In effect, fiber is needed to realize the benefits
of C-RAN, NFV, SDN, MEC, and SBA.
These concepts/technologies are critical pillars
for 5G and future cloud-native networks.
12 I ICT TODAY
when dark fiber is used or when critical services
(e.g., healthcare) mandate the highest level of reliability.
Standardization
The number of optical transport options, including pointto
point (P2P) wavelength division multiplexing (WDM)
and time and wavelength division multiplexing (TWDM)
PON, as well as P2P WDM overlay, are important considerations
for 5G and fixed wireless access too. Factors, such
as capacity, latency support, cost, and reuse of the existing
fiber infrastructure, are key in assessing the relevance of
these options to 5G. Next-generation PON2 (NG-PON2)
TWDM-enabled is already being discussed in the context
of 5G. The need for guaranteed throughput, latency and
reliability has led to the development of standards, including
time-sensitive networking (TSN) and FlexE (or FlexEthernet)
for 5G transport. The fronthaul-related specification
of enhanced common public radio interface (eCPRI) and
the requirement for scalable and higher bandwidth
front/mid/back/cross-haul support with 100 Gb/s and
400 Gb/s Ethernet data rates being considered are some
of the multiple facets of standardization.
Focusing on the mobile transport domain, the push
for open network architectures is manifested by the emergence
of industry organizations and workgroups. The
O-RAN Alliance and OpenRAN (part of the Telecom Infra
Project), for example, are promoting open architectures
and interfaces for virtualized radio access networks.
Moving away from non-proprietary standards to simplify
and optimize the use of fiber infrastructure is driving the
requirements for next-generation transport. The sooner
the relevant standards become finalized and mature,
the better.
providers or enterprise/private networks as needed
(i.e., in a more flexible manner than the model currently
followed by mobile virtual network operators).
These opportunities also highlight the importance
of the underlying fiber infrastructure and the need
to address all FiberG-related challenges.
CHALLENGES FOR FiberG
FiberG has a number of challenges to address, including:
• High and low-level
• New and old
• Global and regional
• Commercial and technical
The advent of 5G has not made things easier.
Investment Focus
Practical challenges, such as digging when rolling out
fiber, contribute to its overall rollout cost. In addition,
the versatile nature of 5G further complicates the relevant
decision-making and dimensioning processes. Operators
must identify their use cases to target in the future how
much additional fiber they should lay, perhaps to support
other operators as part of infrastructure sharing and
to decide with whom they should be partnering including
industry or local government.
As part of their ROI focus, network operators should
also be open to alternative options whenever a fiber roll-
out appears to be challenging or altogether prohibitive.
Regulation
Regulation covers a variety of areas from the need to
obtain permission for fiber installation/upgrades to the
crucial role of fiber in 5G end-to-end network slicing. It
will be interesting to see
how SLAs for 5G services
are monitored. It will also
be intriguing to consider
the regulations and possible
penalties imposed in the
case of degradation/outages
if network slice performance
is affected by fiber issues,
as well as how fiber network
operators will be regulated