DKIM

September 28, 2023 Leave a comment

DKIM. No, it’s not a new singer/rapper/influencer/whatever. It’s a DNS controlled Email Authentication mechanism. What does that mean? Well, if you want a technical explanation, go see my article on Authorization vs Authentication, since that is important to understand if you want to understand DKIM. DKIM stands for DomainKeys Identified Mail. It uses a feature of Public Key Authentication to allow receiving mail servers to verify that the message is not modified in transit and that the sender is authentic. …

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Resolving the Internal and External DNS zone Dilemma with Pinpoint DNS

April 24, 2017 Leave a comment

Here’s an interesting trick that might help you resolve some of your DNS management woes, particularly if you have a different Public and Private DNS zone in your environment. For instance, you have a domain name of whatever.com externally, but use whatever.local internally. When your DNS is set up like that, all attempts to access systems using the whatever.com…

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What is a DNS SRV record?

September 21, 2016 Leave a comment

If you’ve had to work with Active Directory or Exchange, there’s a good chance you’ve come across a feature of DNS called a SRV record. SRV records are an extremely important part of Active Directory (They are, in fact, the foundation of AD) and an optional part of Exchange Autodiscover. There are a lot of other applications that use SRV records to some degree or another (Lync/Skype for Business relies heavily on them, for instance).The…

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Anatomy of a Certificate Error

January 29, 2016 Leave a comment

The most important step in diagnosing a specific security error involves determining what the error is telling you. There are a few things that can cause certificate errors, and what you do depends entirely on what is causing the error to begin with. Once you know what the error is telling you, it becomes much easier to figure out what you need to do next.…

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