Tomography is important for network design and routing optimization. Prior approaches require either
precise time synchronization or complex cooperation. Furthermore, active tomography consumes explicit
probing resulting in limited scalability. To address the first issue we propose a novel Delay Correlation
Estimation methodology named DCE with no need of synchronization and special cooperation. For the
second issue we develop a passive realization mechanism merely using regular data flow without explicit
bandwidth consumption. Extensive simulations in OMNeT++ are made to evaluate its accuracy where we
show that DCE measurement is highly identical with the true value. Also from test result we find that
mechanism of passive realization is able to achieve both regular data transmission and purpose of
tomography with excellent robustness versus different background traffic and package size.
Tomography is important for network design and routing optimization. Prior approaches require either
precise time synchronization or complex cooperation. Furthermore, active tomography consumes explicit
probing resulting in limited scalability. To address the first issue we propose a novel Delay Correlation
Estimation methodology named DCE with no need of synchronization and special cooperation. For the
second issue we develop a passive realization mechanism merely using regular data flow without explicit
bandwidth consumption. Extensive simulations in OMNeT++ are made to evaluate its accuracy where we
show that DCE measurement is highly identical with the true value. Also from test result we find that
mechanism of passive realization is able to achieve both regular data transmission and purpose of
tomography with excellent robustness versus different background traffic and package size.
A comparison of efficient algorithms for scheduling parallel data redistributionIJCNCJournal
Data redistribution in parallel is an often-address
ed issue in modern computer networks. In this conte
xt, we
study the case of data redistribution over a switch
ing network. Data from the source stations need to
be
transferred to the destination stations in the mini
mum time possible. Unfortunately the time required
to
complete the transfer is burdened by each switching
and thus producing an optimal schedule is proven t
o
be computationally intractable. For the purposes of
this paper we consider two algorithms, which have
been proved to be very efficient in the past. To ge
t improved results in comparison to previous approa
ches,
we propose splitting the data in two clusters depen
ding on the size of the data to be transferred. To
prove
the efficiency of our approach we ran experiments o
n all three algorithms, comparing the time span of
the
schedules produced as well as the running times to
produce those schedules. The test cases we ran
indicate that not only our newly proposed algorithm
yields better results in terms of the schedule pro
duced
but runs faster as well.
A Review: Compensation of Mismatches in Time Interleaved Analog to Digital Co...IJERA Editor
The execution of today's correspondence frameworks is exceedingly subject to the utilized Analog-to-Digital converters (ADCs), and with a specific end goal to give more flexibility and exactness to the developing correspondence innovations, superior-ADCs are needed. In this respect, the time-interleaved operation of an exhibit of ADCs (TI-ADC) might be a sensible result. A TI-ADC can build its throughput by utilizing M channel ADCs or sub converters in parallel and examining the data motion in a period-interleaved way. In any case, the execution of a TI-ADC gravely suffers from the bungles around the channel ADCs. In this paper we survey the advancement in the configuration of low-intricacy advanced remedy structures and calculations for time-interleaved ADCs in the course of the most recent five years. We devise a discrete-time model, state the outline issue, and finally infer the calculations and structures. Specifically, we examine proficient calculations to outline time-differing remedy filters and additionally iterative structures using polynomial based filters. Thusly, the remuneration structure may be utilized to repay time-differing recurrence reaction befuddles in time-interleaved ADCs, and in addition to remake uniform examples from nonuniformly tested indicators. We examine the recompense structure, research its execution, and exhibit requisition zones of the structure through various illustrations. At long last, we give a standpoint to future examination questions.
ENHANCEMENT OF TRANSMISSION RANGE ASSIGNMENT FOR CLUSTERED WIRELESS SENSOR NE...IJCNCJournal
Transmitter range assignment in clustered wireless networks is the bottleneck of the balance between
energy conservation and the connectivity to deliver data to the sink or gateway node. The aim of this
research is to optimize the energy consumption through reducing the transmission ranges of the nodes,
while maintaining high probability to have end-to-end connectivity to the network’s data sink. We modified
the approach given in [1] to achieve more than 25% power saving through reducing cluster head (CH)
transmission range of the backbone nodes in a multihop wireless sensor network with ensuring at least
95% end-to-end connectivity probability.
IEEE PROJECTS 2015
1 crore projects is a leading Guide for ieee Projects and real time projects Works Provider.
It has been provided Lot of Guidance for Thousands of Students & made them more beneficial in all Technology Training.
Dot Net
DOTNET Project Domain list 2015
1. IEEE based on datamining and knowledge engineering
2. IEEE based on mobile computing
3. IEEE based on networking
4. IEEE based on Image processing
5. IEEE based on Multimedia
6. IEEE based on Network security
7. IEEE based on parallel and distributed systems
Java Project Domain list 2015
1. IEEE based on datamining and knowledge engineering
2. IEEE based on mobile computing
3. IEEE based on networking
4. IEEE based on Image processing
5. IEEE based on Multimedia
6. IEEE based on Network security
7. IEEE based on parallel and distributed systems
ECE IEEE Projects 2015
1. Matlab project
2. Ns2 project
3. Embedded project
4. Robotics project
Eligibility
Final Year students of
1. BSc (C.S)
2. BCA/B.E(C.S)
3. B.Tech IT
4. BE (C.S)
5. MSc (C.S)
6. MSc (IT)
7. MCA
8. MS (IT)
9. ME(ALL)
10. BE(ECE)(EEE)(E&I)
TECHNOLOGY USED AND FOR TRAINING IN
1. DOT NET
2. C sharp
3. ASP
4. VB
5. SQL SERVER
6. JAVA
7. J2EE
8. STRINGS
9. ORACLE
10. VB dotNET
11. EMBEDDED
12. MAT LAB
13. LAB VIEW
14. Multi Sim
CONTACT US
1 CRORE PROJECTS
Door No: 214/215,2nd Floor,
No. 172, Raahat Plaza, (Shopping Mall) ,Arcot Road, Vadapalani, Chennai,
Tamin Nadu, INDIA - 600 026
Email id: 1croreprojects@gmail.com
website:1croreprojects.com
Phone : +91 97518 00789 / +91 72999 51536
RADIAL BASIS FUNCTION PROCESS NEURAL NETWORK TRAINING BASED ON GENERALIZED FR...cseij
For learning problem of Radial Basis Function Process Neural Network (RBF-PNN), an optimization
training method based on GA combined with SA is proposed in this paper. Through building generalized
Fréchet distance to measure similarity between time-varying function samples, the learning problem of
radial basis centre functions and connection weights is converted into the training on corresponding
discrete sequence coefficients. Network training objective function is constructed according to the least
square error criterion, and global optimization solving of network parameters is implemented in feasible
solution space by use of global optimization feature of GA and probabilistic jumping property of SA . The
experiment results illustrate that the training algorithm improves the network training efficiency and
stability.
