Abstract. The aim of this paper is to determine the performance enhancement of the network
for eliminating congestion through the use of the benefits of algorithms. These algorithms can
be used in hindering the congestion which may occur within the network that relies on a
Transmission Control Protocol (TCP) protocol. This paper specifically focuses on
demonstrating the function of TCP, and most especially the four (slow start, congestion
avoidance, fast retransmit and fast recovery algorithms) that are applied in the control of
congestion. In the study, the varying effects of connection link from PPP DS1 to PPP DS3 on
the network’s performance are investigated.

Abstract— A wireless sensor network (WSN) has
significant applications such as monitoring the far
environmental and target tracking. This has been enabled
by the sensors that are smaller, cheaper, and intelligent.
These sensors are equipped with wireless interfaces that can
communicated with each other to form a network. The
design of a WSN depends significantly on the application,
and it must consider factors such as the environment, the
application’s design objectives, costs, hardware, and
system constraints. However, the nodes closer to the sink
in the network are overburdened with huge traffic loading
known as hot spot problem as the data from the total region
are forwarded through them to reach the sink node. As a
result, their energy gets consumed quickly and the network
is subdivided in to multiple region. This paper aims to study
the grid based random clustering and grid based static
clustering techniques in WSN and to evaluate the
performance and compare between them by via simulation.
The results show that grid based static clustering
outperforms random clustering in term of throughput by
22%, reduces energy consumption by 30%, and increase
residual energy by 20%. Thus, the network lifetime of the
WSN will be prolonged.

ABSTRACT
Article history:
Received May 13, 2019
Revised Jun 14, 2019
Accepted Jul 28, 2019
As the rapid growth of multimedia application over the Internet, it is essential to preserve the Quality of Service (QoS), which is certifying the guaranteed service through the Internet and representing the biggest challenges for the current IP based services. Multimedia traffic usage has been increased in relation to the streaming media such as video conferencing using OPNET, the performance can be simulated based on heavy and light scenarios for video conferencing including web traffic. The overall WLAN load data are obtained for such scenarios, also the performance of simulated overall Delay in the three scenario networks is measured.

ABSTRACT
Article history:
Received April 27, 2021
Revised Jul 15, 2021
Accepted Aug 4, 2021
Radio over fiber (RoF) can be assessed as a system of most convenient combination of optical fiber and radio signals. The technique of orthogonal frequency division multiplexing (OFDM) considers as a data distribution over a huge number of carriers having spaced from each other with specific frequencies at overlap bands. Hence incorporates OFDM with the optical fiber, OFDM-RoF system can be increased the modulation RF access capacity besides high-speed data transmission, it considers a broadband communication trend of the current and future applications specifically for 5G mobile. The optical network scenarios of various RF can be model with optisystem software, and OFDM in addition to use a section of the orthogonal multiplex frequency of 16-quadrature amplitude modulation (QAM) RF modulating signal. In the optical domain, Mach-Zehnder modulator (MZM) optical modulators are used to carry out different results with different fiber lengths. An OFDM-RoF wireless communication system considers as advanced data rate transmission achievement by minimum delays. The essential goal of this paper is for identifying the minimum bit error rate (BER) for the 16-QAM modulation with varying fiber length. The OFDM-RoF system can be able for realizing a fiber length 100 km with a restricted decreasing in the received power so that the constellation noise is became greater despite of applying electrical amplification and optical amplification.

ABSTRACT
Article history:
Received Jul 3, 2021
Revised Aug 25, 2021
Accepted Sep 3, 2021
Photovoltaic (PV) panels have drawback of having their peak power reduced when clouds or shade are present. Furthermore, it is only available while the sun shine. Nearby structures, plants, bird droppings, and other obstacles shade operating photovoltaic (PV) devices, effectively reducing the incident solar radiation produced by the modules. When these PV panels are exposed to partial shading, their power efficiency is reduced. A neural network with a kind of artificial neural network is used in the suggested hybrid method (ANN). The key focus of this article is to use environmental effects dependent on partial shading to get the maximum performance from a solar system. The suggested hybrid solution is tested in the MATLAB/Simulink working platform using partial shading test cases, and the efficiency is compared to other approaches. Additionally, the best options for the suggested procedure, current, voltage, and power are examined.

Abstract: