The present document specifies the optical cabling in a building when it is shared between multiple optical access operators. The proposed building cabling allows access to each operator to optical fibres in the building for multi-dwelling units (MDU). The main goal of the concept is to be able to share the optical building cabling among different optical access operators. The present document details the different architectures of a shared optical cabling and each element of the building cabling. These elements are the distribution point@ the indoor building cabling and the optical termination at the customer premises.