The flood of new top-level domain names, such as .club, .luxury, and .pic, confuse some web browsers when they conflict with old domain names. ICANN has created a way to detect these problems inside your network.
I recently got a call from a friend whose business was having problems with an internal network whose web server had a URL that included .guru. One day, their staff had trouble reaching it. They'd made no changes and you could still reach the server using its IPv4 address; it was a mystery. It took me hours — and you still owe me guys! —but I finally discovered that there was a public internet website with a .guru top-level domain name that was conflicting with their private network. I gave their internal server a new Domain Name System (DNS), and all was well... after a few hours.
According to ICANN, which is also the organization that has blessed us with so many new TLDs to add to such old favorites of .com, .edu, and .org, states that "The framework is designed to mitigate the impact of name collisions in the DNS, which typically occur when fully qualified domain names conflicts with similar domain names used in private networks. When this occurs, users can be taken to an unintended web page or encounter an error message."
To address this issue, the framework calls for DNS registry operators to use a technique called "controlled interruption" to alert system administrators that there's a conflict. What will happen when a collision between a private and public DNS record happens is that the special IPv4 address, 127.0.53.53, will appear in system logs. This will let you quickly see where the problem lies so you can change the site name within your network.
The group is also working on a fix for companies and groups that have already moved on to using IPv6.
"We now have a well-defined methodology for mitigating name collisions for delegated top-level domain names and a path forward for registries to unblock certain second-level domains in their list," said Akram Atallah, president of ICANN's Global Domains Division in a statement.
If this sounds like more of a temporary patch rather than a real fix, you're right. That's exactly what it is.
In the meantime, ICANN registry operators are obligated to comply with requirements in the Name Collision Occurrence Management Framework. So, if a public web site with a name that includes a new TLD within its full URL causes a collision, the technical administrator of the new site causing the collision will be alerted so they can take action.
The Name Collision Occurrence Management Framework also calls for the delegation of .CORP, .HOME, and .MAIL to be deferred indefinitely. That's because these words are already commonly used in public domain names and domains using any these as TLDs would be all too likely to cause problems for existing web sites that incorporate those words within their URLs.