Throughput Loss Research Articles

AN EXPERIMENTAL TESTBED PERFORMANCE EVALUATION FOR VEHICULAR AD HOC NETWORK (VANET)

Vehicular ad hoc networks (VANETs) are essential components of a smart city environment owing to some safety-enhancing applications. The use of VANETs extends from safety applications such as accident warning and collision avoidance to entertainment applications such as streaming video or comfort applications such as parking spot identification. Besides, these applications require interconnecting, for example, by enabling vehicles to communicate with other vehicles. Thus, the flow of information between different vehicles requires implementing a suitable transmission route. This paper aims to use VANETs to empower vehicle-to-vehicle (V2V) and V2I communication through a network that does not need infrastructure. In this paper, we propose to utilize proactive routing protocols such as OLSR, BATMAN, and BABEL and present their performance via a developed testbed. The performance is compared based on two different positionings, multi-hop, and full mesh, using metrics such as throughput and packet loss. The proposed approach demonstrates that BABEL outperforms both the OLSR and BATMAN in both positionings. This research highlights the need to select the appropriate routing protocol for VANETs and evaluate their performance, which will be significant for widespread deployment.

Experimental Connectivity Analysis for Drones in Greenhouses

This study aims to explore the communication capabilities for video crucial applications of two commercial drones—the Parrot AR.Drone 2.0 and the Parrot Anafi—in a greenhouse environment. Experiments were conducted on Received Signal Strength (RSS), Round-Trip Time (RTT) and the throughput on 802.11n at the 2.4 GHz network. From the experiments, it was found that none of the UAVs have an isotropic radiation pattern. Indoor measurements close to the roof and the ground were more prone to signal degradation. Even though the RTT of the Parrot Anafi was higher than that of the AR.Drone 2.0, the Anafi in almost all cases managed to achieve higher throughput and lower path loss, proving its superiority for video application. In addition, the maximum distance that the Parrot Anafi could fly in the greenhouse without any video quality loss was 110 m, while the AR.Drone 2.0 was hardly able to reach 30 m. Finally, the effect of the propellers has an insignificant impact on the UAV connection characteristics in all tested scenarios.

Investigating the Degradation of EUV Transmittance of an EUV Pellicle Membrane.

The extreme ultraviolet (EUV) pellicle is a freestanding membrane that protects EUV masks from particle contamination during EUV exposure. Although a high EUV transmittance of the pellicle is required to minimize the loss of throughput, the degradation of EUV transmittance during the extended exposure of the pellicle has been recently reported. This may adversely affect the throughput of the lithography process. However, the cause of this phenomenon has not yet been clarified. Therefore, we investigated the cause of the degradation in the EUV transmittance by observing the compositional change when the Ru/SiNx pellicle composite was heated in an emulated EUV scanner environment. The Ru thin film that was deposited at high pressure had more void networks but was not oxidized, whereas the SiNx thin film was oxidized after heating. This was because the void network in the Ru thin film served as a preferential diffusion path for oxygen and caused oxidation of the SiNx thin film. It was confirmed that the degradation of the EUV transmittance was due to the oxidation of SiNx. The results verified the effect of diffusivity in the thin film due to the void network on oxidation and EUV transmittance.

Analisis Quality of Service Jaringan Wireless untuk Teknologi Streaming

Wireless network services can be known for their quality with the Quality of Service (QoS) method. This method can measure the quality of streaming services in terms of throughput, delay, packet loss, and jitter. The purpose of this study was to analyze wireless network QoS for streaming technology. This type of research is quantitative with observation methods using the Wireshark application and compared with TIPHON standards. The target of the ICONNET ISP wireless survey on Jalan Nusantara km. 13 Tanjungpinang Timur District. The parameters for measuring QoS use four parameters, namely throughput, delay, packet loss, and jitter. Our findings show that the throughput of obtaining index value is 3.67 and is at a good level. Furthermore, the delay value has an average index of 4 with the best level. Meanwhile, the jitter obtained an index value of 3 at a good level, while the packet loss value obtained an index of 3.3 and had a good level. Based on the results of this study, the quality of ICONNET ISP wireless network services when accessing streaming technology shows data speed instability, data delays, and lost data packets. However, the network quality is still in the "Good" level in terms of throughput, jitter, and packet loss parameters, and the "Best" level in terms of the delay parameter.

