Authority Domains and Sub-Domains

Does Google pass authority to a new site on a subdomain?

[keepclear]

I know that Google treats sub-domains as separate websites, but if I was to start a new site on a semi-similar subject to the main domain on a subdomain, Would this site have to build up authority and possibly be sandboxed?

I would be linking to the sub-domain from the main website, also possibly be showing headlines via RSS.

Any help, examples would be appreciated.

[Crush]

Yes subs get the trust from the main site. Altough with the recent parasite hosting issues subs can also be zapped. If you look all over the serps you will see lots of subs piggybacking from the root domain.

[keepclear]

Excellent news,
Do you know if a different subject on a sub-domain would affect the rankings of the main domain- I dont want to dilute the main site as it has excellent serps.

An example (loosely related subjects)
- Main domain subject : Design
- Sub domain subject : Computers

[sandpetra]

What would be the immediate benefits or risks of adding a subdomain to your trusted site then (as opposed to throwing it in a plain old sud-directory?

[minnapple]

Keywords in the subdomain name helps rankings, as long a the main domain fully supports the subdomain.

[synergy]

What would be the immediate benefits or risks of adding a subdomain to your trusted site then (as opposed to throwing it in a plain old sud-directory?

Last week I moved a subdirectory-based broad topic blog to a new subdomain. Why? I felt like the broad topic blog was diluting the niche topic of the main website. You have to ask yourself, at what point do the scales tip and Google begins seeing my site as being about broad topic A rather than niche topic B? Niche topic B pays the bills, so obviously I had a dilemma on my hands. Moving the broad topic to a new subdomain (and essentially a new website in Google's eyes) should allow each topic to grow unimpeded on their own terms.

I see no risk associated with it, unless the topics are completely unrelated.

[keepclear]

Nice one Synergy - thats what I was worried about, diluting the main domain.

Thanks for your help.

[pageoneresults]

Sub-domains are one level above the root domain. Sub-directories are one level below the root domain.

Sub-domains are perfect for a site where there is a very "diverse" line of products and/or services. Its a perfect setup for a site that has totally unrelated categories.

Be careful though. Fiddling in the sub-domain space and not having a site to fully support the breadth of the sub-domain structure, may present issues.

Does Google pass authority to a new site on a subdomain?

Actually you have some say so in this too. Link paths will determine how much juice you can pass from the root to the sub and vice versa. ;)

[Robert Charlton]

Keywords in the subdomain name helps rankings, as long a the main domain fully supports the subdomain.

Would this actually be any different if there were a directory structure instead of a subdomain structure?

I've always doubted that domain names or filenames by themselves helped boost rankings. I've thought instead that the ranking boost depended on whether they were used in anchor text. I'm asking the same question here.

Is a keyword anchor link from the main domain to a keyword-named subdomain inherently more helpful than an internal nav link within the same domain?