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With the rapid advancement of internet technology, the demand for network performance continues to grow. Due to the problems of low fault tolerance and limited available bandwidth of traditional single-path transmission methods, multipath transmission has received widespread attention. However, existing multipath transmission schemes may encounter problems such as packet disorder and mutual interference between paths when facing complex network environments, thus reducing network transmission efficiency. This paper proposes a multipath reliable transmission scheme (FC-MPRT) based on fountain codes and recurrent neural networks (RNNs) to address these challenges. The scheme fully leverages the randomness and reliability of fountain codes to effectively solve the buffer-blocking problem caused by frequent packet loss retransmissions and the requirement for packets to arrive in order. Additionally, a supervised prediction scheme based on RNN is designed at the data receiving end to mitigate the potential resource wastage problem during encoding and decoding. The transmission efficiency is significantly enhanced by predicting the arrival of packets. We evaluate the performance of FC-MPRT in various network scenarios on NS-3 and Mininet platforms. Simulation results demonstrate that FC-MPRT achieves a 66.1% improvement in throughput and a 47.6% reduction in the average block transmission delay compared to existing multipath transmission schemes. [ABSTRACT FROM AUTHOR]

In 5G, users can easily enjoy services by accessing the edge devices (EDs) deployed around the base stations. Generally, due to the uneven distribution and mobility of users, one ED is required to serve multiple users simultaneously, that results in the ED overload, seriously affecting the quality of experience (QoE) of the users. By responding to users' requests, service migration realizes the cross edge device migrations, that dynamically provides services for mobile users, which effectively improves the resource utilization rate of edge servers and the QoE of users. However, during the service migrations, malicious users may deploy pseudo base stations, gateways and other devices to illegally eavesdrop or tamper with user service data, that causes user information loss or disclosure. To prevent these security issues, a fountain-coding based cooperative jamming strategy is proposed in this paper. Specifically, the fountain coding technology is introduced to construct a three-node transmission model, including an original node, a target node and a malicious node, to realize the secure data transmission process in service migration. Besides, a group of relay nodes are employed to carry out cooperative jamming, that deteriorate the illegal eavesdropping quality of malicious nodes on service data. Then secrecy rate and outage probability are utilized to evaluate the security and reliability of the whole service migration. Finally, the theoretical analysis is shown by simulation results. [ABSTRACT FROM AUTHOR]

Ensuring content security and copyright protection is a critical concern in wireless communication networks. Furthermore, the emergence of services demanding high-band width and very low delay such as online Games, extended reality (XR), Metaverses, etc., Non-Orthogonal Multiple Access (NOMA) is a technology with the potential to enhance the spectral efficiency of fifth-generation (5G) wireless network and beyond. Hence, this paper studies a NOMA-based downlink system that employs intelligent reconfigurable surfaces (IRS) and operates in a physical-layer security environment. Our study also incorporates the utilization of Fountain codes (FCs), all while contending with the presence of a malicious eavesdropper. Furthermore, a cooperative jamming technique is employed to degrade the quality of the eavesdropping channel. The main contribution of this paper is to derive precise closed-form expressions of outage probability (OP), energy efficiency (EE), intercept probability (IP), and average secrecy rate (ASR) for the proposed system. We also develop a Deep Neural Network (DNN) model to evaluate OP, IP, ASR and the average number of time slots (ATS). Subsequently, Monte Carlo simulations are presented as a means to validate the theoretical findings. The simulation results yield the following insights: i) Their primary purpose is to validate the analytical formulas. ii) This research significantly contributes to deepening our understanding of IRS-NOMA systems, providing a foundation for future investigations into practical implementations. iii) We investigate the optimal power allocation factors within the IRS-NOMA framework, offering valuable insights into designing IRS-NOMA systems to achieve reliable and secure communication. iv) The results illustrate the superior performance of IRS-NOMA in comparison to the conventional IRS-Orthogonal Multiple Access (OMA) method.