Improved Timing Estimation Using Iterative Normalization Technique for OFDM S...IJECEIAES
Conventional timing estimation schemes based on autocorrelation experience perfor- mance degradation in the multipath channel environment with high delay spread. To overcome this problem, we proposed an improvement of the timing estimation for the OFDM system based on statistical change of symmetrical correlator. The new method uses iterative normalization technique to the correlator output before the detection based on statistical change of symmetric correlator is applied. Thus, it increases the detection probability and achieves better performance than previously published methods in the multipath environment. Computer simulation shows that our method is very robust in the fading multipath channel.
Exact network reconstruction from consensus signals and one eigen valueIJCNCJournal
The basic inverse problem in spectral graph theory consists in determining the graph given its eigenvalue
spectrum. In this paper, we are interested in a network of technological agents whose graph is unknown,
communicating by means of a consensus protocol. Recently, the use of artificial noise added to consensus
signals has been proposed to reconstruct the unknown graph, although errors are possible. On the other
hand, some methodologies have been devised to estimate the eigenvalue spectrum, but noise could interfere
with the elaborations. We combine these two techniques in order to simplify calculations and avoid
topological reconstruction errors, using only one eigenvalue. Moreover, we use an high frequency noise to
reconstruct the network, thus it is easy to filter the control signals after the graph identification. Numerical
simulations of several topologies show an exact and robust reconstruction of the graphs.
Tomography is important for network design and routing optimization. Prior approaches require either
precise time synchronization or complex cooperation. Furthermore, active tomography consumes explicit
probing resulting in limited scalability. To address the first issue we propose a novel Delay Correlation
Estimation methodology named DCE with no need of synchronization and special cooperation. For the
second issue we develop a passive realization mechanism merely using regular data flow without explicit
bandwidth consumption. Extensive simulations in OMNeT++ are made to evaluate its accuracy where we
show that DCE measurement is highly identical with the true value. Also from test result we find that
mechanism of passive realization is able to achieve both regular data transmission and purpose of
tomography with excellent robustness versus different background traffic and package size.
A comparison of efficient algorithms for scheduling parallel data redistributionIJCNCJournal
Data redistribution in parallel is an often-address
ed issue in modern computer networks. In this conte
xt, we
study the case of data redistribution over a switch
ing network. Data from the source stations need to
be
transferred to the destination stations in the mini
mum time possible. Unfortunately the time required
to
complete the transfer is burdened by each switching
and thus producing an optimal schedule is proven t
o
be computationally intractable. For the purposes of
this paper we consider two algorithms, which have
been proved to be very efficient in the past. To ge
t improved results in comparison to previous approa
ches,
we propose splitting the data in two clusters depen
ding on the size of the data to be transferred. To
prove
the efficiency of our approach we ran experiments o
n all three algorithms, comparing the time span of
the
schedules produced as well as the running times to
produce those schedules. The test cases we ran
indicate that not only our newly proposed algorithm
yields better results in terms of the schedule pro
duced
but runs faster as well.
A Review: Compensation of Mismatches in Time Interleaved Analog to Digital Co...IJERA Editor
The execution of today's correspondence frameworks is exceedingly subject to the utilized Analog-to-Digital converters (ADCs), and with a specific end goal to give more flexibility and exactness to the developing correspondence innovations, superior-ADCs are needed. In this respect, the time-interleaved operation of an exhibit of ADCs (TI-ADC) might be a sensible result. A TI-ADC can build its throughput by utilizing M channel ADCs or sub converters in parallel and examining the data motion in a period-interleaved way. In any case, the execution of a TI-ADC gravely suffers from the bungles around the channel ADCs. In this paper we survey the advancement in the configuration of low-intricacy advanced remedy structures and calculations for time-interleaved ADCs in the course of the most recent five years. We devise a discrete-time model, state the outline issue, and finally infer the calculations and structures. Specifically, we examine proficient calculations to outline time-differing remedy filters and additionally iterative structures using polynomial based filters. Thusly, the remuneration structure may be utilized to repay time-differing recurrence reaction befuddles in time-interleaved ADCs, and in addition to remake uniform examples from nonuniformly tested indicators. We examine the recompense structure, research its execution, and exhibit requisition zones of the structure through various illustrations. At long last, we give a standpoint to future examination questions.
ENHANCEMENT OF TRANSMISSION RANGE ASSIGNMENT FOR CLUSTERED WIRELESS SENSOR NE...IJCNCJournal
Transmitter range assignment in clustered wireless networks is the bottleneck of the balance between
energy conservation and the connectivity to deliver data to the sink or gateway node. The aim of this
research is to optimize the energy consumption through reducing the transmission ranges of the nodes,
while maintaining high probability to have end-to-end connectivity to the network’s data sink. We modified
the approach given in [1] to achieve more than 25% power saving through reducing cluster head (CH)
transmission range of the backbone nodes in a multihop wireless sensor network with ensuring at least
95% end-to-end connectivity probability.
IEEE PROJECTS 2015
1 crore projects is a leading Guide for ieee Projects and real time projects Works Provider.
It has been provided Lot of Guidance for Thousands of Students & made them more beneficial in all Technology Training.
