As i read few articles about new update of Google “white hat clocking ?” What is that ? Can anybody tell something about this new update ?
white hat clocking is a term for the privileged information say paid member’s area or flash content. Here the results shown in a search engine is actually hidden from a general search user and they are directed to another page or shown a flash or image.
Although technically it goes against the guidelines but then again the content is actually there, only you have to pay for it or you are viewing it through a different medium.
akh, are you sure? Redirecting to a login URL doesn’t sound like cloaking to me… it sounds like security protocol, and is typically BAD for SEO, because search engine spiders tend not to log in to your website before spidering. 
The only way I could see security equating to “white hat cloaking” is if the site stores a list of Google & other spider IP addresses and shows the privileged content when a spider is detected (for SEO purposes), but redirects to a “login” protocol if a non-spider user is detected (to maintain security).
EDIT: nevermind… seems that’s exactly what you said… I was just too thick-skulled to decipher what you said lol.
Cloaking refers to the practice of presenting different content or URLs to users and search engines.
Serving a page of HTML text to search engines, while showing a page of images or Flash to users.
Serving different content to search engines than to users.
Cloaking simply means serving two different contents to Search engine and for the visitors.
Cloaking in a wrong way may lead to get banned or penalzied by Google, there are some ways to cloak without getting banned. For eg; search for “gmail” in google. The URL you see in result will not match with the one you see after landing to the page. Many of these pages, whether you’re logged in or not, you might see some different content to what’s in the cache.
Cloaking is one of the most controversial strategies in search engine optimization.Major search engines publicly state that they consider all cloaking to be spam.But it has been using by many optimizers from long time.
Cloaking remains even today a much debated topic in the world of Search Engine Optimization. It’s basically that the information that actually presented to the search engine is different from what the users view in their browser. Google.com, Forbes.com, Amazon.com, etc all allow cloaking without penalty.