Novel Group Mobility Model for Software Defined Future Mobile Networks

Nowadays, a massive amount of data leads to cause network traffic and inflexible mobility in future mobile networks. A new Group Mobility Model (GMM) named MoMo is introduced that addresses the issue of the aforementioned problems. Even though, software defined network (SDN) is functional with network-rooted mobility protocols that enhance the network efficiency. Some existing network-rooted mobility administration methods still undergo handover delay, packet loss, and high signaling cost through handover processing. In this research work, SDN-based fast handover for GMM is proposed. Here, the neighbor number of evolving node transition probabilities of the mobile node (MN) and their obtainable resource probabilities are estimated. This makes a mathematical framework to decide the preeminent number of the evolving nodes and then allot these to mobile nodes virtually with all associations finished by the exploit of Open-Flow tables. The performance examination demonstrates that the proposed SDN rooted GMM technique has the enhanced performance than the conventional handover process and further technique by handover latency, signaling cost, network throughput, and packet loss.

Next-generation active telescope for space astronomy

We present a design for an active telescope for space astronomy. The telescope is capable of both exoplanet work and general astronomy over wavelengths from ∼100 nm up to 5 μm. The primary mirror is 6 m in diameter, formed by 16 mirror segments that are precisely phased and supported on rigid body actuators and with segment optical surface figures fine-tuned using surface figure actuators. The active primary forms a large deformable mirror (DM) with wavefront error (WFE) correction at the entrance pupil. Thus the largest source of WFE can be removed at the source and is corrected over the entire field of view. This enables diffraction-limited performance at 400 nm and a more efficient optical system over a broader wavelength range than could be achieved by a small DM at a downstream relayed pupil. The telescope is passively cooled to below 100 K at Sun–Earth L2, enabling astronomical-background-limited observations out to 5 μm. Launched on a SpaceX Starship or alternatively National Aeronautics and Space Administration’s Space Launch System, the telescope requires minimal deployments. A 72-m-diameter starshade provides a contrast ratio better than 10 − 10 for exoplanet science. Near the visible region, with a 108% working bandwidth from 300 to 1000 nm, a working distance of 120 Mm provides a 51-mas inner working angle (IWA). This band can be moved to shorter or longer wavelengths by adjusting the starshade range from the telescope. Our first-ever thermal analysis of such a starshade shows that a temperature below 100 K can be achieved over a broad range of observing directions, permitting the possibility of working into the infrared. We model the yield in exoplanets that can be observed. A starshade and associated spectrograph offer significant advantages for exoplanet characterization. They enable a much broader instantaneous spectral bandwidth (here 108%) than current coronagraphs (∼10 % to 20% bandwidth), allow both polarizations to be observed simultaneously, and have higher throughput. The IWA is twice as small as can be achieved with a coronagraph and there is no outer working angle. These differences are particularly pronounced in the UV, where coronagraph performance would be strongly affected by throughput losses, wavefront aberrations, Fresnel polarization effects at surfaces, and thermal instability.

Analysis And Implementation of Simple Queue and Queue Tree Methods For Optimizing Bandwitdh Management

This study analyzes the Simple Queue method with Queue tree using a Mikrotik Router to perform Bandwidth management. Both of these methods will be tested using the parameters of Quality of Services ( QOS ), namely throughput, delay, jitter and packet loss. The results of the analysis of the Quality of Services will be compared with weighting based on the TIPHON standard, then the results of the analysis will be tested using the wireshark application . The results of the analysis of these two methods, the Simple Queue method is more suitable because it gets a higher value based on the TIPHON standard. Therefore it is recommended to use Bandwidth management using the Simple Queue method

Real-time Wi-Fi network performance evaluation

<span>The most critical parameters that indicate the Wi-Fi network are throughput, delay, latency, and packet loss since they provide significant benefits, especially to the end-user. This research aims to investigate Wi-Fi performance in an indoor environment for light-of-sight (LOS) and non-light-of-sight (NLOS) conditions. The effect of the surrounding obstacles and distance has also been reported in the paper. The parameters measured are packet loss, the packet sent, the packet received, throughput, and latency. Site measurement is done to obtain real-time and optimum results. The measured parameters are then validated using the EMCO ping monitor 8 software. The comparison results between the measurement and the simulation are well presented in this paper. Additionally, the measurement distance is done up to 30 meters and the results are reported in the paper as well. The results indicate that the throughput value decreases with an increasing distance, where the lowest throughput value is 24.64 Mbps and the highest throughput value is 70.83 Mbps. Next, the maximum latency value from the measurement is 79 ms, while the lowest latency value is 56.09 ms. Finally, this research verified that obstacles and distances are among the contributing factors affecting the throughput and latency performance of the Wi-Fi network.</span>

Performance Evaluation of VoIP Service for Emergency Disaster Responses over WiMAX-WLAN Integrated Network