Dot Net
DOTNET Project Domain list 2015
1. IEEE based on datamining and knowledge engineering
2. IEEE based on mobile computing
3. IEEE based on networking
4. IEEE based on Image processing
5. IEEE based on Multimedia
6. IEEE based on Network security
7. IEEE based on parallel and distributed systems
Java Project Domain list 2015
1. IEEE based on datamining and knowledge engineering
2. IEEE based on mobile computing
3. IEEE based on networking
4. IEEE based on Image processing
5. IEEE based on Multimedia
6. IEEE based on Network security
7. IEEE based on parallel and distributed systems
ECE IEEE Projects 2015
1. Matlab project
2. Ns2 project
3. Embedded project
4. Robotics project
Eligibility
Final Year students of
1. BSc (C.S)
2. BCA/B.E(C.S)
3. B.Tech IT
4. BE (C.S)
5. MSc (C.S)
6. MSc (IT)
7. MCA
8. MS (IT)
9. ME(ALL)
10. BE(ECE)(EEE)(E&I)
TECHNOLOGY USED AND FOR TRAINING IN
1. DOT NET
2. C sharp
3. ASP
4. VB
5. SQL SERVER
6. JAVA
7. J2EE
8. STRINGS
9. ORACLE
10. VB dotNET
11. EMBEDDED
12. MAT LAB
13. LAB VIEW
14. Multi Sim
CONTACT US
1 CRORE PROJECTS
Door No: 214/215,2nd Floor,
No. 172, Raahat Plaza, (Shopping Mall) ,Arcot Road, Vadapalani, Chennai,
Tamin Nadu, INDIA - 600 026
Email id: 1croreprojects@gmail.com
website:1croreprojects.com
Phone : +91 97518 00789 / +91 72999 51536
RADIAL BASIS FUNCTION PROCESS NEURAL NETWORK TRAINING BASED ON GENERALIZED FR...cseij
For learning problem of Radial Basis Function Process Neural Network (RBF-PNN), an optimization
training method based on GA combined with SA is proposed in this paper. Through building generalized
Fréchet distance to measure similarity between time-varying function samples, the learning problem of
radial basis centre functions and connection weights is converted into the training on corresponding
discrete sequence coefficients. Network training objective function is constructed according to the least
square error criterion, and global optimization solving of network parameters is implemented in feasible
solution space by use of global optimization feature of GA and probabilistic jumping property of SA . The
experiment results illustrate that the training algorithm improves the network training efficiency and
stability.
Improved Timing Estimation Using Iterative Normalization Technique for OFDM S...IJECEIAES
Conventional timing estimation schemes based on autocorrelation experience perfor- mance degradation in the multipath channel environment with high delay spread. To overcome this problem, we proposed an improvement of the timing estimation for the OFDM system based on statistical change of symmetrical correlator. The new method uses iterative normalization technique to the correlator output before the detection based on statistical change of symmetric correlator is applied. Thus, it increases the detection probability and achieves better performance than previously published methods in the multipath environment. Computer simulation shows that our method is very robust in the fading multipath channel.
Exact network reconstruction from consensus signals and one eigen valueIJCNCJournal
The basic inverse problem in spectral graph theory consists in determining the graph given its eigenvalue
spectrum. In this paper, we are interested in a network of technological agents whose graph is unknown,
communicating by means of a consensus protocol. Recently, the use of artificial noise added to consensus
signals has been proposed to reconstruct the unknown graph, although errors are possible. On the other
hand, some methodologies have been devised to estimate the eigenvalue spectrum, but noise could interfere
with the elaborations. We combine these two techniques in order to simplify calculations and avoid
topological reconstruction errors, using only one eigenvalue. Moreover, we use an high frequency noise to
reconstruct the network, thus it is easy to filter the control signals after the graph identification. Numerical
simulations of several topologies show an exact and robust reconstruction of the graphs.
Performance Improvement of Vector Quantization with Bit-parallelism HardwareCSCJournals
Vector quantization is an elementary technique for image compression; however, searching for the nearest codeword in a codebook is time-consuming. In this work, we propose a hardware-based scheme by adopting bit-parallelism to prune unnecessary codewords. The new scheme uses a “Bit-mapped Look-up Table” to represent the positional information of the codewords. The lookup procedure can simply refer to the bitmaps to find the candidate codewords. Our simulation results further confirm the effectiveness of the proposed scheme.
Joint Timing and Frequency Synchronization in OFDMidescitation
With the advent of OFDM for WLAN
communications, as exemplified by IEEE 802.11a, it has become
imperative to have efficient and reliable synchronization
algorithms for OFDM WLAN receivers. The main challenges
with synchronization deal with the frequency offset and delay
spread introduced by the wireless channel. In this paper,
research is done into OFDM timing synchronization and
frequency synchronization techniques.
Intelligent fault diagnosis for power distribution systemcomparative studiesnooriasukmaningtyas
Short circuit is one of the most popular types of permanent fault in power distribution system. Thus, fast and accuracy diagnosis of short circuit failure is very important so that the power system works more effectively. In this paper, a newly enhanced support vector machine (SVM) classifier has been investigated to identify ten short-circuit fault types, including single line-toground faults (XG, YG, ZG), line-to-line faults (XY, XZ, YZ), double lineto-ground faults (XYG, XZG, YZG) and three-line faults (XYZ). The performance of this enhanced SVM model has been improved by using three different versions of particle swarm optimization (PSO), namely: classical PSO (C-PSO), time varying acceleration coefficients PSO (T-PSO) and constriction factor PSO (K-PSO). Further, utilizing pseudo-random binary sequence (PRBS)-based time domain reflectometry (TDR) method allows to obtain a reliable dataset for SVM classifier. The experimental results performed on a two-branch distribution line show the most optimal variant of PSO for short fault diagnosis.
Transmission Time and Throughput analysis of EEE LEACH, LEACH and Direct Tran...acijjournal
This paper gives a brief description about some routing protocols like EEE LEACH, LEACH and Direct
Transmission protocol (DTx) in Wireless Sensor Network (WSN) and a comparison study of these
protocols based on some performance matrices. Addition to this an attempt is done to calculate their
transmission time and throughput. To calculate these, MATLAB environment is used. Finally, on the basis
of the obtained results from the simulation, the above mentioned three protocols are compared. The
comparison results show that, the EEE LEACH routing protocol has a greater transmission time than
LEACH and DTx protocol and with smaller throughput.
Hamming Distance and Data Compression of 1-D CAcsitconf
In this paper an application of von Neumann correction technique to the output string of some
chaotic rules of 1-D Cellular Automata that are unsuitable for cryptographic pseudo random
number generation due to their non uniform distribution of the binary elements is presented.
The one dimensional (1-D) Cellular Automata (CA) Rule space will be classified by the time run
of Hamming Distance (HD). This has the advantage of determining the rules that have short
cycle lengths and therefore deemed to be unsuitable for cryptographic pseudo random number
generation. The data collected from evolution of chaotic rules that have long cycles are
subjected to the original von Neumann density correction scheme as well as a new generalized
scheme presented in this paper and tested for statistical testing fitness using Diehard battery of
tests. Results show that significant improvement in the statistical tests are obtained when the
output of a balanced chaotic rule are mutually exclusive ORed with the output of unbalanced
chaotic rule that have undergone von Neumann density correction.
