General information security topics | Home network | DNS | Identity management | Instant messaging | Operating systems | Repositories | Secure key and password storage

This page contains security-related recommendations. Kindly note that we exclusively recommend hardware, software and services which we actually use and own. We do not recommend any products based on sponsoring or things we only know from hearsay.

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  • [BOO] books
  • [HW] hardware
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General information security topics

Other interesting projects from the InfoSec world.

Home network

Your home network connects you and your family to the internet. The most vulnerable point is your router since it has to fulfill different functions and is the primary point of entry for a remote attacker. Feel free to read our home network security series.


Many private users are totally focused on HTTPS, and forget about their insecure DNS traffic. Cleartext DNS traffic can be modified or logged, and third parties can learn about your surfing habits. People who are familiar with network protocols and DNS can configure DNSSEC as well as DNS-over-TLS. If configured correctly, you get validated DNS responses, and your DNS traffic is authenticated and encrypted.

Identity management

Identity theft is a main threat to individuals on the internet. The best way to defend your personal data online is to stop using online services at all. This is quite unrealistic. Another way is to use services which provide cryptographic proof so others can verify that you actually own certain online accounts.

Instant messaging

Ask 10 people about their preferred instant messenger and you’ll get 15 recommendations. Some people say that federation is best for privacy (no), some recommend closed-source messengers like Threema and most people keep on using WhatsApp. We aren’t interested in wars of opinions and stay with the facts.


Security warning: We urgently recommend running your own XMPP server, or using a server that is run by a close friend/family member. XMPP server admins can access and manipulate all of your data including contacts, groups, password etc. Furthermore, they can inject messages with spoofed sender IDs. Server-side parties can do this even if you enable OMEMO encryption and use XMPP only via Tor. This is neither "secure messaging" nor privacy-friendly.

Usability note: Well-known XMPP clients implement XMPP itself, however, they do not implement each and every XEP. This means that you have to carefully evaluate which XEPs you want to use and whether your client supports them. Especially "XEP-0384: OMEMO Encryption" isn't widely or only partially (e.g. no OMEMO in MUCs) supported by clients.

Operating systems

We recommend the following operating systems for advanced users:


The following repositories contain useful resources and links:

Secure key and password storage

If you use GnuPG, SSH etc., you probably store your keys on your computer. This isn’t very secure and stolen keys can result in data breaches (SSH) and decrypted messages (GnuPG). Use dedicated security hardware to store your keys. Furthermore, use password management software like KeePass to store your passwords encrypted. Some products also support OATH-TOTP, U2F for 2FA, and/or WebAuthn.