Page 21 - 5G Basics - Core Network Aspects
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Core network aspects 1
for FNs to provide users with the means to access appropriate data easily and without time-consuming
procedures, while providing accurate and correct data.
The amount and properties of digital data in networks are changing. Consumer-generated media are growing
in an explosive manner: social networking services are creating huge volumes of blog articles instantaneously;
ubiquitous sensor networks [ITU-T Y.2221] are generating massive amounts of digital data every second, and
some applications called "micro-blogs" generate quasi-real-time communication that includes multimedia
data. These data are produced, stored, and processed in networks in a distributed manner. In current IP
networks, users access these data in the network via conventional procedures, i.e., identifying the address
and port number of the host that provides the target data. Some data contain private information or digital
assets, but there are no built-in security mechanisms. More simple, efficient, and safe networking
technology, dedicated to handling huge volumes of data, will therefore be necessary in the future.
The traffic characteristics of such data communication are also changing. Traffic trends in FNs will depend
mainly on the location of data, rather than the distribution of subscribers. Because of cloud computing,
information and communication technology (ICT) resources, such as computing power and stored data in
data centres, are increasing. Combined with the proliferation of mobile devices having insufficient ICT
resources, this trend is shifting data processing from user terminals to data centres. FN designers therefore
need to pay close attention to these changes, e.g., the growing importance of communications in data
centres, and the huge number of transactions in and between data centres to fulfil user requests.
8.5 Energy consumption
FNs are recommended to use device-level, equipment-level, and network-level technologies to improve
energy efficiency, and to satisfy customers' demands, with minimum traffic. FN device-level, equipment-
level, and network-level technologies are recommended to not work independently, but rather to cooperate
with each other in achieving a solution for network energy savings.
Rationale: The lifecycle of a product includes phases such as raw material production, manufacturing, use,
and disposal, and all these phases need consideration in order to reduce the environmental impact. However,
energy consumption in the use-phase is usually the major issue for equipment operating 24 hours a day, as
is often the case in networks. Among the various types of energy consumption, electric power consumption
is usually predominant. Energy saving therefore plays a primary role in reducing the environmental impact
of networks.
Energy saving is also important for network operations. Necessary bandwidth usually increases as new
services and applications are added. However, energy consumption and its resulting heat may become a
significant physical limitation in the future, along with other physical limitations such as optical fibre capacity
or operational frequency of electrical devices. These issues may become a major operational obstacle and,
in the worst case, may prevent new services and applications from being offered.
Traditionally, energy reduction has been achieved mostly by a device-level approach, i.e., by miniaturization
of semiconductor processing rules and the process integration of electrical devices. However, this approach
is facing difficulties such as high standby power and the physical limits of operational frequency. Therefore,
not only device-level approaches, such as power reduction of electrical and optical devices, but also
equipment-level and network-level approaches are essential in the future.
Switching in the optical domain uses less power than switching in the electronic domain, but packet queues
are not easy to implement without electronic memory. Also, circuit switching uses less power than
connectionless packet switching.
Networking nodes, such as switches and routers, should be designed considering smart sleep mode
mechanisms, as with existing cell phones; this is an equipment-level approach. For network-level approaches,
power-effective traffic control should be considered. A typical example is the use of routing methods that
reduce the peak amount of traffic. Another example is caching and filtering, which reduce the amount of
data that needs to be transmitted.
Device-level, equipment-level, and network-level energy-saving approaches that consider both improving
energy efficiency and reducing inessential traffic, are key factors of energy saving in FNs.
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