Hamming Distance and Data Compression of 1-D CAcscpconf
In this paper an application of von Neumann correction technique to the output string of some chaotic rules of 1-D Cellular Automata that are unsuitable for cryptographic pseudo random number generation due to their non uniform distribution of the binary elements is presented.The one dimensional (1-D) Cellular Automata (CA) Rule space will be classified by the time run of Hamming Distance (HD). This has the advantage of determining the rules that have short cycle lengths and therefore deemed to be unsuitable for cryptographic pseudo random number generation. The data collected from evolution of chaotic rules that have long cycles are subjected to the original von Neumann density correction scheme as well as a new generalized scheme presented in this paper and tested for statistical testing fitness using Diehard battery of tests. Results show that significant improvement in the statistical tests are obtained when the output of a balanced chaotic rule are mutually exclusive ORed with the output of unbalanced
chaotic rule that have undergone von Neumann density correction.
Method for Converter Synchronization with RF InjectionCSCJournals
This paper presents an injection method for synchronizing analog to digital converters (ADC). This approach can eliminate the need for precision routed discrete synchronization signals of current technologies, such as JESD204. By eliminating the setup and hold time requirements at the conversion (or near conversion) clock rate, higher sample rate systems can be synchronized. Measured data from an existing multiple ADC conversion system was used to evaluate the method. Coherent beams were simulated to measure the effectiveness of the method. The results show near theoretical coherent processing gain.
IJCER (www.ijceronline.com) International Journal of computational Engineerin...ijceronline
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journal publishing, how to publish research paper, Call For research paper, international journal, publishing a paper, IJCER, journal of science and technology, how to get a research paper published, publishing a paper, publishing of journal, publishing of research paper, research and review articles, IJCER Journal, How to publish your research paper, publish research paper, open access engineering journal, Engineering journal, Mathematics journal, Physics journal, Chemistry journal, Computer Engineering, Computer Science journal, how to submit your paper, peer review journal, indexed journal, research and review articles, engineering journal, www.ijceronline.com, research journals,
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journal of engineering, online Submission
Multi-carrier Equalization by Restoration of RedundancY (MERRY) for Adaptive ...IJNSA Journal
This paper proposes a new blind adaptive channel shortening approach for multi-carrier systems. The performance of the discrete Fourier transform-DMT (DFT-DMT) system is investigated with the proposed DST-DMT system over the standard carrier serving area (CSA) loop1. Enhanced bit rates demonstrated and less complexity also involved by the simulation of the DST-DMT system.
ESTIMATION OF MEDIUM ACCESS CONTROL LAYER PACKET DELAY DISTRIBUTION FOR IEEE ...ijwmn
The most important standard in wireless local area networks is IEEE 802.11. This is why much of the
research work for the enhancement of wireless network is usually based on the behavior of IEEE 802.11
protocol. However, some of the ways in which IEEE 802.11 medium access control layer behaves is still
unreliable to guarantee quality of service. For instance, medium access control layer packet delay, jitter
and packet loss rate still remain a challenge. The main objective of this research is to propose an
accurate estimation of the medium access control layer packet delay distribution for IEEE 802.11. This
estimation considers the differences between busy probability and collision probability. These differences
are employed to achieve a more accurate estimation. Finally, the proposed model and simulation are
implemented and validated - using MATLAB program for the purpose of simulation, and Maple program
to undertake the calculation of the equations.
An Algorithm for Computing Average Packet DelayCSCJournals
Average Packet delay is considered as a vital performance measure for a computer-communication network especially in the network designing problem. Average Packet delay evaluation depends on two main parts: the first part is the capacity of each link in the network, the last one is the flow of each link. The capacity of each link is assumed to be fixed but the flow of each link is computed by using routing algorithms and the traffic requirement matrix. The paper presents an algorithm based on FLOYD’s routing algorithm to calculate the flow of each link and then we can compute the average packet delay.
Variable neighborhood Prediction of temporal collective profiles by Keun-Woo ...EuroIoTa
Temporal collective profiles generated by mobile network users can be used to predict network usage, which in turn can be used to improve the performance of the network to meet user demands. This presentation will talk about a prediction method of temporal collective profiles which is suitable for online network management. Using weighted graph representation, the target sample is observed during a given period to determine a set of neighboring profiles that are considered to behave similarly enough. The prediction of the target profile is based on the weighted average of its neighbors, where the optimal number of neighbors are selected through a form of variable neighborhood search. This method is applied to two datasets, one provided by a mobile network service provider and the other from a Wi-Fi service provider. The proposed prediction method can conveniently characterize user behavior via graph representation, while outperforming existing prediction methods. Also, unlike existing methods that utilize categorization, it has a low computational complexity, which makes it suitable for online network analysis.
Local Model Checking Algorithm Based on Mu-calculus with Partial OrdersTELKOMNIKA JOURNAL
The propositionalμ-calculus can be divided into two categories, global model checking algorithm
and local model checking algorithm. Both of them aim at reducing time complexity and space complexity
effectively. This paper analyzes the computing process of alternating fixpoint nested in detail and designs
an efficient local model checking algorithm based on the propositional μ-calculus by a group of partial
ordered relation, and its time complexity is O(d2(dn)d/2+2) (d is the depth of fixpoint nesting, n is the
maximum of number of nodes), space complexity is O(d(dn)d/2). As far as we know, up till now, the best
local model checking algorithm whose index of time complexity is d. In this paper, the index for time
complexity of this algorithm is reduced from d to d/2. It is more efficient than algorithms of previous
research.
IMPROVING SCHEDULING OF DATA TRANSMISSION IN TDMA SYSTEMScsandit
In an era where communication has a most important role in modern societies, designing efficient
algorithms for data transmission is of the outmost importance. TDMA is a technology used in many
communication systems such as satellites and cell phones. In order to transmit data in such systems we
need to cluster them in packages. To achieve a faster transmission we are allowed to preempt the
transmission of any packet in order to resume at a later time. Such preemptions though come with a delay
in order to setup for the next transmission. In this paper we propose an algorithm which yields improved
transmission scheduling. This algorithm we call MGA. We have proven an approximation ratio for MGA
and ran experiments to establish that it works even better in practice. In order to conclude that MGA will
be a very helpful tool in constructing an improved schedule for packet routing using preemtion with a setup
cost, we compare its results to two other efficient algorithms designed by researchers in the past.