ABSTRACTThe performance of broadcasting networks employing Fountain codes with receiver diversity techniques is investigated in the present work. Particularly, we derive the closed-form expressions of the cumulative distribution function (CDF), the probability mass function (PMF), and the raw moments of the number of the needed time slots to deliver a common message to all users under two diversity schemes, namely, maximal ratio combining (MRC) and selection combining (SC). Numerical results are supplied to verify the accuracy of the considered networks and highlight the behaviours of these metrics as a function of some vital parameters such as the number of receivers, and the number of received antennae. Additionally, we also confirm the advantages of the MRC scheme compared with the SC scheme in the broadcasting networks.

The performance of broadcasting networks employing Fountain codes with receiver diversity techniques is investigated in the present work. Particularly, we derive the closed-form expressions of the cumulative distribution function (CDF), the probability mass function (PMF), and the raw moments of the number of the needed time slots to deliver a common message to all users under two diversity schemes, namely, maximal ratio combining (MRC) and selection combining (SC). Numerical results are supplied to verify the accuracy of the considered networks and highlight the behaviours of these metrics as a function of some vital parameters such as the number of receivers, and the number of received antennae. Additionally, we also confirm the advantages of the MRC scheme compared with the SC scheme in the broadcasting networks. [ABSTRACT FROM AUTHOR]

The performance of the satellite-terrestrial network with Fountain Codes (FCs) is conducted in the present work. More precisely, the air-to-ground link is modeled according to the shadow-Rician distribution to capture the strong line-of-sight (LOS) path as well as the impact of the shadowing. As a result, we employ the directional beamforming at both the satellite and relay to mitigate such an ultra-long transmission distance. We investigate the trade-off between the reliability and security aspects. Particularly, we derive the outage probability (OP) and intercept probability (IP) in the closed-form expressions. To further facilitate the security of the considered networks, the friendly jamming scheme is deployed as well. Finally, simulation results based on the Monte-Carlo method are given to corroborate the exactness of the developed mathematical framework and to identify key parameters such as antenna gain, and transmit power that have a big impact on the considered networks. [ABSTRACT FROM AUTHOR]

The comprehensive performance of cognitive broadcasting networks employing Fountain codes (FC) and maximal ratio transmission (MRT) is investigated in the present paper. More precisely, the secondary transmitter (ST) employs Fountain code to effectively broadcast a common message such as a safety warning, security news, etc., to all secondary receivers (SRs) via underlay protocol of cognitive radio networks (CRNs). Different from works in the literature that are interested in studying the outage probability (OP), and the ergodic capacity of the CRNs. The present paper, on the other hand, focuses on the characteristics of the number of needed time slots to successfully deliver such a message. Particularly, we derive in closed-form expressions the cumulative distribution function (CDF), the probability mass function (PMF), and the average number of the required time slot to broadcast the message to all SRs. Additionally, we also provide the throughput of secondary networks (SNs). We point out the impact of some key parameters, i.e., the number of SRs and the number of transmit antennae at the secondary transmitter, on the performance of these considered metrics. Numerical results via the Monte-Carlo method are given to verify the accuracy of the derived framework as well as to highlight the influences of some essential parameters. Furthermore, we also compare the performance of the proposed networks with state-of-the-art and simulation results unveiling that the considered system consistently outperforms works in the literature.

In wireless communication wiretap channel, for the eavesdropper to obtain the legitimate receiver decoding rules situation, this paper proposes a LT-SLT fountain code anti-eavesdropping channel coding design. This method targets the Luby Transform (LT) code transmission for some of the original symbols of the Shifted LT (SLT) code and utilizes the fountain code to receive the correct symbols in different noise channels with differential characteristics so that the decoding process of the eavesdropper changes and cannot be decoded in synchronization with the legitimate receivers, and then the partial symbols of the recovered source are different from those of the legitimate receivers. When these symbols continue to participate in SLT decoding, increasing the untranslated rate of the eavesdropper. Experimental results show that although the method proposed in this paper increases the number of decoded symbols by a small amount, the eavesdropper untranslated rate of this scheme gets improved by about 15% when the main channel or the wiretap channel is varied individually, compared with LT code and SLT code. When both the main channel and the wiretap channel are varied simultaneously, the untranslated rate of the eavesdropper in this scheme gets approximately 30% higher compared to LT code and SLT code, and the untranslated rate of the eavesdropper in this scheme gets approximately 14% higher compared to SLT-LT fountain code. When the main channel is worse or slightly better than the wiretap channel, the untranslated rate of eavesdroppers of this scheme is better than that of SLT-LT fountain code, which effectively ensures secure transmission of information.

