Mobility in a wireless heterogeneous scenario in which the mobile devices are able to connect to more than one access technology requires a new architectural development for the network connectivity management. The present paper describes and evaluates a set of architectural options for integrating the novel network discovery and selection functionality in the 3GPP evolved packet core which enables an operator to manage the connections of the mobile devices. As the design options here presented consider different levels of network control on the mobility at the cost of new interfaces and new procedures, an evaluation based on these two criteria is given.