Spam or junk refers to unsolicited electronic messages that often have an advertising character. The increased volume of messages and the additional work required to sort out or process them cause considerable economic damage.
What is Spam?
Spam, often referred to as junk, is unwanted messages sent electronically, such as e-mails, SMS, or forum messages. The recipient receives the messages without having given their consent for this. The content of the messages is often of a commercial and advertising nature. However, they can also be phishing messages or messages with attached malware such as viruses and Trojans.
Some spam messages have no content at all or have meaningless content. The process of sending is called spamming. The senders of the messages are spammers. Junk messages can be compared to junk mail. If the unwanted messages are e-mails, alternative terms are Unsolicited Bulk E-Mail (UBE) or Unsolicited Commercial E-Mail (UCE).
Spam emails are the most common junk messages. Therefore, many equate the term spam with unsolicited email. Other forms of spam include advertising banners and pop-ups that open unwantedly when you visit a website.
Negative impact of spam
Junk messages cause huge economic damage worldwide. Sending messages requires bandwidth on networks and generates additional processing overhead. Reading and sorting out costs working time. If the manual effort is to be reduced, additional technical measures such as spam filters must be installed and maintained.
On the Internet accesses, the messages occupy bandwidth that is no longer available for other applications. The mail servers also have a higher load due to the additional messages. If there is a high volume of junk messages, the servers may even fail completely. To avoid this, more powerful hardware must be installed. Also not to be neglected is the additional energy consumption caused by the junk messages. It is estimated that well over 90 percent of all e-mail messages worldwide are spam.
Use of spam filters
A technical measure for sorting out unwanted messages is the spam filter. Spam filters can be installed locally and be part of an e-mail program or be provided by the e-mail provider on the network side. Spam filters are maintained by the user of the e-mail program or by the provider. The filters detect junk messages based on certain characteristics and sort them out automatically. As a rule, the filter moves them to a separate directory, which the user can view if necessary.
Messages that have been mistakenly sorted out can still be read. There are numerous intelligent algorithms that automatically maintain the spam filters and reduce the maintenance effort for the user or provider. Spam filters directly at the e-mail provider have the advantage that e-mails are sorted out before they are delivered to the user. This means that they do not occupy any bandwidth on the Internet connection and do not clog up local mailboxes. A combination of local and network spam filters offers particularly good protection.
Criteria according to which spam filters sort out unwanted messages are, for example:
- Known IP addresses of spammers
- Conspicuous sender addresses
- Conspicuous text in the content or subject line of an e-mail
Spam filters are usually based on anti-spam lists, some of the best known of these lists come from the Spamhaus project. Intelligent spam filters can learn independently, for example, by users marking messages as spam and the filters automatically recording the relevant criteria.