As a very large archipelago country, Indonesia has a high intensity of the natural disaster. In many cases, the telecommunication infrastructure collapse during the disaster. Therefore, a prominent and robust emergency telecommunication network is required. In this paper, an implementation of VoIP services over the WiMAX-WLAN integrated network is proposed. The integrated network is designed to provide an alternative of the emergency network during the disaster response. The VoIP service is selected for the study case because this service can be used as a complementary of the telephony service. In this paper, the WiMAX network is designed based on the IEEE Standard 802.16-2004 with the frequency band of 3.5 GHz while the WLAN network is designed based on the IEEE Standard 802.11n. To support many scenarios of network topology, the proposed integrated network is designed in P2P and PMP topologies. Within these network topologies, the network performance is evaluated in terms of delay, jitter, throughput and packet loss, as well as MOS value. The network performance is evaluated over various background traffic. From the experimental evaluation, it shows that the network becomes worse when the network load that is represented by the background traffic exceeding 3 Mbps. In general, there is no significant performance different between P2P and PMP network topology.

DSOQR: Deep Reinforcement Learning for Online QoS Routing in SDN-Based Networks

With the rapid development of mobile communication technology, there are an increasing number of new network applications and services, and the existing best-effort routing algorithms cannot meet the quality-of-service (QoS) requirements of these applications and services. QoS-routing optimization solutions based on a software-defined network (SDN) are often targeted at specific network scenarios and difficult to adapt to changing business requirements. The current routing algorithms based on machine learning (ML) methods can generally only handle discrete, low-dimensional action spaces and use offline network data for training, which is not effective for dynamic network environments. In this study, we propose DSOQR, which is an online QoS-routing framework based on deep reinforcement learning (DRL) and SDN. DSOQR collects network status information in real time through the software-defined paradigm and carries out on-policy learning. Under this framework, we further propose SA3CR, which is a QoS-routing algorithm based on SDN and asynchronous advantage actor-critic (A3C). The SA3CR algorithm can dynamically switch routing paths that meet the conditions according to the current network status and the needs of different service types to ensure the QoS of target traffic. Experimental results show that DSOQR is effective and that the SA3CR algorithm has better performance in terms of delay, throughput, and packet loss rate.

Strategies to reduce the extent of product dilution in a tandem simulated-moving-bed process for ternary separation without loss of throughput

One of highly-efficient separation processes for recovery of a target product in the pharmaceutical and fine chemical industries is a simulated-moving-bed (SMB) process. Although an SMB can ensure high separation capability and high throughput, it always has a problem of product dilution, which increases the energy consumption for post-processing of SMB product streams. This issue is even more important in a tandem SMB, which uses two subordinate SMB units in series for implementing a ternary-separation task. To address this issue, we sought to develop effective strategies for reducing the extent of product dilution in a tandem SMB without loss of throughput. For this task, a standing-wave-design (SWD) method was used to find a clue to reducing the extent of a tandem-SMB product dilution, which revealed the following results. First, for the considered issue, it could be effective to increase the column length of the SMB unit under the influence of column-efficiency limiting factor while decreasing the column length of the other SMB unit accordingly for the purpose of keeping total bed volume constant. It could also be effective to place more columns in the zones containing both edges of solute band for a target component. The two aforementioned strategies (called “S1” and “S2” respectively) were applied to the tandem SMB for recovery of neoagarotetraose from neoagarooligosaccharides. It was found that when the S1 method was utilized, the extent of product dilution in the tandem SMB was reduced by 56%. Furthermore, if the S1 and S2 methods would be used together, the extent of the tandem-SMB product dilution could be reduced by up to 85%. It is thus expected that the proposed strategies can contribute to a substantial improvement in the energy efficiency for post-processing of product stream from a tandem SMB process for ternary separation.

DDS-XRCE Standard Performance Evaluation of Different Communication Scenarios in IoT Technologies

Although the increasing number of technological products brings many solutions for Internet of Things (IoT) applications, it also causes some drawbacks, such as whether the product in question would run accordingly to a system structured to enable high-performance like Data Distribution Service (DDS). Therefore, the capabilities of the products must be defined to say that they are compatible enough. This paper aims to evaluate the performance of the DDS-XRCE standard while observing its working mechanism. As test scenarios, we benefit from three DDS-XRCE deployments that occurred due to the kind of receiver and sender, the path that packets follow, and the protocols used. Test conditions were set by switching stream modes, transport profiles, and limiting packet deliveries. We obtained the test environment by creating the DDS and DDS-XRCE objects using several eProsima implementations and tools for the standards. We monitored the network messages in two ways: 1) Using multiple Gnome Terminator terminals for observation via the human eye during testing. 2) Using Wireshark to save the information of the packets for further examination. We conducted 36 experiments focusing on latency, throughput, and packet loss. As a result of our study, the DDS-XRCE standard is deemed suitable for Internet of Things applications.

