What are Referrer-Spammers?

When one visits a site, it is customary, although by no means mandatory, for one's browser to inform the site of the linking site. This data is placed in the referer-string and gets recorded in the site's server log. Site owners regard the referrer-string as one of the more useful bits of information, because they like to know who is sending them traffic. They may view the referrers in the site log or by viewing their site stats. Some site owners actually post a list of referring sites as an ill-conceived method of rewarding helpful behavior. I do not recommend doing so.

No verification of the referrer-string can be performed, because only the visitor and his ISP really knows where on the Internet he came from.  A referrer-spammer, typically a bot, inserts an incorrect link into the referrer-string in order to promote a site and tempt site-owners to click on the link. Once a site-owner clicks on such a link, he may expose his computer to a malware infection, and at any rate, his IP address and geographical location may be compromised. No reputable site would ever resort to referrer-spam in order to generate traffic. Only scum do that. When I detect referrer-spammers in my log, I add their IP address to my blacklist.

The day has long since passed when a webmaster trusted in hit counts as a reliable measure of popularity or readership. Hit counts are fun and offer a rough measure, but the number must be taken with a grain of salt. The lion's share of hits for less popular sites are bogus, but even popular sites receive plenty of bots. A site owner may trust in comments, shares, and link-backs as a firmer indicator of human traffic.

However, even some comments are the work of bots promoting sites, products, or people. During the election season, I receive my share of bots passing through posting a defense of a politician I may mention. When I blog about a brand-name, I may receive a comment defending the brand. I can sometimes detect bots when their comments do not strictly jibe with the content of my blog post. A bot may be triggered into dropping a canned comment by one or more keywords being detected in a blog post.

Looking over a site log can be a real eye-opener. The log reveals just how many bots there are out in the wild--comment spammers, old-fashioned email harvesters, referrer-spammers, content-scrapers, search engines of no good reputation, and bots probing for security weaknesses. If you are an English writer like me and you notice much traffic from Russia or China or some other far-flung place in the world, I wager you are seeing just a bunch of bots and nothing more.