Email is still the most common communication protocol on the Internet. And since I was missing some variants of the related protocols, IMAP, POP3, and SMTP in the Ultimate PCAP, I did some captures. ✅ Here are a few details.
Tag Archives: SMTPS
IPv6 Upper Layer Protocol Samples
Some time ago I published a pcap that can be used to study basic IPv6 protocol messages such as ICMPv6 for Router Advertisements, Neighbor Solicitations, etc.: “Basic IPv6 Messages: Wireshark Capture“. You can use it to learn the basic IPv6 address assignment and layer 2 address resolution. However, that pcap does not include any upper layer protocols.
This time I captured a few application layer protocols that I used over IPv6 rather than over legacy IP. Common user protocols such as DNS, HTTP/S, IMAP, SMTP (with STARTTLS), as well as some network administration protocols: SSH, SNMP, and Ping. It is not that interesting at all ;) though you can use it to have some examples for Wireshark to prove that those application protocols are almost the same when run above IPv6 compared to IPv4.
In Sync 2017
It is not easy to sync the own files/mails/contacts/calendars/etc. in order to keep them private (not via a public cloud) and to create regular backups. Furthermore, every solution must be easy to use (at least for my wife ;)) and reliable.
Following is my approach for keeping my files in sync and private. What are yours?
How to use DANE/TLSA
DNS-based Authentication of Named Entities (DANE) is a great feature that uses the advantages of a DNSSEC signed zone in order to tell the client which TLS certificate he has to expect when connecting to a secure destination over HTTPS or SMTPS. Via a secure channel (DNSSEC) the client can request the public key of the server. This means, that a Man-in-the-Middle attack (MITM) with a spoofed certificate would be exposed directly, i.e., is not possible anymore. Furthermore, the trust to certificate authorities (CAs) is not needed anymore.
In this blog post, I will show how to use DANE and its DNS records within an authoritative DNS server to provide enhanced security features for the public.
E-Mail Übertragung verschlüsseln
Zur Zeit wird viel über Abhörmaßnahmen im Internet und speziell über das generelle Mitschneiden von Traffic normaler User geredet. Und während große Firmen gezielt Verschlüsselungstechniken einsetzen können hat der Otto Normalverbraucher kaum das Wissen, um ernsthaft etwas gegen das Mitschneiden seiner Daten zu tun. Dabei ist es gar nicht so schwer, zumindest die Übertragung der eigenen E-Mails hin zu seinem Provider über entsprechende Maßnahmen abzusichern. Ob man damit die internationalen Geheimdienste aussperrt bleibt fraglich, aber zumindest schränkt man das Mitlesen der privaten E-Mails durch Unbefugte im Internet deutlich ein! Hier kommt also eine Erklärung inkl. einiger Screenshots der gängigen E-Mail Programme und Smartphones, um die eigenen E-Mails über einen verschlüsselten Kanal zu übertragen. Continue reading E-Mail Übertragung verschlüsseln