Handover Approach for Heterogeneous Networks with Improved K-Partite Graph

Vertical handovers (VH) is said to be a significant effect of user mobility in a diverse wireless network as it causes a major effect on network performances, like call blocking probability, packet delay, or throughput. On the other hand, the analysis of VH meets a lot of complexities when it comes to investigation, including network modeling that was very complex owing to the diversity in topology. This article aims to present a VH method by means of graph theory. At first, the improved k-partite graph is exploited to model the VH issues in HetNets. Second, improved Dijkstra’s algorithm (DA) is deployed for choosing the best path. Further, the analytic hierarchy process is used for estimating the adaptive weights among nodes. Accordingly, optimal selection of weights in DA is performed depending on a hybridized model named as grey wolf upgraded CSO. Ultimately, several metrics such as throughput, packet jitter, and delay and packet losses indicate that the created strategy is efficient.

Performance analysis of breadth-first search and depth-first search on MANET for health monitoring system

The development of mobile ad-hoc network (MANET) technology is increasing and is directly proportional to the need. MANET is a wireless network consisting of several nodes moving freely and without using the infrastructure. MANET can be applied in various fields such as the military, natural disasters, and health services. The health sector, especially the health monitoring system, gets more attention because it involves maintaining patient safety. However, wireless devices installed in health services have not been able to reach patients. This condition causes the required time and energy consumption to increase. Therefore, the breadth-first search (BFS) and depth-first search (DFS) methods are indispensable in determining the quality of service (QoS) in MANET. QoS parameters analyzed include packet delivery ratio (PDR), throughput, packet loss, delay, and energy consumption. This study aims to choose a health data traffic route that can improve QoS when transmitting data. The simulation results using the 2018 version of MATLAB show that BFS has a better performance than DFS on delay and energy consumption parameters. Meanwhile, DFS has better performance than BFS on PDR, throughput, and packet loss parameters.

Concurrent size

The size of a data structure (i.e., the number of elements in it) is a widely used property of a data set. However, for concurrent programs, obtaining a correct size efficiently is non-trivial. In fact, the literature does not offer a mechanism to obtain a correct (linearizable) size of a concurrent data set without resorting to inefficient solutions, such as taking a full snapshot of the data structure to count the elements, or acquiring one global lock in all update and size operations. This paper presents a methodology for adding a concurrent linearizable size operation to sets and dictionaries with a relatively low performance overhead. Theoretically, the proposed size operation is wait-free with asymptotic complexity linear in the number of threads (independently of data-structure size). Practically, we evaluated the performance overhead by adding size to various concurrent data structures in Java−a skip list, a hash table and a tree. The proposed linearizable size operation executes faster by orders of magnitude compared to the existing option of taking a snapshot, while incurring a throughput loss of 1%−20% on the original data structure’s operations.

ICRP: Internet-Friendly Cryptographic Relay-Detection Protocol

Traffic hijacking over the Internet has become a frequent incident over the last two decades. From minor inconveniences for casual users to massive leaks of governmental data, these events cover an unprecedently large spectrum. Many hijackings are presumed to be caused by unfortunate routing mistakes, but a well-organized attacker could set up a long-term stealthy relay, accessing critical traffic metadata, despite suitable encryption schemes. While many studies focus on the mitigation of known attacks, we choose to design a complete detection method regardless of the attacker’s strategy. We propose a two-party cryptographic protocol for detecting traffic hijacking over the Internet. Our proposal relies on a distance-bounding mechanism that performs interactive authentication with a “Challenge–Response” exchange, and measures the round-trip time of packets to decide whether an attack is ongoing. Our construction is supported by worldwide experiments on communication time between multiple nodes, allowing us to both demonstrate its applicability and evaluate its performance. Over the course of this paper, we demonstrate our protocol to be efficient—itrequires only two cryptographic operations per execution inducing negligible workload for users and very few loss of throughput, scalable—no software updates are required for intermediate network nodes, routing protocol independent—this means that any future update of the route selection process will not induce changes on our scheme, and network friendly—the added volume of transiting data is only about 1.5%.

