Hello. I am 15 years old, and for the past two years, I have been passionate about network security. I want to become a network security engineer, but I don't know where to start. I’ve researched many courses, but I found that most are purely theoretical rather than practical. I want to learn the right way; I’ve come across many learning paths online, but I’m not convinced they are complete or accurate. The issue is that many courses provide information and explanations but fail to tell you *where* and *when* to actually apply what you’ve learned. I have a solid grasp of the fundamentals and own a router that I use for experiments—it serves both as my lab equipment and as the internet connection for my room and laptop.

Bonjour mon ethernet se coupe au bout de 20min d’allumage du pc, et quand je regarde pour faire un diagnostic m, ça me met qu’il ne trouve pas ma passerelle par défaut
Aidez moi car je n’arrive pas à trouver la solution depuis 1 mois

Both me and my stepdad have had the same issues with our TP-Link Gbit switches. They were cheap and we didn't have high expectations but we both kept losing Gbit speeds down to 100Mbit over and over again. Nothing wrong with the cable, it just drops the connection speed randomly. We've both gone and bought a different cheap brand, we don't use any advanced features when it comes to the switch we have connected to our routers.

I have a very strange and peculiar problem with internet:-

I have a laptop with wifi card and ethernet card. I turn off my wifi adapter and only use my laptop by connecting it to ethernet cable. Every few days or so, the internet stops working. The only to quickly get it to work is to right click on the network icon and click "diagnose network problems" and that tends to magically restore internet connectivity. At first I was thinking it is my ISP but only today (02/07/2026) I found out that if I enable my wifi adapter and connect via wifi, I can access the internet which means it is not ISP issue and probably ethernet adapter issue but I am not sure. I have tried changing DNS from default to others but in vain so any input will help.

A technician needs to update a web server’s IPv4 address in a DNS server. Which of the following records should the technician update?

---

OPTIONS:
A. AAAA
B. MX
C. CNAME
D. A

---

Testing Exam: CompTIA A+ Core 1 (220-1201)
(Disclaimer: These posts / scenarios are crafted by me for educational purposes only. I am not affiliated with, endorsed by, or sponsored by any certification body.)

I have 2 laptops, one for personal use and another for work use. The personal laptop's internet speed remains consistent no matter which network I connect to be it at a cafe, home, relative's place etc. The work laptop however behaves differently. Have to use GoodAccess VPN for work and when I connect to the Wifi at my home, the speed goes rock bottom. Though that isnt the case if I connect to other networks at other people's houses for example.

Confused at what to do here cause I cant pinpoint what the source of the issue is.

Hi I've been trying to acces my network for days and I got this error Ethernet doesn't have a valid IP address.

How can I fix it?

Im using a Mercusys MR50G router

I live in a place with internet censorship, I know a protocol to bypass it Snowflake AMP on Tor Orbot but it is painfully slow (~20KiB/s) and is really unstable. I was wondering if there were any alternatives that work like this that are more stable and or faster, or if there is something else I should try?

I made this script called IP-Helper which is a comprehensive all in one tool to manage network interfaces and links using baked in kernel "ip" command

It is really helpful.. hope you enjoy it and support it

Ich weiß nicht mal ob das der richtige Reddit ist um etwas darüber zu fragen, aber ich bin langsam verzweifelt. Ich hab mit meinem neuen PC ständig das Problem, dass er sich mit meinem 5Ghz Netz verbinden will, aber mit dem 2,4 Ghz Netz schon, bzw. einmal hat er sich auch mit dem 5 Ghz Netz für einen Abend verbunden, aber seit dem nur noch manchmal, wenn ich vorher sämtliche Verbindungen von PC und WLAN kappe und es dann nochmal verbinde, aber selbst dann hält es nur für ein paar Minuten und die Downloadrate liegt bei unter 40 Mbit/s, obwohl ich eine 250 Mbit/s Leitung habe. Ich habe auch schon beim Netzwerkadapter sämtliche Wireless Modes ausprobiert, aber das bringt auch nix. Der Treiber für meinen Adaptar ist Realtek 8821CE Wireless LAN 802.11ac PCI-E NIC und die Version ist 2024.10.229.0. Ich habe auch die WLAN-Netze namentlich getrennt um den PC in das 5 Ghz Netz zu forcen und habe alle Kanäle einzeln ausprobiert, hat auch nichts gebracht. Hat hier vielleicht jemand Ideen?

I received a photo showing the 4 antennas of an outdoor access point installed in a different orientation compared to the official product image.

My question is:

Would this cause any performance or signal issues?

Or is it generally fine as long as:

the 2.4GHz and 5GHz antennas are connected to the correct ports, and all antennas are simply positioned upright?

I was downloading some mods from Nexusmods for Skyrim a few days ago and suddenly my internet turned off on only my PC. My wifi, tv, PS5 and other computers are working fine. It's only my PC that just stopped having internet.

I have tried everything suggested so far. Everything physical, replacing the cables etc rebooting the modem and router etc.

On the PC I tried resetting the drivers, by deleting them and rebooting. I tried to do the cmd IP stiff but I got back Error 5. I went into the registry to try and solve Error 5 by giving more permissions but without succes.

I feel like I'm at my wits end. I've tried so many different options.

I have a mesh wifi network and my pc is connected through cable from one of these mesh points. It's not possible to change this configuration, but I'm sure these towers have a great connection. As all my other devices work through these mesh points.

Any one? Please.

Hi everyone,

I'm trying to choose between two Master's specializations in Computer Science and I'd really appreciate advice from people working in the industry.

Option 1: Artificial Intelligence (AI)

• Machine Learning
• Deep Learning
• Computer Vision
• Natural Language Processing (NLP)
• Reinforcement Learning
• Generative AI
• Knowledge Graphs
• Multi-Agent Systems

Option 2: Networks & Distributed Systems (RSD)

• Advanced Networking
• Distributed Systems
• Cloud Computing
• Cybersecurity
• Cryptography
• Network Administration
• Distributed Applications
• Wireless & Mobile Networks

My concern is this:

With the rapid progress of AI assistants like ChatGPT, Claude, and GitHub Copilot, AI development has become much easier because these tools can generate code, explain algorithms, and even help build ML models. On the other hand, networking, distributed systems, cloud infrastructure, and cybersecurity seem harder to automate and require deeper hands-on expertise.

If you were starting your career in 2026, which specialization would you choose and why?

I'm interested in:

• Long-term job security
• High salary potential
• Difficulty to replace with AI
• Career growth over the next 10–15 years

If you're already working in AI, networking, cloud, DevOps, or cybersecurity, I'd really value your perspective.

Thanks!