The Network Tube is the 21st century version of the life preserver. This water ring was designed by Son Kijo, Joon Hyoung Seo, Uhm Hyung Woo, Choi JinYoung and Kim Junpyo to help keep shipwreck survivors together and makes them easier to locate by rescuers.
The Network Tube is equipped with a GPS tracking system. This system makes survivors out in the ocean easier to find. The ocean is a big place, and there is only so much ground airplanes and ships can cover in search of shipwrecked survivors. Giving rescuers a way to track people would greatly increase the odds of finding them. The Network Tube seems like it would be relatively simple to create, with the benefits far outweighing the costs.