5G networks: End-to-end architecture and infrastructure [Guest Editorial]

Tubiquitous ultra-broadband network enabling the future Internet (FI), is not only about new releases of current network generations and services, but, more significantly, will be associated with a true revolution in the information and communications technologies (ICT) field: the network will efficiently and effectively take forward new-fangled services to everyone and everything, such as cognitive objects and cyber physical systems (CPSs). A "full immersive (3D) experience" enriched by "context information" and, in particular, "anything or everything as a service (XaaS)" are the main business drivers for massive adoption and market uptake of the new fundamental enabling technologies, beyond today's "client-server" model, where the network has been reduced to a ubiquitous "pipe of bits." XaaS refers to those services — beyond the current models of software as a service (SaaS), infrastructure as a service (IaaS), and platfore as a service (PaaS), SPI models, of cloud computing — such as data as a service (DaaS), security as a service (again, SaaS), network as a service (NaaS), knowledge as a service (KaaS), machine as a service (MaaS), and robot as a service (RaaS), which could be delivered over the advanced 5G infrastructure, without the need to own hardware, software, or even the cognitive objects themselves. Communication services, such as voice and video telephony, will be enriched and bundled with other services. The network infrastructure is expected to become the "nervous system" of the actual digital society and digital economy. This challenge calls for a complete redesign of services and service capabilities, architectures, interfaces, functions, access and non-access stratum protocols and related procedures, as well as advanced algorithms (e.g., for unified connection, security, mobility and routing management, and reconfiguration of ICT services; and any type of resource of cyber physical systems). The expected transformation will be especially true at the edge, that is, around the end user (or prosumer), where the "intelligence" already started migrating a few years ago, and where massive processing, memory, and storage capacity are gradually accumulating.