Performance Improvement of Vector Quantization with Bit-parallelism HardwareCSCJournals
Vector quantization is an elementary technique for image compression; however, searching for the nearest codeword in a codebook is time-consuming. In this work, we propose a hardware-based scheme by adopting bit-parallelism to prune unnecessary codewords. The new scheme uses a “Bit-mapped Look-up Table” to represent the positional information of the codewords. The lookup procedure can simply refer to the bitmaps to find the candidate codewords. Our simulation results further confirm the effectiveness of the proposed scheme.
Joint Timing and Frequency Synchronization in OFDMidescitation
With the advent of OFDM for WLAN
communications, as exemplified by IEEE 802.11a, it has become
imperative to have efficient and reliable synchronization
algorithms for OFDM WLAN receivers. The main challenges
with synchronization deal with the frequency offset and delay
spread introduced by the wireless channel. In this paper,
research is done into OFDM timing synchronization and
frequency synchronization techniques.
Intelligent fault diagnosis for power distribution systemcomparative studiesnooriasukmaningtyas
Short circuit is one of the most popular types of permanent fault in power distribution system. Thus, fast and accuracy diagnosis of short circuit failure is very important so that the power system works more effectively. In this paper, a newly enhanced support vector machine (SVM) classifier has been investigated to identify ten short-circuit fault types, including single line-toground faults (XG, YG, ZG), line-to-line faults (XY, XZ, YZ), double lineto-ground faults (XYG, XZG, YZG) and three-line faults (XYZ). The performance of this enhanced SVM model has been improved by using three different versions of particle swarm optimization (PSO), namely: classical PSO (C-PSO), time varying acceleration coefficients PSO (T-PSO) and constriction factor PSO (K-PSO). Further, utilizing pseudo-random binary sequence (PRBS)-based time domain reflectometry (TDR) method allows to obtain a reliable dataset for SVM classifier. The experimental results performed on a two-branch distribution line show the most optimal variant of PSO for short fault diagnosis.
Transmission Time and Throughput analysis of EEE LEACH, LEACH and Direct Tran...acijjournal
This paper gives a brief description about some routing protocols like EEE LEACH, LEACH and Direct
Transmission protocol (DTx) in Wireless Sensor Network (WSN) and a comparison study of these
protocols based on some performance matrices. Addition to this an attempt is done to calculate their
transmission time and throughput. To calculate these, MATLAB environment is used. Finally, on the basis
of the obtained results from the simulation, the above mentioned three protocols are compared. The
comparison results show that, the EEE LEACH routing protocol has a greater transmission time than
LEACH and DTx protocol and with smaller throughput.
Hamming Distance and Data Compression of 1-D CAcsitconf
In this paper an application of von Neumann correction technique to the output string of some
chaotic rules of 1-D Cellular Automata that are unsuitable for cryptographic pseudo random
number generation due to their non uniform distribution of the binary elements is presented.
The one dimensional (1-D) Cellular Automata (CA) Rule space will be classified by the time run
of Hamming Distance (HD). This has the advantage of determining the rules that have short
cycle lengths and therefore deemed to be unsuitable for cryptographic pseudo random number
generation. The data collected from evolution of chaotic rules that have long cycles are
subjected to the original von Neumann density correction scheme as well as a new generalized
scheme presented in this paper and tested for statistical testing fitness using Diehard battery of
tests. Results show that significant improvement in the statistical tests are obtained when the
output of a balanced chaotic rule are mutually exclusive ORed with the output of unbalanced
chaotic rule that have undergone von Neumann density correction.
Hamming Distance and Data Compression of 1-D CAcscpconf
In this paper an application of von Neumann correction technique to the output string of some chaotic rules of 1-D Cellular Automata that are unsuitable for cryptographic pseudo random number generation due to their non uniform distribution of the binary elements is presented.The one dimensional (1-D) Cellular Automata (CA) Rule space will be classified by the time run of Hamming Distance (HD). This has the advantage of determining the rules that have short cycle lengths and therefore deemed to be unsuitable for cryptographic pseudo random number generation. The data collected from evolution of chaotic rules that have long cycles are subjected to the original von Neumann density correction scheme as well as a new generalized scheme presented in this paper and tested for statistical testing fitness using Diehard battery of tests. Results show that significant improvement in the statistical tests are obtained when the output of a balanced chaotic rule are mutually exclusive ORed with the output of unbalanced
chaotic rule that have undergone von Neumann density correction.
Method for Converter Synchronization with RF InjectionCSCJournals
This paper presents an injection method for synchronizing analog to digital converters (ADC). This approach can eliminate the need for precision routed discrete synchronization signals of current technologies, such as JESD204. By eliminating the setup and hold time requirements at the conversion (or near conversion) clock rate, higher sample rate systems can be synchronized. Measured data from an existing multiple ADC conversion system was used to evaluate the method. Coherent beams were simulated to measure the effectiveness of the method. The results show near theoretical coherent processing gain.
IJCER (www.ijceronline.com) International Journal of computational Engineerin...ijceronline
Call for paper 2012, hard copy of Certificate, research paper publishing, where to publish research paper,
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Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
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DCE: A NOVEL DELAY CORRELATION MEASUREMENT FOR TOMOGRAPHY WITH PASSIVE REALIZATION
1. International Journal of Distributed and Parallel Systems (IJDPS) Vol.6, No.2/3, May 2015
DOI:10.5121/ijdps.2015.6301 1
DCE: A NOVEL DELAY CORRELATION
MEASUREMENT FOR TOMOGRAPHY WITH PASSIVE
REALIZATION
Peng Qin1,2
, Bin Dai1
, Benxiong Huang1
and Guan Xu1
1
Department of Electronics and Information Engineering, Huazhong University of
Science and Technology, Wuhan, China
2
China Academy of Electronics and Information Technology, Beijing, China
ABSTRACT
Tomography is important for network design and routing optimization. Prior approaches require either
precise time synchronization or complex cooperation. Furthermore, active tomography consumes explicit
probing resulting in limited scalability. To address the first issue we propose a novel Delay Correlation
Estimation methodology named DCE with no need of synchronization and special cooperation. For the
second issue we develop a passive realization mechanism merely using regular data flow without explicit
bandwidth consumption. Extensive simulations in OMNeT++ are made to evaluate its accuracy where we
show that DCE measurement is highly identical with the true value. Also from test result we find that
mechanism of passive realization is able to achieve both regular data transmission and purpose of
tomography with excellent robustness versus different background traffic and package size.
