A colocation provider will rent out space in a data centre in which customers can install their equipment, but will also provide the power, bandwidth, IP address and cooling systems that the customer will require in order to successfully deploy their server.
Futhermore, colocation providers deliver much more stringent levels of security, including security guards and even biometric access control. Resilience is another key feature, with data centres providing backups and UPS devices to protect against outages, including those caused by natural disaster, fire or flooding.
Space is rented out in terms of ‘racks’ and ‘cabinets’. A rack is a standardised frame for mounting equipment and hardware, usually horizontally.
Equipment that is to be mounted in a rack is measured in rack units (U), where one rack unit is 1.75 inches. The price for colocation plan is then calculated from the number of units required. A full size rack is 47U and is often called a ‘cabinet’. Depending on their budget and requirements, a customer can rent full, half or partial cabinets.