TThis European Standard specifies generic cabling that supports a wide range of communications services for use within a data centre. It covers balanced cabling and optical fibre cabling. This European Standard is based upon and references the requirements of EN 50173-1. This European Standard contains additional requirements that are appropriate to data centres in which the distance over which communications services have to be distributed is the maximum defined for backbone cabling implementations within EN 50173-1. The principles of this European Standard may also be applied to installations that do not fall within this range. In addition to the requirements of EN 50173-1, this European Standard specifies: a) a modified structure and configuration for generic cabling within data centres used to support existing and emerging applications; b) implementation options to reflect the quantity of connections required in data centre infrastructures; c) requirements that reflect the range of operating environments within data centres. Safety (electrical safety and protection, fire, optical power etc.) and electromagnetic compatibility (EMC) requirements are outside the scope of this European Standard and are covered by other standards and regulations. However, information given in this European Standard may be of assistance in meeting these standards and regulations.