KEYWORDS
Network Tomography, Delay Correlation Measurement, Passive Realization.
1. INTRODUCTION
Network tomography [1] studies internal characteristics of Internet using information derived
from end nodes. One advantage is that it requires no participation from network elements other
than the usual forwarding of packets while traditional traceroute method needs response to ICMP
messages facing challenge of anonymous routers [2,3].
Many literatures choose delay to calculate correlation between end hosts for tomography.
However, they require either precise time synchronization or complex cooperation. Moreover,
active tomography consumes quantities of explicit probing bandwidth which results in limited
scalability.
In this paper we propose a novel Delay Correlation Estimation approach named DCE with no
need of cooperation and synchronization between end nodes. The greatest property is that we only
need to measure the packet arriving time at receivers. To further reduce bandwidth consumption a
passive mechanism using regular data flow is developed.
We do extensive simulations in OMNeT++ to evaluate its accuracy. Results show that the
correlation of delays 2
, b
a d
d
σ measured by DCE is highly identical with the true value 2
s
σ on
shared path. By altering background traffic and package size we see that passive mechanism has
2. International Journal of Distributed and Parallel Systems (IJDPS) Vol.6, No.2/3, May 2015
2
excellent robustness and is able to achieve regular data transmission as well as purpose of
tomography.
1.1. Contributions
• We propose DCE to estimate delay correlation. This method needs no special cooperation or
synchronization and avoids issues using RTT, making it largely different from prior
tomography tools [4] and [5].
• We develop a passive mechanism for realization, which is efficient for bandwidth saving.
• Extensive simulations in OMNeT++ demonstrates its accuracy and robustness.
2. RELATED WORK
Y. Vardi was one of the first to study network tomography [6] that can be implemented in either
an active or passive way. Active network tomography [7,8,9,10] needs to explicitly send out
probing messages to estimate the end-to-end path characteristics, while passive network
tomography [11,12,13,14] infers network topology without sending any explicit probing
messages.
Article [4]describes delay tomography which however, needs synchronization and cooperation
between sender and receiver. In [5] authors develop Network Radar based on RTT trying to solve
these issues. However, two reasons distort the measurement accuracy. One is due to the variable
processing delay at destination nodes and the other is its violation of a significant assumption that
return paths of packet are uncorrelated while actually they overlaps.
In addition, delay correlation can be further used for topology recovery [15,16], which is
important to improve network performance.
In [17], the concept of DCE was briefly introduced without detailed analysis and evaluation. This
paper includes the full-fledged version of the DEC method together with a comprehensive
analysis of practical cases and experiment results.
3. DELAY CORRELATION ESTIMATION
Figure 1. The tree structure: a sender f and two receivers a,b
3. International Journal of Distributed and Parallel Systems (IJDPS) Vol.6, No.2/3, May 2015
3
A simple model we use in this paper is shown in Fig.1. The routing structure from sender f to
receivers a,b is a tree rooted at f. Otherwise, there is routing loop which must be corrected.
Assume that router s is the ancestor node of both a and b. Assume that the sender uses unicast to
send messages to receivers, and assume that packets are sent in a back-to-back pair. For the k-th
pair of back-to-back packets, denoted as a and b, sent from f to a and b, respectively, we use the
following notations:
• ta(k): the time when a receive ak
in the k-th pair.
• tb(k): the time when b receive bk
in the k-th pair.
• da(k): the latency of ak
along the path from f to a.
• da(k): the latency of bk
along the path from f to b.
• tf(k): the time when f sends the k-th pair of packets.
Using network model of Fig.1 we obtain Eq.(1) for a0
(we start the index with 0 for convenience):
ta(0) = tf(0) + da(0). (1)
Similarly, for ak
, we have
ta(k) = tf(k) + da(k). (2)
Let Eq.(2) − Eq.(1) and δa(k) ≡ta(k) − ta(0). We can obtain Eq. (3) :
δa(k) = (tf(k) − tf(0)) + (da(k) − da(0)). (3)
Denote the time interval between two consecutive pairs of packets as δ. We assume that δ is a
constant for simplicity at this moment, and relax this assumption later. In this case we use
δ
k
kδ ⋅
≡ to replace tf(k)-tf(0) in Eq.3. We then have:
da(k) = δa(k) − kδ + da(0). (4)
Let δ´a(k) ≡δa(k) − kδ. Eq. (4) can be transformed into Eq. (5) :
da(k) =δ´a(k) + da(0). (5)
We can achieve similar result at receiver b as in Eq.(6):
db(k) =δ´b(k) + db(0). (6)
where δ´b(k) ≡ δb(k) − k·δ.
To estimate the correlation between da(k) and db(k), we introduce the following lemma.
Lemma 1. Assume that ζ, η are two random variables, and χ = aζ + b, γ = cη + d, where a,b,c,d are
constants and a,c have the same symbol, thus we have σ2
ζ,η= σ2
χ,γ.
Proof.
γ
χ
γ
γ
χ
χ
σ γ
χ
D
D
E
E
E )
)(
(
2
,
−
−
=
(7)
4. International Journal of Distributed and Parallel Systems (IJDPS) Vol.6, No.2/3, May 2015
4
2
,
2
2
)
)(
(
|
||
|
)
)(
(
)
)(
(
η
ζ
σ
η
ζ
η
η
ζ
ζ
η
ζ
η
η
ζ
ζ
η
ζ
η
η
ζ
ζ
=
−
−
=
−
−
=
−
−
+
−
−
+
=
D
D
E
E
E
D
D
c
a
E
E
acE
D
c
D
a
d
cE
d
c
b
aE
b
a
E
Since da(0) and db(0) can both be regarded as constants in one serial of probing packets, based on
Lemma 1, we have the following theorem:
Theorem 1. The correlation between delay variables da(k) and db(k) is equal to the correlation
between variables δ´a (k) and δ´b(k), which means,
2
)
(
),
(
2
)
(
),
( k
k
k
d
k
d b
a
b
a δ
δ
σ
σ ′
′
= . (8)
Based on the measurements of δ´a (k) and δ´b(k), we can calculate the correlation of delays along
the path from f to a and along the path from f to b, denoted as 2
, b
a δ
δ
σ ′
′ ., using Eq.(9):
∑
=
′
′ ′
−
′
′
−
′
−
=
n
k
b
b
a
a k
k
n
b
a
1
2
, ]
)
(
][
)
(
[
1
1
δ
δ
δ
δ
σ δ
δ . (9)
where δ´a is the sample mean of n
a k 1
k
)
( =
′
δ for i=a,b.
