was naturally corrupted but was generated by the same CRC polynomial. Previously, to test that hypothesis, we used F-Scores on real data experiments under varying noisy conditions and side-channel throughput to show that there is a consistent and significant difference between the mean Hamming values of naturally corrupted frames to those that use the Koopman polynomial to calculate the CRC for side-channel communications. In the present work we evaluate the Hamming distance using Perceptron Learning and the Pocket Algorithm to classify packets as side-channel or otherwise.
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Detection of Side-Channel Communication in a MANET Environment
2015 International Conference on Computational Science and Computational Intelligence (CSCI), 2015Co-Authors: B. Moore, Ramiro Liscano, M. Vargas MartinAbstract:Side-Channel communication is a form of traffic in which malicious parties communicate secretly over a wireless network. This is often established through the modification of Ethernet frame header fields, such as the frame check sequence (FCS). The FCS is responsible for determining whether or not a frame has been corrupted in transmission, and contains a value calculated through the use of a predetermined polynomial. A malicious party may send messages that appear as nothing more than naturally corrupted noise on a network to those who are not the intended recipient. A metric known as Hamming Distance (HD) has been proposed in an attempt to differentiate purposely corrupted frames from naturally corrupted ones. In theory, it should be possible to recognize purposely corrupted frames based on how high this HD value is, as it signifies how many bits are different between the expected and the received FCS values. It is hypothesized that a range of threshold values based off of this metric exist, which may allow for the detection of Side-Channel communication across all scenarios.
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CNS - Hamming distance as a metric for the detection of CRC-based side-channel communications in 802.11 wireless networks
2015 IEEE Conference on Communications and Network Security (CNS), 2015Co-Authors: Visal Chea, Miguel Vargas Martin, Ramiro LiscanoAbstract:Wireless technology has become a main player in communication through its desirable mobility characteristic. However, like many technologies, there are ways that it can be exploited. One of these ways is through side-channel communication, whereby secret messages are passed along by the purposeful corruption of frames. These side channels can be established by intentionally corrupting the frame check sequence (FCS) field by using a Cyclic Redundancy check (CRC) polynomial that is different from the standard CRC polynomial. Malicious nodes can exploit the fact that normal unsuspecting nodes will drop these frames since they appear as naturally corrupted frames. This paper presents a CRC Hamming distance metric as a feature for the detection of this type of side-channel communication. The proposed detection method applies the Hamming distance measure to compare CRC values that are generated by different CRC polynomials. The hypothesis is that the mean Hamming distance between two CRC values generated by two different CRC polynomials would be significantly far apart than the mean Hamming distance of a CRC value of a frame that was naturally corrupted but was generated by the same CRC polynomial. The results of our real data experiments show that the there is a consistent and significant difference between the mean Hamming values of naturally corrupted frames to those that use the Koopman polynomial to calculate the CRC for side-channel communications. The analysis of the results also demonstrate that the difference of the CRC values that have the the maximum F-Score vary between 10–14 under varying noisy conditions and side-channel throughput.
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ANT/MobiWIS - Challenges in the Implementation and Simulation for Wireless Side-Channel based on Intentionally Corrupted FCS
Procedia Computer Science, 2011Co-Authors: Ali Najafizadeh, Ramiro Liscano, Miguel Vargas Martin, Peter C. Mason, Mazda SalmanianAbstract:Abstract We report on the challenges faced in the implementation and simulation of a side-channel communication based on frames with an intentionally corrupted frame check sequence (FCS). Systematically corrupted FCSs can be used to enable covert communications between nodes that share the same algorithm for deciphering the FCS. In order to assess the possibility in detecting this side-channel communication it is necessary to have the ability to simulate it as well as to implement it on actual devices. Nearly all simulators drop corrupted frames before they reach their destination, making it impossible to simulate any side-channel communication based on intentionally corrupted FCS. We present an example of the modifications required to prevent this as applied to a well-known simulator called Sinalgo. We also discuss problems encountered when trying to intentionally corrupt the FCS on actual devices.
Yaw-chung Chen - One of the best experts on this subject based on the ideXlab platform.
