The data center is divided into multiple different levels of distribution areas: the main distribution area (MDA); Intermediate Distribution Area (IDA); Horizontal Distribution Area (HDA); Regional Distribution Area (ZDA); Equipment Distribution Area (EDA).

The main distribution area includes the main cross connect (MC) distribution equipment, which is the central distribution point of the structured cabling distribution system in the data center. When the device is directly connected to the main distribution area, the main distribution area may include wiring devices with horizontal cross connections (HC). The main distribution area can serve one or more intermediate distribution areas, horizontal distribution areas, or equipment distribution areas of data centers in different locations, as well as telecommunications rooms outside each data center, with the support of routers, core switches, core storage area network switching equipment, and PBX equipment in the core of the data center network. It also provides services and support for office areas, operation centers, and other external support areas. Sometimes communication equipment (such as communication transmission facilities) connected to telecommunications operators are also placed in the area to avoid exceeding the rated transmission distance due to cables. The main distribution area is located inside the computer room, and to improve security, it can be set up in a dedicated space inside the computer room. Every data center should have at least one main distribution area.