101 Articles Cloaking
CLOAKING (IP DELIVERY, USER AGENT CLOAKING)
Cloaking is an old tactic to cheat the search engines by showing a keyword rich content to the search engines but showing the users a different content. There are 2 types of significant cloaking tactics both for search engine benefit.
a.IP Delivery Cloaking: IP delivery itself is not a spam tactic. There are lots of reasons why you need to show different contents based on IP addresses. For example all top search engines detect users IP addresses and deliver them different results for geo-targeting. But that is a very valid reason but some SEO spammers deliver a keyword rich content website when the search engines crawlers crawl from their IP addresses. Mostly we call this IP cloaking not IP deliver. They get the IP addresses from whois information of search engine crawlers. Most search engines use the same IP range to crawl sites. But search engines are fighting back, they are crawling a webpage with IPs around the world. Search engine spammers are left in no man's land because they cannot discover where the search engines are coming from and which IP address they are using. If got caught of cloaking, penalties are severe and it is more difficult to get back into search engines.
b.User-agent Cloaking: User agent cloaking is the idea of showing different contents based on user-agents. Every browser / crawler is identified by a User-agent. Some of leading browsers and crawlers:
Internet explorer 6.0 , 7.0 , 8.0 -http://www.useragentstring.com/pages/Internet%20Explorerhttp://www.useragentstring.com/pages/Internet%20Explorer/Googlebot 2.1
Mozilla/5.0 (compatible; Googlebot/2.1; +https://www.google.com/bot.html)
Googlebot/2.1 (+http://www.googlebot.com/bot.html)
Googlebot/2.1 (+https://www.google.com/bot.html) Yahoo Slurp
Mozilla/5.0 (compatible; Yahoo! Slurp; http://help.yahoo.com/help/us/ysearch/slurp)MSNbot – MSNbot 2.1
What the spammers do is show a different content when they see any of the user-agents of search engines and show different contents for all other user-agents. This is a major spam SEO tactic and considered very aggressive and against the search engine guidelines. There are very rare cases where a user agent cloaking is done in an ethical manner with the permission of search engines. One place is webmaster world. If you check the robots.txt file of webmaster world (webmasterworld.com/robots.txt) they block virtually all crawlers from accessing the website.
Their robots.txt says
User-agent: *
Disallow: /
The above command tells all the search engines not to crawl any page on their site but check Google, yahoo, Bing they all have pages indexed from webmasterworld.com.
http://www.bing.com/search?q=site%3Awww.webmasterworld.com&form=QBLH&filt=all&qs=n
http://siteexplorer.search.yahoo.com/search?p=http://www.webmasterworld.com&fr=sfp
https://www.google.com/search?hl=en&q=site%3Awebmasterworld.com&aq=f&oq=&aqi=g5g-s1g4
so how is this possible?
Well webmaster world was loaded with 1000s of spam crawlers trying to steal content so what they did was blocked all crawlers from accessing their pages but allowed only specific crawlers identifying them by their User-agent. This gives exclusive access only to top search engine crawlers but all other crawlers were banned. This is a rare and valid reason of User-agent cloaking.
Brett tabke has permission from search engines to do this and its 100% valid. User-agent cloaking should be avoided by all possible causes since it will lead to a strong penalty from search engines. They like to show the users what they see not some other page that they don't see. If you see the webmaster world example they show the users what the search engine sees.
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Images |
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Screen Shots |
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Graphs |
The graph in the image shows that,the new visits are more and the repeated visits to a cloaked site are less because of the irrelevant content in the site.
The number of repeated visits in a cloaked site are very less when compared to first visits as the cloaked site is stuffed with unrequired keywords.
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Flash and Interactive stuffs |
A Video on Cloaking by Matt Cutts
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Source Code |
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Working Examples |
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References |
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Other sites that refer to the same manipulation tactic are as follows |