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PSFCS: Robust Emergency Communications Supporting High Mobility Based on WiMAX MMR Networks
International Journal of Distributed Sensor Networks, 2014Co-Authors: Wen-kang Jia, Chia-yao Chen, Yaw-chung ChenAbstract:Nowadays public safety networks are widely deployed to support highly reliable wireless communications in case of emergency. The adoption of standardized systems such as WiMAX for emergency communications represents a significant advance in the off-the-shelf technologies for error detection and error correction. Since it is difficult to fully eliminate the Doppler effect under high speed moving environment, we propose an enhanced CRC-based error correction scheme that carries as much extra segmented frame check sequence (FCS) information as subblocks of emergency multicast/broadcast service (MBS) frame, called progressive and selective frame check sequence (PSFCS). In a mobile multihop relay (MMR) environment, a high-mobility mobile station might receive an emergency MBS frame more than once, so the PSFCS could be cross-referenced by duplicated frames received. Therefore the PSFCS achieves a significant performance improvement over the legacy FCS scheme in terms of error detection and correction of emergency MBS frames in a WiMAX MMR network operating in transparent mode. The experimental results show that the goodput and utilization of high-mobility mobile stations can be improved remarkably.
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GreenCom/iThings/CPScom - PSFCS: Robust Emergency Communications Supporting High-Mobility Based on WiMAX MMR Networks
2013 IEEE International Conference on Green Computing and Communications and IEEE Internet of Things and IEEE Cyber Physical and Social Computing, 2013Co-Authors: Wen-kang Jia, Chia-yao Chen, Yaw-chung ChenAbstract:Nowadays public safety networks are widely deployed to support highly reliable wireless communications in case of emergency. The adoption of standardized systems such as WiMAX for emergency communications represents a significant advance in the off-the-shelf technologies for error detection and error correction. Since it is difficult to fully eliminate the Doppler Effect under high-speed moving environment, we propose an enhanced CRC-based error correction scheme that carries as many extra segmented frame check sequence (FCS) information as sub-blocks of emergency MBS frame, called Progressive and Selective frame check sequence (PSFCS). In a Multi-hop Relay (MMR) environment, a high-mobility mobile station might receive an emergency MBS frame more than once, so the PSFCS could be cross referenced by duplicated frames received. Therefore the PSFCS achieves a significant performance improvement over the legacy FCS scheme in terms of error detection and correction of emergency MBS frames in a WiMAX MMR network operating in transparent mode. The experimental results show that the good put and utilization of high-mobility mobile stations can be improved remarkably.
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A cross-layer error correction scheme based on multiple-CRC in OFDM/OFDMA wireless networks
Journal of the Chinese Institute of Engineers, 2013Co-Authors: Chia-yao Chen, Wen-kang Jia, Yaw-chung ChenAbstract:The orthogonal frequency division multiplexing access (OFDM/OFDMA) based wireless transmission technology has been widely deployed in recent years. The frame check sequence (FCS) scheme is employed to enhance the reliability of OFDM/OFDMA systems. Since the padding overhead cannot be effectively avoided in OFDM/OFDMA when medium access control frames are encapsulated, we propose a novel cyclic redundancy check based error correction scheme by utilizing the padding space to carry extra segmented FCS information as much as possible; compared with the legacy FCS scheme, our approach greatly enhance the error detection and correction upon the first retransmission (second transmission). A significant performance improvement based on the simulation results is also demonstrated.
