Cloaking – the unethical uses
Not all cloaking is bad despite the oft-heard cries that cloaking will get you banned but if you use cloaking in an attempt to deceive the search engines you can expect trouble.
Cloaking is often used as an acronym for using scripts or programs to show one page to search engines and quite another to viewers. Since search engines want their rankings to be based on the page which the viewer sees, this tends to distort the relevancy of the page to the rankings it receives. Search engines frown on all attempts to deceive them and will most likely remove your site from their index if they find you using cloaking to deceive them.
Cloaking – The ethical uses
Like most tools cloaking can be used ethically and usefully and in most cases, search engines have no problem with such uses, and in fact, often use cloaking and redirects themselves. If you use a script to detect what browser your viewer is using and based on that show a slightly different page to viewers using that browser, this should not be a problem and likewise detecting the location or language of a user and redirecting to pages created for that location or language is an ethical scheme which is used to improve the user experience.
I realize that there will be many who will disagree with my suggestions here that there are any ethical uses for cloaking, but you will find on examination that search engines themselves employ cloaking to redirect users to various national and language sites in order to improve the user experience.
Doorway pages are antiquated
Back in the dark days when search engines were slowly groping their way to relevancy, it seemed that every search engine had a different algorithm and what worked for one search engine would not work for another. These days all the search engines are using some combination of on-page content combined with link popularity and anchor text links to rank their results.
Back in those days webmasters often resorted to building several pages on any one topic, each of them optimized in the fashion of the day for one popular search engine.
Every page a doorway page
Today the arguably most important search engine is Google which uses again a combination of on-page content analysis, with PageRank link popularity and a strong emphasis on inbound anchor text links to produce their ranking results. I find that pages that are optimized to rank well in Google will usually rank well in both Yahoo and Bing, which taken together covers 90% of the search engine market. You do have to do things like add meta description tags and keywords meta tags to help to rank in the last two engines and you will need more anchor text links to rank well in Google, but if you do your optimization for Google correctly you should rank even higher in these other search engines.
Following the KISS principle, I believe that doorway pages are well… err as dead as a doornail.
Be sure you clearly understand the do's and don'ts of cloaking before you attempt to use it.
If you have any questions make sure you are clear and certain on the likely search engine reactions or else don't do it.
The Fantomaster site is perhaps one of the best on the web with regards to cloaking. If you have questions regarding cloaking that may be a good place to go for answers.
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