Online analysis of video data captured by sensor devices is increasingly required for applications such as object recognition in autonomous driving and abnormality detection by security cameras. However, there are several issues such as ensuring secure and stable communication environment between sensors and a cloud, collecting large amounts of various data and processing online video analysis efficiently. In this study, we have developed a prototype system of an online video processing mechanism using the SINET wide area data collection infrastructure called "mobile SINET" and show that the prototype system can collect a large amount of data using messaging infrastructure software in a secure and high-performance network environment, and online video processing is feasible using GPU nodes in a cloud. SINET is a wide-area academic network infrastructure and the mobile SINET is a service that provides mobile networks as an access network of SINET and enables direct connection to a SINET VPN. Each sensor can use the mobile SINET by installing a SIM for the SINET connection. In addition, we investigate the performance characteristics of messaging infrastructure and distributed stream processing infrastructure that constitute an online processing system in order to obtain design guidelines for IoT applications.