Does Link Juice Trickle?

Or Is it contained on a page-by-page level?

[cabbagehead]

I am debating a site archicture and curious to hear opinions from a page rank perspective:

[blog.xyz.com...]
[xyz.com...]

...I prefer to install my blog in a seperate subdomain because its technically a different webapp and its clean. But I wonder ... if I get ppl linking to my blog, might the overall www benefit from trickle-down link juice? It is my assumption that link juice is primarily a page-by-page phenomenon but that there is some transference to the site as a whole.

Any thoughts?

[buckworks]

The flow would entirely depend on how your links were structured.

What links to what?

[cabbagehead]

Well, let's say the blog has a couple of links to the main site:

blog.xyz.com -> www.xyz.com

...if I begin to recieve inbound links to blog.xyz.com, does the link juice from those inbound links trickly to www.xyz.com at all? Is it improved if it is under the same umbrella: www.xyz.com/blog/?

[martinibuster]

The amount that trickles back from subdomain.example.com to example.com is relative to the amount of links you have pointed back from the subdomain to example.com.

Same thing applies to example.com/blog/.

My rule of thumb is that creating a subdomain makes sense to users if what you're offering is very different than from what's on your main site. travel.yahoo.com is different from yahoo.com is different from autos.yahoo.com, right?

autos.yahoo.com/bmw/ makes sense, right?

[cabbagehead]

yeah. I'm torn I guess given your principle cuz content-wise it sounds like I should keep it all under one umbrella. Technology wise though - www is a java app while blog. would be a php app. Yes, they could co-exist under www but putting the two together for me is like nails on a chalkboard. Just trying to see if there may be benefits to outweigh this personal preference before moving forward I guess. From what you're saying however - it would not matter - all would be equal?

[Kirby]

Use the sub-domain.

[martinibuster]

The subdomain seems cleaner. You will be able to do this:

blog.example.com/php-software/

blog.example.com/php-editors/

blog.example.com/php-hosting/

Looks orderly and organized.