Gmail Filters

I have been using Gmail a lot lately. The reason I am steadily increasing the use of the service flows mainly from a unique feature of Gmail: filters.

Gmail filters can be used in many ways. I’m using them to identify the source of email messages that are sent to me. Whenever I register online when I purchase something or I want to use an online service, I use my Gmail email address when completing the registration form. When I enter the address I add an identifier. Then, whenever I get an email message using that identifier, I know where the sender got the email address.

So, let me give an example. I recently rented a car using Priceline dot com. When I registered at the site, I used "jkdmail+priceline@gmail" dot com for the email address. The "+priceline" is the identifier. Then I went to my Gmail account and added a filter I called “Priceline.” This filter captures every email message coming into my inbox that has the +priceline identifier. I can view new and archived messages using the filter.

This works great, but I have run into an occasional problem. Every once in a while I register at a website that will not allow the identifier in the email address. For many months this has not been a big deal, I would just email the company and asked them to change their validation criteria so Gmail, with an identifier added, would be accepted. Everyone was glad to do so. The new Glide dot com website is an example of a site where I got this kind of quick response.

There are companies that will not change their email validation criteria. One such company is DHD Media, a company that provides website registration services, credit card processing and billing, streaming media and DRM, and managed hosting for a number of companies. When they refused to change their email address validation criteria, I sent them this message:

This feature of Gmail is the principal reason I use the Gmail service. Gmail has this feature to allow accountholders to filter email. I use it to identify the source of the messages I receive. If I get spam that uses the identifier, I know where the spammer got my email address.

It takes effort on the part of Web form designer to rule out the "+" sign in an email address. I assume there is purpose behind this effort. The only purpose I can think of is that they do not want me to identify email sent from the site or from the people to whom they sold the information.

Please let me know if you change your policy to allow Gmail with the filter identifier. I'll subscribe to your service then.

They would not budge. I told them that I was going to post an article on this blog about the Gmail filter feature and would include the fact that they refused to edit their email address validation criteria. I offered to include a statement from them concerning the matter. Here is what they had to say (this is a copy of the message, including grammar and spelling errors):

DHD Media does not sell e-mail address, nor could we even benefit from such an action since we are a billing processor as opposed to an e-business.

The resons are much less complex.  The plus sign is an operator in most programming languages.  All operator charcaters are disabled in order to prevent security breaches.  DHD handles too much sensitive account information to present such risks.

It is unusual to me that many websites would change their e-mail criteria for a mail service that google clearly states is *still* in its testing phase in spite of its popularity.  This is something to keep in mind when considering gmail's features.

Regards,
William
Tech Support
DHD Media

I have asked a number of friends about this and they all got a chuckle out of William’s “resons.” No one can think of any situation where a plus sign in an email address would effect any program written in any language, much less create a security breach.

So, the bottom line is that I did not pay over $100 for the service offered through DHD Media. Gmail made it possible for me to know before registering at the site that my credit card and other sensitive information might be used for God knows what.

Thank you, Google.

Comments

[Rusty]

The + thing isn't only a gmail feature. Most MTA's support it including sendmail, postfix, etc...

I wouldn't be surprised if a malicious spammer did a simple s/\+.*// to remove any use of it.

Even still the feature is undeniably useful.