Top posts
Every blog post that took off on Hacker News, ranked by the votes of its best submission. 136 posts.
A visual guide to SSH tunnels
This page explains use cases and examples of SSH tunnels while visually presenting the traffic flows. For example, here's a reverse tunnel that allows only users from IP address 1.2.3.4 access to port 80 on the SSH client through an SSH server.
Mess with DNS
New tool: Mess with DNS!
Observing my cellphone switch towers
One of my favorite books is 2013 "High Performance Browser Networking" by Ilya Grigorik. Besides a wealth of actionable advice, the book is illustrated with captivating real life stories.
Running your own email is increasingly an artisanal choice, not a practical one
You're probably reading this page because you've attempted to access some part of my blog (Wandering Thoughts) or CSpace , the wiki thing it's part of. Unfortunately you're using a browser version that my anti-crawler precautions consider suspicious, most often because it's too old (most often this applies to versions…
Another free CA as an alternative to Let's Encrypt
As the use of HTTPS continues to increase across the Web, we need more support from Certificate Authorities that issue the certificates to make it all work. I'm a huge fan of Let's Encrypt and what they're doing, but if we want to encrypt the entire Web,
Sign arbitrary data with your SSH keys
ssh-keygen can sign and verify signatures, and it's way better than PGP
Hidden Networks in TP-Link Routers
I was debugging my WiFi settings this week when I noticed something strange. WiFi Analyzer was showing two hidden networks coming from my router, one for each frequency: 2.4GHz and 5GHz. Networks which I haven't configured and didn't appear in my router's admin interface. WTF?
5G: The outsourced elephant in the room
This article is part of a series on (European) innovation and capabilities. In a break from the usual GPS/Galileo, DNA and C++ posts, here is a bit on 5G and national security. It turns out that through PowerDNS and its parent company Open-Xchange, we know a lot about how large scale European communication service…
There oughta be a WiFi Game Boy cartridge
It took a while, but I finally managed to create my own Game Boy cartridge. With WiFi! At this point, it can only demo a simple telnet-style communication and access Wikipedia articles, but I am confident that I will showcase more in the future. For now, the interesting and surprisingly tricky part is how the thing…
Starlink review, four months in
SpaceX's Starlink internet service uses satellites in low-earth orbit to provide high-speed Internet to underserved parts of the world, especially places without easy access to cable or fiber. SpaceX's Starlink beta opened up in my area, so I installed Dishy—that's the nickname for the large white satellite dish…
25 Gigabit Linux internet router PC build
init7 recently announced that with their FTTH fiber offering Fiber7, they will now sell and connect you with 25 Gbit/s (Fiber7-X2) or 10 Gbit/s (Fiber7-X) fiber optics, if you want more than 1 Gbit/s. While this offer will only become available at my location late this year (or possibly later due to the supply chain…
Zero click vulnerability in Apple’s macOS Mail
Zero-Click Zip TL;DR
Let's code a TCP/IP stack (2016)
Writing your own TCP/IP stack may seem like a daunting task. Indeed, TCP has accumulated many specifications over its lifetime of more than thirty years. The core specification, however, is seemingly compact[^tcp-roadmap] - the important parts being TCP header parsing, the state machine, congestion control and…
Running a fake power plant on the internet for a month
There is a lot more on the internet than just social media and banking websites…
Tor is a great sysadmin tool (2020)
Using Tor to aid various system administration tasks, including checking firewall rules, bypassing internal network restrictions and connecting to remote systems that are behind NAT/CGNAT.
MarkMonitor left 60k domains for the taking
Thanks to Nagli and d0xing for helping figure out what was happening with this issue.
ADSL works over wet string (2017)
Broadband services are a wonderful innovation of our time, using multiple frequency bands (hence the name) to carry signals over wires (us...
Bye CUPS: Printing with Netcat
Turns out printing doesn't have to be hard
Dear EU: Please Don't Ruin the Root
I love Europe, and I want to see the European Union succeed. I also love the Internet, and I want to see it thrive as well. And it therefore pains me that it now appears that the European Union might inadvertently be picking an ugly fight with “The Internet”. UPDATE: I am EXCEPTIONALLY happy to report that through…
Setting up Starlink
In March, I got an email from SpaceX saying Starlink was available at my address, and I could pre-order. I paid $500 for the equipment, plus $25 for a Volcano Roof Mount, and $99 for the first month of service, and a few weeks later, I got the kit you see in the image above. I was a little too excited about getting…
My ISP Is Killing My Idle SSH Sessions
tl;dr: My ISP’s CGNAT session timeout is too short, meaning TCP keepalives gets dropped. Test if your own NAT, or your ISP’s CGN, violates RFC5382 ‘s REQ-5 using this tool: https://github.com/AndersTrier/NAT-TCP-test .
There are six internet links on my office on wheels—seven when Starlink arrives
If you are going to work remotely anywhere in Australia from a van, you need damn good internet. Here's how I put together a vehicle with the best internet connectivity in Australia.