Referer spam

Referrer spam (also log -spam) is a special form of spamdexing. These websites are called en masse, so that they appear in the referrer information of the statistics of the attacked sites.

Background

Many search engines give a website a good position if many links point to this site. In addition, many websites evaluate the referrer to analyze, for example, where the user come. This is usually done on the basis of Logdateianalyse. If they are shown online - what's popular is particularly important in Blogs ( cf. backlink ) -, it is interesting for spammers to perpetuate themselves in these Referrerlisten, since it is assumed that these Web statistics from web crawlers read and used for ranking in search queries be.

Damage

Through this form of spamming damage for the website operator arises in two ways. Firstly, the relevant information for the interpretation of the log files are corrupted, and on the other hand generates additional data traffic in this way. On the side of search engine operator enters a damage in respect of thereby falsified search results.

Legal consideration

In commercially operated sites, one can assume that an interference with the right to an established and functioning business comes through this form of spamming that threatens the availability of the server into consideration. Theoretically, one could construct a private law claim of self-presentation on a website and understood as manifestation of the general right of personality for private pages. Any criminal matters arising analogous to spam. The problems arising in this context whether referrer spam is even advertising, as that is the case, at least in terms of published Logdateianalysen and resulting improved search engine rankings, sometimes beyond.

Defense mechanisms

Nofollow

A simple, albeit only partially effective solution, the use of the rel = "nofollow " attribute, which means that such references can not be used to calculate the PageRank would. That this does not affect the behavior of spammers and their number is not reduced, now seems proven.

. htaccess

One possibility, the referrer spam to halt would be a bad words list with RewriteCond in an. Htaccess file ( Access Forbidden ) status 403 sends when another word appears in a referrer.

RewriteEngine on RewriteCond % { HTTP_REFERER } casino [ OR] RewriteCond % { HTTP_REFERER } poker. RewriteRule * - [ forbidden, last] Alternatively, one can restrict the problem with the SetEnvIfNoCase.

SetEnvIfNoCase User-Agent " IzyNews/1.0 " leecher = yes SetEnvIfNoCase Referer izynews.de leecher = yes order deny, allow deny from env = leecher The problem is in this regard that one must supplement the bad words list manually. One approach would be extended, with a web-based scripting language to record the referrer and evaluate how often referrer occur within a certain time. Exceeds the access from a particular page, the predetermined amount, the referrer will be automatically entered in the htaccess. , And cleans up the log file with a cronjob. In this regard, it is difficult to determine that an increased traffic is allowed from a specific page. A similar approach is the Apache module mod_evasive.

Report

Search engine providers have often appropriate boundary conditions set where paid links and other undesirable methods are specified as exclusion criteria from the index. Therefore, it can help the detector, with corresponding log excerpts to report the spam origin domains in the search engine operators as evidence because they can be removed from the index when several complaints / reports received from various sources. This is likely the " advertising strategy " be a boomerang for the spam bot operators and spammer domains, because the exact opposite of the intended effect occurs. The ranking and the list items do not rise, but the domains are banished from the hit lists.

Other Approaches

In addition, there are other approaches that prevent using a built- into the corresponding site php script spam.

Swell

• World Wide Web
• Internet Law
• Competition Law
• Internet
• Web Development
• Search Engine Optimization