DKIM and Mailing Lists

The Problem

DKIM is a standard for digitally signing mail to prove it’s authenticity and prove that it was not modified. In an ideal situation it can be used to reject corrupted or forged messages.

DMARC and ADSP are standards for indicating that mail from a domain should be signed. This prevents hostile parties from […]

How to Debug POP

POP (Post Office Protocol) is the most used protocol for receiving mail from a server to a MUA (Mail User Agent) for reading. It is specified in RFC1939.

But the way it works (in most cases) is quite simple and doesn’t require reading the RFC, connect to port 110 (the standard port for POP3) and […]

How to Debug SMTP with TLS(SSL) and AUTH

The first thing to test is a TLS (aka SSL) connection. The stunnel program has special code for this, the command “stunnel -n smtp -c -r” will connect to the server via SMTP and negotiate SSL.

If you use gnutls then the command “gnutls-cli -s -p 25” will connect to the server, allow […]

Running the Net After a Collapse

I’ve been thinking about what we need in Australia to preserve the free software community in the face of an economic collapse (let’s not pretend that the US can collapse without taking Australia down too). For current practices of using the Internet and developing free software to continue it seems that we need the following […]

Personal SEO

One problem many people encounter is the fact that they don’t appear on Google and other search engines the way that they like. If you have an uncommon name which is not referenced in any popular web pages then a single mention in a popular site can immediately become the top hit, this may not […]

How to Report an Email Problem

In my work I often receive problem reports from clients regarding their email service, here is some advice to help get the problem fixed as fast as possible:

Firstly problems sending mail and problems receiving mail are often unconnected and should be reported separately. If only one aspect of a problem is reported then probably […]

Unique Names

Prior to wide-spread use of the Internet it was reasonable to expect that if you had a family name that was not really common and a given name that was also not really common then you might never meet someone else with the same combination of first and last names as yourself. I have never […]