The performance of the satellite-terrestrial network with Fountain codes (FCs) is conducted in the present work. More precisely, the air-to-ground link is modeled according to the shadow-Rician distribution to capture the strong light-of-sight (LOS) path as well as the impact of the shadowing. As a result, we employ the directional beamforming at both the satellite and relay to mitigate such an ultra-long transmission distance. We investigate the trade-off between the reliability and security aspects. Particularly, we derive the outage probability (OP) and intercept probability (IP) in the closed-form expressions. To further facilitate the security of the considered networks, the friendly jamming scheme is deployed as well. Finally, simulation results based on the Monte-Carlo method are given to corroborate the exactness of the developed mathematical framework and to identify key parameters such as antenna gain, and transmit power that have a big impact on the considered networks.

The comprehensive performance of cognitive broadcasting networks employing Fountain codes (FC) and maximal ratio transmission (MRT) is investigated in the present paper. More precisely, the secondary transmitter (ST) employs Fountain code to effectively broadcast a common message such as a safety warning, security news, etc., to all secondary receivers (SRs) via underlay protocol of cognitive radio networks (CRNs). Different from works in the literature that are interested in studying the outage probability (OP), and the ergodic capacity of the CRNs. The present paper, on the other hand, focuses on the characteristics of the number of needed time slots to successfully deliver such a message. Particularly, we derive in closed-form expressions the cumulative distribution function (CDF), the probability mass function (PMF), and the average number of the required time slot to broadcast the message to all SRs. Additionally, we also provide the throughput of secondary networks (SNs). We point out the impact of some key parameters, i.e., the number of SRs and the number of transmit antennae at the secondary transmitter, on the performance of these considered metrics. Numerical results via the MonteCarlo method are given to verify the accuracy of the derived framework as well as to highlight the influences of some essential parameters. Furthermore, we also compare the performance of the proposed networks with state-of-the-art and simulation results unveiling that the considered system consistently outperforms works in the literature. [ABSTRACT FROM AUTHOR]

This paper introduces a Simulink model design for a modified fountain code. The code is a new version of the traditional Luby transform (LT) codes. The design constructs the blocks required for generation of the generator matrix of a limited-degree-hopping-segment Luby transform (LDHS-LT) codes. This code is especially designed for short length data files which have assigned a great interest for wireless sensor networks. It generates the degrees in a predetermined sequence but random generation and partitioned the data file in segments. The data packets selection has been made serialy according to the integer generated from both degree and segment generators. The code is tested using Monte Carlo simulation approach with the conventional code generation using robust soliton distribution (RSD) for degree generation, and the simulation results approve better performance with all testing parameter. [ABSTRACT FROM AUTHOR]

In recent years, physical layer security technology has provided a new way to solve the problem of secure transmissions in wireless communications from an information theory perspective by using physical layer security coding and the inherent characteristics of the channel. As a nonsystematic code, Luby transform (LT) code has the characteristics of random coding and rateless, therefore, eavesdroppers cannot directly obtain useful information from leaked code symbols. As a shifted LT (SLT) code, the SLT codes can efficiently recover information, with a smaller decoding overhead. Therefore, we propose an SLT-LT joint code anti-eavesdropping scheme based on random symbol sets. Based on the environment of the main channel, the sender selects a set of random symbols to send to legitimate receivers as known symbols and uses these random symbols and message symbols to form source symbols for the SLT-LT concatenated coding to increase the bit error rate (BER) of the eavesdroppers. The experimental results show that, compared with other anti-eavesdropping LT schemes, our proposed scheme only adds a small amount of decoding overhead but has a better security performance.

