A colocation center (also spelled co-location, or colo) or "carrier hotel", is a type of data centre where equipment, space, and bandwidth are available for rental to retail customers. Colocation facilities provide space, power, cooling, and physical security for the server, storage, and networking equipment of other firms and also connect them to a variety of telecommunications and network service providers with a minimum of cost and complexity. Configuration Many colocation providers sell to a wide range of customers, ranging from large enterprises to small companies. Typically, the customer owns the information technology (IT) equipment and the facility provides power and cooling. Customers retain control over the design and usage of their equipment, but daily management of the data center and facility are overseen by the multi-tenant colocation provider. Cabinets – A cabinet is a locking unit that holds a server rack. In a multi-tenant data center, servers within cabinets share raised-floor space with other tenants, in addition to sharing power and cooling infrastructure. Cages – A cage is dedicated server space within a traditional raised-floor data center; it is surrounded by mesh walls and entered through a locking door. Cages share power and cooling infrastructure with other data center tenants. Suites – A suite is a dedicated, private server space within a traditional raised-floor data center; it is fully enclosed by solid partitions and entered through a locking door. Suites may share power and cooling infrastructure with other data center tenants, or have these resources provided on a dedicated basis. Modules – data center modules are purpose-engineered modules and components to offer scalable data center capacity. They typically use standardized components, which make them easily added, integrated or retrofitted into existing data centers, and cheaper and easier to build. In a colocation environment, the data center module is a data center within a data center, with its own steel walls and security protocol, and its own cooling and power infrastructure. "A number of colocation companies have praised the modular approach to data centers to better match customer demand with physical build outs, and allow customers to buy a data center as a service, paying only for what they consume." Building features Buildings with data centres inside them are often easy to recognize by the amount of cooling equipment located outside or on the roof. Colocation facilities have many other special characteristics: Fire protection systems, including passive and active elements,