Anti-Spam Recommendations for SMTP MTAs (RFC2505)
Original Publication Date: 1999-Feb-01
Included in the Prior Art Database: 2019-Feb-11
Internet Society Requests For Comment (RFCs)
This memo gives a number of implementation recommendations for SMTP, MTAs (Mail Transfer Agents, e.g. sendmail,) to make them more capable of reducing the impact of spam. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements.
Network Working Group G. Lindberg Request for Comments: 2505 Chalmers University of Technology BCP: 30 February 1999 Category: Best Current Practice
Anti-Spam Recommendations for SMTP MTAs
Status of this Memo
This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements. Distribution of this memo is unlimited.
Copyright (C) The Internet Society (1999). All Rights Reserved.
This memo gives a number of implementation recommendations for SMTP, , MTAs (Mail Transfer Agents, e.g. sendmail, ) to make them more capable of reducing the impact of spam(*).
The intent is that these recommendations will help clean up the spam situation, if applied on enough SMTP MTAs on the Internet, and that they should be used as guidelines for the various MTA vendors. We are fully aware that this is not the final solution, but if these recommendations were included, and used, on all Internet SMTP MTAs, things would improve considerably and give time to design a more long term solution. The Future Work section suggests some ideas that may be part of such a long term solution. It might, though, very well be the case that the ultimate solution is social, political, or legal, rather than technical in nature.
The implementor should be aware of the increased risk of denial of service attacks that several of the proposed methods might lead to. For example, increased number of queries to DNS servers and increased size of logfiles might both lead to overloaded systems and system crashes during an attack.
A brief summary of this memo is:
o Stop unauthorized mail relaying. o Spammers then have to operate in the open; deal with them. o Design a mail system that can handle spam.
Lindberg Best Current Practice [Page 1]
RFC 2505 Anti-Spam Recommendations February 1999
This memo is a Best Current Practice (BCP) RFC. As such it should be used as a guideline for SMTP MTA implementors to make their products more capable of preventing/handling spam. Despite this being its primary goal, an intended side effect is to suggest to the sysadmin/Postmaster community which "anti spam knobs" an SMTP MTA is expected to have.
However, this memo is not generally intended as a description on how to operate an SMTP MTA - which "knobs" to turn and how to configure the options. If suggestions are provided, they will be clearly marked and they should be read as such.
Mass unsolicited electronic mail, often known as spam(*), has increased considerably during a short period of time and has become a serious threat to the Internet email community as a whole. Something needs to be done fairly quickly.
The problem has several components:
o It is high volume, i.e. people get a lot of such mail in their mailboxes.
o It is completely "blind", i.e. there is no correlation between the receivers’ areas of interest and the actual mail sent out (at least if one assumes that...