With the increasing number of end users that are using multimedia services, demand for access network high-bitrate systems with sufficient quality of services is also increasing. However, this might not always be ensured by telecom operators, as they must optimize networks according to the Quality of Service (QoS) and multimedia data transmission. In this work, we tested Gigabit Passive Optical Network (GPON) performance with the help of various tools (iPerf, RFC 6349 or ITU-T Y.1564). The Grafana software v7.3.3 tool is used to monitor data streams. Measurements were made to limit the downstream bitrate of up to 20 end users at 1 Gbit/s, 500 Mbit/s, 300 Mbit/s and 100 Mbit/s. Based on repeated measurements, an aggregation curve was modelled, indicating the available bitrate with respect to the network load.

Gigabit-Capable Passive Optical Network (GPON) reach extension using optical amplification is well established, yet validation of user-facing service performance at the Optical Network Terminal (ONT) Ethernet interface remains limited. This paper addresses this gap by experimentally validating a distributed, circulator-separated reach extender based on two Semiconductor Optical Amplifiers (SOAs) in a controlled laboratory testbed, comparing a passive 50 km baseline with a 60 km reach-extended link. Service performance was assessed at the ONT Ethernet interface using RFC 6349 TCP throughput testing and ITU-T Y.1564 Ethernet service activation testing, with values reported as medians from 10 independent runs. Internet Protocol Television (IPTV) quality was evaluated using estimated Mean Opinion Score—Video (MOS-V) and Estimated Peak Signal-to-Noise Ratio (EPSNR) for H.264 and MPEG-2 streams. The 60 km configuration preserved upstream TCP throughput while reducing downstream throughput from 765.650 to 721.900 Mbit/s. Median latency increased from 1.336 to 1.408 ms, jitter decreased from 0.076 to 0.057 ms, and video-profile frame loss increased from 0 to approximately 0.0064. MOS-V values remained predominantly in the good range. The results indicate feasible 60 km GPON operation with measurable downstream and loss-related trade-offs, providing repeatable service-level validation beyond optical-budget-only reporting rather than introducing a new optical reach-extender architecture.

There has been a huge increase in the number of mobile devices over the past few years. Many mobile users own more than one mobile device. Compared to conventional laptops, mobile devices are constantly active and their users use them outdoors more often than personal computers. Compared to desktop computers, mobile devices accompany their owners on their travels and therefore there is a significant risk of tracking and eavesdropping on user data without a user being aware of it. This paper describes techniques how the attacker could track users by using the Wireless Fidelity (Wi-Fi) network. Every mobile device generates traffic that can be divided into “Automatic” and “User”. When” Automatic” traffic is generated, the device can be found because of its pattern. The paper also describes how the attacker can get into the victim's Wi-Fi network without being in its range. When breaching the Wi-Fi network security, the attacker can connect to the victim's network during his first appearance in range of this network. Security pre-cautions and possible directions of future work are discussed at the end of this paper.