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Open Relay-Anti-Spam

General Information

  1. What is Spam?
  2. Why is Span bad?
  3. What is an (Open) Relay?
  4. Why is an (Open) Relay bad?

Common Questions

  1. How do I send email from home?
  2. The email I send from my providers SMTP server doesn't have "@umd.umich.edu" after it. Why not?
  3. How can I make it say "@umd.umich.edu" again?
  4. If I still have problems, who can I talk with to resolve it?

What is Spam?
Spam is when the Internet is flooded with many copies of the same message, in an attempt to force the message on people who would not otherwise choose to receive it. Most spam is commercial advertising, often for dubious products, get-rich-quick schemes, or quasi-legal services. Spam costs the sender very little to send -- most of the costs are paid for by the recipient or the carriers rather than by the sender.

Why is Spam Bad?
Spam is the electronic version of junk mail we receive in our mailbox. Most, if not all spam is some sort of advertisement or special promotion by a vendor trying to get the word out on their gimmick. This type of email clogs up resources that would otherwise be used for normal email activities. Spammers know that people don't want to hear from them, and generally put fake return addresses on their messages so that they don't have to bear the cost of receiving responses from people to whom they've send messages. It also makes it hard on the users if the majority of the mail they receive is all junk.

What is an (Open) Relay?
An open relay is a mail server that allows anybody to utilize its features to send a piece of email from one party to another. A better way to look at it is to use the analogy of the post office. The post office doesn't care where the mail came from, it only knows it has to deliver it. Normally, this sounds OK, but if you take a look at the spam section above, you will see that it also allows spammers to utilize the mail server as the deliverer, thus spreading the spam to more people. Also, the return addresses are forged (the From: field) thus it makes it harder to tell where the mail came from.

A relay is also called an SMTP (Simple Mail Transfer Protocol) server. This allows your email program to send messages from your computer through the server, and then the server sends the message to the proper destination. You are REQUIRED to have some sort of SMTP service somewhere for you to be able to send a piece of email, otherwise, you could not send mail!

Why is an (Open) Relay Bad?
The biggest reason obviously is that spammers could potentially use the Open Relay SMTP server to send their junk email. This may not sound like much, but if your server is hit by massive amounts of spam, it can use up resources that would otherwise be used for normal operations. This usage can impact delivery speed, bandwidth, disk space, server processing, and many other facilities. It makes it that much harder for legitimate users to utilize the services.

Another big push recently in the email community is to crack down as much as possible on Open Relay systems. Several different web sites have been set up to list potential open relay as well as known spammer sites in an attempt to get them shut down. If you happen to run an open relay system, you could potentially be blocked from sending a message to a site that checks to see if you are on these lists. Thus, this creates a denial of service for users of the Open Relay.

How do I send email from home?
If you currently are on a campus computer, or you use mich.net (Merit) as your dialup provider, this does NOT affect you.

This will affect you if you currently utilize an email client installed on your pc at home AND if you do not use Merit as your dialup provider. In other words, if you utilize mercury.its.umd.umich.edu, mail.umd.umich.edu, pop.umd.umich.edu, or imap.umd.umich.edu as your SMTP server entry (the server that you send mail to, not the one you get mail from) this will affect you.

Use your ISP's mail server as your outgoing mail server. In Netscape, go to Preferences -> Mail & Newsgroups -> Mail Servers -> Outgoing Mail (SMTP) Server, and enter your ISP's mail server (see the picture below). Contact your Internet Service Provider (the people that provide your Internet connection) to find out the name of the email server they provide for you to send your email. Most ISPs have a service such as SMTP that you can utilize. Typically, the ISP's website provides help pages, or sometimes the documentation you initially received provides detailed instructions on the server hostnames you can use.

The mail I send from my provider's SMTP server doesn't say "@umd.umich.edu" anymore. Why not?
Without being too technical, the simplest explanation is that the server you send email through determines the hostname (the part after the <tt>@</tt>) of the email sent. If, for instance, you are using Ameritech as your provider, then your email, in all likelihood would be something like: "<username>@ameritech.net". If you want your email to still say <username>@umd.umich.edu, read the next question.

How can I get my mail to say "@umd.umich.edu" again?
This answer depends on what email client you are utilizing. In Netscape, go to Preferences -> Mail & Newsgroups -> Identity -> Reply-to Address. Enter your UM-D email address (i.e., uniqname@umd.umich.edu).

If I still have problems, who can I talk talk with to resolve it?
If you have any questions regarding this, you can phone or email the ITS Help Desk.