well these are web 2.0 blogs like (wordpress, blogger, weebly, jigsy, jimdo, could be press release sites ) this is like creating a ozone layer for protection . and these blogs/pr (what ever you like to use as your buffer) will have a link to your money site(your domain) so if you cant risk to loose your website or you think your website is not really that old/strong then you can point links to your buffer which will pass link juice to your main site . for more information try searching for link wheeling or link tier diagrams on google