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Introduction to spam

Since the World Wide Web was created, resources have become more accessible and flows of information circulating on the network of networks have continued to increase. However, the content of this information has not always advanced in the right direction and many people have quickly learned how to wrongly make use of these resources.

"Spam" (the term junk mail is also used) refers to the sending of unsolicited bulk e-mails.

Concept of spam

The term "spam" is used to describe the sending of bulk e-mails (often advertisements) to recipients who have not solicited them and whose addresses have generally been found on the internet. The word "spam" comes from the name of the lunch meat sold by the company Hormel Foods. The association of this word with abusive e-mails comes from a Monthy Python sketch (Monty Python's famous spam-loving vikings) that takes place in a viking restaurant whose speciality is Spam. In this sketch, whenever a customer orders a different dish, the other customers start to sing "spam spam spam spam spam..." in chorus so loud that the poor customer can't be heard!

People who send bulk advertising e-mails are called "spammers", a word that now has a pejorative connotation!

Why spam?

Spam's primary goal is to advertise at the lowest price via 'junk mail" or "excessive multi-posting" (EMP).

Spammers sometime claim, in bad faith, that their recipients have spontaneously signed up to their database and that the received e-mail is easy to delete, which is after all an environmentally friendly way to advertise.

How spammers work

Spammers collect e-mail addresses from the internet (in forums, on websites, in discussion groups, etc.) thanks to software programs called "robots" that browse the various pages and store all of the e-mail addresses that appear on them in a database.

At this point the spammer only has to launch an application that successively sends each address the advertising message.

Spam's effects

Spam's major drawbacks are:

• the space it takes up in victims' mailboxes;
• difficulty consulting personal or professional messages mixed in with the various advertising messages and an increased risk of mistakenly deleting or not reading important messages;
• time lost from sorting and deleting unsolicited messages;
• the violent or degrading nature of the texts or images conveyed through these messages, which may be shocking to young people;
• the bandwidth it wastes on the network of networks.

Spam also generates additional management costs for internet service providers (ISPs), which are reflected in the cost of their subscriptions. These additional costs are mainly related to:

• the set-up of antispam systems;
• user awareness-raising;
• staff training;
• the use of additional resources (filtering servers, etc.).

Fighting spam

Spammers usually use fake addresses, so it is totally useless to respond. What's more, a response can show the spammer that the address is active.

Likewise, when you receive a spam (junk mail), a link at the bottom of the page may give you the option of no longer receiving this type of message. If this is the case, it is very likely that the link will make it possible for the spammer to identify active addresses. You are therefore advised to delete the message.

There are also antispam systems that make it possible to detect and, when needed, delete undesirable messages based on advanced rules. Antispam software is generally categorized into one of two types:

• Client antispam systems, used by the messaging client. These generally are systems featuring identification filters, based on predefined rules, or learning filters (Bayesian filters).
• Server antispam systems, which can filter mail before it is delivered to recipients. This type of system is by far the best since it makes it possible to stop the junk mail upstream and avoid flooding networks and mailboxes. An intermediary solution involves configuring the server's antispam system so as to mark messages with a specific header (for example X-Spam-Status: Yes). Thanks to this marking, it is easy to filter messages at the messaging client level.

In the event that a mailbox is overloaded or fully saturated, the final solution is to change mailboxes. You are however advised to keep the old mailbox during a sufficient amount of time so as to recover your contacts' addresses and be capable of communicating your new address only to legitimate individuals.

Avoiding spam

To avoid spam, give out your e-mail address as little as possible and in addition:

• Do not pass on messages (jokes, etc.) asking the user to forward the e-mail to as many contacts as possible. Such lists are actually godsends for address collectors. You may possibly transfer the message if you make sure to hide the previous recipients' addresses.
• Insofar as possible, avoid publishing your e-mail address on forums or websites.
• Whenever possible, replace your e-mail address with an image (not detectable by address harvesters) or break it down (for example "john dash frances period parker at commentcamarche point net".
• Create one or more "disposable addresses" you use only to sign up or log in to sites considered non-trustworthy. The epitome of refinement, when you have the possibility, involves creating as many alias addresses as registrations while making sure you note the name of the company or site. Therefore, if you receive an unsolicited e-mail, it will be easy to identify the source of the "information leak".