How to let Search engines index login-first SNS sites?

[DarwinChinaSEO]

What's the Effective way to let major search engine to index Login-first SNS sites? the reason of asking that is because i saw a search engines index Millon of SNS pages but most of them requested to login, how search engine get through this?

http://www.baidu.com/s?wd=site%3Akaixin001.com&pn=50

thanks

Boson

[sesertin]

hello Boson,

I can help you with google. The thing you are looking for is: first click free. You let anyone to access the first page of your content when getting to your site from the serps but request them to log in for the second one. You can do this with a session id. In depth: http://googlewebmastercentral.blogspot.com/2008/10/first-click-free-for-web-search.html