DNS is one of the Internet’s most fundamental services, yet it’s often reduced to “it converts domain names into IP addresses.” In reality, there’s much more happening behind every DNS lookup.
I wrote an extensive guide that starts with the fundamentals and progressively moves into modern DNS architecture, security, and administration. It covers the complete DNS resolution process, recursive and authoritative servers, resource records, packet-level analysis, DNSSEC, encrypted DNS (DoH, DoT, and DoQ), common attack techniques such as cache poisoning, tunneling, rebinding, and amplification attacks, as well as deploying and securing a production-ready BIND 9 DNS server.
The goal was to explain not only how DNS works, but also why it was designed this way and how it is operated and secured in modern networks.
Every device on a local network needs a way to translate an IP address into a physical MAC address before communication can begin. That’s the job of ARP (Address Resolution Protocol). This guide breaks down the complete ARP workflow, including requests, replies, ARP caching, Gratuitous ARP, Proxy ARP, packet captures, common troubleshooting techniques, and security issues such as ARP spoofing. Whether you’re studying networking fundamentals, preparing for CCNA, or just want to understand what happens behind the scenes on a LAN, this article has you covered.
Networking is one of those topics that feels complicated until someone explains the fundamentals clearly. This guide covers the core concepts behind modern computer networks, including IP addressing, MAC addresses, TCP/IP, the OSI model, DNS, DHCP, NAT, routing, switching, ports, and common protocols
Bluetooth is one of the most widely deployed wireless technologies, yet most discussions barely scratch the surface of how it actually works. Underneath the simple “Pair” button is a layered networking stack that includes HCI, L2CAP, SDP, RFCOMM, ATT, GATT, SMP, and several application profiles, all working together to establish secure communication between devices. Like any complex networking protocol, Bluetooth has also had its share of implementation flaws, from early attacks like Bluesnarfing and Bluebugging to more recent vulnerabilities such as BlueBorne, KNOB, BIAS, BLESA, and SweynTooth. Here’s a comprehensive guide to everything about Bluetooth
i have a ton of all russian subnets which i doesnt want route through vpn due vpn monitoring on rzzian faschist services, and services which blocking all non-rzzian ips
A part of 6Ghz spectrum was recently (approx 4-5 months ago) was delicensed for WiFi usage in my country. Intel pushed an update soon after that to enable the 6Ghz band. Even my router manufacturer..TPLink did the same and my S26U updated to unlock 6Ghz and even on One UI 9 there is option for 6Ghz hotspot. The issue is, my router’s 6Ghz Band can bee seen by my phone and it can connect to it too without any problem. But, my laptop is unable to see any 6Ghz network.. neither my TPLink router nor my phone’s hotspot. Latest updates applied to every device. Any idea how to fix it?
Looking for feedback on Wireguard capable wifi routers that keep a persistent link from the router to an endpoint. A lot of what I see advertised as “Wireguard Supported” sets up a server and not a client.
We’re currently implementing additional security controls for our hosting platform, and one of the biggest challenges we’re encountering involves customers connecting over mobile networks. As users move between towers or regions they are frequently assigned different IP addresses within very short timeframes, which complicates IP-based allow-listing.
Edit for anyone that finds this later: my problem was that I was missing a route in the VMs to send traffic for the OpenVPN subnet to the main host bridge interface. So, it was using “default”, which sent it to my internet router.
After connecting to my new ISP (Deutsche Glasfaser) successfully via IPv4 (systemd-networkd got a CGNATt’ed address like expected), I noticed that I had no IPv6 address. I then spent days on researching PPPoE, 6rd and what parameters/prefixes/relays my ISP may use, as neither systemd-networkd, NetworkManager nor dhcpcd were even able to find a DHCPv6 server, neither in unconfigured nor configured (routable IPv4) state.
Scanning with nmap (sudo nmap (-6) –script broadcast-dhcp(6)-discover) didn’t find anything either.
So I have a very specific use case and need to use my old backup win10 laptop for a test (only windows or mac allowed, no linux). I never connect this laptop to the internet because I need it to stay on 10 to work with specific software/hardware I have on it. But this test requires internet. How can I block the windows update servers on my VLAN? I know the second I connect this thing microslop will corrupt it to force me to update.
By the skin of my teeth. 72 questions.
I blasted through the last questions. Time closed on question 72.
The lablet section must have had a lot of point value. I spent an hour on them, got em right. Got all the subnetting shit. Think I nailed IPv6.
I decided to get my CCNA last summer after losing out on a senior role because I didn’t have it. I signed up for the free CCST training and completed Network and Cybersecurity, tested in January.
I unfortunately HAD to get a stupid thermostat with wifi. can’t even get one without it now. I’d much rather have it not hooked up but I may be forced to.
I just finished my Cisco CCST Cybersecurity. The whole course of study is pretty much to get you skilled up enough to operate and understand the Security Onion console. The last half of the last class is all about handling the alerts.
Allow affiliate & tracking domains common on deals websites, in emails or in search results. Those usually only get called after manually clicking on a link.
Bypass Age Verification Auto bypass age verification checks used by certain websites, such as adult content sites, to verify a visitor’s age before allowing access. By enabling this feature, you acknowledge that you are legally old enough to access the content.
