I was presenting at the annual “Wireshark Developer and User Conference“, the SharkFest’25 EU, talking about “Securing DNS – Attacks and Defences“. It covered all the buzzwords related to DNS security, such as malware using DNS, DNS spoofing, DNS exfiltration & tunnelling, while defending them with the keywords as DNSSEC, DoH/DoT, feeds & blocklists, and so on.
Quite many techniques. ;) Luckily, the whole session was recorded. So if you’re interested, have a look!
I did a presentation at SharkFest’24 EU in Vienna, the “Wireshark Developer and User Conference“, about the topic: “Unveiling Network Errors – A Deep Dive into ICMP ‘Destination Unreachable’ Messages“. It covers the following:
“Effective troubleshooting of network issues is a critical concern for network technicians. While many are familiar with basic ICMP tools like ping and traceroute, the breadth of ICMP capabilities often goes underutilised. This session delves into ICMP messages, specifically the ‘Destination Unreachable’ type, and the insights they provide into network errors.
We will explore methods for capturing and analysing network traffic, highlighting practical tips and tricks for using Wireshark to diagnose and resolve issues efficiently. Attendees will gain a deeper understanding of ICMP message functions and how to leverage them for improved network troubleshooting.”
You can watch the whole session and download the slides. And you can do the six challenges at the end of the session as well. (The answers are not in the PDF, but shown in the video.)
Continue reading ICMP ‘Destination Unreachable’ Messages @ SharkFest’24 EU
This time (2023) at the yearly Wireshark Developer and User Conference in Europe, I gave a talk about DNS. How could it have been any different –> The title simply had to be ‘It’s Always DNS‘. 😂
“This session dives deeper into the Domain Name System, covering recursive vs. iterative DNS queries, resource records types, TTL & caching, DNS errors, a little DNSSEC, flags, and of course: Wireshark with its useful display filters, custom columns, colouring rules, and so on. And we will explore some other tools to analyze and troubleshoot DNS even further.”
You can watch the whole session and download the slides. And you can do the six challenges at the end of the session as well. (The answers are not in the PDF, but shown in the video.)
For many years I was afraid to open new issues for open-source tools since I am not a coder at all and won’t ever be able to fix some of the problems. Many times I got answers like “The source is open, go ahead and fix it yourself”. This brought me to a point where I simply stopped proposing new ideas and features.
This has changed since I was at SharkFest’22 EUROPE (the Wireshark Developer and User Conference), especially at a session from Uli Heilmeier called “Contribute to Wireshark – the low hanging fruits” [PDF].
And that is exactly what I would like to recommend to you. This post is about giving examples, that even minor errors and thoughts are appreciated by the Wireshark team. But, of course, if you actually have coding skills, please go ahead and fix some of the issues. ;)
Continue reading Contributing to Wireshark (without any coding skills!)
Fortunately, there was a SharkFest – the “Wireshark Developer and User Conference” – this year in Europe again. I was there and gave an IPv6 Crash Course likewise. Yeah! It’s my favourite topic, you know. 75 minutes full of content, hence the name crash course.
Here are my slides as well as the video recording. If you want a crash course for IPv6, here we go:
I gave a session about IPv6 at SharkFest’19 EUROPE, the annual Wireshark developer and user community conference, named “IPv6 Crash Course: Understanding IPv6 as seen on the wire“. The talk is about the IPv6 basics, which are: IPv6 addresses & address assignment, link-layer address resolution, and ICMPv6. Tips for using Wireshark coloring rules and display filters round things up.
As I have not yet published the slides, here they are. Unfortunately, we were not able to record the session due to technical problems. Neither the video nor the audio. ;( Hence, here are only mere slides.
I did a session at SharkFest’18 Europe in Vienna with the title of “Crash Course: IPv6 and Network Protocols“. Since the presentation slides + audio were recorded you can listen to the talk, too. Here are some notes about the motivation for this session as well as feedback from the attendees.
Continue reading SharkFest’18 Europe: Crash Course: IPv6 and Network Protocols