  Providing high-speed Internet service using satellite network has attracted
researchers from both academia and industry mainly due to the characteristics
of Low Earth Orbit (LEO) satellite networks such as global coverage,
scalability, and lower transmission delay. With the recent advancements in the
Software-Defined Network (SDN), implementation of SDN in Non-Terrestrial
Networks (NTN) can help to achieve the set goals for 5G and beyond networks.
Since satellite networks have a distinct architecture, some of the traditional
protocols no longer remain useful. Therefore, to satisfy the diverse Quality of
Service (QoS) requirements for a variety of applications, we propose a novel
and centralized QoS-aware routing algorithm, called fybrrLink in which the
global view of the network in SDN is utilized. We implement a modified
Bresenham's algorithm and Dijkstra's algorithm to find the optimal path in a
significantly reduced computation time. Also, taking advantage of the
deterministic satellite constellation, we propose a flow rule transfer
algorithm and a topology monitoring algorithm. Further, fybrrLink is evaluated
with multiple NS3 simulations, and results confirm its supremacy over other
state-of-the-art algorithms.
