Book Image

SpamAssassin: A practical guide to integration and configuration

Book Image

SpamAssassin: A practical guide to integration and configuration

Overview of this book

As a busy administrator, you know Spam is a major distraction in todays network. The effects range from inappropriate content arriving in the mailboxes up to contact email addresses placed on a website being deluged with unsolicited mail, causing valid enquiries and sales leads to be lost and wasting employee time. The perception of the problem of spam is as big as the reality. In response to the growing problem of spam, a number of free and commercial applications and services have been developed to help network administrators and email users combat spam. Its up to you to choose and then get the most out of an antispam solution. Free to use, flexible, and effective, SpamAssassin has become the most popular open source antispam application. Its unique combination of power and flexibility make it the right choice. This book will now help you set up and optimize SpamAssassin for your network.
Table of Contents (24 chapters)
SpamAssassin
Credits
About the Author
About the Reviewers
Introduction
Glossary

Chapter 3. Open Relays

Initially, the Internet was used by a very trusting community. Sites were open, with information freely available and shared. Passwords and user accounts were shared and even publicized. Email servers accepted emails from any source and sent them towards their destination. Nowadays, the ethos of the Internet has changed. Information is no longer shared as freely, and user accounts and passwords are guarded. It is rare to find a server that will take email from an unknown user and forward it on. This is a direct consequence of spam and the cost and risks associated with it.

Spam has become such a problem that ISPs terminate the accounts of spammers when they are reported. Consequently, spammers search for open relays, which are email servers that allow unknown or unauthenticated users to send emails. Once discovered, spammers use these mail servers to send spam emails. This approach prevents spam from being traced to its true source.

Running an open relay has serious...