Leaving the current 4th generation of mobile communications behind, 5G will represent a disruptive paradigm shift integrating access networks, ultra-high capacity access/metro/core optical networks and intra-datacentre network and computational resources into a single converged 5G network infrastructure. Thanks to an extensive deployment of network virtualization techniques leveraged by Software-Defined Networking (SDN) and Network Function Virtualization (NFV) technologies, such a 5G network infrastructure will have to be capable of inter-connecting anything anywhere and over a set of network services truly meeting their diverse communication requirements. In this paper, we overview the ALLIANCE project research activities. ALLIANCE ambitiously aims at architecting a converged 5G-enabled network infrastructure investigating several networking solutions such as SDN/NFV, OpenOverlayRouter (OOR) and the clean-slate Recursive Inter- Network Architecture (RINA) covering access, metro, core and datacentre segments. ALLIANCE relies on a Knowledge-Defined Networking (KDN) orchestrator which take advantage of state-of-the-art machine learning techniques to deploy, operate, monitor and troubleshoot networks automatically.