An Enterprise Data Center consists of multiple data centers, each with a targeted focus on sustaining key functions. These data centers can be classified into three types: internet, extranet and intranet.
Internet data centers are a category of enterprise data centers that support servers and devices necessary for e-commerce web applications. In some cases, web servers are completely isolated from the rest of the network at the physical level. These servers have no physical path to any other part of the network, with the exception of a direct connection to the intranet data center using a separate set of non-routable links.
Extranet data centers provide support for business-to-business transactions in the enterprise network. These services are generally accessed over secure VPN connections or private WAN links.
Intranet data centers contain the infrastructure that holds applications and services in an enterprise data center network. They often encompass support functions for manufacturing, marketing, HR, research and development, payroll and other core business functions.