I’ve always wondered whether network interfaces that have these flashing lights flash as a gimmick or do they actually indicate the flow of traffic? Perhaps one flash per packet in or out? I wish I could remember what my call up modem looked like to make a historical comparison too.
In the early 1990s, internetworking wonks realized the world was not many years away from running out of Internet Protocol version 4 (IPv4) addresses, the numbers needed to identify any device connected to the public internet. Noting booming interest in the internet, the internet community went looking for ways to avoid an IP address shortage that many feared would harm technology adoption and therefore the global economy.
Why would I need to have software firewalls on my devices behind my NAT router at home? The topology is a basic consumer grade one: ISP -> my router (NAT) -> LAN, and vice versa.
EDIT: Got an email from my ISP saying “the fiber owner has resolved your issue, we are closing the ticket.” I immediately called my ISP out of curiosity, since they earlier had told me that they need to change my ONT for me to get my full speed. Well, it turns out, the fiber owner (don’t know the English word for them) can manage speed per port on the ONT. Sic. So for some reason, they had limited the speed to 100 Mbps.
I’ve had Frontier fiber internet for the past 2-ish years. No complaints at all, but the nerd in me desires IPv6. I have the Frontier provided ONT device but declined their router. I have a MikroTik RB5009 which has been “searching” for an IPv6 prefix.
I have been looking into setting up a secure home/small business server and hardening my local network and I came across this kickstarter which is currently floundering, likely because it’s campaign page is way too technical without enough fluff for the uninformed out there (like myself to some extent). For reference I work in small industry and have some interest in implementing more IOT.
We have a wireless camera connected to our wifi, but the concrete wall makes the signal inconsistent. There is an available POE port nearby indoors, and the existing wifi which has a good signal indoors.
Hello everyone!
Managed to get my hands on a HPE V1910 JE007a switch I’m planning to use on my home lab.
Does anyone know if there’s a FOSS firmware that can be used on it?
I’m a homelabber but know next to nothing about IPv6. What I do know, however, is that my ISP, Bell Canada, doesn’t support it. If Bell were to work toward IPv6 support what actually needs to be done?
Here’s a question that I can’t seem to find more info on the internet on, so I’m turning to Lemmy. Does anyone have a better understanding of the specifications around an ONT. I know it basically converts the incoming fiber (usually single mode single fiber) to an RJ45 jack for copper runs but that’s the part I’m curious about:
Hi,
Anyone doing audit’s on their routers & switches? If so, what are you using for that? For starters I’m just after the simple things like old management addresses being absent, certain firmware versions not being used, some accounts which are or are not there etc.
(I’ve been thinking something like grep on oxidized backups but there sure must be a better way of doing it)
My Netgear Nighthawk wifi router just crapped out last weekend and I’m gimping along on the rental wifi router from my ISP, so I’m looking to buy a replacement and am torn: should I go with a single WiFi Router or a wired router plus a wireless access point?
I’ve been a proud owner of a Ubiquiti Dream Router for a good while now - live in a rural area so the Dream Machine would’ve been overkill for my needs.
Has anybody heard if the upcoming 47-day maximum on TLS cert lifetime will apply to Enterprise wifi auth using private PKI (especally on IOS and Android)?
Background:
I have a cellular ISP and therefore cannot configure the CGNAT. After burning through some dumb ideas (free reverse proxy, docker) I realized I could just use my paid VPN.
What if we could reinvent networking from the ground up—no collisions, no IPv4 exhaustion, no centralized configuration—just a clean, scalable, self-managing system? Introducing Orbula: a fresh protocol built on logical-ring/physical-star topology using standard CAT6 cabling.
I will be moving into a new house in a few weeks. It’s an older house (built in the 60s) and hasn’t had much updates in terms of wiring. I want to be able to run a hardwire cable to each bedroom to maximize my Internet performance. My wife works from home and I’m hybrid, so I want to ensure we’re not just flying on WiFi.
I have an off-grid setup with a few devices on a local network that is not connected to the internet. I can tell my iPhone to use the non-internet wireless LAN to talk to those devices, OR I can tell it to use cellular data to talk to the Internet, but there’s no config on the iPhone side to let them be both live at the same time.
Would it be unwise to make my file server (SSH only) machine (also runs a Minecraft server, And From time to time runs RSTS/E under simh) a tailscale router node to allow my traveling notebood access to the network when I am away?
I’m looking to automate/script my pfsense wireguard tunnels so that each wireguard tunnel only goes up if there are one or more clients connected to the subnet associated with that tunnel and goes down once all clients have disconnected. I was wondering if there is already a plugin that accomplishes this or can be adapted, otherwise what is best practice for running scripts on the pfsense box?
I’m self studying for a server+ cert and ran into this paragraph. Am I right that CPU time is a set of ticks utilized, the CPU Capacity is the total capacity, and the CPU usage is the percentage of ticks:capacity?
Nord.pub
Juniperus
Lucy :3
dbtng
durinn
walden
ExtremeDullard
Possibly linux
Cooper8
Cyanogenmon
ThorrJo
Donatello
early_riser
𝚝𝚛𝚔
UntouchedWagons
redlemace
anticonnor
