This book gathers papers presented at the 9th International Conference on Computer Engineering and Networks (CENet2019), held in Changsha, China, on October 18-20, 2019. It examines innovations in the fields of computer engineering and networking and explores important, state-of-the-art developments in areas such as Information Security, Information Hiding and Cryptography, Cyber Security, and Intelligent Computing and Applications. The book also covers emerging topics in computer engineering and networking, along with their applications, discusses how to improve productivity by using the latest advanced technologies, and examines innovation in the fields of computer engineering and networking, particularly in intelligent computing and security.