Utilizing fountain codes to control the peak-to-average power ratio (PAPR) is a classic scheme in Orthogonal Frequency Division Multiplexing (OFDM) wireless communication systems. However, because the robust soliton distribution (RSD) produces large-degree values, the decoding performance is severely reduced. In this paper, we design statistical degree distribution (SD) under a scenario that utilizes fountain codes to control the PAPR. The probability of the PAPR produced is combined with RSD to design PRSD, which enhances the smaller degree value produced. Subsequently, a particle swarm optimization (PSO) algorithm is used to search the optimal degree value between the binary exponential distribution (BED) and PRSD distribution according to the minimum average degree principle. Simulation results demonstrate that the proposed method outperforms other relevant degree distributions in the same controlled PAPR threshold, and the average degree value and decoding efficiency are remarkably improved. [ABSTRACT FROM AUTHOR]

Distributed fountain coding plays an important role in rateless code research. The reliability and effectiveness of these coding schemes are increasingly challenged with the growing applications. In this paper, a novel multiple-access network with cooperative relay is presented, and a novel enhanced distributed fountain coding scheme for this network is proposed. The overall degree distributions are derived, and the asymptotic decoding performance is analyzed theoretically by employing the And-Or tree method. On this basis, a design method using joint iterative optimization algorithms is proposed to optimize the degree distributions of the sources and relays. Simulation results show that the proposed enhanced distributed fountain codes outperform the existing generalized distributed fountain codes (GDFC) and have a good performance on both lossless and lossy channels. It reveals that the proposed codes can provide unequal error protection (UEP) property for different sources by introducing the extra cooperative relay. The performance improvement is not restricted to the sources connected to the cooperative relay but applies to all sources. With the additional relay, the proposed codes are able to overcome the effects of bad channel conditions caused by terrain, obstacles, and so on, to avoid communication interruptions and improve the reliability of the network. [ABSTRACT FROM AUTHOR]

To reduce recovery cost of repairing multiple failed nodes, many repair schemes have been proposed for erasure codes based distributed storage systems. However, most of the existing researches ignore the network topology of storage devices. Motivated by such considerations, we combine delay repair schemes with network topology and propose a tree-structured model based on fountain codes with large value of (n, k, r) to improve the repair efficiency. More precisely, with the consideration of network topology, a new target named data recovery cost is defined to measure the efficiency of coded fragment download and source file reconstruction, and then the optimal recovery threshold is derived to minimize the average data recovery cost of general tree-structured model. Moreover, we analyze and compare the average data recovery cost of general tree-structure with different systematic parameters. To further improve the data transmission efficiency, an optimal tree-structured scheme based on improved tabu search algorithm (ITSAORT) is proposed. Compared with other algorithms, the ITSA-ORT scheme uses Prim algorithm to generate the initial solution and then uses special method to obtain the corresponding neighborhood structure. The experimental results show that the proposed scheme can find a globally optimal solution and obtain lower cost of data recovery. In addition, the ITSA-ORT scheme has lower computational complexity than the optimal tree-structured scheme based on particle swarm optimization algorithm (PSO-ORT) and the optimal tree-structured scheme based on firefly algorithm (FA-ORT).

Long-range wide-area network (LoRaWAN) is an energy-efficient and inexpensive networking technology that is rapidly being adopted for many Internet-of-Things applications. In this study, we perform extensive measurements on a new LoRaWAN deployment to characterise the spatio-temporal properties of the LoRaWAN channel. Our experiments reveal that LoRaWAN frames are mostly lost due to the channel effects, which are adverse when the end-devices are mobile. The frame losses are up to 70 percent, which can be bursty for both mobile and stationary scenarios. Frame losses result in data losses since the frames are transmitted only once in the basic configuration. To reduce data losses in LoRaWAN, we design a novel coding scheme for data recovery called DaRe that works on the application layer. DaRe combines techniques from convolutional and fountain codes. By implementing DaRe, we show that 99 percent of the data can be recovered with a code rate of 1/2 when the frame loss is up to 40 percent. Compared to the repetition coding scheme, DaRe provides 21 percent higher data recovery and can save up to 42 percent of the energy consumed on a transmission for 10-byte data units. We also show that DaRe provides better resilience to bursty frame losses. [ABSTRACT FROM AUTHOR]

Summary: In this paper, we investigate the performance of caching schemes based on fountain codes in a heterogeneous satellite network. We consider multiple cache‐aided hubs, which are connected to a geostationary satellite through backhaul links. With the aim of reducing the average number of transmissions over the satellite backhaul link, we propose the use of a caching scheme based on fountain codes. We derive a simple analytical expression of the average backhaul transmission rate and provide a tight upper bound on it. Furthermore, we show how the performance of the fountain code‐based caching scheme is similar to that of a caching scheme based on maximum distance separable codes. [ABSTRACT FROM AUTHOR]

