Shadow Domains and Search Engine Optimization
Shadow domains can be used to quickly fabricate false rankings within search engine results. Its practice is not to be recommended as the most popular search engines look at it with disfavour and judge it as search engine spamming.
Shadow domains are when different domains are used to create various web addresses (URLs) which redirect users to the real target website on a primary domain. These shadow domains have lots of pages that are optimized with desired search phrases and keywords. The pages are not intended for viewing by normal users and are said to be “cloaked” from human viewing by redirecting users transparently to the real website. The pages on shadow domains do not have to be user friendly and as they are not intended for viewing by humans they can contain extremely optimized content that is specifically designed to get the best results from search engines crawlers. Whereas users are redirected immediately from the shadow domains to the more user friendly website on the primary domain, search engines will process all the content on the shadow domains, so increasing their ranking within the search engine results.
This sort of technique is greatly disapproved of by respected search engines (those your website would like to be found in) and will result in the loss of both the primary domain and shadow domains position within search engine results once discovered or when someone reports it. Possibly even removal of all the domains in question if the practice is continued.
WARNING. We have even seen a variation of this technique used as part of a cyber attack against a domain with an existing high level organic (non-paid) ranking in search engines. The target site’s content was copied (using a technique called “content scrapping”) onto multiple websites with different web addresses using shadow domains, these websites transparently redirected users back to the website being targeted in the attack. These shadow domains were then crawled by search engines, however once the search engines became aware of the potential malpractice, all the domains, including the target domain, were penalized and dropped from the top of the search engine results. A high organic position that took years of SEO work to achieve was destroyed in a very short time. If this happens to your website, report the attack immediately to the technical support teams of organizational bodies involved (eg. search engines and hosting ISPs). Preferably before the search engines notice it themselves and remove your domain from their results. This form of attack can be verified by checking the referrer entries in your website analytical reports or log files. The referrer stats or entries can be use to investigate where traffic to your site is coming from and if it is valid. Look for unusual domain names, sometimes utilizing keywords important to your website and find in your “keywords” meta tag.