Do backlinks from subdomains positivly effect page rank?

[Nastra]

If they do it could be very beneficial to use available subdomains to link exchange and promote the main site. As with my site it may be unprofessional looking to do link exchange on the main domain. Any additional thoughts on that? This maybe an old technique, I have just in the past week been getting into engine optimization.

Any thoughts would be greatly appreciated.

[flood6]

Most will agree that Google discounts or disregards IBLs from sites hosted on the same or similar IPs. Some say that if this is done too extensively you could get penalized.

There has been quite a bit of discussion about this in the past around here, do some searching and you should find some good opinions and experiences.

Good luck.

[Tjaart]

My understanding of your question:

You want other websites to link to your main domain (www.domain.com), but you would prefer to link back to them from sub-domains (xxx.domain.com) rather than from your main domain. Correct?

You will therefor have no or very little inbound links to your subdomains?

If this is all correct, I can see no problem with what you are doing except that your main domain will have a high PR and your sub-domains a much lower PR. This is good for you, but not good for the other websites that you link to. I think many websites will not want to link to you because the sub-domains linking back to them will probably have a much lower PR than the main domain they link to. They could potentially get 'stronger' links back from your main domain than from your sub-domains.

Many will not see it as a fair exchange.

If the linking pages on your sub domain has high PR, websites should be OK with what you want to do. But then you also have to get inbound links into your subdomains to increase the subdomain PR.

Hope this helps and makes sense.

Tjaart
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