Fountain codes are rateless erasure codes that have initially been designed for multicast and streaming applications. They provide dynamic code rates which are defined by the channel conditions. Subsequently, fountain codes have also demonstrated their benefits for transmissions over wireless channels. With fountain codes, feedback channel deployment can be reduced which could reduce collisions in half-duplex systems. Contrary to previous research on fountain codes that focused on defining the theoretical bound of code rate and complexity, in this paper, we would like to put them into practice by extending their performance evaluation in two other aspects. First, we would like to investigate the implementation process of fountain codes in a real-world deployment including header analysis, packet layout investigation as well as implementation cost. Next, contrary to previous works that aim at defining code rate after decoding completion, in this work, we would like to focus on the partial decoding capabilities of fountain codes. This metric could be used for performance evolution for transmissions over degraded channel conditions found in the wireless applications. We discussed and compared in this paper several types of fountain codes including LDPC, LT, Raptor, etc. [ABSTRACT FROM AUTHOR]

Ensuring low energy consumption is a crucial issue in underwater communications, since battery replacement may be difficult and expensive in these scenarios. We analyze in this paper the energy consumption of a multi-hop underwater acoustic network (UWAN) employing fountain codes. Moreover, in order to reduce this energy consumption we optimize the modulation order assuming differential phase-shift keying ($M$ -DPSK), as well as the number of hops. We investigate the required number of fountain-encoded packets for different modulation orders. Our results show that, by optimizing the modulation order, the number of hops and the number of fountain packets, we can obtain important energy savings, especially for long distances. In addition, with the proposed scheme the energy consumption decreases significantly compared to the case without fountain codes, reaching up to 40% of savings.

This paper evaluates intercept probability (IP) of a cooperative cognitive radio network. Using Fountain codes, a secondary source continuously generates encoded packets, and sends them to secondary destination and relay nodes that attempt to receive a sufficient number of the encoded packets for recovering the source data. If the relay can sufficiently collect the packets before the destination, it replaces the source to transmit the encoded packets to the destination. Also in the secondary network, a passive eavesdropper attempts to illegally receive the packets sent by the source and relay nodes, and if it can accumulate enough encoded packets, the source data is intercepted. To enhance secrecy performance, in terms of IP, a cooperative jammer is used to transmit noises on the eavesdropper. We also propose a simple transmit power allocation method for the secondary transmitters such as source, relay and jammer so that outage performance of a primary network is not harmful. We derive an exact closed-form expression of IP over Rayleigh fading channel, and verify it by performing Monte-Carlo simulations.

Internet of Mobile Things (IoMTs) refers to the interconnection of mobile devices, for example, mobile phones, vehicles, robots, etc. For mobile data, strong extra processing resources are normally required due to the limited physical resources of the mobile devices in IoMTs. Due to latency or bandwidth limitations, it may be infeasible to transfer a large amounts of mobile data to remote server for processing. Thus, distributed computing is one of the potential solutions to overcome these limitations. We consider the device mobility in IoMTs. Two situations of the movement position of the mobile devices, i.e., unpredictable and predictable, are considered. In addition, three possible relative positions between the two server sets which respectively correspond to the positions of a mobile device for computation tasks offloading and for output results receiving, i.e., within the same server sets, with two different server sets and with two adjacent server sets, are studied. Coded schemes with high flexibility and low complexity are proposed based on Fountain codes to reduce the total processing time and latency of the distributed fog computing process in IoMTs for the above different situations. The latency related performance, i.e., the computation, the communication and the transmission loads, is analyzed. We also compare of the Fountain code-based and the uncoded schemes and numerical results demonstrate that shorter total processing time and lower latency can be achieved by the Fountain code-based schemes. [ABSTRACT FROM AUTHOR]

Abstract Degree distribution plays a great role in the performance of Luby transform codes. Typical degree distributions such as ideal soliton distribution and robust soliton distribution are easy to implement and widely used. Nevertheless, their adaptabilities are not always outstanding in various code lengths, especially in the case of short length. In this paper, our work is to optimize degree distributions for the short-length LT codes by using swarm intelligence algorithm, considering its conceptual simplicity, high efficiency, flexibility, and robustness. An optimization problem model based on sparse degree distributions is proposed in the first place. Then, a solution on the basis of an enhanced chicken swarm optimization algorithm, termed as ECSO, is designed for the problem. In ECSO, substitution of bottom individuals, revision of chicks’ update equation, and introduction of differential evolution are designed to enhance the ability of optimization. Simulation comparisons show that the proposed solution achieves much better performance than two other swarm intelligence-based solutions.

