If you haven’t heard of referrer spam, don’t worry. You’re in the majority.
Referrer spam is a type of spamming aimed at search engines like Google, Yahoo, Bing and others that involve making repeated web site requests using a bogus refer URL, that actually is aimed at the site, the spammer wants to promote.
You may have heard of referrer spam by other names, which includes log spam or referrer bombing. Whatever they are called, all are considered to be “black hat SEO” strategies, or search engine optimization techniques that seek to exploit the weaknesses of search engine algorithms for commercial, financial or personal gain.
Here, then, are seven things you need to know right now about referrer spam and how it could be affecting your websites.
Why Websites Use Referrer Spam
If referrer spam is so dark why do people use it?
The reason is that sites that publish their access logs and referrer statistics will then inadvertently link back to the referrer spammer’s website. When that website is then indexed by search engines, as the search engine spiders crawl through these access logs, it shows that they have an artificially inflated number of links, which can push them up the search engine results pages (SERPs) for their keywords.
Is Referrer Spam Harmful to My Web Pages?
Not to be confused with viruses, Trojan horse software, or other potentially harmful online concepts, referrer spam is not harmful to your web pages or your computer. It won’t affect how fast your page loads, who can see it, or the way the content will appear to viewers.
The only negative effect referrer spam will have is on your site’s statistics because it can skewer them. This benefits the person doing the referrer spam because they get a free link, which can increase their search engine ranking.
One of the ways search engines like Google and Bing rank pages on their SERPs is by how many links lead to that page from other pages. The more links a web page has – especially from other pages the search engines consider to be authoritative or influential – the more weight that link is given and the higher the ranking may be.
What Web Pages Are Most Likely to Be Targeted by Referrer Spam?
Any web page is vulnerable to referrer spam, but authoritative sites are most at risk. These essentially are the places people go when they are looking for answers to a specific question or while conducting research. Examples include sites such as eHow.com, Answers.com, and Wikipedia.
Websites maintained by educational institutions and that have the suffix .edu also are generally considered to be authoritative sites, as are governmental websites that have the suffix .gov.
But referral spammers are non-discriminatory when it comes to aiming their black hat strategies at ordinary, everyday websites. As long as they get a backlink, they don’t really care where it comes from. Authoritative sites are just a bonus.
What’s New in Referral Spam?
In recent months, there’s a new type of referral spam that is making the rounds. It targets Google Analytics specifically and it is called “Ghost Spam” or “Referral Spam with 100% Bounce Rate”.
Ghost spam directly interacts with the data recorded on Google Analytics by targeting its measurement protocol system. In this instance, referral spam can directly influence a particular website’s traffic volume. This is because the primary objective of the referral spammer is to build traffic to their own pages – at the cost of anyone else’s web pages.
How to Protect Against Referral Spam, Part 1
Like any other type of spam, referral spam is easily blocked via a spam filter or spam blocker. Most email and security systems include these as a matter of course.
Web page owners also can actively seek out and prevent referral spam by preventing search engine spiders from crawling through their site logs. This is done by moving them to a non-public area of the website, such as a password protected page.
Another way is to use a robot exclusion file or appending the no-follow value to the links.
While most referrer spam simply distorts the analytics statistics for a particular web page, some newer versions will actually target the web server itself. While this won’t affect your site’s analytics, it could consumer server bandwidth. To protect against this type of referrer spam, you can block it using a .htaccess file or other specialized software.
How to Protect Against Referral Spam, Part 2
Using .htaccess files requires some in-depth knowledge of coding. But now there are some tools available for non-technical people to block referral spam automatically. Generally, these software tools are used for Google Analytics.
Referral spam is something you don’t really have to worry about unless your website depends on having accurate analytics.