Third-party mail relaying occurs when a UConn mail server allows an external user's (external to UConn) e-mail client to send mail to a UConn mail server for processing and delivery to a user who is not on that mail server. In such a case, the UConn mail server allows non-UConn individuals on the Internet to send e-mail through UConn to a non-UConn e-mail address. This is a misuse of UConn funded resources and can interfere with the legitimate work of UConn students and employees. Mail relaying is often used to send spam.
Spam is unsolicited mail sent to a number of e-mail addresses, usually to solicit business. It is not only annoying or offensive but can also be harmful to the e-mail system by flooding the mail queue of the mail server or of an individual user. By using a mail relay, a spammer tries to hide the true source of the spam. By spoofing (using a false or fake e-mail address), the spammer hides the true e-mail address from which the spam was sent.
A greater problem is mail relaying which results in UConn e-mail users being unable to communicate with certain Internet users. Mail servers at some organizations will not accept mail from any mail server which allows mail relaying. Lists such as the Open Relay Blocking System (ORBS) list and the Mail Abuse Protection System (MAPS) Realtime Blackhole List (RBL) identify servers which allow relaying.
Third party mail relaying most often occurs when a p.c. user tries to send mail to a mail server to be delivered to a recipient that is not on the same mail server. The user configures his or her e-mail address in the mail software (Netscape, Pegasus, etc.). The user enters his or her own e-mail address (the address of the server where the user has the account) and also chooses a mail server from which the p.c. will obtain outgoing mail (SMTP) service. The user should obtain outgoing mail (SMTP) service from the mail server on which the user has an account. If the user selects some other mail server, third party mail relaying will take place.
A mail server may only allow third party mail relaying if the message originates from a computer physically connected to the UConn network. UConn PPP service is physically connected to the UConn network. In other words, third party mail relaying may only be allowed from an I.P. address that is on the UConn network (i.e. part of the '.UConn.Edu' domain).
No mail server may allow third party mail relay for any I.P. address outside of the '.UConn.Edu' domain.
If any UConn mail server does not conform to this policy it will be prevented from sending mail to other mail servers on the UConn network that do conform to this policy. The result will be that users on the non-conforming mail server will be unable to communicate with users on other UConn mail servers.
Those who have a non-UConn Internet Service Provider (ISP) should use the ISP's mail server to send their outgoing mail. Attempts to use a UConn mail host from an external ISP will result in an error message and nondelivery of the outgoing mail. This situation applies only to those who currently use a non-UConn ISP and have configured their mail client to use a UConn mail server (e.g. uconnvm.uconn.edu) to obtain outgoing mail (SMTP) service for mail they wish to send to others at UConn or on the Internet.
The following is a list of outgoing mail (SMTP) servers for various ISP's:
UConn Health Center cortex.uchc.edu RCN (UConn.CTED.Net) mail.uconn.cted.net SNET smtp.snet.net Connix smtp.connix.com Neca neca.com Earthlink mail.earthlink.net Javanet mail.javanet.com IBM Net smtp1.ibm.net AT&T gateway1.worldnet.att.net
If you should have questions, please contact the Computer Center Help Desk at 486-4357/HELP.
Excellent sources of information on this problem are located at:
Mail Abuse Protection System Transport Security Initiative
Open Relay Blocking System (ORBS)
Definitions of Spam, Spamming, Spoofing, Mail Forwarding