This Recommendation aims to provide a network attachment control framework for an NGN evolution control plane (NGNe-cp) [ITU-T Y.2325] architecture that supports decoupling of the signalling handling functionality and the user plane control functionality in the control plane. In the NGNe-cp architecture, network attachment is considered a built-in service supported by using network attachment signalling service function (NASSF) and network attachment signalling service support function (NASSsupportF), which are detailed in this Recommendation. This is followed by a description of information flows for the network attachment process using the proposed network attachment control framework.