A jump/doorway page is like an entrance page or splash except that there are multiple versions of it distributed across the internet. A link to your home page will be provided on a page specific to what you are searching for. Typically a jump page is not optimized for content, but for search engine rankings. They are often "keyword rich" around a specific subtopic. For instance, if your site is about celebrity gossip, then you would have a jump page for every celebrity you gossip about with little keywords such as "new boyfriend" "court date" "pregnant" etc. thrown into the page in a garble.
Another type of jump page is the redirect page. This is obsolete as search engines pick up on the javascript and meta tags and choose not to list your site. Ouch. The only redirect now accepted is the 301 redirect - meaning that your site has moved permanently to a different location.
So how can I get away with it?
The search engines want good, clean, new content on respected websites. Duplicate content is ignored. "Keyword stuffing" (having a page with a high density of keywords) is considered spam. This means that every one of your jump pages has to provide valuable information for the user. Also, you have to be willing to market and advertise every single one of those jump pages. That is a lot of work.
Is it even worth it?
There are many better ways of link building that take a lot less time and effort. Simply having quality blogs and updated content, being present in your niche, posting valuable content on other websites with a link back to your site is a much better use of your time than building a jump page empire.
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