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Energy-efficient and reliable multicasting for WiMAX multi-hop relay networks
IET Communications, 2012Co-Authors: Chia-yao Chen, Wen-kang Jia, Yaw-chung ChenAbstract:Orthogonal frequency division multiplexing (OFDM)-based wireless transmission technologies such as WiMAX are now widely deployed, and the frame check sequence (FCS) scheme is used to enhance the reliability of OFDM-based systems. As the padding overhead cannot be completely avoided in such systems when variable-length medium access control (MAC) frames are encapsulated, the authors propose a novel cyclic redundancy check (CRC)-based error-correction scheme that utilises the frame padding overhead to carry as much extra segmented FCS information as possible. In a multi-hop relay environment, a mobile station might receive a multicast frame more than once, so the error bit correction scheme could be triggered in the first transmission. In the IEEE's work, the original CRC scheme is optional and only has limited error-detection capability in upper MAC layer. FCS requires a few bits in a frame, but in our work, CRC is compulsory and all sub-FCSs are carried by padding space without using any extra bit. For the best error-correction capability, all transmissions must be padded as many sub-FCSs are possible in cross layer. The proposed approach achieves a significant performance improvement over the legacy FCS scheme in terms of error detection and correction of multicast frames in a transparent mode multi-hop relay network, and it is redundancy-free as well as energy efficient. The authors assess the performance improvement via both mathematical analysis and simulations. The results show that the mobile stations get significant improvement of goodput and utilisation in an error-prone WiMAX multi-hop relay network.
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ISITA - A novel CRC based error correction scheme in OFDM/OFDMA wireless networks
2010 International Symposium On Information Theory & Its Applications, 2010Co-Authors: Chia-yao Chen, Wen-kang Jia, Yaw-chung ChenAbstract:Recently, the Orthogonal Frequency Division Multiplexing Access (OFDM/OFDMA) based wireless transmission technology has been widely accepted by consumers. frame check sequence (FCS) scheme was employed to enhance the reliability of OFDM/OFDMA systems. Since the padding overhead cannot be effectively avoided in OFDM/OFDMA when MAC frames are encapsulated. We propose a novel CRC based error correction scheme by utilizing the frame padding to carry extra segmented FCS information as much as possible; compared with legacy FCS scheme, our approach obtains a significant improvement in error detection and correction upon the first retransmission (2nd transmission). In addition, we demonstrate a significant performance improvement based on the mathematic analysis.
Miguel Vargas Martin - One of the best experts on this subject based on the ideXlab platform.
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ANT/SEIT - Evaluating Hamming Distance as a Metric for the Detection of CRC-based Side-channel Communications in MANETs
Procedia Computer Science, 2016Co-Authors: B. Moore, Miguel Vargas Martin, Ramiro LiscanoAbstract:Abstract Side-channel communication is a form of traffic in which malicious parties communicate secretly over a wireless network. This is often established through the modification of Ethernet frame header fields, such as the frame check sequence (FCS). The FCS is responsible for determining whether or not a frame has been corrupted in transmission, and contains a value calculated through the use of a predetermined polynomial. A malicious party may send messages that appear as nothing more than naturally corrupted noise on a network to those who are not the intended recipient. We use a metric known as Hamming distance in an attempt to differentiate purposely corrupted frames from naturally corrupted ones. In theory, it should be possible to recognize purposely corrupted frames based on how high this Hamming distance value is, as it signifies how many bits are different between the expected and the received FCS values. It is hypothesized that a range of threshold values based off of this metric exist, which may allow for the detection of side-channel communication across all scenarios. We ran an experiment with human subjects in a foot platoon formation and analyzed the data using a support vector machine. Our results show promise on the use of Hamming distance for side-channel detection in MANETs.
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ANT/SEIT - Evaluating Hamming Distance as a CRC-based Side-channel Detection Measure in Wi-Fi Networks
Procedia Computer Science, 2016Co-Authors: Visal Chea, Miguel Vargas Martin, Ramiro LiscanoAbstract:Abstract Wireless technology has become a main player in communication through its desirable mobility characteristic. However, like many technologies, there are ways that it can be exploited. One of these ways is through side-channel communication, whereby secret messages are passed along by the purposeful corruption of frames. These side channels can be established by intentionally corrupting the frame check sequence (FCS) field by using a Cyclic Redundancy check (CRC) polynomial that is different from the standard CRC polynomial. Malicious nodes can exploit the fact that normal unsuspecting nodes will drop these frames since they appear as naturally corrupted frames. This paper presents a CRC Hamming distance metric as a feature for the detection of this type of side-channel communication. We previously proposed the use of Hamming distance as a metric to compare CRC values that are generated by different CRC polynomials. The hypothesis is that the mean Hamming distance between two CRC values generated by two different CRC polynomials would be significantly far apart than the mean Hamming distance of a CRC value of a frame that was naturally corrupted but was generated by the same CRC polynomial. Previously, to test that hypothesis, we used F-Scores on real data experiments under varying noisy conditions and side-channel throughput to show that there is a consistent and significant difference between the mean Hamming values of naturally corrupted frames to those that use the Koopman polynomial to calculate the CRC for side-channel communications. In the present work we evaluate the Hamming distance using Perceptron Learning and the Pocket Algorithm to classify packets as side-channel or otherwise.