In this paper, we propose new serial decoding of Luby transform (LT) codes over additive white Gaussian noise channels. LT encoder generates a potentially limitless number of encoded packets, and the decoder incrementally collects the packets to ensure successful recovery of the information. In the proposed algorithm, the newly coming code nodes are the first to pass the messages, and it is their neighboring source nodes that will receive these input messages and update their output messages; then, the next neighboring code nodes that have not been covered are to be included in the updating group; in this greedy way, the message propagation is conducted from neighbors to neighbors. The analysis demonstrates that the proposed algorithm has a faster convergence speed than the conventional ones, and simulation shows that it has an effective bit error rate performance.

Radio blackout due to a plasma sheath during reentry has attracted much attention over several decades. However, radio blackout has long puzzled the aerospace industry and has not yet been completely resolved. A communication method based on adaptive classification fountain code is proposed to improve the transmission reliability of important information during a spacecraft's reentry. According to the deterioration of the plasma sheath channel, the classification parameters of the source information are adjusted to protect the most important information. This method allows the reliable transmission of the most important information. The deterioration of the communication quality of the plasma sheath channel is detected from the voltage standing wave ratio of the transmitting antenna in real time. The simulation results show that the transmission reliability of important information almost doubles when using the transmission method of adaptive classification fountain code. In contrast to the traditional communication method, the proposed method can be applied to TT&C (telemetry, tracking, and command) and communication of reentry vehicles and near-space hypersonic vehicles in the future, reducing the interruption time of communication blackout.

Cloud storage has gained increasing attention from the industry and research communities with concerns about data stored in cloud computing environments, despite its many advantages. The reasons come from economic viability to the latency along with behavioral changes that may affect the applications that use data stored remotely. Among those challenges, there is the problem of ensuring the integrity and retrievability of users' data in the cloud. Several schemas have been proposed: proof of data possession (PDP), proof of retrievability (PoR), and proof of ownership (PoW) that differ on the approach to guarantee the effective retrieval of data stored remotely. In this paper, a novel PoR protocol is proposed: hyper-scalability, availability, and integrity layer (Hy-SAIL), where a new PoR scheme adds higher availability to data stored and a flexible manner to perform integrity checks. It is demonstrated that Hy-SAIL leads to an efficient and scalable cryptographic system that meets near-optimal bounds in terms of communication and storage complexities. It is also proposed a new adversarial model that aggregates the main functionalities of a realistic adversary in cloud computing environments. Hy-SAIL operates on data that are not affected by any kind of incremental change or update, which is the characteristic of various file types stored in clouds, such as stored video and audio streams. When compared to other systems, such as HAIL, Hy-SAIL is more scalable and efficient. The results collected with an unoptimized implementation of Hy-SAIL point to a better perspective than other approaches.

In this paper upper and lower bounds on the probability of decoding failure under maximum likelihood decoding are derived for different (nonbinary) Raptor code constructions. In particular four different constructions are considered; (i) the standard Raptor code construction, (ii) a multi-edge type construction, (iii) a construction where the Raptor code is nonbinary but the generator matrix of the LT code has only binary entries, (iv) a combination of (ii) and (iii). The latter construction resembles the one employed by RaptorQ codes, which at the time of writing this article represents the state of the art in fountain codes. The bounds are shown to be tight, and provide an important aid for the design of Raptor codes. [ABSTRACT FROM AUTHOR]