Theorem 2. 2
, b
a δ
δ
σ ′
′ in Eq.(9) is an unbiased estimator of the correlation on shared path.
Proof. First of all we show that 2
,
ˆ b
a d
d
σ (not 2
,
ˆ b
a δ
δ
σ ′
′ ) is an unbiased estimator of the correlation on
shared path (f,s). Let λa λb denote the mean time latency of patha, pathb and let a
d , b
d denote the
sample mean correspondingly; true correlation )]
)
(
)(
)
(
[(
2
, b
b
a
a
d
d k
d
k
d
E
b
a
λ
λ
σ −
−
= To prove
that 2
,
2
, ]
ˆ
[ b
a
b
a d
d
d
d
E σ
σ = we analyze the expectation of )]
)
(
)(
)
(
[( b
b
a
a d
k
d
d
k
d
E −
− :
∑∑
∑
∑
= =
=
=
+
−
−
=
−
−
n
i
n
j
b
a
n
i
b
a
n
i
b
a
b
a
b
b
a
a
j
d
i
d
E
n
k
d
i
d
E
n
i
d
k
d
E
n
k
d
k
d
E
d
k
d
d
k
d
E
1 1
2
1
1
)]
(
)
(
[(
1
)]
(
)
(
[(
1
)]
(
)
(
[(
1
)]
(
)
(
[(
)]
)
(
)(
)
(
[(
(10)
Since delays of the ith
and kth
pair are independent and
b
a
b
a
b
b
a
a
d
d k
d
k
d
E
k
d
k
d
E
b
a
λ
λ
λ
λ
σ −
=
−
−
= )]
(
)
(
[
)]
)
(
)(
)
(
[(
2
,
We obtain Eq. (11)
5. International Journal of Distributed and Parallel Systems (IJDPS) Vol.6, No.2/3, May 2015
5
=
+
≠
=
i
k
i
k
i
d
k
d
E
b
a d
d
b
a
b
a
b
a 2
,
)]
(
)
(
[
σ
λ
λ
λ
λ
(11)
Substituting Eq.(11) into Eq.(10) we obtain
2
,
)
1
(
)]
)
(
)(
)
(
[( b
a d
d
b
b
a
a
n
n
d
k
d
d
k
d
E σ
−
=
−
−
Therefore, 2
,
ˆ b
a d
d
σ is an unbiased estimator of the correlation on shared path as is shown in Eq.(12)
2
,
2
,
1
2
, )
1
(
1
1
)
)
(
)(
)
(
[(
1
1
]
ˆ
[ b
a
b
a
b
a d
d
d
d
n
k
b
b
a
a
d
d
n
n
n
n
d
k
d
d
k
d
E
n
E σ
σ
σ =
−
−
=
−
−
−
= ∑
=
(12)
According to 2
,
2
, b
a
b
a d
d δ
δ
σ
σ ′
′
= in Theorem 1 we prove it.
3.1. Discussion of δ
3.1.1. δ is a constant
A complete delay correlation estimation algorithm (DCE) is summarized in Algorithm 1 if the
time interval δ is a constant.
Algorithm 1 Delay Correlation Estimation Algorithm
Require:
Given the time interval δ
Ensure:
1: for k = 0 : n do
2: Use Eq. (1) to Eq. (3) to measure δa(k) in the k-th transmission;
3: Use δ´a(k) = δa(k)−kδ to calculate δ′a(k) in the k-th loop;
4: Similarly, measure δb(k) and calculate δ´b(k) =δb(k) − kδ;
5: end for
6: With all the values of δ´a(k) and δ´b(k), use Eq.(9) toobtain the correlation 2
, b
a δ
δ
σ ′
′ , which is
equivalent to 2
, b
a d
d
σ between hosts a and b according to Theorem 1.
3.1.2 δ is not a constant
If the time interval δ is not a constant then tf(k) - tf(0) ≠ kδ. In this case using kδ to replace tf(k) -
tf(0) is inappropriate and we choose δf(k) to denote tf(k) - tf(0) in Eq.(3), then Eq.(4) can be
rewritten to Eq.(13).
)
0
(
)
(
)
(
)
( a
f
a
a d
k
k
k
d +
−
= δ
δ . (13)
Correspondingly, Eq.(5) and Eq.(6) can be replaced with δ´a(k) ≡δa(k) − δf(k) and δ´b(k) ≡δb(k)
− δf(k) respectively.
Note that tf(k) is a timestamp contained in the packet, and thus δf(k) = tf(k) − tf(0) is readily
available in practice.
6. International Journal of Distributed and Parallel Systems (IJDPS) Vol.6, No.2/3, May 2015
6
3.2. A mechanism for passive realization
To reduce explicit probing we propose a mechanism for passive realization of Algorithm 1 in real
networks.
Figure 2: The mechanism for passive tomography with source and N end hosts.
As Fig.2 shows passive mechanism works as follows. In practical networks (for example, P2P
networks) if N end hosts request common contents from a source, it will distribute packets. In this
situation source first chooses the No.1 requested data block which is duplicated into packet serial
1 and sent out to all N hosts simultaneously guaranteeing that there exist two successive packets
in a back-to-back manner. An indicator (IR) is needed to tell if the received packet at each host
belongs to the back-to-back pair. If serial of No.1 is sent completely source repeats to the next
until all requested contents are received by N hosts. As regular data flow proceeds transmitting
we change destination address of the current two successive packets when delay correlation
between the corresponding host pair has been measured (if number of packets sent to them with
indicator IR reaches τ, where τis a tunable threshold).
One may naturally raise two questions: first is which two successive packets in one serial are
chosen to add an IR? while the other is how to guarantee that in each transmission the two
successive packets are in a back-to-back manner? A simple solution can address both of them.
The basic idea is that we divide packets into small size. This can satisfy both the need of back-to-
back and regular data transmission. In fact our experiment results show that any two successive
packets in a serial distributed to N hosts can be chosen to add IR as long as the time interval δ is
appropriate.