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CNS - Hamming distance as a metric for the detection of CRC-based side-channel communications in 802.11 wireless networks
2015 IEEE Conference on Communications and Network Security (CNS), 2015Co-Authors: Visal Chea, Miguel Vargas Martin, Ramiro LiscanoAbstract:Wireless technology has become a main player in communication through its desirable mobility characteristic. However, like many technologies, there are ways that it can be exploited. One of these ways is through side-channel communication, whereby secret messages are passed along by the purposeful corruption of frames. These side channels can be established by intentionally corrupting the frame check sequence (FCS) field by using a Cyclic Redundancy check (CRC) polynomial that is different from the standard CRC polynomial. Malicious nodes can exploit the fact that normal unsuspecting nodes will drop these frames since they appear as naturally corrupted frames. This paper presents a CRC Hamming distance metric as a feature for the detection of this type of side-channel communication. The proposed detection method applies the Hamming distance measure to compare CRC values that are generated by different CRC polynomials. The hypothesis is that the mean Hamming distance between two CRC values generated by two different CRC polynomials would be significantly far apart than the mean Hamming distance of a CRC value of a frame that was naturally corrupted but was generated by the same CRC polynomial. The results of our real data experiments show that the there is a consistent and significant difference between the mean Hamming values of naturally corrupted frames to those that use the Koopman polynomial to calculate the CRC for side-channel communications. The analysis of the results also demonstrate that the difference of the CRC values that have the the maximum F-Score vary between 10–14 under varying noisy conditions and side-channel throughput.
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ANT/MobiWIS - Challenges in the Implementation and Simulation for Wireless Side-Channel based on Intentionally Corrupted FCS
Procedia Computer Science, 2011Co-Authors: Ali Najafizadeh, Ramiro Liscano, Miguel Vargas Martin, Peter C. Mason, Mazda SalmanianAbstract:Abstract We report on the challenges faced in the implementation and simulation of a side-channel communication based on frames with an intentionally corrupted frame check sequence (FCS). Systematically corrupted FCSs can be used to enable covert communications between nodes that share the same algorithm for deciphering the FCS. In order to assess the possibility in detecting this side-channel communication it is necessary to have the ability to simulate it as well as to implement it on actual devices. Nearly all simulators drop corrupted frames before they reach their destination, making it impossible to simulate any side-channel communication based on intentionally corrupted FCS. We present an example of the modifications required to prevent this as applied to a well-known simulator called Sinalgo. We also discuss problems encountered when trying to intentionally corrupt the FCS on actual devices.
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LCN - A frame handler module for a side-channel in mobile ad hoc networks
2009 IEEE 34th Conference on Local Computer Networks, 2009Co-Authors: Marvin Odor, Miguel Vargas Martin, Peter C. Mason, Mazda Salmanian, Babak Nasri, Ramiro LiscanoAbstract:In this paper, we establish a hidden 802.11 wireless channel, with the masking of the channel achieved by inserting intentional errors in the frame check sequence (FCS). We design a frame handler module to provide a proof-of-concept model of the side-channel using MATLAB and Simulink with Communication Toolbox. We justify using MATLAB over the other simulation tools because of its existing functions: physical layer IEEE 802.11 wireless local area networking (WLAN) standard, existing modular channel fading models, the MAC layer cyclic redundancy checksum (CRC) generator, the CRC Syndrome detector, and the capability of modifying fields in a frame. These existing functions allow for the creation of a frame handler which generates frames, according to our design, to be inserted as erroneous frames and recovers frames from normal 802.11 traffic. Herein we provide the design and details of the implementation of the channel. Our design offers the ability to introduce error detection and correction capabilities, and protection against passive monitoring defences. This simulation framework is a step towards the development of more sophisticated environments including multi-node simulations that maintain robust and reliable side-channel communication.