In this article, a novel class of fountain codes with feedback, called relative-entropy-based fountain (REF) codes, is proposed. The transmitter of REF codes adapts the degrees of encoded symbols to make the degree distribution at the receiver close to the robust soliton distribution, where the distance between two distributions is measured by relative entropy. The proposed REF codes are shown to achieve excellent intermediate performance over binary erasure channels (BECs), and binary-input additive white Gaussian noise channels (BI-AWGNCs) for both unicast, and multicast scenarios. For multicast, a non-uniform input symbol selection scheme is proposed to enhance the performance of REF codes. Furthermore, since the feedback is imprecise under noisy channels, the concept “belief” is introduced to improve the reliability of REF codes. Theoretical analysis is performed for the proposed REF codes, with an upper bound, and an approximate lower bound of the intermediate performance of REF codes over BECs derived. Both theoretical analysis, and simulations show that the proposed REF codes outperform the state-of-the-art fountain codes with feedback, in terms of the intermediate performance, with low overhead. [ABSTRACT FROM AUTHOR]

In this paper, a new class of online fountain codes is proposed to provide high intermediate symbol recovery rates (ISRRs) with low overhead. The encoder consists of two phases. In the first phase, a zigzag decodable online fountain (ZDOF) is proposed to provide a high ISRR. We utilize the characteristics of zigzag decodable codes so that the online fountain codes start decoding in the first phase without having to wait for the receipt of symbols of degree one. In the second phase, the buffer decoding method (BDM) is proposed to utilize a buffer to hold discarded symbols so as to generate useful symbols and improve the decoding performance. In addition, we provide a theoretical analysis based on random graph theory to analyze the performance of the proposed scheme. The theoretical analysis and simulation results show that the proposed scheme outperforms conventional online fountain codes, and that the buffer size does not have to be large. [ABSTRACT FROM AUTHOR]

This paper compares the end-to-end (E2E) fountain codes and random linear network coding (RLNC) for lossy multi-hop short-packet communications, under the constraint that the coding coefficient overhead imposed by RLNC recoding is non-negligible. The decoding failure probability (DFP) of RLNC is analyzed and computed as a function of the most relevant parameters. A DFP minimization problem is formulated and numerically solved from a cross-layer perspective. By comparing the codes using optimized parameters, the DFP of RLNC is shown to be higher than that of the E2E codes, which is due to the coefficient overhead. The results suggest that E2E fountain codes might be preferred for multi-hop short-packet communications. [ABSTRACT FROM AUTHOR]

Summary: In order to correct and avoid channel error, fountain codes were the best solution by limiting feedback channels and reducing energy consumption. Multi‐hops transmission is the principal limitation of the deployment and the use of these codes. Indeed, relayed transmission conducts to the generation of useless data, named overflow leading to a waste of energy, the most critical issue, and the big challenge in WSN. In this paper, based on a clustered architecture and estimation, we consider a distributed estimation scheme composing of sensor members and the cluster head. In order to reduce the number of a useless encoded packet generated as well as the impact of the overflow, we determine the optimal minimal number of encoded packets needed for data decoding. Sensor observations are encoded using fountain codes, and then messages are collected at the cluster head where a final estimation is provided within learning method. Then messages are collected at the cluster head where a final estimation is provided with a classification based on Bayes rule. The main goal of this paper is to determine the number of encoded packets by exploiting the classification model for fountain data estimation to minimize the overflow and extend the network lifetime. [ABSTRACT FROM AUTHOR]

With the explosive growth of multimedia data, Enterprise Multimedia Security (EMS) is a serious matter to maintain enterprise information security. As the rise of social media applications triggers higher bandwidth demand and shorter end-to-end delay requirements, edge computing has emerged as a promising technique to reduce delay. Edge servers are often deployed around mobile devices via a one-hop wireless network connection. However, migrating multimedia data over wireless networks to edge servers for edge computing is vulnerable to eavesdroppers. Ensuring the security of enterprise multimedia data in the edge computing is a top priority. To cater for the data security over wireless transmisson for edge computing, window-based fountain codes, is treated as a feasible technology to compensate this gap. Based on the characteristics of the fountain codes, data security over wireless transmisson is implemented only when the target receiver accumulates enough coding packets in advance of the eavesdropper. In the general wireless transmission, the eavesdropper receives data packets or not depends on whether the wireless channel lose packets. To ensure data security, we introduce the constellation-rotation technique and interfering noise into wireless signal which can disturb the eavesdropper's signal quality and increase the packet loss in the eavesdropper. Specifically, we study how to partition the video streaming into windows, which takes the end-to-end delay into consideration while guaranteeing lower intercept probability which indicates the probability video data is leaked to the eavesdropper. [ABSTRACT FROM AUTHOR]

