Page 132 - Kaleidoscope Academic Conference Proceedings 2024

2024 ITU Kaleidoscope Academic Conference

(e) Integrated control & orchestration function: It 4.1 INCA Functions and Interfaces
formulates network control decisions by creating a list or The INCA functions implement the integrated network
configuration file containing the appropriate resource control architecture functions, interfaces and control
control parameters for each network segment involved in message flows as explained in the previous section. The
the E2E network service. These parameter lists are then INCA functions and integrated network control interfaces
sent to the control systems of the individual network are implemented in Python programming language. The
segments through the integrated network control interfaces. integrated network control interfaces use RESTful
3.3 Individual Network Segment Control Systems Application Program Interfaces (APIs) to communicate
with the controllers of individual network segments. The
The TN-NTN integrated network control system control parameters are exchanged in the JSON format.
architecture assumes that the individual network control
systems have functional components similar to those in the 4.2 TN-NTN Integrated Network Environment
integrated network control architecture. The key difference The TN-NTN integrated network environment includes the
is that the scope of each function is limited to a specific 5G RAN functions, 5GC functions, NTN
network segment rather than an E2E network service. simulator/emulator, and DN. The 5G RAN is based on
Individual network control system has two sets of interfaces: UERANSIM (https://github.com/aligungr/UERANSIM),
internal and external. Internal interfaces collect monitoring and the 5GC network functions are based on free5GC
data from physical or functional network elements at (https://free5gc.org). The 5GC network functions include
varying levels of granularity and time scales. External several functions such as Access and Mobility Management
interfaces connect to the integrated network control Function (AMF), Session Management Function (SMF),
interfaces to provide monitoring data and receiving control Policy Control Function (PCF), Network Exposure
parameters. Function (NEF), and Network Repository Function (NRF)
3.4 Control Signaling Message Flow in the control plane and the User Plane Function (UPF) in
the data plane. The 5GC functions are deployed in
ITU-T Y.3207 [6] describes the sequence of control standalone mode. More details about the 5GC network
signaling message flows to realize the INCA’s two key functions can be found in [12].
capabilities: The NTN is composed of a satellite network’s detail
(a) Creating network services that span both TN and NTN simulator in the control plane and an emulator of NTN
segments based on given QoS requirements. bandwidth, latency, jitter, and loss rates in the data plane,
(b) Monitoring performance and controlling resources to both developed in our lab. In this experimental system, the
maintain QoS, even with fluctuations in network conditions 5GC network functions are split into two groups: 5GC
such as changes in user numbers or traffic demands. (central) and 5GC (edge), and the NTN is inserted between
We have incorporated these message sequences into our them. The AMF and SMF are in the 5GC (edge) while the
experimental system. However, due to space constraints, remaining control plane network functions are in the 5GC
we will not provide the details here and instead refer (central). The UPFs are in both the 5GC (edge) and 5GC
readers to [5] for further information. (central).
The DN is configured in the OpenStack platform, whose
4. EXPERIMENTAL SYSTEM DEVELOPMENT components are managed by Open-Source MANO (OSM --
https://osm.etsi.org/). The DN contains video application
Figure 2 shows the layout of the experimental system that server configured with MPEG-DASH module installed in
we have developed in our lab. It consists of three blocks: 1) virtual machines (VMs) for streaming three different
INCA functions and integrated network control interfaces, quality video files. The video client program or player is
2) TN-NTN integrated network environment, and 3) installed in the user equipment (UE). Laptop computers are
Control operation visualization tools.
used to operate as UEs by installing the UE module of

1) INCA functions
Integrated network control interfaces
3) Control operation Control
visualization parameters Monitoring
data

2) TN-NTN integrated Interface Interface Interface Interface
network environment
5GC controller NTN controller 5GC controller DN controller
Simulator DN
5G mobile 5G mobile
RAN core (edge) Emulator core (central) App server

5G control signaling Data plane connectivity
UE
Figure 2 - Experimental system layout.

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