Page 252 - Shaping smarter and more sustainable cities - Striving for sustainable development goals

Whether the access network is purely optical fiber‐to‐the home (FTTH) or based on a mixed
fiber/copper technology (fiber‐to‐the curb [FTTC], fiber‐to‐the business [FTTB]), the requirements
for operation and maintenance are changing dramatically compared to pure digital subscriber loop
(DSL)‐based access. At the same time, expectations have been set to reduce the maintenance effort
especially on the fiber network, because it is regarded as more reliable than copper.

XDSL (X Digital Subscriber Line)

This is a family of technologies that allows access to provide broadband access network over
conventional telephony (PSTN). Therefore, in the copper, the data are transmitted in a frequency
range higher than that used for voice, while avoiding the mutual interference. Implementation of
DSL modem requires placing a client (Modem) at home and an equipment (called Digital Subscriber
Line Access Multiplexer DSLAM) in the central operator. One of the main considerations in the
deployment of this technology is the length of the local loop, as given band width is inversely
proportional to this length.

The example in the following Figure shows how the different access networks connect homes.

Figure 27 – Broadband Access
Mobile Broadband Wireless Access Technologies

Wireless broadband technologies provide ubiquitous broadband access to mobile users and to all
kind of terminal equipment, enabling consumers with a broad range of mobility and a variety of
wireless multimedia services and applications. Broadband wireless access technologies provide
broadband data access through wireless media to consumer and business markets.
There have been continued efforts to deliver ubiquitous broadband wireless access by developing
and deploying advanced radio access technologies such as 3GPP UMTS and LTE, as well as mobile
WiMAX systems; commercially known as 3G and 4G technologies. In the future, it is expected that
5G will deliver higher speeds.
The broadband wireless access is also an attractive option to network operators in geographically
remote areas with no or limited wired network. The advantages in terms of savings in speed of
deployment and installation costs are further motivation for broadband wireless access
technologies.

242 ITU‐T's Technical Reports and Specifications