In this paper, we propose a rateless, three-stage, two-way multiply-and-forward (MF) relaying system over the Rayleigh flat fading channel, where two source nodes communicate with each other through a relay node and all nodes work on half-duplex and time-division mode. We thoroughly analyze the signals during all three stages in the proposed MF system and derive the closed-form symbol error rate (SER) expressions for an uncoded MF-two-way relay network (MF-TWRN). Furthermore, we provide the equivalent point-to-point fading channel model, which is employed to carry out the asymptotic performance analysis. We finally put forth an optimization model for the MF-TWRN with fountain codes. Simulation results show that our optimized degree distribution can provide outstanding performance for the MF-TWRN compared to those in the literature. [ABSTRACT FROM AUTHOR]

In this paper, a transmission redundancy optimization strategy for fountain codes that uses an adaptive filtering technique as well as recent results concerning the upper bound of the source packet erasure probability for fountain codes over finite fields is proposed. The performance of the proposed strategy was evaluated in static and simulated realistic underwater acoustic channel environments simulated by a recently proposed statistical underwater acoustic channel model. The goal of this investigation is to improve the communication efficiency of underwater acoustic sensor networks that use communication protocols based on fountain codes. The performance of the proposed strategy is compared with the recently proposed approaches of discrete stochastic approximation (DSA) and the joint power and rate control (JPR) schemes. The simulation results demonstrate that the strategy proposed in this paper performs better than the existing schemes in both static and simulated realistic environments. The proposed strategy is 4.75 times better than the DSA in the static convergence performance evaluation. Further analysis shows that in the presence of a simulated realistic environment, compared to DSA and JPR, the strategy proposed in this paper reduces the overall transmission redundancy by approximately 11.4% and 52.6%, respectively. It also improves the average communication efficiency by 1.3% and 12.5%, respectively. The average optimization error relative to optimal redundancy is improved by approximately 62.1% and 92.5%, respectively. These numerical results are obtained by employing the specific simulation parameters and the simulated environment mentioned in this paper.

The transmission of video files in Vehicular Adhoc Networks (VANETs) has become very prevalent as commuters prefer video data during travel. The delay with which the data is received becomes very significant as video packets received after their scheduled deadlines become useless. The performance of the network may significantly be reduced on such packet drops especially with mobile networks. This work aims at the reduction of end to end delay of video packets by applying the two techniques- Network Coding (NC) and RaptorQ (RQ) codes. The techniques are implemented in four VANET scenarios and an extensive analysis is done by varying the packet sizes during the transmission of three files of various sizes. The End to End Delay (EED) and Packet Delivery Ratio (PDR) are measured and plotted for all scenarios. The results show the influence of packet size on these parameters considered and the suitability of the techniques applied. The observations also show that RQ proves better for smaller files and NC suits better when the file size increases.

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Machine learning is an effective technique for big data analytics. We focus on the study of big data analytics with decentralized learning in large-scale networks. Fountain codes are applied to the decentralized learning process to reduce communication load for exchanging intermediate learning parameters among fog nodes. Two scenarios, i.e., disjoint datasets and overlapping datasets, are analyzed. Comparison results show that communication load can be reduced significantly by the Fountain-based scheme for large-scale networks, especially when the quality of communication links is relatively bad and/or the number of fog nodes is large. [ABSTRACT FROM AUTHOR]

In this letter, we propose an efficient encoding scheme for 3GPP Raptor codes. When encoding numerous information blocks with the same size, conventional encoder is similar to matrix multiplication in the first stage of the encoding. The main idea of the proposed method is to utilize the potential redundancy in the multiplication. A series of ordered operation instructions, stored in a variable called ${\it\text { Index}}$ , are established to achieve the goal. To construct ${\it\text { Index}}$ , two schemes are introduced in this letter. Analysis demonstrates that the proposed schemes have less complexity than the conventional one. Furthermore, the simulation results show that both of them take less than 1/3 the encoding time of the original method. [ABSTRACT FROM AUTHOR]