• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.10 no.7
• /
• pp.2936-2951
• /
• 2016

An emerging satellite technology, Operationally Responsive Space (ORS) is expected to provide a fast and flexible solution for emergency response, such as target tracking, dense earth observation, communicate relaying and so on. To realize large distance transmission, we propose the use of available relay satellites as relay nodes. Accordingly, we apply software defined network (SDN) technology to ORS networks. We additionally propose a satellite network architecture refered to as the SDN-based ORS-Satellite (Sat) networking scheme (SDOS). To overcome the issures of node failures and dynamic topology changes of satellite networks, we combine centralized and distributed routing mechanisms and propose a fast recovery routing algorithm (FRA) for SDOS. In this routing method, we use centralized routing as the base mode.The distributed opportunistic routing starts when node failures or congestion occur. The performance of the proposed routing method was validated through extensive computer simulations.The results demonstrate that the method is effective in terms of resoving low end-to-end delay, jitter and packet drops.

• Journal of Aerospace System Engineering
• /
• v.18 no.5
• /
• pp.27-32
• /
• 2024

As hegemonic rivalry between nations extends to the space domain, the race for pre-amption of low-Earth orbit is becoming intense. With the end of the U.S.-ROK missile guidelines, South Korea is focusing on establishing a space strategy for space security and developing space weapons systems. Nevertheless, there are challenges that need to be addressed to enhance its defense space power, such as a non-established acquisition process of space weapon system. This paper derived implications for the development of Korea's space defense capabilities using space operational concepts based on national security and space strategies. Improvement factors for process such as design test evaluation and Design Decision Review were then proposed for the acquisition of constellation satellites in the defense sector.