Page 13 - ITU Journal Future and evolving technologies Volume 2 (2021), Issue 6 – Wireless communication systems in beyond 5G era

ITU Journal on Future and Evolving Technologies, Volume 2 (2021), Issue 6

WHY DO WE NEED 6G?

1
1,2
Riccardo Bassoli , Frank H.P. Fitzek , Emilio Calvanese Strinati 3
1 Deutsche Telekom Chair of Communication Networks, Institute of Communication Technology, Faculty of Electrical and
2
Computer Engineering, Technische Universität Dresden, Dresden, Germany, Centre for Tactile Internet with
3
Human‐in‐the‐Loop (CeTI), Cluster of Excellence, Dresden, Germany, CEA Leti, 17 rue des Martyres, 38000 Grenoble,
France,
NOTE: Corresponding author: Riccardo Bassoli, riccardo.bassoli@tu‐dresden.de

Abstract – The study and design of 5G seems to have reached its end and 5G communication systems are currently under de‑
ployment. In parallel, 5G standardization is as Release 16, which is going to complete the de inition and the design guidelines
of the 5G radio access network. Because of that, the interest of the scienti ic and industrial communities has already started
focusing on the future 6G communication networks. The preliminary de inition of future technology trends towards 2030,
given by major standardization bodies, and the lagship 6G projects worldwide have started proposing various visions about
what 6G will be. Side by side, various scienti ic articles, addressing the initial characterisation of 6G, have also been published.
However, considering the promises of 5G, can 6G represent a signi icant technological advancement to justify a so‑called new
generation? In fact, now, 5G softwarized networks may just imply continuous network software upgrades (as it happens for
the Internet) instead of new generations every ten years. This article starts describing the main characteristics that made 5G
a breakthrough in telecommunications, also brie ly introducing the network virtualisation and computing paradigms that
have reformed telecommunications. Next, by providing rigorous de inition of the terminology and a survey of the principal
6G visions proposed, the paper tries to establish important motivations and characteristics that can really justify the need for
and the novelty of future 6G communication networks.

Keywords – 3D networking, 6G, beyond 5G, beyond Shannon, digital twin networking, goal oriented communications,
key performance indicators, native arti icial intelligence, semantic communications

1. INTRODUCTION key to realise the remote control of machines, and it also
allows people and machines to co‐work in the same real‐
Wireless cellular communication networks have seen the
virtual environment. That is why the setup of 5G mobile
rise of a so‐called new generation approximately every
systems is so important, even if low latency will only be
ten years. Each generation has always provided a dis‐
realised with the next 5G releases. To this end, the leader
ruptive technological advancement and societal change.
of 5G standardization body, the 3rd Generation Partner‐
The irst generation (1G) irst introduced analogue wire‐
ship Project (3GPP), has already prepared a clear road
less cellular technologies. On the other hand, the second
map with the next steps together with the International
generation (2G) was the irst wireless cellular network
Telecommunication Union (ITU). So it is not the case that
based on digital technologies. Next, the third generation
the development of 5G is complete. The 5G network is
(3G) not only provided the support for wireless voice tele‐
continuously evolving and will be adapted and optimised
phony but also for Internet access, video calls, and mo‐ to the tasks ahead.
bile television. Finally, the fourth generation (4G) was
the irst mobile cellular network with full support for In‐ However, 5G is not just an agnostic bit pipe, describing
ternet Protocol (IP) and access to Internet services. With the simple passing of bits, as in previous generations. The
the ifth generation (5G), the gateway to digitisation in in‐ new approach is achieved through the concept of soft‑
dustry has been pushed wide open. 5G has been address‐ warization. While its predecessors came in the form of
ing the support to controlling machines, and to give con‐ dedicated hardware, 5G is mainly based on tailored soft‐
nectivity to several applications besides industry, such ware solutions running on general‐purpose hardware,
as agriculture, the construction sector, the energy sec‐ referring to low‐cost, interchangeable and readily avail‐
tor with so‐called smart grids, and the Internet of Things able products. Various softwarization concepts such as
(IoT) also possible in real time. Software‐De ined Radio (SDR) or Software‐De ined Net‐
working (SDN) are going to enable network operators to
Before 5G, communication networks mainly focused on keep both Operational Expenditure (OPEX) and Capital
providing continuously higher data rates to offer high‐ Expenditure (CAPEX) low [1].
resolution streaming services. On the other hand, 5G has
been targeting the support for millions of devices at very Recently, the attention and the effort towards the next
low latency. Low latency combined with resilience are the generation (6G) has started both in the ic, public,

© International Telecommunication Union, 2021 1