Chia-yao Chen - One of the best experts on this subject based on the ideXlab platform.
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PSFCS: Robust Emergency Communications Supporting High Mobility Based on WiMAX MMR Networks
International Journal of Distributed Sensor Networks, 2014Co-Authors: Wen-kang Jia, Chia-yao Chen, Yaw-chung ChenAbstract:Nowadays public safety networks are widely deployed to support highly reliable wireless communications in case of emergency. The adoption of standardized systems such as WiMAX for emergency communications represents a significant advance in the off-the-shelf technologies for error detection and error correction. Since it is difficult to fully eliminate the Doppler effect under high speed moving environment, we propose an enhanced CRC-based error correction scheme that carries as much extra segmented frame check sequence (FCS) information as subblocks of emergency multicast/broadcast service (MBS) frame, called progressive and selective frame check sequence (PSFCS). In a mobile multihop relay (MMR) environment, a high-mobility mobile station might receive an emergency MBS frame more than once, so the PSFCS could be cross-referenced by duplicated frames received. Therefore the PSFCS achieves a significant performance improvement over the legacy FCS scheme in terms of error detection and correction of emergency MBS frames in a WiMAX MMR network operating in transparent mode. The experimental results show that the goodput and utilization of high-mobility mobile stations can be improved remarkably.
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GreenCom/iThings/CPScom - PSFCS: Robust Emergency Communications Supporting High-Mobility Based on WiMAX MMR Networks
2013 IEEE International Conference on Green Computing and Communications and IEEE Internet of Things and IEEE Cyber Physical and Social Computing, 2013Co-Authors: Wen-kang Jia, Chia-yao Chen, Yaw-chung ChenAbstract:Nowadays public safety networks are widely deployed to support highly reliable wireless communications in case of emergency. The adoption of standardized systems such as WiMAX for emergency communications represents a significant advance in the off-the-shelf technologies for error detection and error correction. Since it is difficult to fully eliminate the Doppler Effect under high-speed moving environment, we propose an enhanced CRC-based error correction scheme that carries as many extra segmented frame check sequence (FCS) information as sub-blocks of emergency MBS frame, called Progressive and Selective frame check sequence (PSFCS). In a Multi-hop Relay (MMR) environment, a high-mobility mobile station might receive an emergency MBS frame more than once, so the PSFCS could be cross referenced by duplicated frames received. Therefore the PSFCS achieves a significant performance improvement over the legacy FCS scheme in terms of error detection and correction of emergency MBS frames in a WiMAX MMR network operating in transparent mode. The experimental results show that the good put and utilization of high-mobility mobile stations can be improved remarkably.
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A cross-layer error correction scheme based on multiple-CRC in OFDM/OFDMA wireless networks
Journal of the Chinese Institute of Engineers, 2013Co-Authors: Chia-yao Chen, Wen-kang Jia, Yaw-chung ChenAbstract:The orthogonal frequency division multiplexing access (OFDM/OFDMA) based wireless transmission technology has been widely deployed in recent years. The frame check sequence (FCS) scheme is employed to enhance the reliability of OFDM/OFDMA systems. Since the padding overhead cannot be effectively avoided in OFDM/OFDMA when medium access control frames are encapsulated, we propose a novel cyclic redundancy check based error correction scheme by utilizing the padding space to carry extra segmented FCS information as much as possible; compared with the legacy FCS scheme, our approach greatly enhance the error detection and correction upon the first retransmission (second transmission). A significant performance improvement based on the simulation results is also demonstrated.
