1 - Everyone
2 - Intermediate
3 - Advanced
Tips & Tricks
- A basic introduction to encryption (1)
- When you want to communicate in secret, you whisper in someone's ear. When you need to do the same thing across a crowded room, you use a secret language (that only the two of you know). How do you do the same with someone you've never met? This tip starts at the basics and shows you how different types of encryption work ("from the ground up"). Clear and concise examples illustrate current techniques for private key encryption, secret key exchange and public key cryptography.
- Troubleshooting SSL communications using network dumps (3)
- While the actual communication over SSL is encrypted and can't be viewed without the server's private key (and client's private key if doing mutual authentication), you can still do some fairly complete troubleshooting using only a network trace tool (such as 'tcpdump' or 'snoop').
- How to protect your email address on web pages (1)
- Unfortunately, junk email (spam) accounts for about 85% of all email sent today. Every time you place your email address on a web page for people to see, it is also available to "spam spiders" (automated programs designed to harvest email addresses from web pages). The issue is "How do you make your email address available to real human beings while hiding it from nasty programs?" While there are several techniques to do this, they often require the human user to do something extra. What we really want is a way to do this without inconveniencing the human. This tip shows you how to do that.
- Authenticate your outgoing email - How to setup SPF records (2)
- If you own your own domain name, you can reduce the amount of "backscatter" (false bounces) you get. You can also help prevent the abuse of your email addresses in spam messages (which appear to have come from you). In addition, this may help you recover from a "bad reputation" if your domain name has already been associated with spam. While identifying incoming spam is an ongoing problem, it's very easy to tell the world that only servers you specify can send email from your domain name.