Why do I need to justify my requirements for an IP address?
It has been a growing issue for a number of years now that the number of IPv4 addresses available worldwide is rapidly diminishing. Due to the way that IPv4 is structured, there is a finite amount of these that will ever be available globally (4,294,967,296) and these will eventually run out. Due to this, we need to ensure that IP addresses are only allocated to those customers who have a technical requirement for them to ensure that there is availability where needed.
Justification is not just required to ourselves, but also to RIPE who are the European administrator of all IP addresses allocated within Europe. They have strict guidelines on the acceptable uses of IP addresses and we have to satisfy usage to them should this be checked.
What is not valid grounds for an IP address?
For many years, in order to have an SSL certificate on your website, this required that your site have its own dedicated IP address to support this. Advancements in software technology have meant that something known as SNI now means that this is no longer a technical requirement. This was one of the few reasons for users generally to need a dedicated IP address.
SEO companies have also often stated that search engine ratings are enhance if you have a dedicated IP address. There is no evidence to support this and this is not grounds for a dedicated IP address.
What is a valid reason for having an IP address?
As mentioned above, due to SNI there are few reasons to need this now. For a shared hosting environment, this should not be necessary at all now. For a VPS or dedicated server environment, aside from the server needing its own IP address which is allocated as standard, this may be justified in the requirement for setting up nameservers on your server as nameservers for a domain must be on differing IP addresses. Additionally, multiple applications on a server that may require use of the same port may therefore need separate IP addresses for communications.