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Energy-efficient and reliable multicasting for WiMAX multi-hop relay networks
IET Communications, 2012Co-Authors: Chia-yao Chen, Wen-kang Jia, Yaw-chung ChenAbstract:Orthogonal frequency division multiplexing (OFDM)-based wireless transmission technologies such as WiMAX are now widely deployed, and the frame check sequence (FCS) scheme is used to enhance the reliability of OFDM-based systems. As the padding overhead cannot be completely avoided in such systems when variable-length medium access control (MAC) frames are encapsulated, the authors propose a novel cyclic redundancy check (CRC)-based error-correction scheme that utilises the frame padding overhead to carry as much extra segmented FCS information as possible. In a multi-hop relay environment, a mobile station might receive a multicast frame more than once, so the error bit correction scheme could be triggered in the first transmission. In the IEEE's work, the original CRC scheme is optional and only has limited error-detection capability in upper MAC layer. FCS requires a few bits in a frame, but in our work, CRC is compulsory and all sub-FCSs are carried by padding space without using any extra bit. For the best error-correction capability, all transmissions must be padded as many sub-FCSs are possible in cross layer. The proposed approach achieves a significant performance improvement over the legacy FCS scheme in terms of error detection and correction of multicast frames in a transparent mode multi-hop relay network, and it is redundancy-free as well as energy efficient. The authors assess the performance improvement via both mathematical analysis and simulations. The results show that the mobile stations get significant improvement of goodput and utilisation in an error-prone WiMAX multi-hop relay network.
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ISITA - A novel CRC based error correction scheme in OFDM/OFDMA wireless networks
2010 International Symposium On Information Theory & Its Applications, 2010Co-Authors: Chia-yao Chen, Wen-kang Jia, Yaw-chung ChenAbstract:Recently, the Orthogonal Frequency Division Multiplexing Access (OFDM/OFDMA) based wireless transmission technology has been widely accepted by consumers. frame check sequence (FCS) scheme was employed to enhance the reliability of OFDM/OFDMA systems. Since the padding overhead cannot be effectively avoided in OFDM/OFDMA when MAC frames are encapsulated. We propose a novel CRC based error correction scheme by utilizing the frame padding to carry extra segmented FCS information as much as possible; compared with legacy FCS scheme, our approach obtains a significant improvement in error detection and correction upon the first retransmission (2nd transmission). In addition, we demonstrate a significant performance improvement based on the mathematic analysis.
Wen-kang Jia - One of the best experts on this subject based on the ideXlab platform.
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PSFCS: Robust Emergency Communications Supporting High Mobility Based on WiMAX MMR Networks
International Journal of Distributed Sensor Networks, 2014Co-Authors: Wen-kang Jia, Chia-yao Chen, Yaw-chung ChenAbstract:Nowadays public safety networks are widely deployed to support highly reliable wireless communications in case of emergency. The adoption of standardized systems such as WiMAX for emergency communications represents a significant advance in the off-the-shelf technologies for error detection and error correction. Since it is difficult to fully eliminate the Doppler effect under high speed moving environment, we propose an enhanced CRC-based error correction scheme that carries as much extra segmented frame check sequence (FCS) information as subblocks of emergency multicast/broadcast service (MBS) frame, called progressive and selective frame check sequence (PSFCS). In a mobile multihop relay (MMR) environment, a high-mobility mobile station might receive an emergency MBS frame more than once, so the PSFCS could be cross-referenced by duplicated frames received. Therefore the PSFCS achieves a significant performance improvement over the legacy FCS scheme in terms of error detection and correction of emergency MBS frames in a WiMAX MMR network operating in transparent mode. The experimental results show that the goodput and utilization of high-mobility mobile stations can be improved remarkably.
