One of the hosting companys I work with does provide IPs with different C blocks. I actually got sites with different C blocks hosted with them. Im not going to post the name here but its one of the larger US based ones.
I must say that after playing around with the linking between sites on different A and C blocks, I dont think thats the big issue. Its more important how you do the linking between the sites. Simple math can show why reciprocal linking is less valuable for PR then other, but remeber, link popularity is important. I do belive that its the excessive linking between peoples own sites hosted on the same IP with few other links that gives problem. If the majority of your links comes from the outside (different C and A) then a few links on the same C block wont make any difference.
I have close to 100 sites hanging on one of my IPs, there is some linking between a few of them, some more then others but in a manner that makes sense. This has not caused any problems. A few of the sites on that IP is recieving high rankings and good traffic for some keywords that arent that easy to rank for.

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Mobile Marketing

Hello Guys I have a similar question I am faced with currently.

I am considering having my main domain that is currently a yahoo store and the way Yahoo does there ecommerce they have both www.domainname.com and store.domainname.com if I move the www. to an entirely different host it would be on a different IP block and keep my Yahoo store that is currently store.domainname.com

If I change the address of the store. to another domain name it would look like they were two entirely separate sites. I would however have the www. currently my content site with links going to the store. (New Domain Nam) site but it would not reciprocal linking back.

Now that I have confused everyone. Could this happen?

Content Site + Store Site Both in the Search Engines?

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You can have them both in the search engines if there on the same IP address..... The store is on a subdomain..... That's fine....

It will actually be easier for you to get the subdomain indexed off of the main site.....

And your page rank should flow to the subdomain easily....

Build links to both your main site and your store....

You'll be fine... I see no real reason to go with a seperate host for that....

Anyone disagree?

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I know that SE's tend to check the IP's. There are 2,097,152 (21 squared) Class C networks with each 254 (2 power of 8 – 2) possible hosts for a total of 536,870,912 (2 power 29 unique IP addresses. That said, block C only makes up 1/8th of the total available IP addresses.
This means it becomes a ludicrously large number of possibilities, and if every website linking to a partner made sure it was on a different block, it would simply be expensive and unproductive.
It is true that part of the Google algorithm will check against IP’s as part of a checking mechanism that is fired when enough criteria are filled.
As long as the correct methods are used to optimise websites and that these are legitimate, there is no reason to fear penalisation through IP.
However we have had some problems because our URL is a .com, and our IP is registered under a french IP, meaning that we find it difficult to rank in regional listings.

Cool Thanks, the reason I am also asking this is because back at the end of June 2004 the googlebot spidered our site and at the time I had around 1500 links for choppersapparel.com and now have 6 listed as the www. the rest of them are the store.

As for all the other search engines I am listed in yahoo, msn and others as the www. not the store. that is why I am considering different host providers for content vs. store.

__________________
Please do not take my word for fact, its only my opinions and you really need to research more before you make major changes.
Peace of mind for your online marketing.

BCC Enterprises Merchant Solutions | Fishing Tackle Reviews

Fro experiance I have had success with just using colo servers in different locations. By doing this most IP's are on seperate class A's in fact if you live in a large city you can find at least 4 colo places that not only have seperate class A's but also can give you 20-50 IP's on 2 or 3 class c's.

My question is why is google not check MAc Addresses or DNS info that would seem to reveal SPAMMERS a mile away.

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You are not wearing your avatar, but your signature is giving you away...lol

Welcome to the forum Balthazar

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I added a more powerful avatar here...their are some who call me ....tim

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