Page 121 - ITU Kaleidoscope 2016

ICTs for a Sustainable World

and management of 5G networks in rural and low-income Exploitation of Commodity Hardware In traditional net-
zones. Our architecture is driven by the fact that the Internet works, where most of functionalities are hardware-coded,
connectivity is a primary need, that may be provided by the there is a clear lack of flexibility. Each device (either a Base
government or government-based entities rather than private Station, a router, or a computing node) is composed of pro-
ones. This alleviates the need of always guaranteeing a ROI. prietary hardware, which can be hardly managed in a con-
However, this process should be coupled with the reduction verged solution where all the network components and the
of the costs needed to deploy and manage the network. In services need to be controlled in a flexible way. In our vi-
the following, we sketch the proposed architecture. sion, the network components are softwarized, and therefore
it is possible to adopt general purpose hardware for most of
devices. Apart from the flexibility aspects, the exploitation
4.1. Main Pillars of commodity hardware has additionally two main advan-
tages: i) the costs of deploying the network can be cheaper
Converged Solution We believe that the services and the compared to high performance hardware-coded devices, and
networks should be managed in a converged way, following ii) since the hardware is the same for most of devices also
a trend that is currently emerging in 5G architectures [37]. In the operating expenses can be reduced (e.g., in terms of fail-
our scenario, the last mile of the network should be orches- ure costs). Clearly, the use of softwarized functions and
trated in conjunction with the metro and core one, without a commodity devices have an impact on the performance (e.g.,
complete separation between them, in contrast to current net- bandwidth and delay), which should be always taken into ac-
works. Additionally, the services are not running on ”top” count.
of the network, but they are lying at the same level of the
Solar-Powered Energy-Efficient Devices Since the power
network components. More in depth, the network provider is
also acting as service provider, and different computing com- grid is assumed to be not so widespread in rural zones and not
ponents (like storage, local DC, caches) are installed on most present or unreliable in low-income zones, a clear pulse will
network devices both in metro/core and access segments. As be the large exploitation of renewable energies to power the
a results, there is not a strict separation between the different physical devices. Among the available renewable sources,
parts of the network, thus enabling a global optimization of one of the most promising is the sun. Moreover, since most
the services and the network. This design choice is also justi- low-income zones are located in the regions of the earth re-
fied by the fact that rural and low-income zones will be likely ceiving the largest irradiation from this energy source, we
managed by government-based entities, which will then have expect that a large exploitation of solar panels will be a vi-
the highest flexibility to deploy the services and the different able approach. However, even though the solar power can be
components across the full network. predicted over time (thanks to weather forecasts), it is obvi-
ously not always available (e.g., during night or bad weather
Reusability of Network Components We believe that an-
conditions). In addition, the size of the solar panels is still
other of the main pillars will be the possibility to completely
an issue for the installation costs. Therefore, the elements of
virtualize most of the network components by means of vir-
a network have to carefully manage their energy consump-
tual functions that are shared among devices and managed
tion, by implementing, e.g., smart energy saving policies to
by a centralized entity. This trend is in line with current ef-
reduce the amount of power requested. These policies will
forts in the broad area of softwarization, which aims to bring
integrate both the knowledge of the power available and the
the network and computing functionalities from the hard-
variation of traffic experienced in the network over time.
ware space to the software environment. Even though the
performance of virtualized network elements is still lower Unmanned Aerial Vehicles and Advanced Radio Tech-
than fully hardware-based components, this constraint is less niques In order to limit the costs for installing and managing
stringent in rural and low-income zones compared to urban the devices, the number of nodes devoted to the last segment
ones, thanks to the fact that the strict requirements in terms of of the network should be reduced as much as possible. Fo-
high bandwidth and extremely low delays can be relaxed in cusing on wireless elements, we foresee the exploitation of
such contexts. Therefore, by letting each element to be com- different technologies. First of all, thanks to the recent ad-
posed of a set of virtual elements, it is possible to reuse the vances in Unmanned Aerial Vehicles (UAVs), the radio el-
same network components across different physical devices. ements may be mounted on top of them. For example, it
This feature triggers the possibility to implement smart re- would be possible to move the radio nodes in order to fol-
source allocation policies in order to move the network and low the (few) users in a rural network, thus preventing them
the computing capacity where it is really necessary or where from the lack of connectivity. In addition, radio elements
the sources of energy are currently available. Moreover, with can be deployed at higher altitudes, in order to exploit two
this capability the functionalities of network devices can be different features: i) the winds that can move such devices
directly modified by software upgrades, without the need of in the atmosphere, and ii) the fact that most users will expe-
changing the underlying hardware, which otherwise may be rience Line Of Sight (LOS) conditions, which will decrease
an expensive operation. Finally, thanks to the fact that the the propagation loss compared to classical Non Line of Sight
devices are split in software components, it is possible to in- (NLOS) conditions. In case of rural zones in which the num-
tegrate several functions in a single device, e.g., networking ber of users is not so low compared to the previous case,
and computing functions. the emerging technology of massive antenna arrays allows

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