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GreenCom/iThings/CPScom - PSFCS: Robust Emergency Communications Supporting High-Mobility Based on WiMAX MMR Networks
2013 IEEE International Conference on Green Computing and Communications and IEEE Internet of Things and IEEE Cyber Physical and Social Computing, 2013Co-Authors: Wen-kang Jia, Chia-yao Chen, Yaw-chung ChenAbstract:Nowadays public safety networks are widely deployed to support highly reliable wireless communications in case of emergency. The adoption of standardized systems such as WiMAX for emergency communications represents a significant advance in the off-the-shelf technologies for error detection and error correction. Since it is difficult to fully eliminate the Doppler Effect under high-speed moving environment, we propose an enhanced CRC-based error correction scheme that carries as many extra segmented frame check sequence (FCS) information as sub-blocks of emergency MBS frame, called Progressive and Selective frame check sequence (PSFCS). In a Multi-hop Relay (MMR) environment, a high-mobility mobile station might receive an emergency MBS frame more than once, so the PSFCS could be cross referenced by duplicated frames received. Therefore the PSFCS achieves a significant performance improvement over the legacy FCS scheme in terms of error detection and correction of emergency MBS frames in a WiMAX MMR network operating in transparent mode. The experimental results show that the good put and utilization of high-mobility mobile stations can be improved remarkably.
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A cross-layer error correction scheme based on multiple-CRC in OFDM/OFDMA wireless networks
Journal of the Chinese Institute of Engineers, 2013Co-Authors: Chia-yao Chen, Wen-kang Jia, Yaw-chung ChenAbstract:The orthogonal frequency division multiplexing access (OFDM/OFDMA) based wireless transmission technology has been widely deployed in recent years. The frame check sequence (FCS) scheme is employed to enhance the reliability of OFDM/OFDMA systems. Since the padding overhead cannot be effectively avoided in OFDM/OFDMA when medium access control frames are encapsulated, we propose a novel cyclic redundancy check based error correction scheme by utilizing the padding space to carry extra segmented FCS information as much as possible; compared with the legacy FCS scheme, our approach greatly enhance the error detection and correction upon the first retransmission (second transmission). A significant performance improvement based on the simulation results is also demonstrated.
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Energy-efficient and reliable multicasting for WiMAX multi-hop relay networks
IET Communications, 2012Co-Authors: Chia-yao Chen, Wen-kang Jia, Yaw-chung ChenAbstract:Orthogonal frequency division multiplexing (OFDM)-based wireless transmission technologies such as WiMAX are now widely deployed, and the frame check sequence (FCS) scheme is used to enhance the reliability of OFDM-based systems. As the padding overhead cannot be completely avoided in such systems when variable-length medium access control (MAC) frames are encapsulated, the authors propose a novel cyclic redundancy check (CRC)-based error-correction scheme that utilises the frame padding overhead to carry as much extra segmented FCS information as possible. In a multi-hop relay environment, a mobile station might receive a multicast frame more than once, so the error bit correction scheme could be triggered in the first transmission. In the IEEE's work, the original CRC scheme is optional and only has limited error-detection capability in upper MAC layer. FCS requires a few bits in a frame, but in our work, CRC is compulsory and all sub-FCSs are carried by padding space without using any extra bit. For the best error-correction capability, all transmissions must be padded as many sub-FCSs are possible in cross layer. The proposed approach achieves a significant performance improvement over the legacy FCS scheme in terms of error detection and correction of multicast frames in a transparent mode multi-hop relay network, and it is redundancy-free as well as energy efficient. The authors assess the performance improvement via both mathematical analysis and simulations. The results show that the mobile stations get significant improvement of goodput and utilisation in an error-prone WiMAX multi-hop relay network.
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ISITA - A novel CRC based error correction scheme in OFDM/OFDMA wireless networks
2010 International Symposium On Information Theory & Its Applications, 2010Co-Authors: Chia-yao Chen, Wen-kang Jia, Yaw-chung ChenAbstract:Recently, the Orthogonal Frequency Division Multiplexing Access (OFDM/OFDMA) based wireless transmission technology has been widely accepted by consumers. frame check sequence (FCS) scheme was employed to enhance the reliability of OFDM/OFDMA systems. Since the padding overhead cannot be effectively avoided in OFDM/OFDMA when MAC frames are encapsulated. We propose a novel CRC based error correction scheme by utilizing the frame padding to carry extra segmented FCS information as much as possible; compared with legacy FCS scheme, our approach obtains a significant improvement in error detection and correction upon the first retransmission (2nd transmission). In addition, we demonstrate a significant performance improvement based on the mathematic analysis.
