Canonicalization is a challenging topic of discussion. It’s hard to understand and maybe even harder to pronounce, but it’s an integral part of creating a web page optimized for search engines. Canonicalization fixes the problem of multiple instances of single pieces of writing on multiple pages on the same domain. The primary problem that is solved by canonicalization is the error stemming from the use of multiple single pieces of content (usually a paragraph or as much as a full page) appearing in multiple locations on one or more websites. In order to provide a positive user experience, duplicated content must be forced into a solution where one version remains.
SEO pages that can be loaded with multiple URLs present a problem for search engines. Canonicalization is a very common error, and it causes a page’s popularity to be split. This problem is more widespread because search engine and web servers have settings that create this issue. The most common canonicalization errors are produced when allowing the default settings to remain in force on the website server instead of inputting custom rules.
Web developers have created a method that redirects URLs and allows them to be changed or combined. There are two types of redirects for servers that exist. The HTTP status code 301 means “Moved Permanently.” The HTTP status code 302 is a temporary redirect. Link juice (ranking power) is not passed along to other normal links or server redirects in the Google network. There has been considerable testing on the subject of redirects and their impact on search engine rankings. The conclusion is that the 301 redirects pass along between 90 and 99% of the value of its popularity, but conversely, redirect 302 does not pass along any ranking value.
Canonicalization also includes characters that are alphanumeric and it dictates forward slashes in URLs. A common canonicalization error is the creation of an accident infinite loop. This problem is being solved by many search engines, but it is still important to mention that servers can automatically redirect 301 rom the older version without the proper slash that belongs in the correct version. This error allows a link that is pointing toward the incorrect version of the URL to lose almost 10% of its ranking value because of the faulty redirect 301. The solution and ultimate takeaway is that it is better whenever possible to handle the issue internally by linking to the version that has the backlash.
Another solution for this problem is the utilization of the rel=canonical tag that passes along an amount of link juice that is equal to the 301 redirect and takes up less time in execution. The HTML had of the tag is part of the web page. A nofollow command is not new nor is the meta tag, but using the new rel parameter is help in the solution to the error.
Microsoft Internet Information Services and Apache Web Services are two web servers that experience canonicalization errors. Google and Bing dictate that the page should be treated as if it were a copy of the URL. Also, the provided URL should be credited toward all the links and metrics associated with content that the search engine can apply.
<link href="http://www.123abc.com/canonical-version-of-page/" rel="canonical" />