Page 111 - Kaleidoscope Academic Conference Proceedings 2021

Connecting physical and virtual worlds

immersive steering and control in remote environments 2.1.4 Integrated satellite-terrestrial network-enabled
along with novel immersive audio/video feeds. applications
Haptic communications are expected to form the backbone
of Industry 4.0 [4], along with other application domains It is expected that, in the future, applications will benefit of
where stringent ultra-low latency is coupled with novel seamlessly integrated space and terrestrial networks,
immersive audiovisual feeds, such as telehealth, online leveraging interconnected Low Earth Orbit (LEO) satellites
immersive gaming and remote collaboration. and other non-terrestrial networking nodes and platforms.
Advantages of such network integration include ubiquitous
network access at a global scale, enriched network paths for
better data delivery performance, ubiquitous edge caching
and computing services. And future mobile devices will be
able to directly communicate with the locally accessible
LEO satellite over the head, but without necessarily relying
on traditional ground station infrastructures.
Consider the IP addressing issue on extremely numerous
LEO satellites with their constellations, interworking
challenges with the terrestrial networks arise given the
dynamic interconnection of space IP addresses to different
terrestrial domains with different IP prefixes. The direct
connectivity of mobile devices with local satellites will also
require a cost-efficient addressing scheme avoiding address
translation operations.
Figure 2 – Remote surgery
Additionally, the routing, within the satellite networks as
Extremely low latency [8] (on the order of 5 ms or even less well as between them and the terrestrial networks, is
for a round-trip time under 10 ms and even as low as 1 ms in impacted by the novel IP addressing framework. An
some cases [9], time budgets are slightly longer for integrated routing scheme supporting these emerging
audiovisual feedback), zero packet loss (mission critical applications is highly recommended.
applications cannot tolerate packet retransmission due to
latency concerns), guaranteed high bandwidth (for visual
feed support) and strict synchronization (multiple data feeds
from hybrid sensory inputs and possibly arising from
different locations have to be rendered and acted on in unison
[10]) are required.

As far as latency, quantified exact latency requirements must
actually be met as, otherwise, not only the quality of
experience for users deteriorates, but the applications may
become unusable.
It is worthwhile to note that, due to the physical limitation of
the light speed, requirements on networking infrastructure
may be also imposed for efficient handling of the additional Figure 3 – Integrated satellite-terrestrial network
application functions, compute, and content close to the
network edge. Key network requirements include:
 Flexible addressing [13]
Key network requirements include:
 High bandwidth (especially important in case of remote  Integrated routing framework
monitoring)  Holistic path control policies
 Ultra-low and deterministic latency (from 5 ms to sub-ms  Coordinated management and admission control
level for instantaneous haptic feedback in tactile cases mechanisms
[11], [12])  Novel requirements at the satellite side (bandwidth
 Synchronization (significantly shorter than delay) [12] capacity, admission control, edge computing and storage)
 High security and reliability, privacy (for critical [14]
applications, e.g., those involving human lives and high-
value machinery) 2.2 Associated critical network challenges
 Prioritization (based on streams’ immediate relevance Emerging industrial applications will not only require
and criticality) abundant bandwidth and ubiquitous connectivity, networks
will also need to provide new capabilities that are not
supported today. Often large-data transmission is no longer

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