Stable routing protocol for unmanned aerial vehicle ad‐hoc networks based on DQN‐OLSR

In unmanned aerial vehicle ad-hoc network (UANET), the network topology changes with time due to the movement of the unmanned aerial vehicles (UAVs), which brings great challenges to the design of the routing protocol. In traditional routing protocols, when UANET topology changes, nodes cannot dynamically update neighbour nodes and topology information, and routing table calculation cannot accurately reflect the actual transmission path. As a result, network cannot meet the quality of service (QoS) requirements such as low end-to-end delay, high throughput and low packet loss rate. This paper proposes a dynamically optimized link state routing (OLSR) protocol based on Deep Q-Network algorithm (DQN-OLSR). In this protocol, each node first adjusts the sending interval of Hello messages adaptively in real time, according to the position and speed information of its neighbour nodes. Then the protocol uses the DQN algorithm to dynamically adjust the flooding interval of topology control (TC) messages to improve the routing update capability of nodes. The simulation verifies that the UANETs under this protocol have higher throughput and less packet loss rate than ad-hoc on-demand distance vector (AODV), grid routing protocol (GRP) and OLSR protocols, at different movement speeds in random waypoint (RWP) and random walk mobile models. Under nomadic as well as pursue mobile models, DQN-OLSR performs consistently with OLSR QoS performance, with the best performance among all four protocols. By further adding positioning errors to the nodes, it shows that the proposed protocol has good robustness, and the QoS performance degradation keeps within a low level.

Performance Evaluation of MPTCP on Simultaneous Use of 5G and 4G Networks.

The 5G cellular network comes with a promise to provide a very high data rate at low latency, which is becoming critical for advancing technologies. Mobile operators are currently deploying the 5G cellular network worldwide. However, because of limited coverage and high susceptibility of the 5G network to obstacles, handoffs from 5G to 4G and vice versa frequently occur, especially when the user equipment (UE) is moving. These handoffs often cause significant delays in data transmission due to packet losses and retransmissions. A promising solution can be to use both 4G and 5G networks simultaneously, which can solve this problem and yield a better throughput. Multipath transmission control protocol (TCP) is an effective solution for this problem, but it requires significant performance evaluation before practical deployment. In this study, we implement an MPTCP testbed based on NS3-DCE that enables to test the performance of MPTCP schedulers and congestion control algorithms (CCAs) in both 3GPP and non-3GPP networks. Through extensive simulation experiments in a scenario where a UE simultaneously utilizes both 4G and 5G networks, we found that blocking estimation (BLEST) scheduler implemented with balanced linked adaptation (BALIA) CCA can produce the highest throughput and lowest delay. Finally, we showed how received signal to interference and noise ratio (SINR), congestion window, throughput, and packet losses are interconnected.

COMPARISON ANALYSIS PERFORMANCE OF SYNOLOGY NAS AND XIGMANAS WITH RAID CONFIGURATION

<em>This research is to find out which NAS performance is the best in handling file delivery with RAID configuration, the methods needed in this test include transfer rate parameters, CPU and Memory resource usage, and QoS which includes throughput, delay, and packet loss by uploading and testing. download with variations in different file capacities. The results showed that synology is better in the transfer rate parameters of both RAID configurations, both upload and download, with the delivery of variations in file capacity delivery with an average transfer rate of 116-118MBps, and xigmanas 97-118MBps. In the resource usage parameter, the percentage of resource usage in both RAID configurations with testing upload or download xigmanas is lower with CPU usage 22%, memory usage 1.4-1.5GB or 30%, compared to synology CPU 30-34%, with CPU usage memory 190-201MB or about 42%. On the parameters of QoS throughput xigmanas 780-930Mbit/s, and Synology >800Mbit/s (standard >75% very good) from both upload and download RAID configurations. The average delay of both servers is 0.03ms (standard <150ms is very good), and packetloss is 0 (standard 0% is very good) on both servers from upload and download tests. QoS results from both servers are in very good category according to TIPHON standards</em>

An Enhanced Software Framework for Improving QoS in IoT

Internet of Things (IoT) and Artificial Intelligence (AI) with its subcomponents are the latest emerging technologies that make our daily lives easier. Quality of Service (QoS) plays a very important role in IoT due to the large number of interconnected nodes. QoS is inversely dependent on the node count, i.e. the increment of nodes causes hampering to QoS, as increasing the number of nodes increases the number of requests to the IoT server. An enhanced framework is strongly needed to control QoS in IoT applications. This study proposes and implements an enhanced framework using Matlab, to control the number of requests. The proposed model can improve QoS parameters like throughput, latency, and packet loss by reducing the number of requests generated by the end nodes without compromising the services to the end user. The results showed that QoS parameters improved in terms of throughput by 5-10%, packet loss by up to 6%, and packet latency by 4%. This model can also be tested in hardware and may provide a better QoS solution.