3.3. Arrangement of IR
Based on above argument that each successive pair of packets can be regarded as back-to-back, in
one transmitting serial at most N-1 delay correlations are measured (shown on top of Fig.3). After
N-1 times switching of destination addresses and IRs all delay correlations between N hosts can
be obtained.
7. International Journal of Distributed and Parallel Systems (IJDPS) Vol.6, No.2/3, May 2015
7
In this way the complexity is only O(N) compared with O(N2) to measure N(N−1)/2 correlations.
Figure 3: Arrangement of IR. IRi,j in each serial indicates blocks destined to i, j should be successive.
4. SIMULATION RESULTS
4.1. Dynamic Network Tomography
We use OMNeT++ for simulations [18] to demonstrate the correctness and robustness of passive
DCE tomography. We generate a network shown in Fig.4. Nodes of BG are randomly and
dynamically selected for producing background traffic while others are the source and client
nodes. When two client nodes a, b request contents from source node f, it sends regular data in a
back-to-back manner. In this case route algorithm determines a multicast tree with root f and
leaves a, b.
Figure 4: Structure for DCE test
We set packet size hundreds of bytes to satisfy both regular transmission and back-to-back
property. One advantage is that since it is smaller than Maximum Transmission Unit (MTU) we
avoid delay for package segmentation. We set bandwidth of each link value of 100Mbps; the
8. International Journal of Distributed and Parallel Systems (IJDPS) Vol.6, No.2/3, May 2015
8
background traffic pattern conforms to the Poisson distribution, whose expectation value could be
set from 1MBps to 12MBps. We also change the size of packet from 100 bytes to MTU to see its
influence on DCE measurement.
4.2. Results
Using DCE methodology we set τto be 1550 and observe over 1500 timing samples for receiver
pair.
Figure 5: One way trip time latency on patha, pathband shared path (f,s)
Fig.5 depicts the one way trip latency in our environment. One example of the average delay on
patha, pathb and shared path are 0.6526ms, 0.5478ms and 0.4317ms respectively. In some case
errors may happen to the timestamp as the variation of background traffic. Therefore, we ignore
packets beyond twice the average delay on each path.
Figure 6: DCE measurement covariance
2
, b
a δ
δ
σ ′
′ versus the directly measured delay variance on the shared
path (f,s)
9. International Journal of Distributed and Parallel Systems (IJDPS) Vol.6, No.2/3, May 2015
9
Fig.6 shows the DCE covariance 2
, b
a δ
δ
σ ′
′ versus true value 2
s
σ on shared path (f,s) with different
packet size. Value 2
, b
a δ
δ
σ ′
′ is calculated using the arriving time of package at a,b while 2
s
σ is
calculated directly from delay on (f,s). According to Theorem 1 we know that 2
, b
a d
d
σ is equal to
2
, b
a δ
δ
σ ′
′ thus, ideally 2
, b
a δ
δ
σ ′
′ and 2
s
σ should be identical and fall onto the 45 degree line. Taking
test result with package size of 800 Bytes for example we see the estimated value is always
locating nearby the true value with slight difference which demonstrates the correctness of DCE
tomography. If we change size of data packet from 100 bytes to MTU, delay correlations
measured by DCE are always desired. This demonstrates that passive mechanism is able to
achieve both data transmission and tomography.
Figure 7: 2
2
2
,
s
s
b
a
σ
σ
σ δ
δ −
′
′
: DCE measurement error versus different background traffic
To see its robustness with different background traffic, in Fig.7 packet size is fixed to be MTU. In
this case performance of DCE tomography is perfect with the percentage error below 4% when
the expectation value of background traffic is within the region [1.25MBps,7.5MBps]. However,
when it increases to 8MBps, error percentage increases sharply. This is because in this situation
network's performance becomes worse and some shared paths between higher level routers are
congested heavily, which destroys the back-to-back property of packets. Note that when the
expectation value of background traffic is relatively small (below 1MBps) delay correlation
caused by queuing on routers will not be significant thus the performance also degrades.
5. CONCLUSIONS AND FUTURE WORK
In this paper we propose a novel tomography method named DCE to estimate delay correlation
with no need of synchronization and cooperation between end hosts. We also develop the passive
mechanism to further save bandwidth. Extensive simulations demonstrate the correctness of DCE.
Moreover, passive realization is able to achieve both purpose of tomography and data
transmission with excellent robustness versus different background traffic and package size.
In future, we plan to utilize the DCE measure for topology inference and implement it in practical
network environment.
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ACKNOWLEDGEMENTS
This work was supported by the National Key Technology Research and Development Program
of the Ministry of Science and Technology of China under Grant no.2012BAH93F01, the
Innovation Research Fund of Huazhong University of Science and Technology, no. 2014TS095
and the National Sciece Foundation of China under Grant no. 60803005.
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Authors
Peng Qin received the B. S. Degree in Electronics and Information Engineering from
Huazhong University of Science and Technology, Wuhan, P. R. China, in 2009. His
research interests are in the areas of network tomography, network measurement, p2p
network and applications of network coding.
11. International Journal of Distributed and Parallel Systems (IJDPS) Vol.6, No.2/3, May 2015
11
Bin Dai received the B. Eng, the M. Eng degrees and the PhD degree from Huazhong
University of Science and Technology of China, P. R. China in 2000, 2002 and 2006,
respectively. From 2007 to 2008, he was a Research Fellow at the City University of Hong
Kong. He is currently an associate professor at Department of Electronics and Information
Engineering, Huazhong University of Science and Technology, P. R. China. His research
interests include p2p network, wireless network, network coding, and multicast routing.
Benxiong Huang received the B. S. degree in 1987 and PhD degree in 2003 from
Huazhong University of Science and Technology, Wuhan, P. R. China. He is currently a
professor in the Department of Electronics and Information Engineering, Huazhong
University of Science and Technology, P. R. China. His research interests include next
generation communication system and communication signal processing.
Guan Xu received the B.S. degree in Electronics and Information Engineering from
Huazhong University of science and technology, Wuhan, P. R. China, in 2008. He is
currently a PhD Candidate in the Department of Electronics and Information Engineering
at the Huazhong University of science and technology. His research interests are in the
areas of practical network coding in P2P network, IP switch networks and SDN networks
with emphasis on routing algorithms and rate control algorithms.