E-mail Aliases

2010, Mar 02    

For a while, I’ve been creating an email alias for every site that I have to create an account for.

For example, let’s say that my email address is example@vertigion.com. When I went to DreamHost.com and made an account for them, I would create an alias such as:

example.dreamhost.com@vertigion.com > example@vertigion.com

Email that was sent to example.dreamhost.com@vertigion.com would show up in my example@vertigion.com inbox.

Why? If DreamHost.com ever sells my email, I know exactly who is selling my email address. When they do sell it, I can redirect all mail to that address to my junk account instead of blocking each spammer as my email is resold. Basically, I could set a rule to block the To address instead of every new From address.

Anyway, it was easy enough to do for me cause I know how to do it, but then I told some of my family about how I prevent spam mail and they got excited and wanted to do it too. Of course, I wasn’t comfortable giving them admin access to my server so they could alias their email addresses, so I did some digging in the interwebs and found some interesting information referencing sub-addressing.

Wow! Now, I don’t even have to log into the server to alias my address for each website! It’s like auto-aliasing:
example+dreamhost.com@vertigion.com > example@vertigion.com

How do I know if my email server supports sub-addressing? Try it!! Example+test@vertigion.com would be a good test. Apparently, some sub-addressing support hyphens as well, so you might want to try example-test@vertigion.com. If either (or both) show up in your inbox, you’ll know it works! How cool is that?

The best part is, I don’t have to subject my email server to people who don’t really know what they are doing.

Any downsides?

  • Well … it is a supported/used syntax, so it’s possible that a hacker/email-seller/email-buyer could filter the plus (+) syntax off and just send the email to example@vertigion.com. I guess at that point you’re no worse off than before …
  • “Some mail servers violate RFC 5322, and the recommendations in RFC 3696, by refusing to send mail addressed to a user on another system merely because the local-part of the address contains the plus sign (+)” (Ref: Wikipedia). This has a few implications:
  • Some mail servers will not send to your address with the plus (+) sign despite thespecifications.
  • Some web sites may consider the plus (+) sign to be invalid despite the specifications.


For those using Vertigion.com email …
We support the plus (+) syntax, and will continue to support the plus (+) syntax after our email migration.