Search Engines Solve Canonical Issue

Finally a solution to tackle the duplicate content problem has arrived. Let's take a closer look at what exactly the problem is and what is the solution to tackle it.

Duplicate content is the nightmare of every SEO guy. Many webmasters are afraid of the content theft not because their creativity is stolen but Google will penalize them for having duplicate content on their site. Quite often webmasters get nervous about the duplicate content on the different pages of their sites although they are not at all responsible for it. It happens mostly with the dynamic pages whose contents can be viewed via different URLs due to change in things like sort parameters, category navigation, tracking id or session id and which are beyond the control of webmasters.

To overcome this problem major search engines like Google, Yahoo! and MSN have come up with the solution i.e. a simple link tag that too of a single line. If the website has identical content or vastly identical content which is accessible via different URLs, then this solution provides everyone more control over the URL to be returned by the search engines in their search result pages. This solution also ensures that the advantages such as link popularity are consolidated to the preferred version.

Suppose our preferred version of the URL is:

http://www.xyz.com/product.php?item=red-widget

However, users as well as robots can access the content of the above page via different URLs also such as:

http://www.xyz.com/product.php?item=red-widget&category=abc or http://www.xyz.com/product.php?item=red-widget&trackingid=1234&sessionid=5678

In order to avoid duplicate content issues, we need to add the link tag inside the head section of the duplicate content URLs. It will be like:



In the above line, rel="canonical" is a hint that Google follows strongly and will be taken into account with other signals when calculating the most relevant page to be displayed in the results page. But one must keep this in mind that Google will take canonical suggestions into account within a domain or across sub-domains but not across domains. Some other advantages of this solution are as follows:

• Relative paths can be used to specify the canonical.
• If rel="canonical" returns a 404 error then too search engines will continue to index the content and will use heuristic to find a canonical.
• If the canonical has not yet been indexed, Google will index it as per according to the working of its algorithm and will then consider the canonical tag.

The canonical solution given by search engines is a great relief for webmasters for whom the duplicate content issue was a nightmare as from now on they can easily specify the main URL but only time will tell how much usable the solution is or whether it is used by the black hats to derive some kind of advantage for their website. But, as of now it's a good solution for the webmasters to overcome the problem of duplicate content and for search engines to drop the unnecessary data from their servers thereby shedding some load.

I simply love the web. According to me, it's the most happening place in the world and the best place to interact and gain knowledge. My strong attraction towards site analysis from users as well as search engines perspective made me to pursue the career in Internet Marketing. I started as SEO but now I work as an Internet Marketing Specialist in a web development company based in India specializing in web 2.0 development and providing web design and development services to the clients globally.
The company provides website design and web development services for range of websites utilizing the power of latest technologies like - .NET, PHP, Ruby on Rails (RoR), Silverlight and SharePoint to name a few.