Do Subdomains Help with SEO?

Need information about using subdomains

[Holicc]

Hello,

I have a few questions about subdomains. I have never used them so I don't have any experience with it but a new client of mine wants to use them. Are there any advantages of using subdomains vs. html pages. This client would like to create a subdomain for each state they provide service in. I am just wondering if using subdomains can help or harm the site at all. What are the advantages or disadvantages of using a subdomain in terms of SEO.

Thanks in advance!

[tedster]

Here's my experience. A subdomain is, in many respects, treated like a completely different domain. So if you have a solid business purpose for a "new" domain, with some substantial UNIQUE content that will be updated and maintained in a normal fashion, attracting its own inbound links and so on -- then perhaps a subdomain is in order.

If this isn't the case, then the subdomains will probably be near-to invisible in searches and that content will probably be a bigger help in a directory on the main domain. In this case, it's the "unique content" that I would question. Is the information for each state really that unique and substantial? if so -- OK. If not, I wouldn't do it.

[Holicc]

From what I have read and the little I know about it, I agree with you. Thanks for the info Tedster.

[carminejg3]

tedster is right...

I had a powerful site all under one domain www.

once i broke the site out into 3 subs to section off my site the total power of main domain dropped....

because google does see
main site
sub1
sub2
sub3

as four different sites........ granted since pr is most likey for show since yahoo is still only a 9.

the sub domains may help you rank better under that topic. for example my one sub is "news" which is doing well, and serps seems to firmly believe its news related.

so if you are looking for a magic trick... ain't going to happen. if you are looking to split across serveral servers you could try using mod-proxy or sub domains

I would have stuck to one domain with sub folders if i could redo it simply because 100 links going to the main site, followed by 50 links going to a sub folder would really make it look like 150 links hitting the main site... even though 50 links where to a subfolder.

where now the 50 links going to the subdomain make that subdomain complete with the main site domain.

[obono]

I have some experience with this and perhaps can add to the administrator's perspective. Subdomains can be useful when considered as independent units, for example if you were to host all images in one of them and then decide to move that part of your site to another host for whatever reason. A subdomain gives you great flexibility because allows control of the DNS -unlike folders- and you can manage it as a completely different domain. They are also useful in that you can see stats independently so in this case, you might be able to track with more precision what happens on each state. This is more difficult when you consider stats for a domain as a whole. Such set up can also be helpful when considering translations say, for the latin market, an area that can be managed independently. You can even consider hosting this specific subdomain in local markets, depending on your objectives. Finally, subdomains can be useful when trying to protect your traffic if you weren't lucky enough to find the right host for your project. In case your service provider becomes unreliable and you decide never again to have all eggs in one basket, a subdomain set up may help in spreading that risk through other providers. If in the future you decide to branch out into other areas and want to isolate this new stream of traffic from any adverse effect on the whole, subds can shine.

However, a subdomain set up can present many disadvantages. Due to its own 'indepedent' stance it becomes much harder to create a navigational structure that makes sense. Although you could create subdirectories in the main domain grouping together the subs, you will still find it a lot harder than creating a directory structure stemming from main domain which may be a lot more appealing to the user.

There are other problems that need to be addressed when considering subdomains. If your site happens to grow large and it suddenly requires that you make changes across the board, including moving it as a whole unit or parts of it at a time (subdomains) you may face a real hurdle as you may have to replicate the set up somewhere else. Even in the best case scenario where you control the DNS and manage to make it a more flexible scheme you will be spending more time on the logistics than on creating useful content and attracting real links. And I haven't even touched the subject of working on the html pages themselves. A real problem if you require site-wide changes.

Lastly, subdomains have acquired a bad reputation in recent months/years. This will impact you whether you have the best of intentions. By using them, you will subject yourself to a lot more scrutiny both from competitors and search engine engineers. You may now think they are a solution but withouth a long term plan you may end up with one page subdomains later-to-be-developed that everyone will frown upon. You may never come close to know why they are being treated differently, you may never participate in forums and you may never understand its algo implications. Still, you will be found guilty. Even when performing any of the above needed changes. Because... why would anyone start moving subdomains around if not for...? A search engine engineer may understand complex programming but this doesn't necessarily mean understanding webmaster's daily problems. And in many cases, problems are being analyzed to see whether there is any malicious intent or not. When using subdirectories you have diminished this scrutiny greatly.

If you really cannot justify their existance with absolute confidence, then, folders and subdirectories will be a lot more appropriate for you. It is critical that you think this through or you may create a monster from which you may have a difficult time running away from.

[carminejg3]

like i posted above you should look into mod-proxy... if you need two or more servers... and want to avoid the subdomains

since they allow for you to use two servers and appear as one. also see apache docs

sitename/folder1/ server1
sitename/folder2/ server2